60 files changed, 2339 insertions, 755 deletions

diff --git a/crates/ra_cargo_watch/src/conv.rs b/crates/ra_cargo_watch/src/conv.rs
index 0246adfb5..c6f8ca329 100644
--- a/crates/ra_cargo_watch/src/conv.rs
+++ b/crates/ra_cargo_watch/src/conv.rs
@@ -8,6 +8,7 @@ use lsp_types::{
     Location, NumberOrString, Position, Range, TextEdit, Url, WorkspaceEdit,
 };
 use std::{
+    collections::HashMap,
     fmt::Write,
     path::{Component, Path, PathBuf, Prefix},
     str::FromStr,
@@ -126,44 +127,34 @@ fn map_rust_child_diagnostic(
     rd: &RustDiagnostic,
     workspace_root: &PathBuf,
 ) -> MappedRustChildDiagnostic {
-    let span: &DiagnosticSpan = match rd.spans.iter().find(|s| s.is_primary) {
-        Some(span) => span,
-        None => {
-            // `rustc` uses these spanless children as a way to print multi-line
-            // messages
-            return MappedRustChildDiagnostic::MessageLine(rd.message.clone());
+    let spans: Vec<&DiagnosticSpan> = rd.spans.iter().filter(|s| s.is_primary).collect();
+    if spans.is_empty() {
+        // `rustc` uses these spanless children as a way to print multi-line
+        // messages
+        return MappedRustChildDiagnostic::MessageLine(rd.message.clone());
+    }
+
+    let mut edit_map: HashMap<Url, Vec<TextEdit>> = HashMap::new();
+    for &span in &spans {
+        if let Some(suggested_replacement) = &span.suggested_replacement {
+            let location = map_span_to_location(span, workspace_root);
+            let edit = TextEdit::new(location.range, suggested_replacement.clone());
+            edit_map.entry(location.uri).or_default().push(edit);
         }
-    };
-
-    // If we have a primary span use its location, otherwise use the parent
-    let location = map_span_to_location(&span, workspace_root);
-
-    if let Some(suggested_replacement) = &span.suggested_replacement {
-        // Include our replacement in the title unless it's empty
-        let title = if !suggested_replacement.is_empty() {
-            format!("{}: '{}'", rd.message, suggested_replacement)
-        } else {
-            rd.message.clone()
-        };
-
-        let edit = {
-            let edits = vec![TextEdit::new(location.range, suggested_replacement.clone())];
-            let mut edit_map = std::collections::HashMap::new();
-            edit_map.insert(location.uri, edits);
-            WorkspaceEdit::new(edit_map)
-        };
+    }
 
+    if !edit_map.is_empty() {
         MappedRustChildDiagnostic::SuggestedFix(CodeAction {
-            title,
+            title: rd.message.clone(),
             kind: Some("quickfix".to_string()),
             diagnostics: None,
-            edit: Some(edit),
+            edit: Some(WorkspaceEdit::new(edit_map)),
             command: None,
             is_preferred: None,
         })
     } else {
         MappedRustChildDiagnostic::Related(DiagnosticRelatedInformation {
-            location,
+            location: map_span_to_location(spans[0], workspace_root),
             message: rd.message.clone(),
         })
     }
@@ -189,13 +180,13 @@ pub(crate) struct MappedRustDiagnostic {
 pub(crate) fn map_rust_diagnostic_to_lsp(
     rd: &RustDiagnostic,
     workspace_root: &PathBuf,
-) -> Option<MappedRustDiagnostic> {
-    let primary_span = rd.spans.iter().find(|s| s.is_primary)?;
-
-    let location = map_span_to_location(&primary_span, workspace_root);
+) -> Vec<MappedRustDiagnostic> {
+    let primary_spans: Vec<&DiagnosticSpan> = rd.spans.iter().filter(|s| s.is_primary).collect();
+    if primary_spans.is_empty() {
+        return vec![];
+    }
 
     let severity = map_level_to_severity(rd.level);
-    let mut primary_span_label = primary_span.label.as_ref();
 
     let mut source = String::from("rustc");
     let mut code = rd.code.as_ref().map(|c| c.code.clone());
@@ -208,19 +199,10 @@ pub(crate) fn map_rust_diagnostic_to_lsp(
         }
     }
 
+    let mut needs_primary_span_label = true;
     let mut related_information = vec![];
     let mut tags = vec![];
 
-    // If error occurs from macro expansion, add related info pointing to
-    // where the error originated
-    if !is_from_macro(&primary_span.file_name) && primary_span.expansion.is_some() {
-        let def_loc = map_span_to_location_naive(&primary_span, workspace_root);
-        related_information.push(DiagnosticRelatedInformation {
-            location: def_loc,
-            message: "Error originated from macro here".to_string(),
-        });
-    }
-
     for secondary_span in rd.spans.iter().filter(|s| !s.is_primary) {
         let related = map_secondary_span_to_related(secondary_span, workspace_root);
         if let Some(related) = related {
@@ -240,15 +222,11 @@ pub(crate) fn map_rust_diagnostic_to_lsp(
 
                 // These secondary messages usually duplicate the content of the
                 // primary span label.
-                primary_span_label = None;
+                needs_primary_span_label = false;
             }
         }
     }
 
-    if let Some(primary_span_label) = primary_span_label {
-        write!(&mut message, "\n{}", primary_span_label).unwrap();
-    }
-
     if is_unused_or_unnecessary(rd) {
         tags.push(DiagnosticTag::Unnecessary);
     }
@@ -257,21 +235,45 @@ pub(crate) fn map_rust_diagnostic_to_lsp(
         tags.push(DiagnosticTag::Deprecated);
     }
 
-    let diagnostic = Diagnostic {
-        range: location.range,
-        severity,
-        code: code.map(NumberOrString::String),
-        source: Some(source),
-        message,
-        related_information: if !related_information.is_empty() {
-            Some(related_information)
-        } else {
-            None
-        },
-        tags: if !tags.is_empty() { Some(tags) } else { None },
-    };
-
-    Some(MappedRustDiagnostic { location, diagnostic, fixes })
+    primary_spans
+        .iter()
+        .map(|primary_span| {
+            let location = map_span_to_location(&primary_span, workspace_root);
+
+            let mut message = message.clone();
+            if needs_primary_span_label {
+                if let Some(primary_span_label) = &primary_span.label {
+                    write!(&mut message, "\n{}", primary_span_label).unwrap();
+                }
+            }
+
+            // If error occurs from macro expansion, add related info pointing to
+            // where the error originated
+            if !is_from_macro(&primary_span.file_name) && primary_span.expansion.is_some() {
+                let def_loc = map_span_to_location_naive(&primary_span, workspace_root);
+                related_information.push(DiagnosticRelatedInformation {
+                    location: def_loc,
+                    message: "Error originated from macro here".to_string(),
+                });
+            }
+
+            let diagnostic = Diagnostic {
+                range: location.range,
+                severity,
+                code: code.clone().map(NumberOrString::String),
+                source: Some(source.clone()),
+                message,
+                related_information: if !related_information.is_empty() {
+                    Some(related_information.clone())
+                } else {
+                    None
+                },
+                tags: if !tags.is_empty() { Some(tags.clone()) } else { None },
+            };
+
+            MappedRustDiagnostic { location, diagnostic, fixes: fixes.clone() }
+        })
+        .collect()
 }
 
 /// Returns a `Url` object from a given path, will lowercase drive letters if present.
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_clippy_pass_by_ref.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_clippy_pass_by_ref.snap
index 95ca163dc..9e8f4eff4 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_clippy_pass_by_ref.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_clippy_pass_by_ref.snap
@@ -2,98 +2,100 @@
 source: crates/ra_cargo_watch/src/conv/test.rs
 expression: diag
 ---
-MappedRustDiagnostic {
-    location: Location {
-        uri: "file:///test/compiler/mir/tagset.rs",
-        range: Range {
-            start: Position {
-                line: 41,
-                character: 23,
-            },
-            end: Position {
-                line: 41,
-                character: 28,
+[
+    MappedRustDiagnostic {
+        location: Location {
+            uri: "file:///test/compiler/mir/tagset.rs",
+            range: Range {
+                start: Position {
+                    line: 41,
+                    character: 23,
+                },
+                end: Position {
+                    line: 41,
+                    character: 28,
+                },
             },
         },
-    },
-    diagnostic: Diagnostic {
-        range: Range {
-            start: Position {
-                line: 41,
-                character: 23,
-            },
-            end: Position {
-                line: 41,
-                character: 28,
+        diagnostic: Diagnostic {
+            range: Range {
+                start: Position {
+                    line: 41,
+                    character: 23,
+                },
+                end: Position {
+                    line: 41,
+                    character: 28,
+                },
             },
-        },
-        severity: Some(
-            Warning,
-        ),
-        code: Some(
-            String(
-                "trivially_copy_pass_by_ref",
+            severity: Some(
+                Warning,
             ),
-        ),
-        source: Some(
-            "clippy",
-        ),
-        message: "this argument is passed by reference, but would be more efficient if passed by value\n#[warn(clippy::trivially_copy_pass_by_ref)] implied by #[warn(clippy::all)]\nfor further information visit https://rust-lang.github.io/rust-clippy/master/index.html#trivially_copy_pass_by_ref",
-        related_information: Some(
-            [
-                DiagnosticRelatedInformation {
-                    location: Location {
-                        uri: "file:///test/compiler/lib.rs",
-                        range: Range {
-                            start: Position {
-                                line: 0,
-                                character: 8,
-                            },
-                            end: Position {
-                                line: 0,
-                                character: 19,
+            code: Some(
+                String(
+                    "trivially_copy_pass_by_ref",
+                ),
+            ),
+            source: Some(
+                "clippy",
+            ),
+            message: "this argument is passed by reference, but would be more efficient if passed by value\n#[warn(clippy::trivially_copy_pass_by_ref)] implied by #[warn(clippy::all)]\nfor further information visit https://rust-lang.github.io/rust-clippy/master/index.html#trivially_copy_pass_by_ref",
+            related_information: Some(
+                [
+                    DiagnosticRelatedInformation {
+                        location: Location {
+                            uri: "file:///test/compiler/lib.rs",
+                            range: Range {
+                                start: Position {
+                                    line: 0,
+                                    character: 8,
+                                },
+                                end: Position {
+                                    line: 0,
+                                    character: 19,
+                                },
                             },
                         },
+                        message: "lint level defined here",
                     },
-                    message: "lint level defined here",
-                },
-            ],
-        ),
-        tags: None,
-    },
-    fixes: [
-        CodeAction {
-            title: "consider passing by value instead: \'self\'",
-            kind: Some(
-                "quickfix",
+                ],
             ),
-            diagnostics: None,
-            edit: Some(
-                WorkspaceEdit {
-                    changes: Some(
-                        {
-                            "file:///test/compiler/mir/tagset.rs": [
-                                TextEdit {
-                                    range: Range {
-                                        start: Position {
-                                            line: 41,
-                                            character: 23,
-                                        },
-                                        end: Position {
-                                            line: 41,
-                                            character: 28,
+            tags: None,
+        },
+        fixes: [
+            CodeAction {
+                title: "consider passing by value instead",
+                kind: Some(
+                    "quickfix",
+                ),
+                diagnostics: None,
+                edit: Some(
+                    WorkspaceEdit {
+                        changes: Some(
+                            {
+                                "file:///test/compiler/mir/tagset.rs": [
+                                    TextEdit {
+                                        range: Range {
+                                            start: Position {
+                                                line: 41,
+                                                character: 23,
+                                            },
+                                            end: Position {
+                                                line: 41,
+                                                character: 28,
+                                            },
                                         },
+                                        new_text: "self",
                                     },
-                                    new_text: "self",
-                                },
-                            ],
-                        },
-                    ),
-                    document_changes: None,
-                },
-            ),
-            command: None,
-            is_preferred: None,
-        },
-    ],
-}
+                                ],
+                            },
+                        ),
+                        document_changes: None,
+                    },
+                ),
+                command: None,
+                is_preferred: None,
+            },
+        ],
+    },
+]
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_handles_macro_location.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_handles_macro_location.snap
index 12eb32df4..61ae0c9ae 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_handles_macro_location.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_handles_macro_location.snap
@@ -2,45 +2,47 @@
 source: crates/ra_cargo_watch/src/conv/test.rs
 expression: diag
 ---
-MappedRustDiagnostic {
-    location: Location {
-        uri: "file:///test/src/main.rs",
-        range: Range {
-            start: Position {
-                line: 1,
-                character: 4,
-            },
-            end: Position {
-                line: 1,
-                character: 26,
+[
+    MappedRustDiagnostic {
+        location: Location {
+            uri: "file:///test/src/main.rs",
+            range: Range {
+                start: Position {
+                    line: 1,
+                    character: 4,
+                },
+                end: Position {
+                    line: 1,
+                    character: 26,
+                },
             },
         },
-    },
-    diagnostic: Diagnostic {
-        range: Range {
-            start: Position {
-                line: 1,
-                character: 4,
+        diagnostic: Diagnostic {
+            range: Range {
+                start: Position {
+                    line: 1,
+                    character: 4,
+                },
+                end: Position {
+                    line: 1,
+                    character: 26,
+                },
             },
-            end: Position {
-                line: 1,
-                character: 26,
-            },
-        },
-        severity: Some(
-            Error,
-        ),
-        code: Some(
-            String(
-                "E0277",
+            severity: Some(
+                Error,
             ),
-        ),
-        source: Some(
-            "rustc",
-        ),
-        message: "can\'t compare `{integer}` with `&str`\nthe trait `std::cmp::PartialEq<&str>` is not implemented for `{integer}`",
-        related_information: None,
-        tags: None,
+            code: Some(
+                String(
+                    "E0277",
+                ),
+            ),
+            source: Some(
+                "rustc",
+            ),
+            message: "can\'t compare `{integer}` with `&str`\nthe trait `std::cmp::PartialEq<&str>` is not implemented for `{integer}`",
+            related_information: None,
+            tags: None,
+        },
+        fixes: [],
     },
-    fixes: [],
-}
+]
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_macro_compiler_error.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_macro_compiler_error.snap
index 7b83a7cd0..641da1a58 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_macro_compiler_error.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_macro_compiler_error.snap
@@ -2,60 +2,62 @@
 source: crates/ra_cargo_watch/src/conv/test.rs
 expression: diag
 ---
-MappedRustDiagnostic {
-    location: Location {
-        uri: "file:///test/crates/ra_hir_def/src/data.rs",
-        range: Range {
-            start: Position {
-                line: 79,
-                character: 15,
-            },
-            end: Position {
-                line: 79,
-                character: 41,
+[
+    MappedRustDiagnostic {
+        location: Location {
+            uri: "file:///test/crates/ra_hir_def/src/data.rs",
+            range: Range {
+                start: Position {
+                    line: 79,
+                    character: 15,
+                },
+                end: Position {
+                    line: 79,
+                    character: 41,
+                },
             },
         },
-    },
-    diagnostic: Diagnostic {
-        range: Range {
-            start: Position {
-                line: 79,
-                character: 15,
-            },
-            end: Position {
-                line: 79,
-                character: 41,
+        diagnostic: Diagnostic {
+            range: Range {
+                start: Position {
+                    line: 79,
+                    character: 15,
+                },
+                end: Position {
+                    line: 79,
+                    character: 41,
+                },
             },
-        },
-        severity: Some(
-            Error,
-        ),
-        code: None,
-        source: Some(
-            "rustc",
-        ),
-        message: "Please register your known path in the path module",
-        related_information: Some(
-            [
-                DiagnosticRelatedInformation {
-                    location: Location {
-                        uri: "file:///test/crates/ra_hir_def/src/path.rs",
-                        range: Range {
-                            start: Position {
-                                line: 264,
-                                character: 8,
-                            },
-                            end: Position {
-                                line: 264,
-                                character: 76,
+            severity: Some(
+                Error,
+            ),
+            code: None,
+            source: Some(
+                "rustc",
+            ),
+            message: "Please register your known path in the path module",
+            related_information: Some(
+                [
+                    DiagnosticRelatedInformation {
+                        location: Location {
+                            uri: "file:///test/crates/ra_hir_def/src/path.rs",
+                            range: Range {
+                                start: Position {
+                                    line: 264,
+                                    character: 8,
+                                },
+                                end: Position {
+                                    line: 264,
+                                    character: 76,
+                                },
                             },
                         },
+                        message: "Error originated from macro here",
                     },
-                    message: "Error originated from macro here",
-                },
-            ],
-        ),
-        tags: None,
+                ],
+            ),
+            tags: None,
+        },
+        fixes: [],
     },
-    fixes: [],
-}
+]
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_multi_line_fix.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_multi_line_fix.snap
new file mode 100644
index 000000000..0557a2e79
--- /dev/null
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_multi_line_fix.snap
@@ -0,0 +1,114 @@
+---
+source: crates/ra_cargo_watch/src/conv/test.rs
+expression: diag
+---
+[
+    MappedRustDiagnostic {
+        location: Location {
+            uri: "file:///test/src/main.rs",
+            range: Range {
+                start: Position {
+                    line: 3,
+                    character: 4,
+                },
+                end: Position {
+                    line: 3,
+                    character: 5,
+                },
+            },
+        },
+        diagnostic: Diagnostic {
+            range: Range {
+                start: Position {
+                    line: 3,
+                    character: 4,
+                },
+                end: Position {
+                    line: 3,
+                    character: 5,
+                },
+            },
+            severity: Some(
+                Warning,
+            ),
+            code: Some(
+                String(
+                    "let_and_return",
+                ),
+            ),
+            source: Some(
+                "clippy",
+            ),
+            message: "returning the result of a let binding from a block\n`#[warn(clippy::let_and_return)]` on by default\nfor further information visit https://rust-lang.github.io/rust-clippy/master/index.html#let_and_return",
+            related_information: Some(
+                [
+                    DiagnosticRelatedInformation {
+                        location: Location {
+                            uri: "file:///test/src/main.rs",
+                            range: Range {
+                                start: Position {
+                                    line: 2,
+                                    character: 4,
+                                },
+                                end: Position {
+                                    line: 2,
+                                    character: 30,
+                                },
+                            },
+                        },
+                        message: "unnecessary let binding",
+                    },
+                ],
+            ),
+            tags: None,
+        },
+        fixes: [
+            CodeAction {
+                title: "return the expression directly",
+                kind: Some(
+                    "quickfix",
+                ),
+                diagnostics: None,
+                edit: Some(
+                    WorkspaceEdit {
+                        changes: Some(
+                            {
+                                "file:///test/src/main.rs": [
+                                    TextEdit {
+                                        range: Range {
+                                            start: Position {
+                                                line: 2,
+                                                character: 4,
+                                            },
+                                            end: Position {
+                                                line: 2,
+                                                character: 30,
+                                            },
+                                        },
+                                        new_text: "",
+                                    },
+                                    TextEdit {
+                                        range: Range {
+                                            start: Position {
+                                                line: 3,
+                                                character: 4,
+                                            },
+                                            end: Position {
+                                                line: 3,
+                                                character: 5,
+                                            },
+                                        },
+                                        new_text: "(0..10).collect()",
+                                    },
+                                ],
+                            },
+                        ),
+                        document_changes: None,
+                    },
+                ),
+                command: None,
+                is_preferred: None,
+            },
+        ],
+    },
+]
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_incompatible_type_for_trait.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_incompatible_type_for_trait.snap
index 54679c5db..754bc33a4 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_incompatible_type_for_trait.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_incompatible_type_for_trait.snap
@@ -2,45 +2,47 @@
 source: crates/ra_cargo_watch/src/conv/test.rs
 expression: diag
 ---
-MappedRustDiagnostic {
-    location: Location {
-        uri: "file:///test/compiler/ty/list_iter.rs",
-        range: Range {
-            start: Position {
-                line: 51,
-                character: 4,
-            },
-            end: Position {
-                line: 51,
-                character: 47,
+[
+    MappedRustDiagnostic {
+        location: Location {
+            uri: "file:///test/compiler/ty/list_iter.rs",
+            range: Range {
+                start: Position {
+                    line: 51,
+                    character: 4,
+                },
+                end: Position {
+                    line: 51,
+                    character: 47,
+                },
             },
         },
-    },
-    diagnostic: Diagnostic {
-        range: Range {
-            start: Position {
-                line: 51,
-                character: 4,
+        diagnostic: Diagnostic {
+            range: Range {
+                start: Position {
+                    line: 51,
+                    character: 4,
+                },
+                end: Position {
+                    line: 51,
+                    character: 47,
+                },
             },
-            end: Position {
-                line: 51,
-                character: 47,
-            },
-        },
-        severity: Some(
-            Error,
-        ),
-        code: Some(
-            String(
-                "E0053",
+            severity: Some(
+                Error,
             ),
-        ),
-        source: Some(
-            "rustc",
-        ),
-        message: "method `next` has an incompatible type for trait\nexpected type `fn(&mut ty::list_iter::ListIterator<\'list, M>) -> std::option::Option<&ty::Ref<M>>`\n   found type `fn(&ty::list_iter::ListIterator<\'list, M>) -> std::option::Option<&\'list ty::Ref<M>>`",
-        related_information: None,
-        tags: None,
+            code: Some(
+                String(
+                    "E0053",
+                ),
+            ),
+            source: Some(
+                "rustc",
+            ),
+            message: "method `next` has an incompatible type for trait\nexpected type `fn(&mut ty::list_iter::ListIterator<\'list, M>) -> std::option::Option<&ty::Ref<M>>`\n   found type `fn(&ty::list_iter::ListIterator<\'list, M>) -> std::option::Option<&\'list ty::Ref<M>>`",
+            related_information: None,
+            tags: None,
+        },
+        fixes: [],
     },
-    fixes: [],
-}
+]
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_mismatched_type.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_mismatched_type.snap
index 57df4ceaf..78b7f7cc8 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_mismatched_type.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_mismatched_type.snap
@@ -2,45 +2,47 @@
 source: crates/ra_cargo_watch/src/conv/test.rs
 expression: diag
 ---
-MappedRustDiagnostic {
-    location: Location {
-        uri: "file:///test/runtime/compiler_support.rs",
-        range: Range {
-            start: Position {
-                line: 47,
-                character: 64,
-            },
-            end: Position {
-                line: 47,
-                character: 69,
+[
+    MappedRustDiagnostic {
+        location: Location {
+            uri: "file:///test/runtime/compiler_support.rs",
+            range: Range {
+                start: Position {
+                    line: 47,
+                    character: 64,
+                },
+                end: Position {
+                    line: 47,
+                    character: 69,
+                },
             },
         },
-    },
-    diagnostic: Diagnostic {
-        range: Range {
-            start: Position {
-                line: 47,
-                character: 64,
+        diagnostic: Diagnostic {
+            range: Range {
+                start: Position {
+                    line: 47,
+                    character: 64,
+                },
+                end: Position {
+                    line: 47,
+                    character: 69,
+                },
             },
-            end: Position {
-                line: 47,
-                character: 69,
-            },
-        },
-        severity: Some(
-            Error,
-        ),
-        code: Some(
-            String(
-                "E0308",
+            severity: Some(
+                Error,
             ),
-        ),
-        source: Some(
-            "rustc",
-        ),
-        message: "mismatched types\nexpected usize, found u32",
-        related_information: None,
-        tags: None,
+            code: Some(
+                String(
+                    "E0308",
+                ),
+            ),
+            source: Some(
+                "rustc",
+            ),
+            message: "mismatched types\nexpected usize, found u32",
+            related_information: None,
+            tags: None,
+        },
+        fixes: [],
     },
-    fixes: [],
-}
+]
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_unused_variable.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_unused_variable.snap
index 3e1fe736c..5989ed202 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_unused_variable.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_unused_variable.snap
@@ -2,83 +2,85 @@
 source: crates/ra_cargo_watch/src/conv/test.rs
 expression: diag
 ---
-MappedRustDiagnostic {
-    location: Location {
-        uri: "file:///test/driver/subcommand/repl.rs",
-        range: Range {
-            start: Position {
-                line: 290,
-                character: 8,
-            },
-            end: Position {
-                line: 290,
-                character: 11,
+[
+    MappedRustDiagnostic {
+        location: Location {
+            uri: "file:///test/driver/subcommand/repl.rs",
+            range: Range {
+                start: Position {
+                    line: 290,
+                    character: 8,
+                },
+                end: Position {
+                    line: 290,
+                    character: 11,
+                },
             },
         },
-    },
-    diagnostic: Diagnostic {
-        range: Range {
-            start: Position {
-                line: 290,
-                character: 8,
-            },
-            end: Position {
-                line: 290,
-                character: 11,
+        diagnostic: Diagnostic {
+            range: Range {
+                start: Position {
+                    line: 290,
+                    character: 8,
+                },
+                end: Position {
+                    line: 290,
+                    character: 11,
+                },
             },
-        },
-        severity: Some(
-            Warning,
-        ),
-        code: Some(
-            String(
-                "unused_variables",
+            severity: Some(
+                Warning,
             ),
-        ),
-        source: Some(
-            "rustc",
-        ),
-        message: "unused variable: `foo`\n#[warn(unused_variables)] on by default",
-        related_information: None,
-        tags: Some(
-            [
-                Unnecessary,
-            ],
-        ),
-    },
-    fixes: [
-        CodeAction {
-            title: "consider prefixing with an underscore: \'_foo\'",
-            kind: Some(
-                "quickfix",
+            code: Some(
+                String(
+                    "unused_variables",
+                ),
             ),
-            diagnostics: None,
-            edit: Some(
-                WorkspaceEdit {
-                    changes: Some(
-                        {
-                            "file:///test/driver/subcommand/repl.rs": [
-                                TextEdit {
-                                    range: Range {
-                                        start: Position {
-                                            line: 290,
-                                            character: 8,
-                                        },
-                                        end: Position {
-                                            line: 290,
-                                            character: 11,
-                                        },
-                                    },
-                                    new_text: "_foo",
-                                },
-                            ],
-                        },
-                    ),
-                    document_changes: None,
-                },
+            source: Some(
+                "rustc",
+            ),
+            message: "unused variable: `foo`\n#[warn(unused_variables)] on by default",
+            related_information: None,
+            tags: Some(
+                [
+                    Unnecessary,
+                ],
             ),
-            command: None,
-            is_preferred: None,
         },
-    ],
-}
+        fixes: [
+            CodeAction {
+                title: "consider prefixing with an underscore",
+                kind: Some(
+                    "quickfix",
+                ),
+                diagnostics: None,
+                edit: Some(
+                    WorkspaceEdit {
+                        changes: Some(
+                            {
+                                "file:///test/driver/subcommand/repl.rs": [
+                                    TextEdit {
+                                        range: Range {
+                                            start: Position {
+                                                line: 290,
+                                                character: 8,
+                                            },
+                                            end: Position {
+                                                line: 290,
+                                                character: 11,
+                                            },
+                                        },
+                                        new_text: "_foo",
+                                    },
+                                ],
+                            },
+                        ),
+                        document_changes: None,
+                    },
+                ),
+                command: None,
+                is_preferred: None,
+            },
+        ],
+    },
+]
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_wrong_number_of_parameters.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_wrong_number_of_parameters.snap
index 69301078d..e34b546dc 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_wrong_number_of_parameters.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_wrong_number_of_parameters.snap
@@ -2,64 +2,66 @@
 source: crates/ra_cargo_watch/src/conv/test.rs
 expression: diag
 ---
-MappedRustDiagnostic {
-    location: Location {
-        uri: "file:///test/compiler/ty/select.rs",
-        range: Range {
-            start: Position {
-                line: 103,
-                character: 17,
-            },
-            end: Position {
-                line: 103,
-                character: 29,
+[
+    MappedRustDiagnostic {
+        location: Location {
+            uri: "file:///test/compiler/ty/select.rs",
+            range: Range {
+                start: Position {
+                    line: 103,
+                    character: 17,
+                },
+                end: Position {
+                    line: 103,
+                    character: 29,
+                },
             },
         },
-    },
-    diagnostic: Diagnostic {
-        range: Range {
-            start: Position {
-                line: 103,
-                character: 17,
-            },
-            end: Position {
-                line: 103,
-                character: 29,
+        diagnostic: Diagnostic {
+            range: Range {
+                start: Position {
+                    line: 103,
+                    character: 17,
+                },
+                end: Position {
+                    line: 103,
+                    character: 29,
+                },
             },
-        },
-        severity: Some(
-            Error,
-        ),
-        code: Some(
-            String(
-                "E0061",
+            severity: Some(
+                Error,
             ),
-        ),
-        source: Some(
-            "rustc",
-        ),
-        message: "this function takes 2 parameters but 3 parameters were supplied\nexpected 2 parameters",
-        related_information: Some(
-            [
-                DiagnosticRelatedInformation {
-                    location: Location {
-                        uri: "file:///test/compiler/ty/select.rs",
-                        range: Range {
-                            start: Position {
-                                line: 218,
-                                character: 4,
-                            },
-                            end: Position {
-                                line: 230,
-                                character: 5,
+            code: Some(
+                String(
+                    "E0061",
+                ),
+            ),
+            source: Some(
+                "rustc",
+            ),
+            message: "this function takes 2 parameters but 3 parameters were supplied\nexpected 2 parameters",
+            related_information: Some(
+                [
+                    DiagnosticRelatedInformation {
+                        location: Location {
+                            uri: "file:///test/compiler/ty/select.rs",
+                            range: Range {
+                                start: Position {
+                                    line: 218,
+                                    character: 4,
+                                },
+                                end: Position {
+                                    line: 230,
+                                    character: 5,
+                                },
                             },
                         },
+                        message: "defined here",
                     },
-                    message: "defined here",
-                },
-            ],
-        ),
-        tags: None,
+                ],
+            ),
+            tags: None,
+        },
+        fixes: [],
     },
-    fixes: [],
-}
+]
diff --git a/crates/ra_cargo_watch/src/conv/test.rs b/crates/ra_cargo_watch/src/conv/test.rs
index 6b86525b8..4e81455ca 100644
--- a/crates/ra_cargo_watch/src/conv/test.rs
+++ b/crates/ra_cargo_watch/src/conv/test.rs
@@ -58,7 +58,7 @@ fn snap_rustc_incompatible_type_for_trait() {
     );
 
     let workspace_root = PathBuf::from("/test/");
-    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root).expect("couldn't map diagnostic");
+    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root);
     insta::assert_debug_snapshot!(diag);
 }
 
@@ -141,7 +141,7 @@ fn snap_rustc_unused_variable() {
     );
 
     let workspace_root = PathBuf::from("/test/");
-    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root).expect("couldn't map diagnostic");
+    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root);
     insta::assert_debug_snapshot!(diag);
 }
 
@@ -266,7 +266,7 @@ fn snap_rustc_wrong_number_of_parameters() {
     );
 
     let workspace_root = PathBuf::from("/test/");
-    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root).expect("couldn't map diagnostic");
+    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root);
     insta::assert_debug_snapshot!(diag);
 }
 
@@ -387,7 +387,7 @@ fn snap_clippy_pass_by_ref() {
     );
 
     let workspace_root = PathBuf::from("/test/");
-    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root).expect("couldn't map diagnostic");
+    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root);
     insta::assert_debug_snapshot!(diag);
 }
 
@@ -431,7 +431,7 @@ fn snap_rustc_mismatched_type() {
     );
 
     let workspace_root = PathBuf::from("/test/");
-    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root).expect("couldn't map diagnostic");
+    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root);
     insta::assert_debug_snapshot!(diag);
 }
 
@@ -703,7 +703,7 @@ fn snap_handles_macro_location() {
     );
 
     let workspace_root = PathBuf::from("/test/");
-    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root).expect("couldn't map diagnostic");
+    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root);
     insta::assert_debug_snapshot!(diag);
 }
 
@@ -933,6 +933,140 @@ fn snap_macro_compiler_error() {
     );
 
     let workspace_root = PathBuf::from("/test/");
-    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root).expect("couldn't map diagnostic");
+    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root);
+    insta::assert_debug_snapshot!(diag);
+}
+
+#[test]
+#[cfg(not(windows))]
+fn snap_multi_line_fix() {
+    let diag = parse_diagnostic(
+        r##"{
+            "rendered": "warning: returning the result of a let binding from a block\n --> src/main.rs:4:5\n  |\n3 |     let a = (0..10).collect();\n  |     -------------------------- unnecessary let binding\n4 |     a\n  |     ^\n  |\n  = note: `#[warn(clippy::let_and_return)]` on by default\n  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#let_and_return\nhelp: return the expression directly\n  |\n3 |     \n4 |     (0..10).collect()\n  |\n\n",
+            "children": [
+                {
+                "children": [],
+                "code": null,
+                "level": "note",
+                "message": "`#[warn(clippy::let_and_return)]` on by default",
+                "rendered": null,
+                "spans": []
+                },
+                {
+                "children": [],
+                "code": null,
+                "level": "help",
+                "message": "for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#let_and_return",
+                "rendered": null,
+                "spans": []
+                },
+                {
+                "children": [],
+                "code": null,
+                "level": "help",
+                "message": "return the expression directly",
+                "rendered": null,
+                "spans": [
+                    {
+                    "byte_end": 55,
+                    "byte_start": 29,
+                    "column_end": 31,
+                    "column_start": 5,
+                    "expansion": null,
+                    "file_name": "src/main.rs",
+                    "is_primary": true,
+                    "label": null,
+                    "line_end": 3,
+                    "line_start": 3,
+                    "suggested_replacement": "",
+                    "suggestion_applicability": "MachineApplicable",
+                    "text": [
+                        {
+                        "highlight_end": 31,
+                        "highlight_start": 5,
+                        "text": "    let a = (0..10).collect();"
+                        }
+                    ]
+                    },
+                    {
+                    "byte_end": 61,
+                    "byte_start": 60,
+                    "column_end": 6,
+                    "column_start": 5,
+                    "expansion": null,
+                    "file_name": "src/main.rs",
+                    "is_primary": true,
+                    "label": null,
+                    "line_end": 4,
+                    "line_start": 4,
+                    "suggested_replacement": "(0..10).collect()",
+                    "suggestion_applicability": "MachineApplicable",
+                    "text": [
+                        {
+                        "highlight_end": 6,
+                        "highlight_start": 5,
+                        "text": "    a"
+                        }
+                    ]
+                    }
+                ]
+                }
+            ],
+            "code": {
+                "code": "clippy::let_and_return",
+                "explanation": null
+            },
+            "level": "warning",
+            "message": "returning the result of a let binding from a block",
+            "spans": [
+                {
+                "byte_end": 55,
+                "byte_start": 29,
+                "column_end": 31,
+                "column_start": 5,
+                "expansion": null,
+                "file_name": "src/main.rs",
+                "is_primary": false,
+                "label": "unnecessary let binding",
+                "line_end": 3,
+                "line_start": 3,
+                "suggested_replacement": null,
+                "suggestion_applicability": null,
+                "text": [
+                    {
+                    "highlight_end": 31,
+                    "highlight_start": 5,
+                    "text": "    let a = (0..10).collect();"
+                    }
+                ]
+                },
+                {
+                "byte_end": 61,
+                "byte_start": 60,
+                "column_end": 6,
+                "column_start": 5,
+                "expansion": null,
+                "file_name": "src/main.rs",
+                "is_primary": true,
+                "label": null,
+                "line_end": 4,
+                "line_start": 4,
+                "suggested_replacement": null,
+                "suggestion_applicability": null,
+                "text": [
+                    {
+                    "highlight_end": 6,
+                    "highlight_start": 5,
+                    "text": "    a"
+                    }
+                ]
+                }
+            ]
+        }
+        "##,
+    );
+
+    let workspace_root = PathBuf::from("/test/");
+    let diag = map_rust_diagnostic_to_lsp(&diag, &workspace_root);
     insta::assert_debug_snapshot!(diag);
 }
diff --git a/crates/ra_cargo_watch/src/lib.rs b/crates/ra_cargo_watch/src/lib.rs
index f07c34549..94b9c03d0 100644
--- a/crates/ra_cargo_watch/src/lib.rs
+++ b/crates/ra_cargo_watch/src/lib.rs
@@ -197,23 +197,23 @@ impl CheckWatcherThread {
             }
 
             CheckEvent::Msg(Message::CompilerMessage(msg)) => {
-                let map_result =
-                    match map_rust_diagnostic_to_lsp(&msg.message, &self.workspace_root) {
-                        Some(map_result) => map_result,
-                        None => return,
-                    };
-
-                let MappedRustDiagnostic { location, diagnostic, fixes } = map_result;
-                let fixes = fixes
-                    .into_iter()
-                    .map(|fix| {
-                        CodeAction { diagnostics: Some(vec![diagnostic.clone()]), ..fix }.into()
-                    })
-                    .collect();
+                let map_result = map_rust_diagnostic_to_lsp(&msg.message, &self.workspace_root);
+                if map_result.is_empty() {
+                    return;
+                }
 
-                task_send
-                    .send(CheckTask::AddDiagnostic { url: location.uri, diagnostic, fixes })
-                    .unwrap();
+                for MappedRustDiagnostic { location, diagnostic, fixes } in map_result {
+                    let fixes = fixes
+                        .into_iter()
+                        .map(|fix| {
+                            CodeAction { diagnostics: Some(vec![diagnostic.clone()]), ..fix }.into()
+                        })
+                        .collect();
+
+                    task_send
+                        .send(CheckTask::AddDiagnostic { url: location.uri, diagnostic, fixes })
+                        .unwrap();
+                }
             }
 
             CheckEvent::Msg(Message::BuildScriptExecuted(_msg)) => {}
diff --git a/crates/ra_db/src/fixture.rs b/crates/ra_db/src/fixture.rs
index 7f43c2971..3dc86ca2d 100644
--- a/crates/ra_db/src/fixture.rs
+++ b/crates/ra_db/src/fixture.rs
@@ -61,7 +61,14 @@ fn with_single_file(db: &mut dyn SourceDatabaseExt, ra_fixture: &str) -> FileId
         };
 
         let mut crate_graph = CrateGraph::default();
-        crate_graph.add_crate_root(file_id, meta.edition, meta.krate, meta.cfg, meta.env);
+        crate_graph.add_crate_root(
+            file_id,
+            meta.edition,
+            meta.krate,
+            meta.cfg,
+            meta.env,
+            Default::default(),
+        );
         crate_graph
     } else {
         let mut crate_graph = CrateGraph::default();
@@ -71,6 +78,7 @@ fn with_single_file(db: &mut dyn SourceDatabaseExt, ra_fixture: &str) -> FileId
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         crate_graph
     };
@@ -119,6 +127,7 @@ fn with_files(db: &mut dyn SourceDatabaseExt, fixture: &str) -> Option<FilePosit
                 Some(krate.clone()),
                 meta.cfg,
                 meta.env,
+                Default::default(),
             );
             let prev = crates.insert(krate.clone(), crate_id);
             assert!(prev.is_none());
@@ -155,6 +164,7 @@ fn with_files(db: &mut dyn SourceDatabaseExt, fixture: &str) -> Option<FilePosit
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
     } else {
         for (from, to) in crate_deps {
diff --git a/crates/ra_db/src/input.rs b/crates/ra_db/src/input.rs
index 1a1c64202..06d40db96 100644
--- a/crates/ra_db/src/input.rs
+++ b/crates/ra_db/src/input.rs
@@ -113,6 +113,7 @@ pub struct CrateData {
     pub display_name: Option<String>,
     pub cfg_options: CfgOptions,
     pub env: Env,
+    pub extern_source: ExternSource,
     pub dependencies: Vec<Dependency>,
 }
 
@@ -122,11 +123,22 @@ pub enum Edition {
     Edition2015,
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct ExternSourceId(pub u32);
+
 #[derive(Default, Debug, Clone, PartialEq, Eq)]
 pub struct Env {
     entries: FxHashMap<String, String>,
 }
 
+// FIXME: Redesign vfs for solve the following limitation ?
+// Note: Some env variables (e.g. OUT_DIR) are located outside of the
+// crate. We store a map to allow remap it to ExternSourceId
+#[derive(Default, Debug, Clone, PartialEq, Eq)]
+pub struct ExternSource {
+    extern_paths: FxHashMap<String, ExternSourceId>,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Dependency {
     pub crate_id: CrateId,
@@ -141,6 +153,7 @@ impl CrateGraph {
         display_name: Option<String>,
         cfg_options: CfgOptions,
         env: Env,
+        extern_source: ExternSource,
     ) -> CrateId {
         let data = CrateData {
             root_file_id: file_id,
@@ -148,6 +161,7 @@ impl CrateGraph {
             display_name,
             cfg_options,
             env,
+            extern_source,
             dependencies: Vec::new(),
         };
         let crate_id = CrateId(self.arena.len() as u32);
@@ -271,6 +285,27 @@ impl Env {
     }
 }
 
+impl ExternSource {
+    pub fn extern_path(&self, path: &str) -> Option<(ExternSourceId, RelativePathBuf)> {
+        self.extern_paths.iter().find_map(|(root_path, id)| {
+            if path.starts_with(root_path) {
+                let mut rel_path = &path[root_path.len()..];
+                if rel_path.starts_with("/") {
+                    rel_path = &rel_path[1..];
+                }
+                let rel_path = RelativePathBuf::from_path(rel_path).ok()?;
+                Some((id.clone(), rel_path))
+            } else {
+                None
+            }
+        })
+    }
+
+    pub fn set_extern_path(&mut self, root_path: &str, root: ExternSourceId) {
+        self.extern_paths.insert(root_path.to_owned(), root);
+    }
+}
+
 #[derive(Debug)]
 pub struct ParseEditionError {
     invalid_input: String,
@@ -300,6 +335,7 @@ mod tests {
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         let crate2 = graph.add_crate_root(
             FileId(2u32),
@@ -307,6 +343,7 @@ mod tests {
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         let crate3 = graph.add_crate_root(
             FileId(3u32),
@@ -314,6 +351,7 @@ mod tests {
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         assert!(graph.add_dep(crate1, CrateName::new("crate2").unwrap(), crate2).is_ok());
         assert!(graph.add_dep(crate2, CrateName::new("crate3").unwrap(), crate3).is_ok());
@@ -329,6 +367,7 @@ mod tests {
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         let crate2 = graph.add_crate_root(
             FileId(2u32),
@@ -336,6 +375,7 @@ mod tests {
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         let crate3 = graph.add_crate_root(
             FileId(3u32),
@@ -343,6 +383,7 @@ mod tests {
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         assert!(graph.add_dep(crate1, CrateName::new("crate2").unwrap(), crate2).is_ok());
         assert!(graph.add_dep(crate2, CrateName::new("crate3").unwrap(), crate3).is_ok());
@@ -357,6 +398,7 @@ mod tests {
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         let crate2 = graph.add_crate_root(
             FileId(2u32),
@@ -364,6 +406,7 @@ mod tests {
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         assert!(graph
             .add_dep(crate1, CrateName::normalize_dashes("crate-name-with-dashes"), crate2)
diff --git a/crates/ra_db/src/lib.rs b/crates/ra_db/src/lib.rs
index fb002d717..d500d5e85 100644
--- a/crates/ra_db/src/lib.rs
+++ b/crates/ra_db/src/lib.rs
@@ -11,7 +11,8 @@ use ra_syntax::{ast, Parse, SourceFile, TextRange, TextUnit};
 pub use crate::{
     cancellation::Canceled,
     input::{
-        CrateGraph, CrateId, CrateName, Dependency, Edition, Env, FileId, SourceRoot, SourceRootId,
+        CrateGraph, CrateId, CrateName, Dependency, Edition, Env, ExternSource, ExternSourceId,
+        FileId, SourceRoot, SourceRootId,
     },
 };
 pub use relative_path::{RelativePath, RelativePathBuf};
@@ -87,6 +88,12 @@ pub trait FileLoader {
     fn resolve_relative_path(&self, anchor: FileId, relative_path: &RelativePath)
         -> Option<FileId>;
     fn relevant_crates(&self, file_id: FileId) -> Arc<Vec<CrateId>>;
+
+    fn resolve_extern_path(
+        &self,
+        extern_id: ExternSourceId,
+        relative_path: &RelativePath,
+    ) -> Option<FileId>;
 }
 
 /// Database which stores all significant input facts: source code and project
@@ -164,4 +171,13 @@ impl<T: SourceDatabaseExt> FileLoader for FileLoaderDelegate<&'_ T> {
         let source_root = self.0.file_source_root(file_id);
         self.0.source_root_crates(source_root)
     }
+
+    fn resolve_extern_path(
+        &self,
+        extern_id: ExternSourceId,
+        relative_path: &RelativePath,
+    ) -> Option<FileId> {
+        let source_root = self.0.source_root(SourceRootId(extern_id.0));
+        source_root.file_by_relative_path(&relative_path)
+    }
 }
diff --git a/crates/ra_hir_def/src/test_db.rs b/crates/ra_hir_def/src/test_db.rs
index 1568820e9..0756916a8 100644
--- a/crates/ra_hir_def/src/test_db.rs
+++ b/crates/ra_hir_def/src/test_db.rs
@@ -6,7 +6,7 @@ use std::{
 };
 
 use crate::db::DefDatabase;
-use ra_db::{salsa, CrateId, FileId, FileLoader, FileLoaderDelegate, RelativePath};
+use ra_db::{salsa, CrateId, ExternSourceId, FileId, FileLoader, FileLoaderDelegate, RelativePath};
 
 #[salsa::database(
     ra_db::SourceDatabaseExtStorage,
@@ -52,6 +52,14 @@ impl FileLoader for TestDB {
     fn relevant_crates(&self, file_id: FileId) -> Arc<Vec<CrateId>> {
         FileLoaderDelegate(self).relevant_crates(file_id)
     }
+
+    fn resolve_extern_path(
+        &self,
+        extern_id: ExternSourceId,
+        relative_path: &RelativePath,
+    ) -> Option<FileId> {
+        FileLoaderDelegate(self).resolve_extern_path(extern_id, relative_path)
+    }
 }
 
 impl TestDB {
diff --git a/crates/ra_hir_expand/src/builtin_macro.rs b/crates/ra_hir_expand/src/builtin_macro.rs
index 3f60b1cca..f9d3787f6 100644
--- a/crates/ra_hir_expand/src/builtin_macro.rs
+++ b/crates/ra_hir_expand/src/builtin_macro.rs
@@ -88,17 +88,18 @@ register_builtin! {
     (compile_error, CompileError) => compile_error_expand,
     (file, File) => file_expand,
     (line, Line) => line_expand,
+    (assert, Assert) => assert_expand,
     (stringify, Stringify) => stringify_expand,
     (format_args, FormatArgs) => format_args_expand,
-    (env, Env) => env_expand,
-    (option_env, OptionEnv) => option_env_expand,
     // format_args_nl only differs in that it adds a newline in the end,
     // so we use the same stub expansion for now
     (format_args_nl, FormatArgsNl) => format_args_expand,
 
     EAGER:
     (concat, Concat) => concat_expand,
-    (include, Include) => include_expand
+    (include, Include) => include_expand,
+    (env, Env) => env_expand,
+    (option_env, OptionEnv) => option_env_expand
 }
 
 fn line_expand(
@@ -137,42 +138,56 @@ fn stringify_expand(
     Ok(expanded)
 }
 
-fn env_expand(
+fn column_expand(
     _db: &dyn AstDatabase,
     _id: LazyMacroId,
     _tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     // dummy implementation for type-checking purposes
-    // we cannot use an empty string here, because for
-    // `include!(concat!(env!("OUT_DIR"), "/foo.rs"))` will become
-    // `include!("foo.rs"), which maybe infinite loop
-    let expanded = quote! { "__RA_UNIMPLEMENTATED__" };
+    let col_num = 0;
+    let expanded = quote! {
+        #col_num
+    };
 
     Ok(expanded)
 }
 
-fn option_env_expand(
+fn assert_expand(
     _db: &dyn AstDatabase,
     _id: LazyMacroId,
-    _tt: &tt::Subtree,
+    tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
-    // dummy implementation for type-checking purposes
-    let expanded = quote! { std::option::Option::None::<&str> };
+    // A hacky implementation for goto def and hover
+    // We expand `assert!(cond, arg1, arg2)` to
+    // ```
+    // {(cond, &(arg1), &(arg2));}
+    // ```,
+    // which is wrong but useful.
 
-    Ok(expanded)
-}
+    let mut args = Vec::new();
+    let mut current = Vec::new();
+    for tt in tt.token_trees.iter().cloned() {
+        match tt {
+            tt::TokenTree::Leaf(tt::Leaf::Punct(p)) if p.char == ',' => {
+                args.push(current);
+                current = Vec::new();
+            }
+            _ => {
+                current.push(tt);
+            }
+        }
+    }
+    if !current.is_empty() {
+        args.push(current);
+    }
+
+    let arg_tts = args.into_iter().flat_map(|arg| {
+        quote! { &(##arg), }
+    }.token_trees).collect::<Vec<_>>();
 
-fn column_expand(
-    _db: &dyn AstDatabase,
-    _id: LazyMacroId,
-    _tt: &tt::Subtree,
-) -> Result<tt::Subtree, mbe::ExpandError> {
-    // dummy implementation for type-checking purposes
-    let col_num = 0;
     let expanded = quote! {
-        #col_num
+        { { (##arg_tts); } }
     };
-
     Ok(expanded)
 }
 
@@ -278,30 +293,37 @@ fn concat_expand(
 
 fn relative_file(db: &dyn AstDatabase, call_id: MacroCallId, path: &str) -> Option<FileId> {
     let call_site = call_id.as_file().original_file(db);
-    let path = RelativePath::new(&path);
 
-    let res = db.resolve_relative_path(call_site, &path)?;
-    // Prevent include itself
-    if res == call_site {
-        return None;
+    // Handle trivial case
+    if let Some(res) = db.resolve_relative_path(call_site, &RelativePath::new(&path)) {
+        // Prevent include itself
+        return if res == call_site { None } else { Some(res) };
     }
-    Some(res)
+
+    // Extern paths ?
+    let krate = db.relevant_crates(call_site).get(0)?.clone();
+    let (extern_source_id, relative_file) =
+        db.crate_graph()[krate].extern_source.extern_path(path)?;
+
+    db.resolve_extern_path(extern_source_id, &relative_file)
 }
 
-fn include_expand(
-    db: &dyn AstDatabase,
-    arg_id: EagerMacroId,
-    tt: &tt::Subtree,
-) -> Result<(tt::Subtree, FragmentKind), mbe::ExpandError> {
-    let path = tt
-        .token_trees
+fn parse_string(tt: &tt::Subtree) -> Result<String, mbe::ExpandError> {
+    tt.token_trees
         .get(0)
         .and_then(|tt| match tt {
             tt::TokenTree::Leaf(tt::Leaf::Literal(it)) => unquote_str(&it),
             _ => None,
         })
-        .ok_or_else(|| mbe::ExpandError::ConversionError)?;
+        .ok_or_else(|| mbe::ExpandError::ConversionError)
+}
 
+fn include_expand(
+    db: &dyn AstDatabase,
+    arg_id: EagerMacroId,
+    tt: &tt::Subtree,
+) -> Result<(tt::Subtree, FragmentKind), mbe::ExpandError> {
+    let path = parse_string(tt)?;
     let file_id =
         relative_file(db, arg_id.into(), &path).ok_or_else(|| mbe::ExpandError::ConversionError)?;
 
@@ -314,12 +336,58 @@ fn include_expand(
     Ok((res, FragmentKind::Items))
 }
 
+fn get_env_inner(db: &dyn AstDatabase, arg_id: EagerMacroId, key: &str) -> Option<String> {
+    let call_id: MacroCallId = arg_id.into();
+    let original_file = call_id.as_file().original_file(db);
+
+    let krate = db.relevant_crates(original_file).get(0)?.clone();
+    db.crate_graph()[krate].env.get(key)
+}
+
+fn env_expand(
+    db: &dyn AstDatabase,
+    arg_id: EagerMacroId,
+    tt: &tt::Subtree,
+) -> Result<(tt::Subtree, FragmentKind), mbe::ExpandError> {
+    let key = parse_string(tt)?;
+
+    // FIXME:
+    // If the environment variable is not defined int rustc, then a compilation error will be emitted.
+    // We might do the same if we fully support all other stuffs.
+    // But for now on, we should return some dummy string for better type infer purpose.
+    // However, we cannot use an empty string here, because for
+    // `include!(concat!(env!("OUT_DIR"), "/foo.rs"))` will become
+    // `include!("foo.rs"), which might go to infinite loop
+    let s = get_env_inner(db, arg_id, &key).unwrap_or("__RA_UNIMPLEMENTATED__".to_string());
+    let expanded = quote! { #s };
+
+    Ok((expanded, FragmentKind::Expr))
+}
+
+fn option_env_expand(
+    db: &dyn AstDatabase,
+    arg_id: EagerMacroId,
+    tt: &tt::Subtree,
+) -> Result<(tt::Subtree, FragmentKind), mbe::ExpandError> {
+    let key = parse_string(tt)?;
+    let expanded = match get_env_inner(db, arg_id, &key) {
+        None => quote! { std::option::Option::None::<&str> },
+        Some(s) => quote! { std::option::Some(#s) },
+    };
+
+    Ok((expanded, FragmentKind::Expr))
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::{name::AsName, test_db::TestDB, AstNode, MacroCallId, MacroCallKind, MacroCallLoc};
+    use crate::{
+        name::AsName, test_db::TestDB, AstNode, EagerCallLoc, MacroCallId, MacroCallKind,
+        MacroCallLoc,
+    };
     use ra_db::{fixture::WithFixture, SourceDatabase};
     use ra_syntax::ast::NameOwner;
+    use std::sync::Arc;
 
     fn expand_builtin_macro(ra_fixture: &str) -> String {
         let (db, file_id) = TestDB::with_single_file(&ra_fixture);
@@ -330,27 +398,61 @@ mod tests {
         let ast_id_map = db.ast_id_map(file_id.into());
 
         let expander = find_by_name(&macro_calls[0].name().unwrap().as_name()).unwrap();
-        let expander = expander.left().unwrap();
 
-        // the first one should be a macro_rules
-        let def = MacroDefId {
-            krate: Some(CrateId(0)),
-            ast_id: Some(AstId::new(file_id.into(), ast_id_map.ast_id(&macro_calls[0]))),
-            kind: MacroDefKind::BuiltIn(expander),
-        };
+        let file_id = match expander {
+            Either::Left(expander) => {
+                // the first one should be a macro_rules
+                let def = MacroDefId {
+                    krate: Some(CrateId(0)),
+                    ast_id: Some(AstId::new(file_id.into(), ast_id_map.ast_id(&macro_calls[0]))),
+                    kind: MacroDefKind::BuiltIn(expander),
+                };
 
-        let loc = MacroCallLoc {
-            def,
-            kind: MacroCallKind::FnLike(AstId::new(
-                file_id.into(),
-                ast_id_map.ast_id(&macro_calls[1]),
-            )),
-        };
+                let loc = MacroCallLoc {
+                    def,
+                    kind: MacroCallKind::FnLike(AstId::new(
+                        file_id.into(),
+                        ast_id_map.ast_id(&macro_calls[1]),
+                    )),
+                };
+
+                let id: MacroCallId = db.intern_macro(loc).into();
+                id.as_file()
+            }
+            Either::Right(expander) => {
+                // the first one should be a macro_rules
+                let def = MacroDefId {
+                    krate: Some(CrateId(0)),
+                    ast_id: Some(AstId::new(file_id.into(), ast_id_map.ast_id(&macro_calls[0]))),
+                    kind: MacroDefKind::BuiltInEager(expander),
+                };
 
-        let id: MacroCallId = db.intern_macro(loc).into();
-        let parsed = db.parse_or_expand(id.as_file()).unwrap();
+                let args = macro_calls[1].token_tree().unwrap();
+                let parsed_args = mbe::ast_to_token_tree(&args).unwrap().0;
+
+                let arg_id = db.intern_eager_expansion({
+                    EagerCallLoc {
+                        def,
+                        fragment: FragmentKind::Expr,
+                        subtree: Arc::new(parsed_args.clone()),
+                        file_id: file_id.into(),
+                    }
+                });
+
+                let (subtree, fragment) = expander.expand(&db, arg_id, &parsed_args).unwrap();
+                let eager = EagerCallLoc {
+                    def,
+                    fragment,
+                    subtree: Arc::new(subtree),
+                    file_id: file_id.into(),
+                };
 
-        parsed.text().to_string()
+                let id: MacroCallId = db.intern_eager_expansion(eager.into()).into();
+                id.as_file()
+            }
+        };
+
+        db.parse_or_expand(file_id).unwrap().to_string()
     }
 
     #[test]
@@ -432,6 +534,22 @@ mod tests {
     }
 
     #[test]
+    fn test_assert_expand() {
+        let expanded = expand_builtin_macro(
+            r#"
+            #[rustc_builtin_macro]
+            macro_rules! assert {
+                ($cond:expr) => ({ /* compiler built-in */ });
+                ($cond:expr, $($args:tt)*) => ({ /* compiler built-in */ })
+            }
+            assert!(true, "{} {:?}", arg1(a, b, c), arg2);
+            "#,
+        );
+
+        assert_eq!(expanded, "{{(&(true), &(\"{} {:?}\"), &(arg1(a,b,c)), &(arg2),);}}");
+    }
+
+    #[test]
     fn test_compile_error_expand() {
         let expanded = expand_builtin_macro(
             r#"
diff --git a/crates/ra_hir_expand/src/name.rs b/crates/ra_hir_expand/src/name.rs
index 6d201256f..25cc1e9fc 100644
--- a/crates/ra_hir_expand/src/name.rs
+++ b/crates/ra_hir_expand/src/name.rs
@@ -172,6 +172,7 @@ pub mod known {
         column,
         compile_error,
         line,
+        assert,
         stringify,
         concat,
         include,
diff --git a/crates/ra_hir_expand/src/quote.rs b/crates/ra_hir_expand/src/quote.rs
index 57e7eebf9..3fd4233da 100644
--- a/crates/ra_hir_expand/src/quote.rs
+++ b/crates/ra_hir_expand/src/quote.rs
@@ -99,6 +99,7 @@ macro_rules! __quote {
     ( & ) => {$crate::__quote!(@PUNCT '&')};
     ( , ) => {$crate::__quote!(@PUNCT ',')};
     ( : ) => {$crate::__quote!(@PUNCT ':')};
+    ( ; ) => {$crate::__quote!(@PUNCT ';')};
     ( :: ) => {$crate::__quote!(@PUNCT ':', ':')};
     ( . ) => {$crate::__quote!(@PUNCT '.')};
     ( < ) => {$crate::__quote!(@PUNCT '<')};
diff --git a/crates/ra_hir_expand/src/test_db.rs b/crates/ra_hir_expand/src/test_db.rs
index 918736e2a..c1fb762de 100644
--- a/crates/ra_hir_expand/src/test_db.rs
+++ b/crates/ra_hir_expand/src/test_db.rs
@@ -5,7 +5,7 @@ use std::{
     sync::{Arc, Mutex},
 };
 
-use ra_db::{salsa, CrateId, FileId, FileLoader, FileLoaderDelegate, RelativePath};
+use ra_db::{salsa, CrateId, ExternSourceId, FileId, FileLoader, FileLoaderDelegate, RelativePath};
 
 #[salsa::database(
     ra_db::SourceDatabaseExtStorage,
@@ -51,4 +51,11 @@ impl FileLoader for TestDB {
     fn relevant_crates(&self, file_id: FileId) -> Arc<Vec<CrateId>> {
         FileLoaderDelegate(self).relevant_crates(file_id)
     }
+    fn resolve_extern_path(
+        &self,
+        anchor: ExternSourceId,
+        relative_path: &RelativePath,
+    ) -> Option<FileId> {
+        FileLoaderDelegate(self).resolve_extern_path(anchor, relative_path)
+    }
 }
diff --git a/crates/ra_hir_ty/src/test_db.rs b/crates/ra_hir_ty/src/test_db.rs
index c794f7b84..0be2fea4b 100644
--- a/crates/ra_hir_ty/src/test_db.rs
+++ b/crates/ra_hir_ty/src/test_db.rs
@@ -67,6 +67,13 @@ impl FileLoader for TestDB {
     fn relevant_crates(&self, file_id: FileId) -> Arc<Vec<CrateId>> {
         FileLoaderDelegate(self).relevant_crates(file_id)
     }
+    fn resolve_extern_path(
+        &self,
+        extern_id: ra_db::ExternSourceId,
+        relative_path: &RelativePath,
+    ) -> Option<FileId> {
+        FileLoaderDelegate(self).resolve_extern_path(extern_id, relative_path)
+    }
 }
 
 impl TestDB {
diff --git a/crates/ra_hir_ty/src/tests/macros.rs b/crates/ra_hir_ty/src/tests/macros.rs
index ffa78b046..32457bbf7 100644
--- a/crates/ra_hir_ty/src/tests/macros.rs
+++ b/crates/ra_hir_ty/src/tests/macros.rs
@@ -550,6 +550,26 @@ fn main() {
 }
 
 #[test]
+fn infer_builtin_macros_env() {
+    assert_snapshot!(
+        infer(r#"
+//- /main.rs env:foo=bar
+#[rustc_builtin_macro]
+macro_rules! env {() => {}}
+
+fn main() {
+    let x = env!("foo");
+}
+"#),
+        @r###"
+    ![0; 5) '"bar"': &str
+    [88; 116) '{     ...o"); }': ()
+    [98; 99) 'x': &str
+    "###
+    );
+}
+
+#[test]
 fn infer_derive_clone_simple() {
     let (db, pos) = TestDB::with_position(
         r#"
diff --git a/crates/ra_ide/src/completion.rs b/crates/ra_ide/src/completion.rs
index a27e0fc15..93e53c921 100644
--- a/crates/ra_ide/src/completion.rs
+++ b/crates/ra_ide/src/completion.rs
@@ -16,11 +16,11 @@ mod complete_scope;
 mod complete_postfix;
 mod complete_macro_in_item_position;
 mod complete_trait_impl;
+#[cfg(test)]
+mod test_utils;
 
 use ra_ide_db::RootDatabase;
 
-#[cfg(test)]
-use crate::completion::completion_item::do_completion;
 use crate::{
     completion::{
         completion_context::CompletionContext,
diff --git a/crates/ra_ide/src/completion/complete_dot.rs b/crates/ra_ide/src/completion/complete_dot.rs
index d8f6f0d9d..81e5037aa 100644
--- a/crates/ra_ide/src/completion/complete_dot.rs
+++ b/crates/ra_ide/src/completion/complete_dot.rs
@@ -70,7 +70,7 @@ fn complete_methods(acc: &mut Completions, ctx: &CompletionContext, receiver: &T
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
     fn do_ref_completion(code: &str) -> Vec<CompletionItem> {
diff --git a/crates/ra_ide/src/completion/complete_fn_param.rs b/crates/ra_ide/src/completion/complete_fn_param.rs
index 502458706..9226ac055 100644
--- a/crates/ra_ide/src/completion/complete_fn_param.rs
+++ b/crates/ra_ide/src/completion/complete_fn_param.rs
@@ -52,7 +52,7 @@ pub(super) fn complete_fn_param(acc: &mut Completions, ctx: &CompletionContext)
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
     fn do_magic_completion(code: &str) -> Vec<CompletionItem> {
diff --git a/crates/ra_ide/src/completion/complete_keyword.rs b/crates/ra_ide/src/completion/complete_keyword.rs
index e1c0ffb1f..1e053ea4a 100644
--- a/crates/ra_ide/src/completion/complete_keyword.rs
+++ b/crates/ra_ide/src/completion/complete_keyword.rs
@@ -117,7 +117,7 @@ fn complete_return(
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
     fn do_keyword_completion(code: &str) -> Vec<CompletionItem> {
diff --git a/crates/ra_ide/src/completion/complete_macro_in_item_position.rs b/crates/ra_ide/src/completion/complete_macro_in_item_position.rs
index 1866d9e6c..270e96df0 100644
--- a/crates/ra_ide/src/completion/complete_macro_in_item_position.rs
+++ b/crates/ra_ide/src/completion/complete_macro_in_item_position.rs
@@ -15,9 +15,10 @@ pub(super) fn complete_macro_in_item_position(acc: &mut Completions, ctx: &Compl
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
+
     fn do_reference_completion(code: &str) -> Vec<CompletionItem> {
         do_completion(code, CompletionKind::Reference)
     }
diff --git a/crates/ra_ide/src/completion/complete_path.rs b/crates/ra_ide/src/completion/complete_path.rs
index 3c4a70561..d588ee364 100644
--- a/crates/ra_ide/src/completion/complete_path.rs
+++ b/crates/ra_ide/src/completion/complete_path.rs
@@ -103,7 +103,7 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
 mod tests {
     use test_utils::covers;
 
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
     fn do_reference_completion(code: &str) -> Vec<CompletionItem> {
diff --git a/crates/ra_ide/src/completion/complete_pattern.rs b/crates/ra_ide/src/completion/complete_pattern.rs
index fa8aeceda..6a1a66ef1 100644
--- a/crates/ra_ide/src/completion/complete_pattern.rs
+++ b/crates/ra_ide/src/completion/complete_pattern.rs
@@ -27,7 +27,7 @@ pub(super) fn complete_pattern(acc: &mut Completions, ctx: &CompletionContext) {
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
     fn complete(code: &str) -> Vec<CompletionItem> {
diff --git a/crates/ra_ide/src/completion/complete_postfix.rs b/crates/ra_ide/src/completion/complete_postfix.rs
index 6d000548d..0ba382165 100644
--- a/crates/ra_ide/src/completion/complete_postfix.rs
+++ b/crates/ra_ide/src/completion/complete_postfix.rs
@@ -81,7 +81,7 @@ fn postfix_snippet(ctx: &CompletionContext, label: &str, detail: &str, snippet:
 mod tests {
     use insta::assert_debug_snapshot;
 
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
 
     fn do_postfix_completion(code: &str) -> Vec<CompletionItem> {
         do_completion(code, CompletionKind::Postfix)
diff --git a/crates/ra_ide/src/completion/complete_record_literal.rs b/crates/ra_ide/src/completion/complete_record_literal.rs
index be6e4194f..83ed1d52c 100644
--- a/crates/ra_ide/src/completion/complete_record_literal.rs
+++ b/crates/ra_ide/src/completion/complete_record_literal.rs
@@ -18,7 +18,7 @@ pub(super) fn complete_record_literal(acc: &mut Completions, ctx: &CompletionCon
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
     fn complete(code: &str) -> Vec<CompletionItem> {
diff --git a/crates/ra_ide/src/completion/complete_record_pattern.rs b/crates/ra_ide/src/completion/complete_record_pattern.rs
index 687c57d3e..962376428 100644
--- a/crates/ra_ide/src/completion/complete_record_pattern.rs
+++ b/crates/ra_ide/src/completion/complete_record_pattern.rs
@@ -17,7 +17,7 @@ pub(super) fn complete_record_pattern(acc: &mut Completions, ctx: &CompletionCon
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
     fn complete(code: &str) -> Vec<CompletionItem> {
diff --git a/crates/ra_ide/src/completion/complete_scope.rs b/crates/ra_ide/src/completion/complete_scope.rs
index eb3c8cf1b..bd4adf23a 100644
--- a/crates/ra_ide/src/completion/complete_scope.rs
+++ b/crates/ra_ide/src/completion/complete_scope.rs
@@ -14,10 +14,10 @@ pub(super) fn complete_scope(acc: &mut Completions, ctx: &CompletionContext) {
 mod tests {
     use insta::assert_debug_snapshot;
 
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
 
-    fn do_reference_completion(code: &str) -> Vec<CompletionItem> {
-        do_completion(code, CompletionKind::Reference)
+    fn do_reference_completion(ra_fixture: &str) -> Vec<CompletionItem> {
+        do_completion(ra_fixture, CompletionKind::Reference)
     }
 
     #[test]
diff --git a/crates/ra_ide/src/completion/complete_snippet.rs b/crates/ra_ide/src/completion/complete_snippet.rs
index 731b4fd82..f731e9b9a 100644
--- a/crates/ra_ide/src/completion/complete_snippet.rs
+++ b/crates/ra_ide/src/completion/complete_snippet.rs
@@ -42,7 +42,7 @@ fn ${1:feature}() {
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
     fn do_snippet_completion(code: &str) -> Vec<CompletionItem> {
diff --git a/crates/ra_ide/src/completion/complete_trait_impl.rs b/crates/ra_ide/src/completion/complete_trait_impl.rs
index 2bf654a57..7fefa2c7a 100644
--- a/crates/ra_ide/src/completion/complete_trait_impl.rs
+++ b/crates/ra_ide/src/completion/complete_trait_impl.rs
@@ -217,7 +217,7 @@ fn make_const_compl_syntax(const_: &ast::ConstDef) -> String {
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
     use insta::assert_debug_snapshot;
 
     fn complete(code: &str) -> Vec<CompletionItem> {
diff --git a/crates/ra_ide/src/completion/completion_item.rs b/crates/ra_ide/src/completion/completion_item.rs
index 1d14e9636..ef0eb43b2 100644
--- a/crates/ra_ide/src/completion/completion_item.rs
+++ b/crates/ra_ide/src/completion/completion_item.rs
@@ -13,7 +13,7 @@ pub struct CompletionItem {
     /// Used only internally in tests, to check only specific kind of
     /// completion (postfix, keyword, reference, etc).
     #[allow(unused)]
-    completion_kind: CompletionKind,
+    pub(crate) completion_kind: CompletionKind,
     /// Label in the completion pop up which identifies completion.
     label: String,
     /// Range of identifier that is being completed.
@@ -318,24 +318,3 @@ impl Into<Vec<CompletionItem>> for Completions {
         self.buf
     }
 }
-
-#[cfg(test)]
-pub(crate) fn do_completion(code: &str, kind: CompletionKind) -> Vec<CompletionItem> {
-    use crate::{
-        completion::{completions, CompletionOptions},
-        mock_analysis::{analysis_and_position, single_file_with_position},
-    };
-
-    let (analysis, position) = if code.contains("//-") {
-        analysis_and_position(code)
-    } else {
-        single_file_with_position(code)
-    };
-    let options = CompletionOptions::default();
-    let completions = completions(&analysis.db, position, &options).unwrap();
-    let completion_items: Vec<CompletionItem> = completions.into();
-    let mut kind_completions: Vec<CompletionItem> =
-        completion_items.into_iter().filter(|c| c.completion_kind == kind).collect();
-    kind_completions.sort_by_key(|c| c.label.clone());
-    kind_completions
-}
diff --git a/crates/ra_ide/src/completion/presentation.rs b/crates/ra_ide/src/completion/presentation.rs
index 3dc56e4a3..5213def20 100644
--- a/crates/ra_ide/src/completion/presentation.rs
+++ b/crates/ra_ide/src/completion/presentation.rs
@@ -307,12 +307,22 @@ mod tests {
     use insta::assert_debug_snapshot;
     use test_utils::covers;
 
-    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use crate::completion::{
+        test_utils::{do_completion, do_completion_with_options},
+        CompletionItem, CompletionKind, CompletionOptions,
+    };
 
     fn do_reference_completion(ra_fixture: &str) -> Vec<CompletionItem> {
         do_completion(ra_fixture, CompletionKind::Reference)
     }
 
+    fn do_reference_completion_with_options(
+        ra_fixture: &str,
+        options: CompletionOptions,
+    ) -> Vec<CompletionItem> {
+        do_completion_with_options(ra_fixture, CompletionKind::Reference, &options)
+    }
+
     #[test]
     fn enum_detail_includes_names_for_record() {
         assert_debug_snapshot!(
@@ -533,7 +543,7 @@ mod tests {
     }
 
     #[test]
-    fn parens_for_method_call() {
+    fn arg_snippets_for_method_call() {
         assert_debug_snapshot!(
             do_reference_completion(
                 r"
@@ -563,6 +573,40 @@ mod tests {
     }
 
     #[test]
+    fn no_arg_snippets_for_method_call() {
+        assert_debug_snapshot!(
+            do_reference_completion_with_options(
+                r"
+                struct S {}
+                impl S {
+                    fn foo(&self, x: i32) {}
+                }
+                fn bar(s: &S) {
+                    s.f<|>
+                }
+                ",
+                CompletionOptions {
+                    add_call_argument_snippets: false,
+                    .. Default::default()
+                }
+            ),
+            @r###"
+        [
+            CompletionItem {
+                label: "foo(…)",
+                source_range: [171; 172),
+                delete: [171; 172),
+                insert: "foo($0)",
+                kind: Method,
+                lookup: "foo",
+                detail: "fn foo(&self, x: i32)",
+            },
+        ]
+        "###
+        )
+    }
+
+    #[test]
     fn dont_render_function_parens_in_use_item() {
         assert_debug_snapshot!(
             do_reference_completion(
diff --git a/crates/ra_ide/src/completion/test_utils.rs b/crates/ra_ide/src/completion/test_utils.rs
new file mode 100644
index 000000000..136857315
--- /dev/null
+++ b/crates/ra_ide/src/completion/test_utils.rs
@@ -0,0 +1,29 @@
+//! Runs completion for testing purposes.
+
+use crate::{
+    completion::{completion_item::CompletionKind, CompletionOptions},
+    mock_analysis::{analysis_and_position, single_file_with_position},
+    CompletionItem,
+};
+
+pub(crate) fn do_completion(code: &str, kind: CompletionKind) -> Vec<CompletionItem> {
+    do_completion_with_options(code, kind, &CompletionOptions::default())
+}
+
+pub(crate) fn do_completion_with_options(
+    code: &str,
+    kind: CompletionKind,
+    options: &CompletionOptions,
+) -> Vec<CompletionItem> {
+    let (analysis, position) = if code.contains("//-") {
+        analysis_and_position(code)
+    } else {
+        single_file_with_position(code)
+    };
+    let completions = analysis.completions(position, options).unwrap().unwrap();
+    let completion_items: Vec<CompletionItem> = completions.into();
+    let mut kind_completions: Vec<CompletionItem> =
+        completion_items.into_iter().filter(|c| c.completion_kind == kind).collect();
+    kind_completions.sort_by_key(|c| c.label().to_owned());
+    kind_completions
+}
diff --git a/crates/ra_ide/src/hover.rs b/crates/ra_ide/src/hover.rs
index 25e038a55..0bbba4855 100644
--- a/crates/ra_ide/src/hover.rs
+++ b/crates/ra_ide/src/hover.rs
@@ -833,19 +833,34 @@ fn func(foo: i32) { if true { <|>foo; }; }
     }
 
     #[test]
+    fn test_hover_through_assert_macro() {
+        let hover_on = check_hover_result(
+            r#"
+            //- /lib.rs
+            #[rustc_builtin_macro]
+            macro_rules! assert {}
+
+            fn bar() -> bool { true }
+            fn foo() {
+                assert!(ba<|>r());
+            }
+            "#,
+            &["fn bar() -> bool"],
+        );
+
+        assert_eq!(hover_on, "bar");
+    }
+
+    #[test]
     fn test_hover_through_literal_string_in_builtin_macro() {
         check_hover_no_result(
             r#"
             //- /lib.rs
             #[rustc_builtin_macro]
-            macro_rules! assert {
-                ($cond:expr) => {{ /* compiler built-in */ }};
-                ($cond:expr,) => {{ /* compiler built-in */ }};
-                ($cond:expr, $($arg:tt)+) => {{ /* compiler built-in */ }};
-            }
+            macro_rules! format {}
 
             fn foo() {
-                assert!("hel<|>lo");
+                format!("hel<|>lo {}", 0);
             }
             "#,
         );
diff --git a/crates/ra_ide/src/lib.rs b/crates/ra_ide/src/lib.rs
index a3acfd225..922e4caa8 100644
--- a/crates/ra_ide/src/lib.rs
+++ b/crates/ra_ide/src/lib.rs
@@ -212,6 +212,7 @@ impl Analysis {
             None,
             cfg_options,
             Env::default(),
+            Default::default(),
         );
         change.add_file(source_root, file_id, "main.rs".into(), Arc::new(text));
         change.set_crate_graph(crate_graph);
diff --git a/crates/ra_ide/src/mock_analysis.rs b/crates/ra_ide/src/mock_analysis.rs
index 90f84b052..25816cf6f 100644
--- a/crates/ra_ide/src/mock_analysis.rs
+++ b/crates/ra_ide/src/mock_analysis.rs
@@ -102,6 +102,7 @@ impl MockAnalysis {
                     None,
                     cfg_options,
                     Env::default(),
+                    Default::default(),
                 ));
             } else if path.ends_with("/lib.rs") {
                 let crate_name = path.parent().unwrap().file_name().unwrap();
@@ -111,6 +112,7 @@ impl MockAnalysis {
                     Some(crate_name.to_owned()),
                     cfg_options,
                     Env::default(),
+                    Default::default(),
                 );
                 if let Some(root_crate) = root_crate {
                     crate_graph
diff --git a/crates/ra_ide/src/parent_module.rs b/crates/ra_ide/src/parent_module.rs
index b73cefd97..76d130b9b 100644
--- a/crates/ra_ide/src/parent_module.rs
+++ b/crates/ra_ide/src/parent_module.rs
@@ -136,6 +136,7 @@ mod tests {
             None,
             CfgOptions::default(),
             Env::default(),
+            Default::default(),
         );
         let mut change = AnalysisChange::new();
         change.set_crate_graph(crate_graph);
diff --git a/crates/ra_ide/src/references/rename.rs b/crates/ra_ide/src/references/rename.rs
index 5b4bcf434..7d1190af9 100644
--- a/crates/ra_ide/src/references/rename.rs
+++ b/crates/ra_ide/src/references/rename.rs
@@ -9,7 +9,8 @@ use ra_syntax::{
 use ra_text_edit::TextEdit;
 
 use crate::{
-    FileId, FilePosition, FileSystemEdit, RangeInfo, SourceChange, SourceFileEdit, TextRange,
+    FilePosition, FileSystemEdit, RangeInfo, Reference, ReferenceKind, SourceChange,
+    SourceFileEdit, TextRange,
 };
 
 use super::find_all_refs;
@@ -46,12 +47,29 @@ fn find_name_and_module_at_offset(
     Some((ast_name, ast_module))
 }
 
-fn source_edit_from_file_id_range(
-    file_id: FileId,
-    range: TextRange,
-    new_name: &str,
-) -> SourceFileEdit {
-    SourceFileEdit { file_id, edit: TextEdit::replace(range, new_name.into()) }
+fn source_edit_from_reference(reference: Reference, new_name: &str) -> SourceFileEdit {
+    let mut replacement_text = String::new();
+    let file_id = reference.file_range.file_id;
+    let range = match reference.kind {
+        ReferenceKind::StructFieldShorthandForField => {
+            replacement_text.push_str(new_name);
+            replacement_text.push_str(": ");
+            TextRange::from_to(
+                reference.file_range.range.start(),
+                reference.file_range.range.start(),
+            )
+        }
+        ReferenceKind::StructFieldShorthandForLocal => {
+            replacement_text.push_str(": ");
+            replacement_text.push_str(new_name);
+            TextRange::from_to(reference.file_range.range.end(), reference.file_range.range.end())
+        }
+        _ => {
+            replacement_text.push_str(new_name);
+            reference.file_range.range
+        }
+    };
+    SourceFileEdit { file_id, edit: TextEdit::replace(range, replacement_text) }
 }
 
 fn rename_mod(
@@ -99,13 +117,10 @@ fn rename_mod(
     source_file_edits.push(edit);
 
     if let Some(RangeInfo { range: _, info: refs }) = find_all_refs(sema.db, position, None) {
-        let ref_edits = refs.references.into_iter().map(|reference| {
-            source_edit_from_file_id_range(
-                reference.file_range.file_id,
-                reference.file_range.range,
-                new_name,
-            )
-        });
+        let ref_edits = refs
+            .references
+            .into_iter()
+            .map(|reference| source_edit_from_reference(reference, new_name));
         source_file_edits.extend(ref_edits);
     }
 
@@ -121,13 +136,7 @@ fn rename_reference(
 
     let edit = refs
         .into_iter()
-        .map(|reference| {
-            source_edit_from_file_id_range(
-                reference.file_range.file_id,
-                reference.file_range.range,
-                new_name,
-            )
-        })
+        .map(|reference| source_edit_from_reference(reference, new_name))
         .collect::<Vec<_>>();
 
     if edit.is_empty() {
@@ -286,6 +295,163 @@ mod tests {
     }
 
     #[test]
+    fn test_rename_struct_field() {
+        test_rename(
+            r#"
+    struct Foo {
+        i<|>: i32,
+    }
+
+    impl Foo {
+        fn new(i: i32) -> Self {
+            Self { i: i }
+        }
+    }
+    "#,
+            "j",
+            r#"
+    struct Foo {
+        j: i32,
+    }
+
+    impl Foo {
+        fn new(i: i32) -> Self {
+            Self { j: i }
+        }
+    }
+    "#,
+        );
+    }
+
+    #[test]
+    fn test_rename_struct_field_for_shorthand() {
+        test_rename(
+            r#"
+    struct Foo {
+        i<|>: i32,
+    }
+
+    impl Foo {
+        fn new(i: i32) -> Self {
+            Self { i }
+        }
+    }
+    "#,
+            "j",
+            r#"
+    struct Foo {
+        j: i32,
+    }
+
+    impl Foo {
+        fn new(i: i32) -> Self {
+            Self { j: i }
+        }
+    }
+    "#,
+        );
+    }
+
+    #[test]
+    fn test_rename_local_for_field_shorthand() {
+        test_rename(
+            r#"
+    struct Foo {
+        i: i32,
+    }
+
+    impl Foo {
+        fn new(i<|>: i32) -> Self {
+            Self { i }
+        }
+    }
+    "#,
+            "j",
+            r#"
+    struct Foo {
+        i: i32,
+    }
+
+    impl Foo {
+        fn new(j: i32) -> Self {
+            Self { i: j }
+        }
+    }
+    "#,
+        );
+    }
+
+    #[test]
+    fn test_field_shorthand_correct_struct() {
+        test_rename(
+            r#"
+    struct Foo {
+        i<|>: i32,
+    }
+
+    struct Bar {
+        i: i32,
+    }
+
+    impl Bar {
+        fn new(i: i32) -> Self {
+            Self { i }
+        }
+    }
+    "#,
+            "j",
+            r#"
+    struct Foo {
+        j: i32,
+    }
+
+    struct Bar {
+        i: i32,
+    }
+
+    impl Bar {
+        fn new(i: i32) -> Self {
+            Self { i }
+        }
+    }
+    "#,
+        );
+    }
+
+    #[test]
+    fn test_shadow_local_for_struct_shorthand() {
+        test_rename(
+            r#"
+    struct Foo {
+        i: i32,
+    }
+
+    fn baz(i<|>: i32) -> Self {
+         let x = Foo { i };
+         {
+             let i = 0;
+             Foo { i }
+         }
+     }
+    "#,
+            "j",
+            r#"
+    struct Foo {
+        i: i32,
+    }
+
+    fn baz(j: i32) -> Self {
+         let x = Foo { i: j };
+         {
+             let i = 0;
+             Foo { i }
+         }
+     }
+    "#,
+        );
+    }
+
+    #[test]
     fn test_rename_mod() {
         let (analysis, position) = analysis_and_position(
             "
diff --git a/crates/ra_ide/src/typing.rs b/crates/ra_ide/src/typing.rs
index 7f1b9150f..53c65f8bc 100644
--- a/crates/ra_ide/src/typing.rs
+++ b/crates/ra_ide/src/typing.rs
@@ -13,77 +13,21 @@
 //! Language server executes such typing assists synchronously. That is, they
 //! block user's typing and should be pretty fast for this reason!
 
+mod on_enter;
+
 use ra_db::{FilePosition, SourceDatabase};
 use ra_fmt::leading_indent;
 use ra_ide_db::RootDatabase;
 use ra_syntax::{
     algo::find_node_at_offset,
     ast::{self, AstToken},
-    AstNode, SmolStr, SourceFile,
-    SyntaxKind::*,
-    SyntaxToken, TextRange, TextUnit, TokenAtOffset,
+    AstNode, SourceFile, TextRange, TextUnit,
 };
 use ra_text_edit::TextEdit;
 
-use crate::{source_change::SingleFileChange, SourceChange, SourceFileEdit};
-
-pub(crate) fn on_enter(db: &RootDatabase, position: FilePosition) -> Option<SourceChange> {
-    let parse = db.parse(position.file_id);
-    let file = parse.tree();
-    let comment = file
-        .syntax()
-        .token_at_offset(position.offset)
-        .left_biased()
-        .and_then(ast::Comment::cast)?;
-
-    if comment.kind().shape.is_block() {
-        return None;
-    }
-
-    let prefix = comment.prefix();
-    let comment_range = comment.syntax().text_range();
-    if position.offset < comment_range.start() + TextUnit::of_str(prefix) {
-        return None;
-    }
-
-    // Continuing non-doc line comments (like this one :) ) is annoying
-    if prefix == "//" && comment_range.end() == position.offset {
-        return None;
-    }
-
-    let indent = node_indent(&file, comment.syntax())?;
-    let inserted = format!("\n{}{} ", indent, prefix);
-    let cursor_position = position.offset + TextUnit::of_str(&inserted);
-    let edit = TextEdit::insert(position.offset, inserted);
+use crate::{source_change::SingleFileChange, SourceChange};
 
-    Some(
-        SourceChange::source_file_edit(
-            "on enter",
-            SourceFileEdit { edit, file_id: position.file_id },
-        )
-        .with_cursor(FilePosition { offset: cursor_position, file_id: position.file_id }),
-    )
-}
-
-fn node_indent(file: &SourceFile, token: &SyntaxToken) -> Option<SmolStr> {
-    let ws = match file.syntax().token_at_offset(token.text_range().start()) {
-        TokenAtOffset::Between(l, r) => {
-            assert!(r == *token);
-            l
-        }
-        TokenAtOffset::Single(n) => {
-            assert!(n == *token);
-            return Some("".into());
-        }
-        TokenAtOffset::None => unreachable!(),
-    };
-    if ws.kind() != WHITESPACE {
-        return None;
-    }
-    let text = ws.text();
-    let pos = text.rfind('\n').map(|it| it + 1).unwrap_or(0);
-    Some(text[pos..].into())
-}
+pub(crate) use on_enter::on_enter;
 
 pub(crate) const TRIGGER_CHARS: &str = ".=>";
 
@@ -196,102 +140,10 @@ fn on_arrow_typed(file: &SourceFile, offset: TextUnit) -> Option<SingleFileChang
 
 #[cfg(test)]
 mod tests {
-    use test_utils::{add_cursor, assert_eq_text, extract_offset};
-
-    use crate::mock_analysis::single_file;
+    use test_utils::{assert_eq_text, extract_offset};
 
     use super::*;
 
-    #[test]
-    fn test_on_enter() {
-        fn apply_on_enter(before: &str) -> Option<String> {
-            let (offset, before) = extract_offset(before);
-            let (analysis, file_id) = single_file(&before);
-            let result = analysis.on_enter(FilePosition { offset, file_id }).unwrap()?;
-
-            assert_eq!(result.source_file_edits.len(), 1);
-            let actual = result.source_file_edits[0].edit.apply(&before);
-            let actual = add_cursor(&actual, result.cursor_position.unwrap().offset);
-            Some(actual)
-        }
-
-        fn do_check(before: &str, after: &str) {
-            let actual = apply_on_enter(before).unwrap();
-            assert_eq_text!(after, &actual);
-        }
-
-        fn do_check_noop(text: &str) {
-            assert!(apply_on_enter(text).is_none())
-        }
-
-        do_check(
-            r"
-/// Some docs<|>
-fn foo() {
-}
-",
-            r"
-/// Some docs
-/// <|>
-fn foo() {
-}
-",
-        );
-        do_check(
-            r"
-impl S {
-    /// Some<|> docs.
-    fn foo() {}
-}
-",
-            r"
-impl S {
-    /// Some
-    /// <|> docs.
-    fn foo() {}
-}
-",
-        );
-        do_check(
-            r"
-fn main() {
-    // Fix<|> me
-    let x = 1 + 1;
-}
-",
-            r"
-fn main() {
-    // Fix
-    // <|> me
-    let x = 1 + 1;
-}
-",
-        );
-        do_check(
-            r"
-///<|> Some docs
-fn foo() {
-}
-",
-            r"
-///
-/// <|> Some docs
-fn foo() {
-}
-",
-        );
-        do_check_noop(
-            r"
-fn main() {
-    // Fix me<|>
-    let x = 1 + 1;
-}
-",
-        );
-
-        do_check_noop(r"<|>//! docz");
-    }
-
     fn do_type_char(char_typed: char, before: &str) -> Option<(String, SingleFileChange)> {
         let (offset, before) = extract_offset(before);
         let edit = TextEdit::insert(offset, char_typed.to_string());
diff --git a/crates/ra_ide/src/typing/on_enter.rs b/crates/ra_ide/src/typing/on_enter.rs
new file mode 100644
index 000000000..6bcf2d72b
--- /dev/null
+++ b/crates/ra_ide/src/typing/on_enter.rs
@@ -0,0 +1,216 @@
+//! Handles the `Enter` key press. At the momently, this only continues
+//! comments, but should handle indent some time in the future as well.
+
+use ra_db::{FilePosition, SourceDatabase};
+use ra_ide_db::RootDatabase;
+use ra_syntax::{
+    ast::{self, AstToken},
+    AstNode, SmolStr, SourceFile,
+    SyntaxKind::*,
+    SyntaxToken, TextUnit, TokenAtOffset,
+};
+use ra_text_edit::TextEdit;
+
+use crate::{SourceChange, SourceFileEdit};
+
+pub(crate) fn on_enter(db: &RootDatabase, position: FilePosition) -> Option<SourceChange> {
+    let parse = db.parse(position.file_id);
+    let file = parse.tree();
+    let comment = file
+        .syntax()
+        .token_at_offset(position.offset)
+        .left_biased()
+        .and_then(ast::Comment::cast)?;
+
+    if comment.kind().shape.is_block() {
+        return None;
+    }
+
+    let prefix = comment.prefix();
+    let comment_range = comment.syntax().text_range();
+    if position.offset < comment_range.start() + TextUnit::of_str(prefix) {
+        return None;
+    }
+
+    // Continuing single-line non-doc comments (like this one :) ) is annoying
+    if prefix == "//" && comment_range.end() == position.offset && !followed_by_comment(&comment) {
+        return None;
+    }
+
+    let indent = node_indent(&file, comment.syntax())?;
+    let inserted = format!("\n{}{} ", indent, prefix);
+    let cursor_position = position.offset + TextUnit::of_str(&inserted);
+    let edit = TextEdit::insert(position.offset, inserted);
+
+    Some(
+        SourceChange::source_file_edit(
+            "on enter",
+            SourceFileEdit { edit, file_id: position.file_id },
+        )
+        .with_cursor(FilePosition { offset: cursor_position, file_id: position.file_id }),
+    )
+}
+
+fn followed_by_comment(comment: &ast::Comment) -> bool {
+    let ws = match comment.syntax().next_token().and_then(ast::Whitespace::cast) {
+        Some(it) => it,
+        None => return false,
+    };
+    if ws.spans_multiple_lines() {
+        return false;
+    }
+    ws.syntax().next_token().and_then(ast::Comment::cast).is_some()
+}
+
+fn node_indent(file: &SourceFile, token: &SyntaxToken) -> Option<SmolStr> {
+    let ws = match file.syntax().token_at_offset(token.text_range().start()) {
+        TokenAtOffset::Between(l, r) => {
+            assert!(r == *token);
+            l
+        }
+        TokenAtOffset::Single(n) => {
+            assert!(n == *token);
+            return Some("".into());
+        }
+        TokenAtOffset::None => unreachable!(),
+    };
+    if ws.kind() != WHITESPACE {
+        return None;
+    }
+    let text = ws.text();
+    let pos = text.rfind('\n').map(|it| it + 1).unwrap_or(0);
+    Some(text[pos..].into())
+}
+
+#[cfg(test)]
+mod tests {
+    use test_utils::{add_cursor, assert_eq_text, extract_offset};
+
+    use crate::mock_analysis::single_file;
+
+    use super::*;
+
+    fn apply_on_enter(before: &str) -> Option<String> {
+        let (offset, before) = extract_offset(before);
+        let (analysis, file_id) = single_file(&before);
+        let result = analysis.on_enter(FilePosition { offset, file_id }).unwrap()?;
+
+        assert_eq!(result.source_file_edits.len(), 1);
+        let actual = result.source_file_edits[0].edit.apply(&before);
+        let actual = add_cursor(&actual, result.cursor_position.unwrap().offset);
+        Some(actual)
+    }
+
+    fn do_check(ra_fixture_before: &str, ra_fixture_after: &str) {
+        let actual = apply_on_enter(ra_fixture_before).unwrap();
+        assert_eq_text!(ra_fixture_after, &actual);
+    }
+
+    fn do_check_noop(ra_fixture_text: &str) {
+        assert!(apply_on_enter(ra_fixture_text).is_none())
+    }
+
+    #[test]
+    fn continues_doc_comment() {
+        do_check(
+            r"
+/// Some docs<|>
+fn foo() {
+}
+",
+            r"
+/// Some docs
+/// <|>
+fn foo() {
+}
+",
+        );
+
+        do_check(
+            r"
+impl S {
+    /// Some<|> docs.
+    fn foo() {}
+}
+",
+            r"
+impl S {
+    /// Some
+    /// <|> docs.
+    fn foo() {}
+}
+",
+        );
+
+        do_check(
+            r"
+///<|> Some docs
+fn foo() {
+}
+",
+            r"
+///
+/// <|> Some docs
+fn foo() {
+}
+",
+        );
+    }
+
+    #[test]
+    fn does_not_continue_before_doc_comment() {
+        do_check_noop(r"<|>//! docz");
+    }
+
+    #[test]
+    fn continues_code_comment_in_the_middle_of_line() {
+        do_check(
+            r"
+fn main() {
+    // Fix<|> me
+    let x = 1 + 1;
+}
+",
+            r"
+fn main() {
+    // Fix
+    // <|> me
+    let x = 1 + 1;
+}
+",
+        );
+    }
+
+    #[test]
+    fn continues_code_comment_in_the_middle_several_lines() {
+        do_check(
+            r"
+fn main() {
+    // Fix<|>
+    // me
+    let x = 1 + 1;
+}
+",
+            r"
+fn main() {
+    // Fix
+    // <|>
+    // me
+    let x = 1 + 1;
+}
+",
+        );
+    }
+
+    #[test]
+    fn does_not_continue_end_of_code_comment() {
+        do_check_noop(
+            r"
+fn main() {
+    // Fix me<|>
+    let x = 1 + 1;
+}
+",
+        );
+    }
+}
diff --git a/crates/ra_ide_db/src/lib.rs b/crates/ra_ide_db/src/lib.rs
index 6bcccc848..fc1b19def 100644
--- a/crates/ra_ide_db/src/lib.rs
+++ b/crates/ra_ide_db/src/lib.rs
@@ -55,6 +55,13 @@ impl FileLoader for RootDatabase {
     fn relevant_crates(&self, file_id: FileId) -> Arc<Vec<CrateId>> {
         FileLoaderDelegate(self).relevant_crates(file_id)
     }
+    fn resolve_extern_path(
+        &self,
+        extern_id: ra_db::ExternSourceId,
+        relative_path: &RelativePath,
+    ) -> Option<FileId> {
+        FileLoaderDelegate(self).resolve_extern_path(extern_id, relative_path)
+    }
 }
 
 impl salsa::Database for RootDatabase {
diff --git a/crates/ra_ide_db/src/search.rs b/crates/ra_ide_db/src/search.rs
index 6f198df04..cf78d3e41 100644
--- a/crates/ra_ide_db/src/search.rs
+++ b/crates/ra_ide_db/src/search.rs
@@ -17,7 +17,7 @@ use rustc_hash::FxHashMap;
 use test_utils::tested_by;
 
 use crate::{
-    defs::{classify_name_ref, Definition},
+    defs::{classify_name_ref, Definition, NameRefClass},
     RootDatabase,
 };
 
@@ -30,6 +30,8 @@ pub struct Reference {
 
 #[derive(Debug, Clone, PartialEq)]
 pub enum ReferenceKind {
+    StructFieldShorthandForField,
+    StructFieldShorthandForLocal,
     StructLiteral,
     Other,
 }
@@ -237,9 +239,8 @@ impl Definition {
                 // FIXME: reuse sb
                 // See https://github.com/rust-lang/rust/pull/68198#issuecomment-574269098
 
-                if let Some(d) = classify_name_ref(&sema, &name_ref) {
-                    let d = d.definition();
-                    if &d == self {
+                match classify_name_ref(&sema, &name_ref) {
+                    Some(NameRefClass::Definition(def)) if &def == self => {
                         let kind = if is_record_lit_name_ref(&name_ref)
                             || is_call_expr_name_ref(&name_ref)
                         {
@@ -252,9 +253,26 @@ impl Definition {
                         refs.push(Reference {
                             file_range,
                             kind,
-                            access: reference_access(&d, &name_ref),
+                            access: reference_access(&def, &name_ref),
                         });
                     }
+                    Some(NameRefClass::FieldShorthand { local, field }) => {
+                        match self {
+                            Definition::StructField(_) if &field == self => refs.push(Reference {
+                                file_range: sema.original_range(name_ref.syntax()),
+                                kind: ReferenceKind::StructFieldShorthandForField,
+                                access: reference_access(&field, &name_ref),
+                            }),
+                            Definition::Local(l) if &local == l => refs.push(Reference {
+                                file_range: sema.original_range(name_ref.syntax()),
+                                kind: ReferenceKind::StructFieldShorthandForLocal,
+                                access: reference_access(&Definition::Local(local), &name_ref),
+                            }),
+
+                            _ => {} // not a usage
+                        };
+                    }
+                    _ => {} // not a usage
                 }
             }
         }
diff --git a/crates/ra_parser/src/grammar/expressions.rs b/crates/ra_parser/src/grammar/expressions.rs
index 4163a2cf5..0c170ac5e 100644
--- a/crates/ra_parser/src/grammar/expressions.rs
+++ b/crates/ra_parser/src/grammar/expressions.rs
@@ -278,7 +278,7 @@ fn current_op(p: &Parser) -> (u8, SyntaxKind) {
 }
 
 // Parses expression with binding power of at least bp.
-fn expr_bp(p: &mut Parser, r: Restrictions, bp: u8) -> (Option<CompletedMarker>, BlockLike) {
+fn expr_bp(p: &mut Parser, mut r: Restrictions, bp: u8) -> (Option<CompletedMarker>, BlockLike) {
     let mut lhs = match lhs(p, r) {
         Some((lhs, blocklike)) => {
             // test stmt_bin_expr_ambiguity
@@ -311,6 +311,12 @@ fn expr_bp(p: &mut Parser, r: Restrictions, bp: u8) -> (Option<CompletedMarker>,
         let m = lhs.precede(p);
         p.bump(op);
 
+        // test binop_resets_statementness
+        // fn foo() {
+        //     v = {1}&2;
+        // }
+        r = Restrictions { prefer_stmt: false, ..r };
+
         if is_range {
             // test postfix_range
             // fn foo() {
@@ -327,7 +333,7 @@ fn expr_bp(p: &mut Parser, r: Restrictions, bp: u8) -> (Option<CompletedMarker>,
             }
         }
 
-        expr_bp(p, r, op_bp + 1);
+        expr_bp(p, Restrictions { prefer_stmt: false, ..r }, op_bp + 1);
         lhs = m.complete(p, if is_range { RANGE_EXPR } else { BIN_EXPR });
     }
     (Some(lhs), BlockLike::NotBlock)
diff --git a/crates/ra_project_model/src/lib.rs b/crates/ra_project_model/src/lib.rs
index 37845ca56..a6274709d 100644
--- a/crates/ra_project_model/src/lib.rs
+++ b/crates/ra_project_model/src/lib.rs
@@ -14,7 +14,7 @@ use std::{
 
 use anyhow::{bail, Context, Result};
 use ra_cfg::CfgOptions;
-use ra_db::{CrateGraph, CrateName, Edition, Env, FileId};
+use ra_db::{CrateGraph, CrateName, Edition, Env, ExternSource, ExternSourceId, FileId};
 use rustc_hash::FxHashMap;
 use serde_json::from_reader;
 
@@ -162,6 +162,7 @@ impl ProjectWorkspace {
     pub fn to_crate_graph(
         &self,
         default_cfg_options: &CfgOptions,
+        outdirs: &FxHashMap<String, (ExternSourceId, String)>,
         load: &mut dyn FnMut(&Path) -> Option<FileId>,
     ) -> CrateGraph {
         let mut crate_graph = CrateGraph::default();
@@ -185,6 +186,8 @@ impl ProjectWorkspace {
                             }
                             opts
                         };
+
+                        // FIXME: No crate name in json definition such that we cannot add OUT_DIR to env
                         crates.insert(
                             crate_id,
                             crate_graph.add_crate_root(
@@ -194,6 +197,7 @@ impl ProjectWorkspace {
                                 None,
                                 cfg_options,
                                 Env::default(),
+                                Default::default(),
                             ),
                         );
                     }
@@ -231,12 +235,20 @@ impl ProjectWorkspace {
                             opts
                         };
 
+                        let mut env = Env::default();
+                        let mut extern_source = ExternSource::default();
+                        if let Some((id, path)) = outdirs.get(krate.name(&sysroot)) {
+                            env.set("OUT_DIR", path.clone());
+                            extern_source.set_extern_path(&path, *id);
+                        }
+
                         let crate_id = crate_graph.add_crate_root(
                             file_id,
                             Edition::Edition2018,
                             Some(krate.name(&sysroot).to_string()),
                             cfg_options,
-                            Env::default(),
+                            env,
+                            extern_source,
                         );
                         sysroot_crates.insert(krate, crate_id);
                     }
@@ -275,12 +287,19 @@ impl ProjectWorkspace {
                                 opts.insert_features(pkg.features(&cargo).iter().map(Into::into));
                                 opts
                             };
+                            let mut env = Env::default();
+                            let mut extern_source = ExternSource::default();
+                            if let Some((id, path)) = outdirs.get(pkg.name(&cargo)) {
+                                env.set("OUT_DIR", path.clone());
+                                extern_source.set_extern_path(&path, *id);
+                            }
                             let crate_id = crate_graph.add_crate_root(
                                 file_id,
                                 edition,
                                 Some(pkg.name(&cargo).to_string()),
                                 cfg_options,
-                                Env::default(),
+                                env,
+                                extern_source,
                             );
                             if tgt.kind(&cargo) == TargetKind::Lib {
                                 lib_tgt = Some(crate_id);
diff --git a/crates/ra_syntax/src/ast.rs b/crates/ra_syntax/src/ast.rs
index 4a70c712f..26fafb469 100644
--- a/crates/ra_syntax/src/ast.rs
+++ b/crates/ra_syntax/src/ast.rs
@@ -30,7 +30,7 @@ pub use self::{
 /// conversion itself has zero runtime cost: ast and syntax nodes have exactly
 /// the same representation: a pointer to the tree root and a pointer to the
 /// node itself.
-pub trait AstNode {
+pub trait AstNode: std::fmt::Display {
     fn can_cast(kind: SyntaxKind) -> bool
     where
         Self: Sized;
diff --git a/crates/ra_syntax/src/ast/generated.rs b/crates/ra_syntax/src/ast/generated.rs
index 150893e39..002f453cd 100644
--- a/crates/ra_syntax/src/ast/generated.rs
+++ b/crates/ra_syntax/src/ast/generated.rs
@@ -9,6 +9,11 @@ use crate::{
 pub struct SourceFile {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for SourceFile {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for SourceFile {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -38,6 +43,11 @@ impl SourceFile {
 pub struct FnDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for FnDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for FnDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -76,6 +86,11 @@ impl FnDef {
 pub struct RetType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RetType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RetType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -103,6 +118,11 @@ impl RetType {
 pub struct StructDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for StructDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for StructDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -131,6 +151,11 @@ impl StructDef {}
 pub struct UnionDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for UnionDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for UnionDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -163,6 +188,11 @@ impl UnionDef {
 pub struct RecordFieldDefList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RecordFieldDefList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RecordFieldDefList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -190,6 +220,11 @@ impl RecordFieldDefList {
 pub struct RecordFieldDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RecordFieldDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RecordFieldDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -218,6 +253,11 @@ impl RecordFieldDef {}
 pub struct TupleFieldDefList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TupleFieldDefList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TupleFieldDefList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -245,6 +285,11 @@ impl TupleFieldDefList {
 pub struct TupleFieldDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TupleFieldDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TupleFieldDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -274,6 +319,11 @@ impl TupleFieldDef {
 pub struct EnumDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for EnumDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for EnumDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -306,6 +356,11 @@ impl EnumDef {
 pub struct EnumVariantList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for EnumVariantList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for EnumVariantList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -333,6 +388,11 @@ impl EnumVariantList {
 pub struct EnumVariant {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for EnumVariant {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for EnumVariant {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -363,6 +423,11 @@ impl EnumVariant {
 pub struct TraitDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TraitDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TraitDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -396,6 +461,11 @@ impl TraitDef {
 pub struct Module {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Module {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Module {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -427,6 +497,11 @@ impl Module {
 pub struct ItemList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ItemList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ItemList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -456,6 +531,11 @@ impl ItemList {
 pub struct ConstDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ConstDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ConstDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -489,6 +569,11 @@ impl ConstDef {
 pub struct StaticDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for StaticDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for StaticDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -522,6 +607,11 @@ impl StaticDef {
 pub struct TypeAliasDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TypeAliasDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TypeAliasDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -555,6 +645,11 @@ impl TypeAliasDef {
 pub struct ImplDef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ImplDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ImplDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -584,6 +679,11 @@ impl ImplDef {
 pub struct ParenType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ParenType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ParenType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -611,6 +711,11 @@ impl ParenType {
 pub struct TupleType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TupleType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TupleType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -638,6 +743,11 @@ impl TupleType {
 pub struct NeverType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for NeverType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for NeverType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -661,6 +771,11 @@ impl NeverType {}
 pub struct PathType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for PathType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for PathType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -688,6 +803,11 @@ impl PathType {
 pub struct PointerType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for PointerType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for PointerType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -715,6 +835,11 @@ impl PointerType {
 pub struct ArrayType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ArrayType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ArrayType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -745,6 +870,11 @@ impl ArrayType {
 pub struct SliceType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for SliceType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for SliceType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -772,6 +902,11 @@ impl SliceType {
 pub struct ReferenceType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ReferenceType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ReferenceType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -799,6 +934,11 @@ impl ReferenceType {
 pub struct PlaceholderType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for PlaceholderType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for PlaceholderType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -822,6 +962,11 @@ impl PlaceholderType {}
 pub struct FnPointerType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for FnPointerType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for FnPointerType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -852,6 +997,11 @@ impl FnPointerType {
 pub struct ForType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ForType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ForType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -879,6 +1029,11 @@ impl ForType {
 pub struct ImplTraitType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ImplTraitType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ImplTraitType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -903,6 +1058,11 @@ impl ImplTraitType {}
 pub struct DynTraitType {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for DynTraitType {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for DynTraitType {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -927,6 +1087,11 @@ impl DynTraitType {}
 pub struct TupleExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TupleExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TupleExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -954,6 +1119,11 @@ impl TupleExpr {
 pub struct ArrayExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ArrayExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ArrayExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -981,6 +1151,11 @@ impl ArrayExpr {
 pub struct ParenExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ParenExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ParenExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1008,6 +1183,11 @@ impl ParenExpr {
 pub struct PathExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for PathExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for PathExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1035,6 +1215,11 @@ impl PathExpr {
 pub struct LambdaExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for LambdaExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for LambdaExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1068,6 +1253,11 @@ impl LambdaExpr {
 pub struct IfExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for IfExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for IfExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1095,6 +1285,11 @@ impl IfExpr {
 pub struct LoopExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for LoopExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for LoopExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1119,6 +1314,11 @@ impl LoopExpr {}
 pub struct TryBlockExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TryBlockExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TryBlockExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1146,6 +1346,11 @@ impl TryBlockExpr {
 pub struct ForExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ForExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ForExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1177,6 +1382,11 @@ impl ForExpr {
 pub struct WhileExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for WhileExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for WhileExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1205,6 +1415,11 @@ impl WhileExpr {
 pub struct ContinueExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ContinueExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ContinueExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1228,6 +1443,11 @@ impl ContinueExpr {}
 pub struct BreakExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for BreakExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for BreakExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1255,6 +1475,11 @@ impl BreakExpr {
 pub struct Label {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Label {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Label {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1278,6 +1503,11 @@ impl Label {}
 pub struct BlockExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for BlockExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for BlockExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1305,6 +1535,11 @@ impl BlockExpr {
 pub struct ReturnExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ReturnExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ReturnExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1332,6 +1567,11 @@ impl ReturnExpr {
 pub struct CallExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for CallExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for CallExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1360,6 +1600,11 @@ impl CallExpr {
 pub struct MethodCallExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for MethodCallExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for MethodCallExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1394,6 +1639,11 @@ impl MethodCallExpr {
 pub struct IndexExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for IndexExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for IndexExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1417,6 +1667,11 @@ impl IndexExpr {}
 pub struct FieldExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for FieldExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for FieldExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1447,6 +1702,11 @@ impl FieldExpr {
 pub struct AwaitExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for AwaitExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for AwaitExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1474,6 +1734,11 @@ impl AwaitExpr {
 pub struct TryExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TryExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TryExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1501,6 +1766,11 @@ impl TryExpr {
 pub struct CastExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for CastExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for CastExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1531,6 +1801,11 @@ impl CastExpr {
 pub struct RefExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RefExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RefExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1558,6 +1833,11 @@ impl RefExpr {
 pub struct PrefixExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for PrefixExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for PrefixExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1585,6 +1865,11 @@ impl PrefixExpr {
 pub struct BoxExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for BoxExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for BoxExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1612,6 +1897,11 @@ impl BoxExpr {
 pub struct RangeExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RangeExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RangeExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1635,6 +1925,11 @@ impl RangeExpr {}
 pub struct BinExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for BinExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for BinExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1658,6 +1953,11 @@ impl BinExpr {}
 pub struct Literal {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Literal {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Literal {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1681,6 +1981,11 @@ impl Literal {}
 pub struct MatchExpr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for MatchExpr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for MatchExpr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1711,6 +2016,11 @@ impl MatchExpr {
 pub struct MatchArmList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for MatchArmList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for MatchArmList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1739,6 +2049,11 @@ impl MatchArmList {
 pub struct MatchArm {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for MatchArm {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for MatchArm {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1773,6 +2088,11 @@ impl MatchArm {
 pub struct MatchGuard {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for MatchGuard {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for MatchGuard {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1800,6 +2120,11 @@ impl MatchGuard {
 pub struct RecordLit {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RecordLit {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RecordLit {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1830,6 +2155,11 @@ impl RecordLit {
 pub struct RecordFieldList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RecordFieldList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RecordFieldList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1860,6 +2190,11 @@ impl RecordFieldList {
 pub struct RecordField {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RecordField {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RecordField {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1890,6 +2225,11 @@ impl RecordField {
 pub struct OrPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for OrPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for OrPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1917,6 +2257,11 @@ impl OrPat {
 pub struct ParenPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ParenPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ParenPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1944,6 +2289,11 @@ impl ParenPat {
 pub struct RefPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RefPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RefPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1971,6 +2321,11 @@ impl RefPat {
 pub struct BoxPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for BoxPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for BoxPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -1998,6 +2353,11 @@ impl BoxPat {
 pub struct BindPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for BindPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for BindPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2026,6 +2386,11 @@ impl BindPat {
 pub struct PlaceholderPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for PlaceholderPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for PlaceholderPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2049,6 +2414,11 @@ impl PlaceholderPat {}
 pub struct DotDotPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for DotDotPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for DotDotPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2072,6 +2442,11 @@ impl DotDotPat {}
 pub struct PathPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for PathPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for PathPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2099,6 +2474,11 @@ impl PathPat {
 pub struct SlicePat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for SlicePat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for SlicePat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2126,6 +2506,11 @@ impl SlicePat {
 pub struct RangePat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RangePat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RangePat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2149,6 +2534,11 @@ impl RangePat {}
 pub struct LiteralPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for LiteralPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for LiteralPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2176,6 +2566,11 @@ impl LiteralPat {
 pub struct RecordPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RecordPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RecordPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2206,6 +2601,11 @@ impl RecordPat {
 pub struct RecordFieldPatList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RecordFieldPatList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RecordFieldPatList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2236,6 +2636,11 @@ impl RecordFieldPatList {
 pub struct RecordFieldPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for RecordFieldPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for RecordFieldPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2264,6 +2669,11 @@ impl RecordFieldPat {
 pub struct TupleStructPat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TupleStructPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TupleStructPat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2294,6 +2704,11 @@ impl TupleStructPat {
 pub struct TuplePat {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TuplePat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TuplePat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2321,6 +2736,11 @@ impl TuplePat {
 pub struct Visibility {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Visibility {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Visibility {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2344,6 +2764,11 @@ impl Visibility {}
 pub struct Name {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Name {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Name {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2367,6 +2792,11 @@ impl Name {}
 pub struct NameRef {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for NameRef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for NameRef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2390,6 +2820,11 @@ impl NameRef {}
 pub struct MacroCall {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for MacroCall {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for MacroCall {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2423,6 +2858,11 @@ impl MacroCall {
 pub struct Attr {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Attr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Attr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2453,6 +2893,11 @@ impl Attr {
 pub struct TokenTree {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TokenTree {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TokenTree {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2476,6 +2921,11 @@ impl TokenTree {}
 pub struct TypeParamList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TypeParamList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TypeParamList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2506,6 +2956,11 @@ impl TypeParamList {
 pub struct TypeParam {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TypeParam {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TypeParam {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2536,6 +2991,11 @@ impl TypeParam {
 pub struct ConstParam {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ConstParam {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ConstParam {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2566,6 +3026,11 @@ impl ConstParam {
 pub struct LifetimeParam {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for LifetimeParam {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for LifetimeParam {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2590,6 +3055,11 @@ impl LifetimeParam {}
 pub struct TypeBound {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TypeBound {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TypeBound {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2617,6 +3087,11 @@ impl TypeBound {
 pub struct TypeBoundList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TypeBoundList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TypeBoundList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2644,6 +3119,11 @@ impl TypeBoundList {
 pub struct WherePred {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for WherePred {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for WherePred {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2672,6 +3152,11 @@ impl WherePred {
 pub struct WhereClause {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for WhereClause {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for WhereClause {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2699,6 +3184,11 @@ impl WhereClause {
 pub struct ExprStmt {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ExprStmt {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ExprStmt {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2726,6 +3216,11 @@ impl ExprStmt {
 pub struct LetStmt {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for LetStmt {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for LetStmt {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2757,6 +3252,11 @@ impl LetStmt {
 pub struct Condition {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Condition {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Condition {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2787,6 +3287,11 @@ impl Condition {
 pub struct Block {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Block {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Block {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2819,6 +3324,11 @@ impl Block {
 pub struct ParamList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ParamList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ParamList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2849,6 +3359,11 @@ impl ParamList {
 pub struct SelfParam {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for SelfParam {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for SelfParam {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2874,6 +3389,11 @@ impl SelfParam {}
 pub struct Param {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Param {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Param {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2903,6 +3423,11 @@ impl Param {
 pub struct UseItem {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for UseItem {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for UseItem {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2932,6 +3457,11 @@ impl UseItem {
 pub struct UseTree {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for UseTree {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for UseTree {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2965,6 +3495,11 @@ impl UseTree {
 pub struct Alias {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Alias {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Alias {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -2989,6 +3524,11 @@ impl Alias {}
 pub struct UseTreeList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for UseTreeList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for UseTreeList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3016,6 +3556,11 @@ impl UseTreeList {
 pub struct ExternCrateItem {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ExternCrateItem {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ExternCrateItem {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3048,6 +3593,11 @@ impl ExternCrateItem {
 pub struct ArgList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ArgList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ArgList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3075,6 +3625,11 @@ impl ArgList {
 pub struct Path {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for Path {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Path {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3105,6 +3660,11 @@ impl Path {
 pub struct PathSegment {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for PathSegment {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for PathSegment {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3144,6 +3704,11 @@ impl PathSegment {
 pub struct TypeArgList {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TypeArgList {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TypeArgList {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3180,6 +3745,11 @@ impl TypeArgList {
 pub struct TypeArg {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for TypeArg {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TypeArg {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3207,6 +3777,11 @@ impl TypeArg {
 pub struct AssocTypeArg {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for AssocTypeArg {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for AssocTypeArg {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3237,6 +3812,11 @@ impl AssocTypeArg {
 pub struct LifetimeArg {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for LifetimeArg {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for LifetimeArg {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3260,6 +3840,11 @@ impl LifetimeArg {}
 pub struct ConstArg {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for ConstArg {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ConstArg {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3290,6 +3875,11 @@ impl ConstArg {
 pub struct MacroItems {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for MacroItems {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for MacroItems {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3315,6 +3905,11 @@ impl MacroItems {}
 pub struct MacroStmts {
     pub(crate) syntax: SyntaxNode,
 }
+impl std::fmt::Display for MacroStmts {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for MacroStmts {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3362,6 +3957,11 @@ impl From<UnionDef> for NominalDef {
         NominalDef::UnionDef(node)
     }
 }
+impl std::fmt::Display for NominalDef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for NominalDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3470,6 +4070,11 @@ impl From<DynTraitType> for TypeRef {
         TypeRef::DynTraitType(node)
     }
 }
+impl std::fmt::Display for TypeRef {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for TypeRef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3591,6 +4196,11 @@ impl From<Module> for ModuleItem {
         ModuleItem::Module(node)
     }
 }
+impl std::fmt::Display for ModuleItem {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ModuleItem {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3657,6 +4267,11 @@ impl From<ConstDef> for ImplItem {
         ImplItem::ConstDef(node)
     }
 }
+impl std::fmt::Display for ImplItem {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for ImplItem {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -3871,6 +4486,11 @@ impl From<BoxExpr> for Expr {
         Expr::BoxExpr(node)
     }
 }
+impl std::fmt::Display for Expr {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Expr {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -4043,6 +4663,11 @@ impl From<LiteralPat> for Pat {
         Pat::LiteralPat(node)
     }
 }
+impl std::fmt::Display for Pat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Pat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -4106,6 +4731,11 @@ impl From<TokenTree> for AttrInput {
         AttrInput::TokenTree(node)
     }
 }
+impl std::fmt::Display for AttrInput {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for AttrInput {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
@@ -4143,6 +4773,11 @@ impl From<LetStmt> for Stmt {
         Stmt::LetStmt(node)
     }
 }
+impl std::fmt::Display for Stmt {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl AstNode for Stmt {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
diff --git a/crates/ra_syntax/test_data/parser/inline/ok/0158_binop_resets_statementness.rs b/crates/ra_syntax/test_data/parser/inline/ok/0158_binop_resets_statementness.rs
new file mode 100644
index 000000000..05acc30f1
--- /dev/null
+++ b/crates/ra_syntax/test_data/parser/inline/ok/0158_binop_resets_statementness.rs
@@ -0,0 +1,3 @@
+fn foo() {
+    v = {1}&2;
+}
diff --git a/crates/ra_syntax/test_data/parser/inline/ok/0158_binop_resets_statementness.txt b/crates/ra_syntax/test_data/parser/inline/ok/0158_binop_resets_statementness.txt
new file mode 100644
index 000000000..d568a1d45
--- /dev/null
+++ b/crates/ra_syntax/test_data/parser/inline/ok/0158_binop_resets_statementness.txt
@@ -0,0 +1,38 @@
+SOURCE_FILE@[0; 28)
+  FN_DEF@[0; 27)
+    FN_KW@[0; 2) "fn"
+    WHITESPACE@[2; 3) " "
+    NAME@[3; 6)
+      IDENT@[3; 6) "foo"
+    PARAM_LIST@[6; 8)
+      L_PAREN@[6; 7) "("
+      R_PAREN@[7; 8) ")"
+    WHITESPACE@[8; 9) " "
+    BLOCK_EXPR@[9; 27)
+      BLOCK@[9; 27)
+        L_CURLY@[9; 10) "{"
+        WHITESPACE@[10; 15) "\n    "
+        EXPR_STMT@[15; 25)
+          BIN_EXPR@[15; 24)
+            PATH_EXPR@[15; 16)
+              PATH@[15; 16)
+                PATH_SEGMENT@[15; 16)
+                  NAME_REF@[15; 16)
+                    IDENT@[15; 16) "v"
+            WHITESPACE@[16; 17) " "
+            EQ@[17; 18) "="
+            WHITESPACE@[18; 19) " "
+            BIN_EXPR@[19; 24)
+              BLOCK_EXPR@[19; 22)
+                BLOCK@[19; 22)
+                  L_CURLY@[19; 20) "{"
+                  LITERAL@[20; 21)
+                    INT_NUMBER@[20; 21) "1"
+                  R_CURLY@[21; 22) "}"
+              AMP@[22; 23) "&"
+              LITERAL@[23; 24)
+                INT_NUMBER@[23; 24) "2"
+          SEMI@[24; 25) ";"
+        WHITESPACE@[25; 26) "\n"
+        R_CURLY@[26; 27) "}"
+  WHITESPACE@[27; 28) "\n"
diff --git a/crates/rust-analyzer/src/cli/load_cargo.rs b/crates/rust-analyzer/src/cli/load_cargo.rs
index 5df29a383..2ce69c9b3 100644
--- a/crates/rust-analyzer/src/cli/load_cargo.rs
+++ b/crates/rust-analyzer/src/cli/load_cargo.rs
@@ -52,7 +52,10 @@ pub(crate) fn load_cargo(
         opts
     };
 
-    let crate_graph = ws.to_crate_graph(&default_cfg_options, &mut |path: &Path| {
+    // FIXME: outdirs?
+    let outdirs = FxHashMap::default();
+
+    let crate_graph = ws.to_crate_graph(&default_cfg_options, &outdirs, &mut |path: &Path| {
         let vfs_file = vfs.load(path);
         log::debug!("vfs file {:?} -> {:?}", path, vfs_file);
         vfs_file.map(vfs_file_to_id)
diff --git a/crates/rust-analyzer/src/config.rs b/crates/rust-analyzer/src/config.rs
index 3a6cfbe7b..bd5904db0 100644
--- a/crates/rust-analyzer/src/config.rs
+++ b/crates/rust-analyzer/src/config.rs
@@ -47,6 +47,9 @@ pub struct ServerConfig {
     /// Fine grained feature flags to disable specific features.
     pub feature_flags: FxHashMap<String, bool>,
 
+    /// Fine grained controls for additional `OUT_DIR` env variables
+    pub additional_out_dirs: FxHashMap<String, String>,
+
     pub rustfmt_args: Vec<String>,
 
     /// Cargo feature configurations.
@@ -67,6 +70,7 @@ impl Default for ServerConfig {
             cargo_watch_all_targets: true,
             with_sysroot: true,
             feature_flags: FxHashMap::default(),
+            additional_out_dirs: FxHashMap::default(),
             cargo_features: Default::default(),
             rustfmt_args: Vec::new(),
         }
diff --git a/crates/rust-analyzer/src/main_loop.rs b/crates/rust-analyzer/src/main_loop.rs
index b6d1f28d8..495056da3 100644
--- a/crates/rust-analyzer/src/main_loop.rs
+++ b/crates/rust-analyzer/src/main_loop.rs
@@ -196,6 +196,7 @@ pub fn main_loop(
             Watch(!config.use_client_watching),
             options,
             feature_flags,
+            config.additional_out_dirs,
         )
     };
 
diff --git a/crates/rust-analyzer/src/world.rs b/crates/rust-analyzer/src/world.rs
index 004803b00..d358f6b47 100644
--- a/crates/rust-analyzer/src/world.rs
+++ b/crates/rust-analyzer/src/world.rs
@@ -27,6 +27,8 @@ use crate::{
     vfs_glob::{Glob, RustPackageFilterBuilder},
     LspError, Result,
 };
+use ra_db::ExternSourceId;
+use rustc_hash::{FxHashMap, FxHashSet};
 
 #[derive(Debug, Clone)]
 pub struct Options {
@@ -79,6 +81,7 @@ impl WorldState {
         watch: Watch,
         options: Options,
         feature_flags: FeatureFlags,
+        additional_out_dirs: FxHashMap<String, String>,
     ) -> WorldState {
         let mut change = AnalysisChange::new();
 
@@ -100,6 +103,19 @@ impl WorldState {
                 RootEntry::new(pkg_root.path().clone(), filter.into_vfs_filter())
             }));
         }
+
+        let extern_dirs: FxHashSet<_> =
+            additional_out_dirs.iter().map(|(_, path)| (PathBuf::from(path))).collect();
+        let mut extern_source_roots = FxHashMap::default();
+
+        roots.extend(additional_out_dirs.iter().map(|(_, path)| {
+            let mut filter = RustPackageFilterBuilder::default().set_member(false);
+            for glob in exclude_globs.iter() {
+                filter = filter.exclude(glob.clone());
+            }
+            RootEntry::new(PathBuf::from(&path), filter.into_vfs_filter())
+        }));
+
         let (task_sender, task_receiver) = unbounded();
         let task_sender = Box::new(move |t| task_sender.send(t).unwrap());
         let (mut vfs, vfs_roots) = Vfs::new(roots, task_sender, watch);
@@ -109,6 +125,11 @@ impl WorldState {
             let is_local = folder_roots.iter().any(|it| vfs_root_path.starts_with(it));
             change.add_root(SourceRootId(r.0), is_local);
             change.set_debug_root_path(SourceRootId(r.0), vfs_root_path.display().to_string());
+
+            // FIXME: add path2root in vfs to simpily this logic
+            if extern_dirs.contains(&vfs_root_path) {
+                extern_source_roots.insert(vfs_root_path, ExternSourceId(r.0));
+            }
         }
 
         // FIXME: Read default cfgs from config
@@ -126,11 +147,20 @@ impl WorldState {
             vfs_file.map(|f| FileId(f.0))
         };
 
-        workspaces.iter().map(|ws| ws.to_crate_graph(&default_cfg_options, &mut load)).for_each(
-            |graph| {
+        let mut outdirs = FxHashMap::default();
+        for (name, path) in additional_out_dirs {
+            let path = PathBuf::from(&path);
+            if let Some(id) = extern_source_roots.get(&path) {
+                outdirs.insert(name, (id.clone(), path.to_string_lossy().replace("\\", "/")));
+            }
+        }
+
+        workspaces
+            .iter()
+            .map(|ws| ws.to_crate_graph(&default_cfg_options, &outdirs, &mut load))
+            .for_each(|graph| {
                 crate_graph.extend(graph);
-            },
-        );
+            });
         change.set_crate_graph(crate_graph);
 
         // FIXME: Figure out the multi-workspace situation
diff --git a/editors/code/package.json b/editors/code/package.json
index 78f3539e9..3aaae357a 100644
--- a/editors/code/package.json
+++ b/editors/code/package.json
@@ -224,6 +224,11 @@
                     "default": true,
                     "description": "Whether to ask for permission before downloading any files from the Internet"
                 },
+                "rust-analyzer.additionalOutDirs": {
+                    "type": "object",
+                    "default": {},
+                    "markdownDescription": "Fine grained controls for OUT_DIR `env!(\"OUT_DIR\")` variable. e.g. `{\"foo\":\"/path/to/foo\"}`, "
+                },
                 "rust-analyzer.serverPath": {
                     "type": [
                         "null",
@@ -256,7 +261,7 @@
                 "rust-analyzer.cargo-watch.enable": {
                     "type": "boolean",
                     "default": true,
-                    "markdownDescription": "Run `cargo check` for diagnostics on save"
+                    "markdownDescription": "Run specified `cargo-watch` command for diagnostics on save"
                 },
                 "rust-analyzer.cargo-watch.arguments": {
                     "type": "array",
diff --git a/editors/code/src/client.ts b/editors/code/src/client.ts
index 3b8ea6f77..e9f261c24 100644
--- a/editors/code/src/client.ts
+++ b/editors/code/src/client.ts
@@ -37,6 +37,7 @@ export async function createClient(config: Config, serverPath: string): Promise<
             excludeGlobs: config.excludeGlobs,
             useClientWatching: config.useClientWatching,
             featureFlags: config.featureFlags,
+            additionalOutDirs: config.additionalOutDirs,
             withSysroot: config.withSysroot,
             cargoFeatures: config.cargoFeatures,
             rustfmtArgs: config.rustfmtArgs,
diff --git a/editors/code/src/config.ts b/editors/code/src/config.ts
index c3b3ecabf..6db073bec 100644
--- a/editors/code/src/config.ts
+++ b/editors/code/src/config.ts
@@ -166,6 +166,7 @@ export class Config {
     get excludeGlobs() { return this.cfg.get("excludeGlobs") as string[]; }
     get useClientWatching() { return this.cfg.get("useClientWatching") as boolean; }
     get featureFlags() { return this.cfg.get("featureFlags") as Record<string, boolean>; }
+    get additionalOutDirs() { return this.cfg.get("additionalOutDirs") as Record<string, string>; }
     get rustfmtArgs() { return this.cfg.get("rustfmtArgs") as string[]; }
 
     get cargoWatchOptions(): CargoWatchOptions {
diff --git a/xtask/src/codegen/gen_syntax.rs b/xtask/src/codegen/gen_syntax.rs
index db05dcebb..32afd47bc 100644
--- a/xtask/src/codegen/gen_syntax.rs
+++ b/xtask/src/codegen/gen_syntax.rs
@@ -68,6 +68,12 @@ fn generate_ast(grammar: AstSrc<'_>) -> Result<String> {
                 pub(crate) syntax: SyntaxNode,
             }
 
+            impl std::fmt::Display for #name {
+                fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+                    std::fmt::Display::fmt(self.syntax(), f)
+                }
+            }
+
             impl AstNode for #name {
                 fn can_cast(kind: SyntaxKind) -> bool {
                     match kind {
@@ -114,6 +120,12 @@ fn generate_ast(grammar: AstSrc<'_>) -> Result<String> {
             }
             )*
 
+            impl std::fmt::Display for #name {
+                fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+                    std::fmt::Display::fmt(self.syntax(), f)
+                }
+            }
+
             impl AstNode for #name {
                 fn can_cast(kind: SyntaxKind) -> bool {
                     match kind {