24 files changed, 420 insertions, 157 deletions

diff --git a/crates/hir_ty/src/diagnostics/expr.rs b/crates/hir_ty/src/diagnostics/expr.rs
index 3efbce773..a2a4d61db 100644
--- a/crates/hir_ty/src/diagnostics/expr.rs
+++ b/crates/hir_ty/src/diagnostics/expr.rs
@@ -357,17 +357,20 @@ impl<'a, 'b> ExprValidator<'a, 'b> {
             infer: &infer,
             db,
             pattern_arena: &pattern_arena,
-            eprint_panic_context: &|| {
+            panic_context: &|| {
                 use syntax::AstNode;
-                if let Ok(scrutinee_sptr) = source_map.expr_syntax(match_expr) {
-                    let root = scrutinee_sptr.file_syntax(db.upcast());
-                    if let Some(match_ast) = scrutinee_sptr.value.to_node(&root).syntax().parent() {
-                        eprintln!(
-                            "Match checking is about to panic on this expression:\n{}",
-                            match_ast.to_string(),
-                        );
-                    }
-                }
+                let match_expr_text = source_map
+                    .expr_syntax(match_expr)
+                    .ok()
+                    .and_then(|scrutinee_sptr| {
+                        let root = scrutinee_sptr.file_syntax(db.upcast());
+                        scrutinee_sptr.value.to_node(&root).syntax().parent()
+                    })
+                    .map(|node| node.to_string());
+                format!(
+                    "expression:\n{}",
+                    match_expr_text.as_deref().unwrap_or("<synthesized expr>")
+                )
             },
         };
         let report = compute_match_usefulness(&cx, &m_arms);
diff --git a/crates/hir_ty/src/diagnostics/match_check.rs b/crates/hir_ty/src/diagnostics/match_check.rs
index a9a99f57a..c8e1b23de 100644
--- a/crates/hir_ty/src/diagnostics/match_check.rs
+++ b/crates/hir_ty/src/diagnostics/match_check.rs
@@ -100,10 +100,19 @@ impl<'a> PatCtxt<'a> {
     }
 
     pub(crate) fn lower_pattern(&mut self, pat: hir_def::expr::PatId) -> Pat {
-        // FIXME: implement pattern adjustments (implicit pattern dereference; "RFC 2005-match-ergonomics")
+        // XXX(iDawer): Collecting pattern adjustments feels imprecise to me.
+        // When lowering of & and box patterns are implemented this should be tested
+        // in a manner of `match_ergonomics_issue_9095` test.
+        // Pattern adjustment is part of RFC 2005-match-ergonomics.
         // More info https://github.com/rust-lang/rust/issues/42640#issuecomment-313535089
         let unadjusted_pat = self.lower_pattern_unadjusted(pat);
-        unadjusted_pat
+        self.infer.pat_adjustments.get(&pat).map(|it| &**it).unwrap_or_default().iter().rev().fold(
+            unadjusted_pat,
+            |subpattern, ref_ty| Pat {
+                ty: ref_ty.clone(),
+                kind: Box::new(PatKind::Deref { subpattern }),
+            },
+        )
     }
 
     fn lower_pattern_unadjusted(&mut self, pat: hir_def::expr::PatId) -> Pat {
@@ -1236,6 +1245,21 @@ fn main(f: Foo) {
         );
     }
 
+    #[test]
+    fn match_ergonomics_issue_9095() {
+        check_diagnostics(
+            r#"
+enum Foo<T> { A(T) }
+fn main() {
+    match &Foo::A(true) {
+        _ => {}
+        Foo::A(_) => {}
+    }
+}
+"#,
+        );
+    }
+
     mod false_negatives {
         //! The implementation of match checking here is a work in progress. As we roll this out, we
         //! prefer false negatives to false positives (ideally there would be no false positives). This
diff --git a/crates/hir_ty/src/diagnostics/match_check/usefulness.rs b/crates/hir_ty/src/diagnostics/match_check/usefulness.rs
index 83b094a89..bd76a606c 100644
--- a/crates/hir_ty/src/diagnostics/match_check/usefulness.rs
+++ b/crates/hir_ty/src/diagnostics/match_check/usefulness.rs
@@ -295,7 +295,7 @@ pub(crate) struct MatchCheckCtx<'a> {
     pub(crate) db: &'a dyn HirDatabase,
     /// Lowered patterns from arms plus generated by the check.
     pub(crate) pattern_arena: &'a RefCell<PatternArena>,
-    pub(crate) eprint_panic_context: &'a dyn Fn(),
+    pub(crate) panic_context: &'a dyn Fn() -> String,
 }
 
 impl<'a> MatchCheckCtx<'a> {
@@ -331,8 +331,7 @@ impl<'a> MatchCheckCtx<'a> {
 
     #[track_caller]
     pub(super) fn bug(&self, info: &str) -> ! {
-        (self.eprint_panic_context)();
-        panic!("bug: {}", info);
+        panic!("bug: {}\n{}", info, (self.panic_context)());
     }
 }
 
diff --git a/crates/hir_ty/src/infer.rs b/crates/hir_ty/src/infer.rs
index 7a4268819..0e9f777da 100644
--- a/crates/hir_ty/src/infer.rs
+++ b/crates/hir_ty/src/infer.rs
@@ -150,6 +150,8 @@ pub struct InferenceResult {
     type_mismatches: FxHashMap<ExprOrPatId, TypeMismatch>,
     /// Interned Unknown to return references to.
     standard_types: InternedStandardTypes,
+    /// Stores the types which were implicitly dereferenced in pattern binding modes.
+    pub pat_adjustments: FxHashMap<PatId, Vec<Ty>>,
 }
 
 impl InferenceResult {
diff --git a/crates/hir_ty/src/infer/pat.rs b/crates/hir_ty/src/infer/pat.rs
index 83e0a7a9e..25dff7e49 100644
--- a/crates/hir_ty/src/infer/pat.rs
+++ b/crates/hir_ty/src/infer/pat.rs
@@ -101,7 +101,9 @@ impl<'a> InferenceContext<'a> {
         let mut expected = self.resolve_ty_shallow(expected);
 
         if is_non_ref_pat(&body, pat) {
+            let mut pat_adjustments = Vec::new();
             while let Some((inner, _lifetime, mutability)) = expected.as_reference() {
+                pat_adjustments.push(expected.clone());
                 expected = self.resolve_ty_shallow(inner);
                 default_bm = match default_bm {
                     BindingMode::Move => BindingMode::Ref(mutability),
@@ -109,6 +111,11 @@ impl<'a> InferenceContext<'a> {
                     BindingMode::Ref(Mutability::Mut) => BindingMode::Ref(mutability),
                 }
             }
+
+            if !pat_adjustments.is_empty() {
+                pat_adjustments.shrink_to_fit();
+                self.result.pat_adjustments.insert(pat, pat_adjustments);
+            }
         } else if let Pat::Ref { .. } = &body[pat] {
             cov_mark::hit!(match_ergonomics_ref);
             // When you encounter a `&pat` pattern, reset to Move.
@@ -290,6 +297,10 @@ fn is_non_ref_pat(body: &hir_def::body::Body, pat: PatId) -> bool {
             Expr::Literal(Literal::String(..)) => false,
             _ => true,
         },
+        Pat::Bind { mode: BindingAnnotation::Mutable, subpat: Some(subpat), .. }
+        | Pat::Bind { mode: BindingAnnotation::Unannotated, subpat: Some(subpat), .. } => {
+            is_non_ref_pat(body, *subpat)
+        }
         Pat::Wild | Pat::Bind { .. } | Pat::Ref { .. } | Pat::Box { .. } | Pat::Missing => false,
     }
 }
diff --git a/crates/hir_ty/src/tests/patterns.rs b/crates/hir_ty/src/tests/patterns.rs
index cd08b5c7a..7d00cee9b 100644
--- a/crates/hir_ty/src/tests/patterns.rs
+++ b/crates/hir_ty/src/tests/patterns.rs
@@ -20,6 +20,8 @@ fn infer_pattern() {
                 let h = val;
             }
 
+            if let x @ true = &true {}
+
             let lambda = |a: u64, b, c: i32| { a + b; c };
 
             let ref ref_to_x = x;
@@ -30,7 +32,7 @@ fn infer_pattern() {
         "#,
         expect![[r#"
             8..9 'x': &i32
-            17..368 '{     ...o_x; }': ()
+            17..400 '{     ...o_x; }': ()
             27..28 'y': &i32
             31..32 'x': &i32
             42..44 '&z': &i32
@@ -59,24 +61,31 @@ fn infer_pattern() {
             176..204 '{     ...     }': ()
             190..191 'h': {unknown}
             194..197 'val': {unknown}
-            214..220 'lambda': |u64, u64, i32| -> i32
-            223..255 '|a: u6...b; c }': |u64, u64, i32| -> i32
-            224..225 'a': u64
-            232..233 'b': u64
-            235..236 'c': i32
-            243..255 '{ a + b; c }': i32
-            245..246 'a': u64
-            245..250 'a + b': u64
-            249..250 'b': u64
-            252..253 'c': i32
-            266..278 'ref ref_to_x': &&i32
-            281..282 'x': &i32
-            292..301 'mut mut_x': &i32
-            304..305 'x': &i32
-            315..335 'ref mu...f_to_x': &mut &i32
-            338..339 'x': &i32
-            349..350 'k': &mut &i32
-            353..365 'mut_ref_to_x': &mut &i32
+            210..236 'if let...rue {}': ()
+            217..225 'x @ true': &bool
+            221..225 'true': bool
+            221..225 'true': bool
+            228..233 '&true': &bool
+            229..233 'true': bool
+            234..236 '{}': ()
+            246..252 'lambda': |u64, u64, i32| -> i32
+            255..287 '|a: u6...b; c }': |u64, u64, i32| -> i32
+            256..257 'a': u64
+            264..265 'b': u64
+            267..268 'c': i32
+            275..287 '{ a + b; c }': i32
+            277..278 'a': u64
+            277..282 'a + b': u64
+            281..282 'b': u64
+            284..285 'c': i32
+            298..310 'ref ref_to_x': &&i32
+            313..314 'x': &i32
+            324..333 'mut mut_x': &i32
+            336..337 'x': &i32
+            347..367 'ref mu...f_to_x': &mut &i32
+            370..371 'x': &i32
+            381..382 'k': &mut &i32
+            385..397 'mut_ref_to_x': &mut &i32
         "#]],
     );
 }
diff --git a/crates/ide/src/expand_macro.rs b/crates/ide/src/expand_macro.rs
index eebae5ebe..e0d01fa96 100644
--- a/crates/ide/src/expand_macro.rs
+++ b/crates/ide/src/expand_macro.rs
@@ -28,8 +28,8 @@ pub struct ExpandedMacro {
 pub(crate) fn expand_macro(db: &RootDatabase, position: FilePosition) -> Option<ExpandedMacro> {
     let sema = Semantics::new(db);
     let file = sema.parse(position.file_id);
-    let name_ref = find_node_at_offset::<ast::NameRef>(file.syntax(), position.offset)?;
-    let mac = name_ref.syntax().ancestors().find_map(ast::MacroCall::cast)?;
+    let mac = find_node_at_offset::<ast::MacroCall>(file.syntax(), position.offset)?;
+    let name = mac.path()?.segment()?.name_ref()?;
 
     let expanded = expand_macro_recur(&sema, &mac)?;
 
@@ -37,7 +37,7 @@ pub(crate) fn expand_macro(db: &RootDatabase, position: FilePosition) -> Option<
     // macro expansion may lose all white space information
     // But we hope someday we can use ra_fmt for that
     let expansion = insert_whitespaces(expanded);
-    Some(ExpandedMacro { name: name_ref.text().to_string(), expansion })
+    Some(ExpandedMacro { name: name.to_string(), expansion })
 }
 
 fn expand_macro_recur(
diff --git a/crates/ide_assists/src/handlers/extract_struct_from_enum_variant.rs b/crates/ide_assists/src/handlers/extract_struct_from_enum_variant.rs
index 007aba23d..d3ff7b65c 100644
--- a/crates/ide_assists/src/handlers/extract_struct_from_enum_variant.rs
+++ b/crates/ide_assists/src/handlers/extract_struct_from_enum_variant.rs
@@ -11,14 +11,19 @@ use ide_db::{
     search::FileReference,
     RootDatabase,
 };
+use itertools::Itertools;
 use rustc_hash::FxHashSet;
 use syntax::{
-    algo::find_node_at_offset,
-    ast::{self, make, AstNode, NameOwner, VisibilityOwner},
-    ted, SyntaxNode, T,
+    ast::{
+        self, make, AstNode, AttrsOwner, GenericParamsOwner, NameOwner, TypeBoundsOwner,
+        VisibilityOwner,
+    },
+    match_ast,
+    ted::{self, Position},
+    SyntaxNode, T,
 };
 
-use crate::{AssistContext, AssistId, AssistKind, Assists};
+use crate::{assist_context::AssistBuilder, AssistContext, AssistId, AssistKind, Assists};
 
 // Assist: extract_struct_from_enum_variant
 //
@@ -70,11 +75,10 @@ pub(crate) fn extract_struct_from_enum_variant(
                     continue;
                 }
                 builder.edit_file(file_id);
-                let source_file = builder.make_mut(ctx.sema.parse(file_id));
                 let processed = process_references(
                     ctx,
+                    builder,
                     &mut visited_modules_set,
-                    source_file.syntax(),
                     &enum_module_def,
                     &variant_hir_name,
                     references,
@@ -84,13 +88,12 @@ pub(crate) fn extract_struct_from_enum_variant(
                 });
             }
             builder.edit_file(ctx.frange.file_id);
-            let source_file = builder.make_mut(ctx.sema.parse(ctx.frange.file_id));
             let variant = builder.make_mut(variant.clone());
             if let Some(references) = def_file_references {
                 let processed = process_references(
                     ctx,
+                    builder,
                     &mut visited_modules_set,
-                    source_file.syntax(),
                     &enum_module_def,
                     &variant_hir_name,
                     references,
@@ -100,12 +103,12 @@ pub(crate) fn extract_struct_from_enum_variant(
                 });
             }
 
-            let def = create_struct_def(variant_name.clone(), &field_list, enum_ast.visibility());
+            let def = create_struct_def(variant_name.clone(), &field_list, &enum_ast);
             let start_offset = &variant.parent_enum().syntax().clone();
             ted::insert_raw(ted::Position::before(start_offset), def.syntax());
             ted::insert_raw(ted::Position::before(start_offset), &make::tokens::blank_line());
 
-            update_variant(&variant);
+            update_variant(&variant, enum_ast.generic_param_list());
         },
     )
 }
@@ -149,7 +152,7 @@ fn existing_definition(db: &RootDatabase, variant_name: &ast::Name, variant: &Va
 fn create_struct_def(
     variant_name: ast::Name,
     field_list: &Either<ast::RecordFieldList, ast::TupleFieldList>,
-    visibility: Option<ast::Visibility>,
+    enum_: &ast::Enum,
 ) -> ast::Struct {
     let pub_vis = make::visibility_pub();
 
@@ -184,12 +187,38 @@ fn create_struct_def(
         }
     };
 
-    make::struct_(visibility, variant_name, None, field_list).clone_for_update()
+    // FIXME: This uses all the generic params of the enum, but the variant might not use all of them.
+    let strukt =
+        make::struct_(enum_.visibility(), variant_name, enum_.generic_param_list(), field_list)
+            .clone_for_update();
+
+    // copy attributes
+    ted::insert_all(
+        Position::first_child_of(strukt.syntax()),
+        enum_.attrs().map(|it| it.syntax().clone_for_update().into()).collect(),
+    );
+    strukt
 }
 
-fn update_variant(variant: &ast::Variant) -> Option<()> {
+fn update_variant(variant: &ast::Variant, generic: Option<ast::GenericParamList>) -> Option<()> {
     let name = variant.name()?;
-    let tuple_field = make::tuple_field(None, make::ty(&name.text()));
+    let ty = match generic {
+        // FIXME: This uses all the generic params of the enum, but the variant might not use all of them.
+        Some(gpl) => {
+            let gpl = gpl.clone_for_update();
+            gpl.generic_params().for_each(|gp| {
+                match gp {
+                    ast::GenericParam::LifetimeParam(it) => it.type_bound_list(),
+                    ast::GenericParam::TypeParam(it) => it.type_bound_list(),
+                    ast::GenericParam::ConstParam(_) => return,
+                }
+                .map(|it| it.remove());
+            });
+            make::ty(&format!("{}<{}>", name.text(), gpl.generic_params().join(", ")))
+        }
+        None => make::ty(&name.text()),
+    };
+    let tuple_field = make::tuple_field(None, ty);
     let replacement = make::variant(
         name,
         Some(ast::FieldList::TupleFieldList(make::tuple_field_list(iter::once(tuple_field)))),
@@ -208,18 +237,17 @@ fn apply_references(
     if let Some((scope, path)) = import {
         insert_use(&scope, mod_path_to_ast(&path), insert_use_cfg);
     }
-    ted::insert_raw(
-        ted::Position::before(segment.syntax()),
-        make::path_from_text(&format!("{}", segment)).clone_for_update().syntax(),
-    );
+    // deep clone to prevent cycle
+    let path = make::path_from_segments(iter::once(segment.clone_subtree()), false);
+    ted::insert_raw(ted::Position::before(segment.syntax()), path.clone_for_update().syntax());
     ted::insert_raw(ted::Position::before(segment.syntax()), make::token(T!['(']));
     ted::insert_raw(ted::Position::after(&node), make::token(T![')']));
 }
 
 fn process_references(
     ctx: &AssistContext,
+    builder: &mut AssistBuilder,
     visited_modules: &mut FxHashSet<Module>,
-    source_file: &SyntaxNode,
     enum_module_def: &ModuleDef,
     variant_hir_name: &Name,
     refs: Vec<FileReference>,
@@ -228,8 +256,9 @@ fn process_references(
     // and corresponding nodes up front
     refs.into_iter()
         .flat_map(|reference| {
-            let (segment, scope_node, module) =
-                reference_to_node(&ctx.sema, source_file, reference)?;
+            let (segment, scope_node, module) = reference_to_node(&ctx.sema, reference)?;
+            let segment = builder.make_mut(segment);
+            let scope_node = builder.make_syntax_mut(scope_node);
             if !visited_modules.contains(&module) {
                 let mod_path = module.find_use_path_prefixed(
                     ctx.sema.db,
@@ -251,23 +280,22 @@ fn process_references(
 
 fn reference_to_node(
     sema: &hir::Semantics<RootDatabase>,
-    source_file: &SyntaxNode,
     reference: FileReference,
 ) -> Option<(ast::PathSegment, SyntaxNode, hir::Module)> {
-    let offset = reference.range.start();
-    if let Some(path_expr) = find_node_at_offset::<ast::PathExpr>(source_file, offset) {
-        // tuple variant
-        Some((path_expr.path()?.segment()?, path_expr.syntax().parent()?))
-    } else if let Some(record_expr) = find_node_at_offset::<ast::RecordExpr>(source_file, offset) {
-        // record variant
-        Some((record_expr.path()?.segment()?, record_expr.syntax().clone()))
-    } else {
-        None
-    }
-    .and_then(|(segment, expr)| {
-        let module = sema.scope(&expr).module()?;
-        Some((segment, expr, module))
-    })
+    let segment =
+        reference.name.as_name_ref()?.syntax().parent().and_then(ast::PathSegment::cast)?;
+    let parent = segment.parent_path().syntax().parent()?;
+    let expr_or_pat = match_ast! {
+        match parent {
+            ast::PathExpr(_it) => parent.parent()?,
+            ast::RecordExpr(_it) => parent,
+            ast::TupleStructPat(_it) => parent,
+            ast::RecordPat(_it) => parent,
+            _ => return None,
+        }
+    };
+    let module = sema.scope(&expr_or_pat).module()?;
+    Some((segment, expr_or_pat, module))
 }
 
 #[cfg(test)]
@@ -278,6 +306,12 @@ mod tests {
 
     use super::*;
 
+    fn check_not_applicable(ra_fixture: &str) {
+        let fixture =
+            format!("//- /main.rs crate:main deps:core\n{}\n{}", ra_fixture, FamousDefs::FIXTURE);
+        check_assist_not_applicable(extract_struct_from_enum_variant, &fixture)
+    }
+
     #[test]
     fn test_extract_struct_several_fields_tuple() {
         check_assist(
@@ -312,6 +346,32 @@ enum A { One(One) }"#,
     }
 
     #[test]
+    fn test_extract_struct_carries_over_generics() {
+        check_assist(
+            extract_struct_from_enum_variant,
+            r"enum En<T> { Var { a: T$0 } }",
+            r#"struct Var<T>{ pub a: T }
+
+enum En<T> { Var(Var<T>) }"#,
+        );
+    }
+
+    #[test]
+    fn test_extract_struct_carries_over_attributes() {
+        check_assist(
+            extract_struct_from_enum_variant,
+            r#"#[derive(Debug)]
+#[derive(Clone)]
+enum Enum { Variant{ field: u32$0 } }"#,
+            r#"#[derive(Debug)]#[derive(Clone)] struct Variant{ pub field: u32 }
+
+#[derive(Debug)]
+#[derive(Clone)]
+enum Enum { Variant(Variant) }"#,
+        );
+    }
+
+    #[test]
     fn test_extract_struct_keep_comments_and_attrs_one_field_named() {
         check_assist(
             extract_struct_from_enum_variant,
@@ -496,7 +556,7 @@ enum E {
 }
 
 fn f() {
-    let e = E::V { i: 9, j: 2 };
+    let E::V { i, j } = E::V { i: 9, j: 2 };
 }
 "#,
             r#"
@@ -507,7 +567,34 @@ enum E {
 }
 
 fn f() {
-    let e = E::V(V { i: 9, j: 2 });
+    let E::V(V { i, j }) = E::V(V { i: 9, j: 2 });
+}
+"#,
+        )
+    }
+
+    #[test]
+    fn extract_record_fix_references2() {
+        check_assist(
+            extract_struct_from_enum_variant,
+            r#"
+enum E {
+    $0V(i32, i32)
+}
+
+fn f() {
+    let E::V(i, j) = E::V(9, 2);
+}
+"#,
+            r#"
+struct V(pub i32, pub i32);
+
+enum E {
+    V(V)
+}
+
+fn f() {
+    let E::V(V(i, j)) = E::V(V(9, 2));
 }
 "#,
         )
@@ -610,12 +697,6 @@ fn foo() {
         );
     }
 
-    fn check_not_applicable(ra_fixture: &str) {
-        let fixture =
-            format!("//- /main.rs crate:main deps:core\n{}\n{}", ra_fixture, FamousDefs::FIXTURE);
-        check_assist_not_applicable(extract_struct_from_enum_variant, &fixture)
-    }
-
     #[test]
     fn test_extract_enum_not_applicable_for_element_with_no_fields() {
         check_not_applicable("enum A { $0One }");
diff --git a/crates/ide_assists/src/handlers/extract_type_alias.rs b/crates/ide_assists/src/handlers/extract_type_alias.rs
index 442a209b9..4bccf5984 100644
--- a/crates/ide_assists/src/handlers/extract_type_alias.rs
+++ b/crates/ide_assists/src/handlers/extract_type_alias.rs
@@ -1,4 +1,7 @@
-use syntax::ast::{self, AstNode};
+use syntax::{
+    ast::{self, edit::IndentLevel, AstNode},
+    match_ast,
+};
 
 use crate::{AssistContext, AssistId, AssistKind, Assists};
 
@@ -25,7 +28,15 @@ pub(crate) fn extract_type_alias(acc: &mut Assists, ctx: &AssistContext) -> Opti
     }
 
     let node = ctx.find_node_at_range::<ast::Type>()?;
-    let insert = ctx.find_node_at_offset::<ast::Item>()?.syntax().text_range().start();
+    let item = ctx.find_node_at_offset::<ast::Item>()?;
+    let insert = match_ast! {
+        match (item.syntax().parent()?) {
+            ast::AssocItemList(it) => it.syntax().parent()?.clone(),
+            _ => item.syntax().clone(),
+        }
+    };
+    let indent = IndentLevel::from_node(&insert);
+    let insert = insert.text_range().start();
     let target = node.syntax().text_range();
 
     acc.add(
@@ -37,10 +48,14 @@ pub(crate) fn extract_type_alias(acc: &mut Assists, ctx: &AssistContext) -> Opti
             builder.replace(target, "Type");
             match ctx.config.snippet_cap {
                 Some(cap) => {
-                    builder.insert_snippet(cap, insert, format!("type $0Type = {};\n\n", node));
+                    builder.insert_snippet(
+                        cap,
+                        insert,
+                        format!("type $0Type = {};\n\n{}", node, indent),
+                    );
                 }
                 None => {
-                    builder.insert(insert, format!("type Type = {};\n\n", node));
+                    builder.insert(insert, format!("type Type = {};\n\n{}", node, indent));
                 }
             }
         },
@@ -146,4 +161,59 @@ struct S {
             "#,
         );
     }
+
+    #[test]
+    fn extract_from_impl_or_trait() {
+        // When invoked in an impl/trait, extracted type alias should be placed next to the
+        // impl/trait, not inside.
+        check_assist(
+            extract_type_alias,
+            r#"
+impl S {
+    fn f() -> $0(u8, u8)$0 {}
+}
+            "#,
+            r#"
+type $0Type = (u8, u8);
+
+impl S {
+    fn f() -> Type {}
+}
+            "#,
+        );
+        check_assist(
+            extract_type_alias,
+            r#"
+trait Tr {
+    fn f() -> $0(u8, u8)$0 {}
+}
+            "#,
+            r#"
+type $0Type = (u8, u8);
+
+trait Tr {
+    fn f() -> Type {}
+}
+            "#,
+        );
+    }
+
+    #[test]
+    fn indentation() {
+        check_assist(
+            extract_type_alias,
+            r#"
+mod m {
+    fn f() -> $0u8$0 {}
+}
+            "#,
+            r#"
+mod m {
+    type $0Type = u8;
+
+    fn f() -> Type {}
+}
+            "#,
+        );
+    }
 }
diff --git a/crates/ide_assists/src/handlers/extract_variable.rs b/crates/ide_assists/src/handlers/extract_variable.rs
index ae084c86c..46b54a5f5 100644
--- a/crates/ide_assists/src/handlers/extract_variable.rs
+++ b/crates/ide_assists/src/handlers/extract_variable.rs
@@ -36,6 +36,11 @@ pub(crate) fn extract_variable(acc: &mut Assists, ctx: &AssistContext) -> Option
         return None;
     }
     let to_extract = node.ancestors().find_map(valid_target_expr)?;
+    if let Some(ty) = ctx.sema.type_of_expr(&to_extract) {
+        if ty.is_unit() {
+            return None;
+        }
+    }
     let anchor = Anchor::from(&to_extract)?;
     let indent = anchor.syntax().prev_sibling_or_token()?.as_token()?.clone();
     let target = to_extract.syntax().text_range();
@@ -275,15 +280,23 @@ fn foo() {
         check_assist(
             extract_variable,
             r#"
-fn foo() {
+fn foo() -> i32 {
     $0bar(1 + 1)$0
 }
+
+fn bar(i: i32) -> i32 {
+    i
+}
 "#,
             r#"
-fn foo() {
+fn foo() -> i32 {
     let $0bar = bar(1 + 1);
     bar
 }
+
+fn bar(i: i32) -> i32 {
+    i
+}
 "#,
         )
     }
@@ -796,6 +809,22 @@ fn foo() {
         check_assist_not_applicable(extract_variable, "fn main() { loop { $0break$0; }; }");
     }
 
+    #[test]
+    fn test_extract_var_unit_expr_not_applicable() {
+        check_assist_not_applicable(
+            extract_variable,
+            r#"
+fn foo() {
+    let mut i = 3;
+    $0if i >= 0 {
+        i += 1;
+    } else {
+        i -= 1;
+    }$0
+}"#,
+        );
+    }
+
     // FIXME: This is not quite correct, but good enough(tm) for the sorting heuristic
     #[test]
     fn extract_var_target() {
diff --git a/crates/ide_completion/src/completions/dot.rs b/crates/ide_completion/src/completions/dot.rs
index 302c9ccbd..e0a7021fd 100644
--- a/crates/ide_completion/src/completions/dot.rs
+++ b/crates/ide_completion/src/completions/dot.rs
@@ -8,7 +8,7 @@ use crate::{context::CompletionContext, Completions};
 
 /// Complete dot accesses, i.e. fields or methods.
 pub(crate) fn complete_dot(acc: &mut Completions, ctx: &CompletionContext) {
-    let dot_receiver = match &ctx.dot_receiver {
+    let dot_receiver = match ctx.dot_receiver() {
         Some(expr) => expr,
         _ => return complete_undotted_self(acc, ctx),
     };
@@ -30,7 +30,10 @@ pub(crate) fn complete_dot(acc: &mut Completions, ctx: &CompletionContext) {
 }
 
 fn complete_undotted_self(acc: &mut Completions, ctx: &CompletionContext) {
-    if !ctx.is_trivial_path || !ctx.config.enable_self_on_the_fly {
+    if !ctx.config.enable_self_on_the_fly {
+        return;
+    }
+    if !ctx.is_trivial_path || ctx.is_path_disallowed() {
         return;
     }
     ctx.scope.process_all_names(&mut |name, def| {
diff --git a/crates/ide_completion/src/completions/flyimport.rs b/crates/ide_completion/src/completions/flyimport.rs
index df27e7a84..d72bf13d3 100644
--- a/crates/ide_completion/src/completions/flyimport.rs
+++ b/crates/ide_completion/src/completions/flyimport.rs
@@ -162,19 +162,19 @@ pub(crate) fn position_for_import<'a>(
     Some(match import_candidate {
         Some(ImportCandidate::Path(_)) => ctx.name_ref_syntax.as_ref()?.syntax(),
         Some(ImportCandidate::TraitAssocItem(_)) => ctx.path_qual.as_ref()?.syntax(),
-        Some(ImportCandidate::TraitMethod(_)) => ctx.dot_receiver.as_ref()?.syntax(),
+        Some(ImportCandidate::TraitMethod(_)) => ctx.dot_receiver()?.syntax(),
         None => ctx
             .name_ref_syntax
             .as_ref()
             .map(|name_ref| name_ref.syntax())
             .or_else(|| ctx.path_qual.as_ref().map(|path| path.syntax()))
-            .or_else(|| ctx.dot_receiver.as_ref().map(|expr| expr.syntax()))?,
+            .or_else(|| ctx.dot_receiver().map(|expr| expr.syntax()))?,
     })
 }
 
 fn import_assets(ctx: &CompletionContext, fuzzy_name: String) -> Option<ImportAssets> {
     let current_module = ctx.scope.module()?;
-    if let Some(dot_receiver) = &ctx.dot_receiver {
+    if let Some(dot_receiver) = ctx.dot_receiver() {
         ImportAssets::for_fuzzy_method_call(
             current_module,
             ctx.sema.type_of_expr(dot_receiver)?,
diff --git a/crates/ide_completion/src/completions/keyword.rs b/crates/ide_completion/src/completions/keyword.rs
index 0d035c611..1a7a484a4 100644
--- a/crates/ide_completion/src/completions/keyword.rs
+++ b/crates/ide_completion/src/completions/keyword.rs
@@ -31,7 +31,7 @@ pub(crate) fn complete_use_tree_keyword(acc: &mut Completions, ctx: &CompletionC
     }
 
     // Suggest .await syntax for types that implement Future trait
-    if let Some(receiver) = &ctx.dot_receiver {
+    if let Some(receiver) = ctx.dot_receiver() {
         if let Some(ty) = ctx.sema.type_of_expr(receiver) {
             if ty.impls_future(ctx.db) {
                 let mut item = kw_completion("await");
diff --git a/crates/ide_completion/src/completions/macro_in_item_position.rs b/crates/ide_completion/src/completions/macro_in_item_position.rs
index 202e71215..781b96ff1 100644
--- a/crates/ide_completion/src/completions/macro_in_item_position.rs
+++ b/crates/ide_completion/src/completions/macro_in_item_position.rs
@@ -5,7 +5,7 @@ use crate::{CompletionContext, Completions};
 // Ideally this should be removed and moved into `(un)qualified_path` respectively
 pub(crate) fn complete_macro_in_item_position(acc: &mut Completions, ctx: &CompletionContext) {
     // Show only macros in top level.
-    if !ctx.is_new_item {
+    if !ctx.expects_item() {
         return;
     }
 
diff --git a/crates/ide_completion/src/completions/postfix.rs b/crates/ide_completion/src/completions/postfix.rs
index 962aaf0df..86bbb58e2 100644
--- a/crates/ide_completion/src/completions/postfix.rs
+++ b/crates/ide_completion/src/completions/postfix.rs
@@ -14,6 +14,7 @@ use crate::{
     completions::postfix::format_like::add_format_like_completions,
     context::CompletionContext,
     item::{Builder, CompletionKind},
+    patterns::ImmediateLocation,
     CompletionItem, CompletionItemKind, Completions,
 };
 
@@ -22,13 +23,16 @@ pub(crate) fn complete_postfix(acc: &mut Completions, ctx: &CompletionContext) {
         return;
     }
 
-    let dot_receiver = match &ctx.dot_receiver {
-        Some(it) => it,
-        None => return,
+    let (dot_receiver, receiver_is_ambiguous_float_literal) = match &ctx.completion_location {
+        Some(ImmediateLocation::MethodCall { receiver: Some(it) }) => (it, false),
+        Some(ImmediateLocation::FieldAccess {
+            receiver: Some(it),
+            receiver_is_ambiguous_float_literal,
+        }) => (it, *receiver_is_ambiguous_float_literal),
+        _ => return,
     };
 
-    let receiver_text =
-        get_receiver_text(dot_receiver, ctx.dot_receiver_is_ambiguous_float_literal);
+    let receiver_text = get_receiver_text(dot_receiver, receiver_is_ambiguous_float_literal);
 
     let receiver_ty = match ctx.sema.type_of_expr(&dot_receiver) {
         Some(it) => it,
@@ -123,8 +127,7 @@ pub(crate) fn complete_postfix(acc: &mut Completions, ctx: &CompletionContext) {
     // The rest of the postfix completions create an expression that moves an argument,
     // so it's better to consider references now to avoid breaking the compilation
     let dot_receiver = include_references(dot_receiver);
-    let receiver_text =
-        get_receiver_text(&dot_receiver, ctx.dot_receiver_is_ambiguous_float_literal);
+    let receiver_text = get_receiver_text(&dot_receiver, receiver_is_ambiguous_float_literal);
 
     match try_enum {
         Some(try_enum) => match try_enum {
diff --git a/crates/ide_completion/src/completions/snippet.rs b/crates/ide_completion/src/completions/snippet.rs
index defc25b00..6e6a6eb92 100644
--- a/crates/ide_completion/src/completions/snippet.rs
+++ b/crates/ide_completion/src/completions/snippet.rs
@@ -29,7 +29,7 @@ pub(crate) fn complete_expr_snippet(acc: &mut Completions, ctx: &CompletionConte
 }
 
 pub(crate) fn complete_item_snippet(acc: &mut Completions, ctx: &CompletionContext) {
-    if !ctx.is_new_item {
+    if !ctx.expects_item() {
         return;
     }
     let cap = match ctx.config.snippet_cap {
diff --git a/crates/ide_completion/src/context.rs b/crates/ide_completion/src/context.rs
index 7c46c815d..6f685c02f 100644
--- a/crates/ide_completion/src/context.rs
+++ b/crates/ide_completion/src/context.rs
@@ -78,11 +78,6 @@ pub(crate) struct CompletionContext<'a> {
     pub(super) can_be_stmt: bool,
     /// `true` if we expect an expression at the cursor position.
     pub(super) is_expr: bool,
-    /// Something is typed at the "top" level, in module or impl/trait.
-    pub(super) is_new_item: bool,
-    /// The receiver if this is a field or method access, i.e. writing something.$0
-    pub(super) dot_receiver: Option<ast::Expr>,
-    pub(super) dot_receiver_is_ambiguous_float_literal: bool,
     /// If this is a call (method or function) in particular, i.e. the () are already there.
     pub(super) is_call: bool,
     /// Like `is_call`, but for tuple patterns.
@@ -158,9 +153,6 @@ impl<'a> CompletionContext<'a> {
             path_qual: None,
             can_be_stmt: false,
             is_expr: false,
-            is_new_item: false,
-            dot_receiver: None,
-            dot_receiver_is_ambiguous_float_literal: false,
             is_call: false,
             is_pattern_call: false,
             is_macro_call: false,
@@ -255,6 +247,22 @@ impl<'a> CompletionContext<'a> {
         )
     }
 
+    pub(crate) fn has_dot_receiver(&self) -> bool {
+        matches!(
+            &self.completion_location,
+            Some(ImmediateLocation::FieldAccess { receiver, .. }) | Some(ImmediateLocation::MethodCall { receiver })
+                if receiver.is_some()
+        )
+    }
+
+    pub(crate) fn dot_receiver(&self) -> Option<&ast::Expr> {
+        match &self.completion_location {
+            Some(ImmediateLocation::MethodCall { receiver })
+            | Some(ImmediateLocation::FieldAccess { receiver, .. }) => receiver.as_ref(),
+            _ => None,
+        }
+    }
+
     pub(crate) fn expects_use_tree(&self) -> bool {
         matches!(self.completion_location, Some(ImmediateLocation::Use))
     }
@@ -267,6 +275,7 @@ impl<'a> CompletionContext<'a> {
         matches!(self.completion_location, Some(ImmediateLocation::ItemList))
     }
 
+    //         fn expects_value(&self) -> bool {
     pub(crate) fn expects_expression(&self) -> bool {
         self.is_expr
     }
@@ -540,16 +549,7 @@ impl<'a> CompletionContext<'a> {
         self.name_ref_syntax =
             find_node_at_offset(original_file, name_ref.syntax().text_range().start());
 
-        let name_range = name_ref.syntax().text_range();
-        let top_node = name_ref
-            .syntax()
-            .ancestors()
-            .take_while(|it| it.text_range() == name_range)
-            .last()
-            .unwrap();
-
-        if matches!(top_node.parent().map(|it| it.kind()), Some(SOURCE_FILE) | Some(ITEM_LIST)) {
-            self.is_new_item = true;
+        if matches!(self.completion_location, Some(ImmediateLocation::ItemList)) {
             return;
         }
 
@@ -623,33 +623,8 @@ impl<'a> CompletionContext<'a> {
                 .unwrap_or(false);
             self.is_expr = path.syntax().parent().and_then(ast::PathExpr::cast).is_some();
         }
-
-        if let Some(field_expr) = ast::FieldExpr::cast(parent.clone()) {
-            // The receiver comes before the point of insertion of the fake
-            // ident, so it should have the same range in the non-modified file
-            self.dot_receiver = field_expr
-                .expr()
-                .map(|e| e.syntax().text_range())
-                .and_then(|r| find_node_with_range(original_file, r));
-            self.dot_receiver_is_ambiguous_float_literal =
-                if let Some(ast::Expr::Literal(l)) = &self.dot_receiver {
-                    match l.kind() {
-                        ast::LiteralKind::FloatNumber { .. } => l.token().text().ends_with('.'),
-                        _ => false,
-                    }
-                } else {
-                    false
-                };
-        }
-
-        if let Some(method_call_expr) = ast::MethodCallExpr::cast(parent) {
-            // As above
-            self.dot_receiver = method_call_expr
-                .receiver()
-                .map(|e| e.syntax().text_range())
-                .and_then(|r| find_node_with_range(original_file, r));
-            self.is_call = true;
-        }
+        self.is_call |=
+            matches!(self.completion_location, Some(ImmediateLocation::MethodCall { .. }));
     }
 }
 
diff --git a/crates/ide_completion/src/patterns.rs b/crates/ide_completion/src/patterns.rs
index 26516046b..080898aef 100644
--- a/crates/ide_completion/src/patterns.rs
+++ b/crates/ide_completion/src/patterns.rs
@@ -7,13 +7,13 @@ use syntax::{
     ast::{self, LoopBodyOwner},
     match_ast, AstNode, Direction, SyntaxElement,
     SyntaxKind::*,
-    SyntaxNode, SyntaxToken, TextSize, T,
+    SyntaxNode, SyntaxToken, TextRange, TextSize, T,
 };
 
 #[cfg(test)]
 use crate::test_utils::{check_pattern_is_applicable, check_pattern_is_not_applicable};
 
-/// Direct parent container of the cursor position
+/// Immediate previous node to what we are completing.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub(crate) enum ImmediatePrevSibling {
     IfExpr,
@@ -21,7 +21,7 @@ pub(crate) enum ImmediatePrevSibling {
     ImplDefType,
 }
 
-/// Direct parent container of the cursor position
+/// Direct parent "thing" of what we are currently completing.
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub(crate) enum ImmediateLocation {
     Use,
@@ -37,6 +37,15 @@ pub(crate) enum ImmediateLocation {
     // Fake file ast node
     ModDeclaration(ast::Module),
     // Original file ast node
+    MethodCall {
+        receiver: Option<ast::Expr>,
+    },
+    // Original file ast node
+    FieldAccess {
+        receiver: Option<ast::Expr>,
+        receiver_is_ambiguous_float_literal: bool,
+    },
+    // Original file ast node
     /// The record expr of the field name we are completing
     RecordExpr(ast::RecordExpr),
     // Original file ast node
@@ -164,12 +173,38 @@ pub(crate) fn determine_location(
                 Some(TRAIT) => ImmediateLocation::Trait,
                 _ => return None,
             },
-            ast::Module(it) => if it.item_list().is_none() {
+            ast::Module(it) => {
+                if it.item_list().is_none() {
                     ImmediateLocation::ModDeclaration(it)
                 } else {
-                    return None
+                    return None;
+                }
             },
             ast::Attr(it) => ImmediateLocation::Attribute(it),
+            ast::FieldExpr(it) => {
+                let receiver = it
+                    .expr()
+                    .map(|e| e.syntax().text_range())
+                    .and_then(|r| find_node_with_range(original_file, r));
+                let receiver_is_ambiguous_float_literal = if let Some(ast::Expr::Literal(l)) = &receiver {
+                    match l.kind() {
+                        ast::LiteralKind::FloatNumber { .. } => l.token().text().ends_with('.'),
+                        _ => false,
+                    }
+                } else {
+                    false
+                };
+                ImmediateLocation::FieldAccess {
+                    receiver,
+                    receiver_is_ambiguous_float_literal,
+                }
+            },
+            ast::MethodCallExpr(it) => ImmediateLocation::MethodCall {
+                receiver: it
+                    .receiver()
+                    .map(|e| e.syntax().text_range())
+                    .and_then(|r| find_node_with_range(original_file, r)),
+            },
             _ => return None,
         }
     };
@@ -194,6 +229,10 @@ fn maximize_name_ref(name_ref: &ast::NameRef) -> SyntaxNode {
     name_ref.syntax().clone()
 }
 
+fn find_node_with_range<N: AstNode>(syntax: &SyntaxNode, range: TextRange) -> Option<N> {
+    syntax.covering_element(range).ancestors().find_map(N::cast)
+}
+
 pub(crate) fn inside_impl_trait_block(element: SyntaxElement) -> bool {
     // Here we search `impl` keyword up through the all ancestors, unlike in `has_impl_parent`,
     // where we only check the first parent with different text range.
diff --git a/crates/ide_completion/src/render/function.rs b/crates/ide_completion/src/render/function.rs
index 3ec77ca0f..1abeed96d 100644
--- a/crates/ide_completion/src/render/function.rs
+++ b/crates/ide_completion/src/render/function.rs
@@ -154,7 +154,7 @@ impl<'a> FunctionRender<'a> {
         };
 
         let mut params_pats = Vec::new();
-        let params_ty = if self.ctx.completion.dot_receiver.is_some() || self.receiver.is_some() {
+        let params_ty = if self.ctx.completion.has_dot_receiver() || self.receiver.is_some() {
             self.func.method_params(self.ctx.db()).unwrap_or_default()
         } else {
             if let Some(s) = ast_params.self_param() {
diff --git a/crates/rust-analyzer/src/config.rs b/crates/rust-analyzer/src/config.rs
index ae78fd4f6..c33cdb740 100644
--- a/crates/rust-analyzer/src/config.rs
+++ b/crates/rust-analyzer/src/config.rs
@@ -92,6 +92,7 @@ config_data! {
         checkOnSave_overrideCommand: Option<Vec<String>> = "null",
 
         /// Whether to add argument snippets when completing functions.
+        /// Only applies when `#rust-analyzer.completion.addCallParenthesis#` is set.
         completion_addCallArgumentSnippets: bool = "true",
         /// Whether to add parenthesis when completing functions.
         completion_addCallParenthesis: bool      = "true",
diff --git a/crates/syntax/src/ast/make.rs b/crates/syntax/src/ast/make.rs
index 0cf170626..4c3c9661d 100644
--- a/crates/syntax/src/ast/make.rs
+++ b/crates/syntax/src/ast/make.rs
@@ -580,12 +580,11 @@ pub fn fn_(
 pub fn struct_(
     visibility: Option<ast::Visibility>,
     strukt_name: ast::Name,
-    type_params: Option<ast::GenericParamList>,
+    generic_param_list: Option<ast::GenericParamList>,
     field_list: ast::FieldList,
 ) -> ast::Struct {
     let semicolon = if matches!(field_list, ast::FieldList::TupleFieldList(_)) { ";" } else { "" };
-    let type_params =
-        if let Some(type_params) = type_params { format!("<{}>", type_params) } else { "".into() };
+    let type_params = generic_param_list.map_or_else(String::new, |it| it.to_string());
     let visibility = match visibility {
         None => String::new(),
         Some(it) => format!("{} ", it),
diff --git a/docs/user/generated_config.adoc b/docs/user/generated_config.adoc
index dbd9a3503..7f405b4d7 100644
--- a/docs/user/generated_config.adoc
+++ b/docs/user/generated_config.adoc
@@ -119,6 +119,7 @@ similar option.
 +
 --
 Whether to add argument snippets when completing functions.
+Only applies when `#rust-analyzer.completion.addCallParenthesis#` is set.
 --
 [[rust-analyzer.completion.addCallParenthesis]]rust-analyzer.completion.addCallParenthesis (default: `true`)::
 +
diff --git a/docs/user/manual.adoc b/docs/user/manual.adoc
index 1f95df56e..9a8d76700 100644
--- a/docs/user/manual.adoc
+++ b/docs/user/manual.adoc
@@ -187,6 +187,20 @@ Install it with pacman, for example:
 $ pacman -S rust-analyzer
 ----
 
+==== Gentoo Linux
+
+`rust-analyzer` is available in the GURU repository:
+
+- https://gitweb.gentoo.org/repo/proj/guru.git/tree/dev-util/rust-analyzer-bin/rust-analyzer-bin-9999.ebuild[`dev-util/rust-analyzer-bin-9999`] (the https://github.com/rust-analyzer/rust-analyzer/releases/latest[latest release] as a live binary ebuild)
+
+If not already, GURU must be enabled (e.g. using `app-eselect/eselect-repository`) and sync'd before running `emerge`:
+
+[source,bash]
+----
+$ eselect repository enable guru && emaint sync -r guru
+$ emerge rust-analyzer-bin
+----
+
 === Emacs
 
 Note this excellent https://robert.kra.hn/posts/2021-02-07_rust-with-emacs/[guide] from https://github.com/rksm[@rksm].
diff --git a/editors/code/package.json b/editors/code/package.json
index 42a06e137..4a5070d02 100644
--- a/editors/code/package.json
+++ b/editors/code/package.json
@@ -553,7 +553,7 @@
                     }
                 },
                 "rust-analyzer.completion.addCallArgumentSnippets": {
-                    "markdownDescription": "Whether to add argument snippets when completing functions.",
+                    "markdownDescription": "Whether to add argument snippets when completing functions.\nOnly applies when `#rust-analyzer.completion.addCallParenthesis#` is set.",
                     "default": true,
                     "type": "boolean"
                 },