Merge #1305

1305: Try to resolve name refs during highlighting r=matklad a=lnicola

Preview:

![image](https://user-images.githubusercontent.com/308347/58253075-43464a80-7d70-11e9-84cc-e81990f2d3eb.png)

This is probably not the cleanest implementation, but it's not clear to me what parts of `reference_definition` we don't want to run at this point. Also, is the `SourceAnalyzer` cheap enough to construct for each `NameRef`? Not like there's any alternative at this point, though.

Co-authored-by: Laurențiu Nicola <[email protected]>

2 files changed, 168 insertions, 9 deletions

diff --git a/crates/ra_ide_api/src/snapshots/tests__highlighting.snap b/crates/ra_ide_api/src/snapshots/tests__highlighting.snap
index 72029e0ed..9d4c04db3 100644
--- a/crates/ra_ide_api/src/snapshots/tests__highlighting.snap
+++ b/crates/ra_ide_api/src/snapshots/tests__highlighting.snap
@@ -1,33 +1,145 @@
 ---
-created: "2019-03-23T16:20:31.394314144Z"
-creator: insta@0.7.1
+created: "2019-05-23T12:10:32.628883358Z"
+creator: insta@0.8.1
 source: crates/ra_ide_api/src/syntax_highlighting.rs
 expression: result
 ---
 Ok(
     [
         HighlightedRange {
-            range: [1; 11),
+            range: [1; 24),
+            tag: "attribute"
+        },
+        HighlightedRange {
+            range: [25; 31),
+            tag: "keyword"
+        },
+        HighlightedRange {
+            range: [32; 35),
+            tag: "function"
+        },
+        HighlightedRange {
+            range: [42; 45),
+            tag: "keyword"
+        },
+        HighlightedRange {
+            range: [46; 47),
+            tag: "function"
+        },
+        HighlightedRange {
+            range: [49; 52),
+            tag: "text"
+        },
+        HighlightedRange {
+            range: [58; 61),
+            tag: "keyword"
+        },
+        HighlightedRange {
+            range: [62; 63),
+            tag: "function"
+        },
+        HighlightedRange {
+            range: [65; 68),
+            tag: "text"
+        },
+        HighlightedRange {
+            range: [73; 75),
+            tag: "keyword"
+        },
+        HighlightedRange {
+            range: [76; 79),
+            tag: "function"
+        },
+        HighlightedRange {
+            range: [80; 81),
+            tag: "type"
+        },
+        HighlightedRange {
+            range: [80; 81),
+            tag: "function"
+        },
+        HighlightedRange {
+            range: [88; 89),
+            tag: "type"
+        },
+        HighlightedRange {
+            range: [96; 110),
+            tag: "macro"
+        },
+        HighlightedRange {
+            range: [117; 127),
             tag: "comment"
         },
         HighlightedRange {
-            range: [12; 14),
+            range: [128; 130),
             tag: "keyword"
         },
         HighlightedRange {
-            range: [15; 19),
+            range: [131; 135),
             tag: "function"
         },
         HighlightedRange {
-            range: [29; 37),
+            range: [145; 153),
             tag: "macro"
         },
         HighlightedRange {
-            range: [38; 50),
+            range: [154; 166),
             tag: "string"
         },
         HighlightedRange {
-            range: [52; 54),
+            range: [168; 170),
+            tag: "literal"
+        },
+        HighlightedRange {
+            range: [178; 181),
+            tag: "keyword"
+        },
+        HighlightedRange {
+            range: [182; 185),
+            tag: "keyword"
+        },
+        HighlightedRange {
+            range: [186; 189),
+            tag: "macro"
+        },
+        HighlightedRange {
+            range: [197; 200),
+            tag: "macro"
+        },
+        HighlightedRange {
+            range: [192; 195),
+            tag: "text"
+        },
+        HighlightedRange {
+            range: [208; 211),
+            tag: "macro"
+        },
+        HighlightedRange {
+            range: [212; 216),
+            tag: "macro"
+        },
+        HighlightedRange {
+            range: [226; 227),
+            tag: "literal"
+        },
+        HighlightedRange {
+            range: [232; 233),
+            tag: "literal"
+        },
+        HighlightedRange {
+            range: [242; 248),
+            tag: "keyword.unsafe"
+        },
+        HighlightedRange {
+            range: [251; 254),
+            tag: "text"
+        },
+        HighlightedRange {
+            range: [255; 262),
+            tag: "text"
+        },
+        HighlightedRange {
+            range: [263; 264),
             tag: "literal"
         }
     ]
diff --git a/crates/ra_ide_api/src/syntax_highlighting.rs b/crates/ra_ide_api/src/syntax_highlighting.rs
index 2158291dc..89f20260f 100644
--- a/crates/ra_ide_api/src/syntax_highlighting.rs
+++ b/crates/ra_ide_api/src/syntax_highlighting.rs
@@ -40,8 +40,41 @@ pub(crate) fn highlight(db: &RootDatabase, file_id: FileId) -> Vec<HighlightedRa
             COMMENT => "comment",
             STRING | RAW_STRING | RAW_BYTE_STRING | BYTE_STRING => "string",
             ATTR => "attribute",
-            NAME_REF => "text",
+            NAME_REF => {
+                if let Some(name_ref) = node.as_node().and_then(|n| ast::NameRef::cast(n)) {
+                    use crate::name_ref_kind::{classify_name_ref, NameRefKind::*};
+                    use hir::{ModuleDef, ImplItem};
+
+                    // FIXME: try to reuse the SourceAnalyzers
+                    let analyzer = hir::SourceAnalyzer::new(db, file_id, name_ref.syntax(), None);
+                    match classify_name_ref(db, &analyzer, name_ref) {
+                        Some(Method(_)) => "function",
+                        Some(Macro(_)) => "macro",
+                        Some(FieldAccess(_)) => "field",
+                        Some(AssocItem(ImplItem::Method(_))) => "function",
+                        Some(AssocItem(ImplItem::Const(_))) => "constant",
+                        Some(AssocItem(ImplItem::TypeAlias(_))) => "type",
+                        Some(Def(ModuleDef::Module(_))) => "module",
+                        Some(Def(ModuleDef::Function(_))) => "function",
+                        Some(Def(ModuleDef::Struct(_))) => "type",
+                        Some(Def(ModuleDef::Enum(_))) => "type",
+                        Some(Def(ModuleDef::EnumVariant(_))) => "constant",
+                        Some(Def(ModuleDef::Const(_))) => "constant",
+                        Some(Def(ModuleDef::Static(_))) => "constant",
+                        Some(Def(ModuleDef::Trait(_))) => "type",
+                        Some(Def(ModuleDef::TypeAlias(_))) => "type",
+                        Some(SelfType(_)) => "type",
+                        Some(Pat(_)) => "text",
+                        Some(SelfParam(_)) => "type",
+                        Some(GenericParam(_)) => "type",
+                        None => "text",
+                    }
+                } else {
+                    "text"
+                }
+            }
             NAME => "function",
+            TYPE_ALIAS_DEF | TYPE_ARG | TYPE_PARAM => "type",
             INT_NUMBER | FLOAT_NUMBER | CHAR | BYTE => "literal",
             LIFETIME => "parameter",
             T![unsafe] => "keyword.unsafe",
@@ -87,9 +120,23 @@ mod tests {
     fn test_highlighting() {
         let (analysis, file_id) = single_file(
             r#"
+#[derive(Clone, Debug)]
+struct Foo {
+    pub x: i32,
+    pub y: i32,
+}
+
+fn foo<T>() -> T {
+    unimplemented!();
+}
+
 // comment
 fn main() {}
     println!("Hello, {}!", 92);
+
+    let mut vec = Vec::new();
+    vec.push(Foo { x: 0, y: 1 });
+    unsafe { vec.set_len(0); }
 "#,
         );
         let result = analysis.highlight(file_id);