Merge branch 'master' of github.com:rust-analyzer/rust-analyzer

.github/workflows/ci.yaml

@@ -10,7 +10,7 @@ on:
 env:
   CARGO_INCREMENTAL: 0
   CARGO_NET_RETRY: 10
-  RUN_SLOW_TESTS: 1
+  CI: 1
   RUST_BACKTRACE: short
   RUSTFLAGS: -D warnings
   RUSTUP_MAX_RETRIES: 10

.github/workflows/release.yaml

@@ -60,6 +60,10 @@ jobs:
       if: matrix.os != 'ubuntu-latest'
       run: cargo xtask dist
 
+    - name: Nightly analysis-stats check
+      if: matrix.os == 'ubuntu-latest' && github.ref != 'refs/heads/release'
+      run: ./dist/rust-analyzer-linux analysis-stats .
+
     - name: Upload artifacts
       uses: actions/upload-artifact@v1
       with:

Cargo.lock

@@ -995,6 +995,7 @@ dependencies = [
  "ra_prof",
  "ra_syntax",
  "rustc-hash",
+ "smallvec",
  "stdx",
  "test_utils",
 ]

crates/ra_assists/src/lib.rs

@@ -5,6 +5,11 @@
 //! certain context. For example, if the cursor is over `,`, a "swap `,`" assist
 //! becomes available.
 
+#[allow(unused)]
+macro_rules! eprintln {
+    ($($tt:tt)*) => { stdx::eprintln!($($tt)*) };
+}
+
 mod assist_ctx;
 mod marks;
 #[cfg(test)]

crates/ra_hir/src/diagnostics.rs

@@ -1,4 +1,4 @@
 //! FIXME: write short doc here
 pub use hir_def::diagnostics::UnresolvedModule;
 pub use hir_expand::diagnostics::{AstDiagnostic, Diagnostic, DiagnosticSink};
-pub use hir_ty::diagnostics::{MissingFields, MissingOkInTailExpr, NoSuchField};
+pub use hir_ty::diagnostics::{MissingFields, MissingMatchArms, MissingOkInTailExpr, NoSuchField};

crates/ra_hir/src/semantics.rs

@@ -9,6 +9,7 @@ use hir_def::{
     AsMacroCall, TraitId,
 };
 use hir_expand::ExpansionInfo;
+use itertools::Itertools;
 use ra_db::{FileId, FileRange};
 use ra_prof::profile;
 use ra_syntax::{
@@ -135,7 +136,6 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
         node: &SyntaxNode,
         offset: TextUnit,
     ) -> impl Iterator<Item = SyntaxNode> + '_ {
-        use itertools::Itertools;
         node.token_at_offset(offset)
             .map(|token| self.ancestors_with_macros(token.parent()))
             .kmerge_by(|node1, node2| node1.text_range().len() < node2.text_range().len())

crates/ra_hir/src/semantics/source_to_def.rs

@@ -208,12 +208,12 @@ impl SourceToDefCtx<'_, '_> {
         for container in src.cloned().ancestors_with_macros(self.db.upcast()).skip(1) {
             let res: GenericDefId = match_ast! {
                 match (container.value) {
-                    ast::FnDef(it) => { self.fn_to_def(container.with_value(it))?.into() },
+                    ast::FnDef(it) => self.fn_to_def(container.with_value(it))?.into(),
-                    ast::StructDef(it) => { self.struct_to_def(container.with_value(it))?.into() },
+                    ast::StructDef(it) => self.struct_to_def(container.with_value(it))?.into(),
-                    ast::EnumDef(it) => { self.enum_to_def(container.with_value(it))?.into() },
+                    ast::EnumDef(it) => self.enum_to_def(container.with_value(it))?.into(),
-                    ast::TraitDef(it) => { self.trait_to_def(container.with_value(it))?.into() },
+                    ast::TraitDef(it) => self.trait_to_def(container.with_value(it))?.into(),
-                    ast::TypeAliasDef(it) => { self.type_alias_to_def(container.with_value(it))?.into() },
+                    ast::TypeAliasDef(it) => self.type_alias_to_def(container.with_value(it))?.into(),
-                    ast::ImplDef(it) => { self.impl_to_def(container.with_value(it))?.into() },
+                    ast::ImplDef(it) => self.impl_to_def(container.with_value(it))?.into(),
                     _ => continue,
                 }
             };
@@ -226,9 +226,9 @@ impl SourceToDefCtx<'_, '_> {
         for container in src.cloned().ancestors_with_macros(self.db.upcast()).skip(1) {
             let res: DefWithBodyId = match_ast! {
                 match (container.value) {
-                    ast::ConstDef(it) => { self.const_to_def(container.with_value(it))?.into() },
+                    ast::ConstDef(it) => self.const_to_def(container.with_value(it))?.into(),
-                    ast::StaticDef(it) => { self.static_to_def(container.with_value(it))?.into() },
+                    ast::StaticDef(it) => self.static_to_def(container.with_value(it))?.into(),
-                    ast::FnDef(it) => { self.fn_to_def(container.with_value(it))?.into() },
+                    ast::FnDef(it) => self.fn_to_def(container.with_value(it))?.into(),
                     _ => continue,
                 }
             };

crates/ra_hir_def/src/lib.rs

@@ -7,6 +7,11 @@
 //! Note that `hir_def` is a work in progress, so not all of the above is
 //! actually true.
 
+#[allow(unused)]
+macro_rules! eprintln {
+    ($($tt:tt)*) => { stdx::eprintln!($($tt)*) };
+}
+
 pub mod db;
 
 pub mod attr;

crates/ra_hir_expand/src/builtin_derive.rs

@@ -73,9 +73,9 @@ fn parse_adt(tt: &tt::Subtree) -> Result<BasicAdtInfo, mbe::ExpandError> {
     let node = item.syntax();
     let (name, params) = match_ast! {
         match node {
-            ast::StructDef(it) => { (it.name(), it.type_param_list()) },
+            ast::StructDef(it) => (it.name(), it.type_param_list()),
-            ast::EnumDef(it) => { (it.name(), it.type_param_list()) },
+            ast::EnumDef(it) => (it.name(), it.type_param_list()),
-            ast::UnionDef(it) => { (it.name(), it.type_param_list()) },
+            ast::UnionDef(it) => (it.name(), it.type_param_list()),
             _ => {
                 debug!("unexpected node is {:?}", node);
                 return Err(mbe::ExpandError::ConversionError)

crates/ra_hir_ty/Cargo.toml

@@ -9,6 +9,7 @@ doctest = false
 
 [dependencies]
 arrayvec = "0.5.1"
+smallvec = "1.2.0"
 ena = "0.13.1"
 log = "0.4.8"
 rustc-hash = "1.1.0"

crates/ra_hir_ty/src/diagnostics.rs

@@ -6,7 +6,7 @@ use hir_expand::{db::AstDatabase, name::Name, HirFileId, InFile};
 use ra_syntax::{ast, AstNode, AstPtr, SyntaxNodePtr};
 use stdx::format_to;
 
-pub use hir_def::diagnostics::UnresolvedModule;
+pub use hir_def::{diagnostics::UnresolvedModule, expr::MatchArm};
 pub use hir_expand::diagnostics::{AstDiagnostic, Diagnostic, DiagnosticSink};
 
 #[derive(Debug)]
@@ -62,6 +62,25 @@ impl AstDiagnostic for MissingFields {
     }
 }
 
+#[derive(Debug)]
+pub struct MissingMatchArms {
+    pub file: HirFileId,
+    pub match_expr: AstPtr<ast::Expr>,
+    pub arms: AstPtr<ast::MatchArmList>,
+}
+
+impl Diagnostic for MissingMatchArms {
+    fn message(&self) -> String {
+        String::from("Missing match arm")
+    }
+    fn source(&self) -> InFile<SyntaxNodePtr> {
+        InFile { file_id: self.file, value: self.match_expr.into() }
+    }
+    fn as_any(&self) -> &(dyn Any + Send + 'static) {
+        self
+    }
+}
+
 #[derive(Debug)]
 pub struct MissingOkInTailExpr {
     pub file: HirFileId,

crates/ra_hir_ty/src/expr.rs

@@ -13,9 +13,10 @@ use rustc_hash::FxHashSet;
 
 use crate::{
     db::HirDatabase,
-    diagnostics::{MissingFields, MissingOkInTailExpr},
+    diagnostics::{MissingFields, MissingMatchArms, MissingOkInTailExpr},
     utils::variant_data,
     ApplicationTy, InferenceResult, Ty, TypeCtor,
+    _match::{is_useful, MatchCheckCtx, Matrix, PatStack, Usefulness},
 };
 
 pub use hir_def::{
@@ -51,15 +52,99 @@ impl<'a, 'b> ExprValidator<'a, 'b> {
         for e in body.exprs.iter() {
             if let (id, Expr::RecordLit { path, fields, spread }) = e {
                 self.validate_record_literal(id, path, fields, *spread, db);
+            } else if let (id, Expr::Match { expr, arms }) = e {
+                self.validate_match(id, *expr, arms, db, self.infer.clone());
             }
         }
 
         let body_expr = &body[body.body_expr];
-        if let Expr::Block { statements: _, tail: Some(t) } = body_expr {
+        if let Expr::Block { tail: Some(t), .. } = body_expr {
             self.validate_results_in_tail_expr(body.body_expr, *t, db);
         }
     }
 
+    fn validate_match(
+        &mut self,
+        id: ExprId,
+        match_expr: ExprId,
+        arms: &[MatchArm],
+        db: &dyn HirDatabase,
+        infer: Arc<InferenceResult>,
+    ) {
+        let (body, source_map): (Arc<Body>, Arc<BodySourceMap>) =
+            db.body_with_source_map(self.func.into());
+
+        let match_expr_ty = match infer.type_of_expr.get(match_expr) {
+            Some(ty) => ty,
+            // If we can't resolve the type of the match expression
+            // we cannot perform exhaustiveness checks.
+            None => return,
+        };
+
+        let cx = MatchCheckCtx { body, infer: infer.clone(), db };
+        let pats = arms.iter().map(|arm| arm.pat);
+
+        let mut seen = Matrix::empty();
+        for pat in pats {
+            // We skip any patterns whose type we cannot resolve.
+            //
+            // This could lead to false positives in this diagnostic, so
+            // it might be better to skip the entire diagnostic if we either
+            // cannot resolve a match arm or determine that the match arm has
+            // the wrong type.
+            if let Some(pat_ty) = infer.type_of_pat.get(pat) {
+                // We only include patterns whose type matches the type
+                // of the match expression. If we had a InvalidMatchArmPattern
+                // diagnostic or similar we could raise that in an else
+                // block here.
+                //
+                // When comparing the types, we also have to consider that rustc
+                // will automatically de-reference the match expression type if
+                // necessary.
+                //
+                // FIXME we should use the type checker for this.
+                if pat_ty == match_expr_ty
+                    || match_expr_ty
+                        .as_reference()
+                        .map(|(match_expr_ty, _)| match_expr_ty == pat_ty)
+                        .unwrap_or(false)
+                {
+                    // If we had a NotUsefulMatchArm diagnostic, we could
+                    // check the usefulness of each pattern as we added it
+                    // to the matrix here.
+                    let v = PatStack::from_pattern(pat);
+                    seen.push(&cx, v);
+                }
+            }
+        }
+
+        match is_useful(&cx, &seen, &PatStack::from_wild()) {
+            Ok(Usefulness::Useful) => (),
+            // if a wildcard pattern is not useful, then all patterns are covered
+            Ok(Usefulness::NotUseful) => return,
+            // this path is for unimplemented checks, so we err on the side of not
+            // reporting any errors
+            _ => return,
+        }
+
+        if let Ok(source_ptr) = source_map.expr_syntax(id) {
+            if let Some(expr) = source_ptr.value.left() {
+                let root = source_ptr.file_syntax(db.upcast());
+                if let ast::Expr::MatchExpr(match_expr) = expr.to_node(&root) {
+                    if let (Some(match_expr), Some(arms)) =
+                        (match_expr.expr(), match_expr.match_arm_list())
+                    {
+                        self.sink.push(MissingMatchArms {
+                            file: source_ptr.file_id,
+                            match_expr: AstPtr::new(&match_expr),
+                            arms: AstPtr::new(&arms),
+                        })
+                    }
+                }
+            }
+        }
+    }
+
     fn validate_record_literal(
         &mut self,
         id: ExprId,

crates/ra_hir_ty/src/infer/pat.rs

@@ -21,9 +21,13 @@ impl<'a> InferenceContext<'a> {
         subpats: &[PatId],
         expected: &Ty,
         default_bm: BindingMode,
+        id: PatId,
     ) -> Ty {
         let (ty, def) = self.resolve_variant(path);
         let var_data = def.map(|it| variant_data(self.db.upcast(), it));
+        if let Some(variant) = def {
+            self.write_variant_resolution(id.into(), variant);
+        }
         self.unify(&ty, expected);
 
         let substs = ty.substs().unwrap_or_else(Substs::empty);
@@ -152,7 +156,7 @@ impl<'a> InferenceContext<'a> {
                 Ty::apply_one(TypeCtor::Ref(*mutability), subty)
             }
             Pat::TupleStruct { path: p, args: subpats } => {
-                self.infer_tuple_struct_pat(p.as_ref(), subpats, expected, default_bm)
+                self.infer_tuple_struct_pat(p.as_ref(), subpats, expected, default_bm, pat)
             }
             Pat::Record { path: p, args: fields } => {
                 self.infer_record_pat(p.as_ref(), fields, expected, default_bm, pat)

crates/ra_hir_ty/src/infer/path.rs

@@ -67,8 +67,16 @@ impl<'a> InferenceContext<'a> {
             ValueNs::FunctionId(it) => it.into(),
             ValueNs::ConstId(it) => it.into(),
             ValueNs::StaticId(it) => it.into(),
-            ValueNs::StructId(it) => it.into(),
+            ValueNs::StructId(it) => {
-            ValueNs::EnumVariantId(it) => it.into(),
+                self.write_variant_resolution(id, it.into());
+
+                it.into()
+            }
+            ValueNs::EnumVariantId(it) => {
+                self.write_variant_resolution(id, it.into());
+
+                it.into()
+            }
         };
 
         let ty = self.db.value_ty(typable);

crates/ra_hir_ty/src/lib.rs

@@ -1,6 +1,11 @@
 //! The type system. We currently use this to infer types for completion, hover
 //! information and various assists.
 
+#[allow(unused)]
+macro_rules! eprintln {
+    ($($tt:tt)*) => { stdx::eprintln!($($tt)*) };
+}
+
 macro_rules! impl_froms {
     ($e:ident: $($v:ident $(($($sv:ident),*))?),*) => {
         $(
@@ -38,6 +43,7 @@ mod tests;
 #[cfg(test)]
 mod test_db;
 mod marks;
+mod _match;
 
 use std::ops::Deref;
 use std::sync::Arc;
@@ -855,7 +861,8 @@ pub trait TypeWalk {
         );
         self
     }
-    // /// Shifts up debruijn indices of `Ty::Bound` vars by `n`.
+
+    /// Shifts up debruijn indices of `Ty::Bound` vars by `n`.
     fn shift_bound_vars(self, n: DebruijnIndex) -> Self
     where
         Self: Sized,

crates/ra_hir_ty/src/test_db.rs

@@ -105,8 +105,9 @@ impl TestDB {
     }
 
     // FIXME: don't duplicate this
-    pub fn diagnostics(&self) -> String {
+    pub fn diagnostics(&self) -> (String, u32) {
         let mut buf = String::new();
+        let mut count = 0;
         let crate_graph = self.crate_graph();
         for krate in crate_graph.iter() {
             let crate_def_map = self.crate_def_map(krate);
@@ -133,13 +134,14 @@ impl TestDB {
                 let infer = self.infer(f.into());
                 let mut sink = DiagnosticSink::new(|d| {
                     format_to!(buf, "{:?}: {}\n", d.syntax_node(self).text(), d.message());
+                    count += 1;
                 });
                 infer.add_diagnostics(self, f, &mut sink);
                 let mut validator = ExprValidator::new(f, infer, &mut sink);
                 validator.validate_body(self);
             }
         }
-        buf
+        (buf, count)
     }
 }
 

crates/ra_hir_ty/src/tests.rs

@@ -309,7 +309,8 @@ fn no_such_field_diagnostics() {
         }
         ",
     )
-    .diagnostics();
+    .diagnostics()
+    .0;
 
     assert_snapshot!(diagnostics, @r###"
     "baz: 62": no such field

crates/ra_hir_ty/src/tests/traits.rs

@@ -2021,3 +2021,28 @@ fn main() {
     "###
     );
 }
+
+#[test]
+fn dyn_trait_through_chalk() {
+    let t = type_at(
+        r#"
+//- /main.rs
+struct Box<T> {}
+#[lang = "deref"]
+trait Deref {
+    type Target;
+}
+impl<T> Deref for Box<T> {
+    type Target = T;
+}
+trait Trait {
+    fn foo(&self);
+}
+
+fn test(x: Box<dyn Trait>) {
+    x.foo()<|>;
+}
+"#,
+    );
+    assert_eq!(t, "()");
+}

crates/ra_hir_ty/src/traits/chalk.rs

@@ -427,7 +427,12 @@ impl ToChalk for GenericPredicate {
         db: &dyn HirDatabase,
         where_clause: chalk_ir::QuantifiedWhereClause<Interner>,
     ) -> GenericPredicate {
-        match where_clause.value {
+        // we don't produce any where clauses with binders and can't currently deal with them
+        match where_clause
+            .value
+            .shifted_out(&Interner)
+            .expect("unexpected bound vars in where clause")
+        {
             chalk_ir::WhereClause::Implemented(tr) => {
                 GenericPredicate::Implemented(from_chalk(db, tr))
             }

crates/ra_ide/src/call_info.rs

@@ -109,7 +109,7 @@ impl FnCallNode {
         syntax.ancestors().find_map(|node| {
             match_ast! {
                 match node {
-                    ast::CallExpr(it) => { Some(FnCallNode::CallExpr(it)) },
+                    ast::CallExpr(it) => Some(FnCallNode::CallExpr(it)),
                     ast::MethodCallExpr(it) => {
                         let arg_list = it.arg_list()?;
                         if !syntax.text_range().is_subrange(&arg_list.syntax().text_range()) {
@@ -117,8 +117,8 @@ impl FnCallNode {
                         }
                         Some(FnCallNode::MethodCallExpr(it))
                     },
-                    ast::MacroCall(it) => { Some(FnCallNode::MacroCallExpr(it)) },
+                    ast::MacroCall(it) => Some(FnCallNode::MacroCallExpr(it)),
-                    _ => { None },
+                    _ => None,
                 }
             }
         })
@@ -127,10 +127,10 @@ impl FnCallNode {
     pub(crate) fn with_node_exact(node: &SyntaxNode) -> Option<FnCallNode> {
         match_ast! {
             match node {
-                ast::CallExpr(it) => { Some(FnCallNode::CallExpr(it)) },
+                ast::CallExpr(it) => Some(FnCallNode::CallExpr(it)),
-                ast::MethodCallExpr(it) => { Some(FnCallNode::MethodCallExpr(it)) },
+                ast::MethodCallExpr(it) => Some(FnCallNode::MethodCallExpr(it)),
-                ast::MacroCall(it) => { Some(FnCallNode::MacroCallExpr(it)) },
+                ast::MacroCall(it) => Some(FnCallNode::MacroCallExpr(it)),
-                _ => { None },
+                _ => None,
             }
         }
     }

crates/ra_ide/src/completion.rs

@@ -10,8 +10,8 @@ mod complete_pattern;
 mod complete_fn_param;
 mod complete_keyword;
 mod complete_snippet;
-mod complete_path;
+mod complete_qualified_path;
-mod complete_scope;
+mod complete_unqualified_path;
 mod complete_postfix;
 mod complete_macro_in_item_position;
 mod complete_trait_impl;
@@ -85,8 +85,8 @@ pub(crate) fn completions(
     complete_keyword::complete_use_tree_keyword(&mut acc, &ctx);
     complete_snippet::complete_expr_snippet(&mut acc, &ctx);
     complete_snippet::complete_item_snippet(&mut acc, &ctx);
-    complete_path::complete_path(&mut acc, &ctx);
+    complete_qualified_path::complete_qualified_path(&mut acc, &ctx);
-    complete_scope::complete_scope(&mut acc, &ctx);
+    complete_unqualified_path::complete_unqualified_path(&mut acc, &ctx);
     complete_dot::complete_dot(&mut acc, &ctx);
     complete_record::complete_record(&mut acc, &ctx);
     complete_pattern::complete_pattern(&mut acc, &ctx);

crates/ra_ide/src/completion/complete_fn_param.rs

@@ -18,8 +18,8 @@ pub(super) fn complete_fn_param(acc: &mut Completions, ctx: &CompletionContext)
     for node in ctx.token.parent().ancestors() {
         match_ast! {
             match node {
-                ast::SourceFile(it) => { process(it, &mut params) },
+                ast::SourceFile(it) => process(it, &mut params),
-                ast::ItemList(it) => { process(it, &mut params) },
+                ast::ItemList(it) => process(it, &mut params),
                 _ => (),
             }
         }

crates/ra_ide/src/completion/complete_keyword.rs

@@ -86,9 +86,9 @@ fn is_in_loop_body(leaf: &SyntaxToken) -> bool {
         }
         let loop_body = match_ast! {
             match node {
-                ast::ForExpr(it) => { it.loop_body() },
+                ast::ForExpr(it) => it.loop_body(),
-                ast::WhileExpr(it) => { it.loop_body() },
+                ast::WhileExpr(it) => it.loop_body(),
-                ast::LoopExpr(it) => { it.loop_body() },
+                ast::LoopExpr(it) => it.loop_body(),
                 _ => None,
             }
         };

crates/ra_ide/src/completion/complete_qualified_path.rs

@@ -6,7 +6,7 @@ use test_utils::tested_by;
 
 use crate::completion::{CompletionContext, Completions};
 
-pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
+pub(super) fn complete_qualified_path(acc: &mut Completions, ctx: &CompletionContext) {
     let path = match &ctx.path_prefix {
         Some(path) => path.clone(),
         _ => return,

crates/ra_ide/src/completion/complete_record.rs

@@ -1,12 +1,13 @@
 //! Complete fields in record literals and patterns.
-use crate::completion::{CompletionContext, Completions};
 use ra_syntax::{ast, ast::NameOwner, SmolStr};
 
+use crate::completion::{CompletionContext, Completions};
+
 pub(super) fn complete_record(acc: &mut Completions, ctx: &CompletionContext) -> Option<()> {
     let (ty, variant, already_present_fields) =
         match (ctx.record_lit_pat.as_ref(), ctx.record_lit_syntax.as_ref()) {
             (None, None) => return None,
-            (Some(_), Some(_)) => panic!("A record cannot be both a literal and a pattern"),
+            (Some(_), Some(_)) => unreachable!("A record cannot be both a literal and a pattern"),
             (Some(record_pat), _) => (
                 ctx.sema.type_of_pat(&record_pat.clone().into())?,
                 ctx.sema.resolve_record_pattern(record_pat)?,
@@ -59,9 +60,10 @@ fn pattern_ascribed_fields(record_pat: &ast::RecordPat) -> Vec<SmolStr> {
 #[cfg(test)]
 mod tests {
     mod record_lit_tests {
-        use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
         use insta::assert_debug_snapshot;
 
+        use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
+
         fn complete(code: &str) -> Vec<CompletionItem> {
             do_completion(code, CompletionKind::Reference)
         }
@@ -204,9 +206,10 @@ mod tests {
     }
 
     mod record_pat_tests {
-        use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
         use insta::assert_debug_snapshot;
 
+        use crate::completion::{test_utils::do_completion, CompletionItem, CompletionKind};
+
         fn complete(code: &str) -> Vec<CompletionItem> {
             do_completion(code, CompletionKind::Reference)
         }

crates/ra_ide/src/completion/complete_unqualified_path.rs

@@ -2,7 +2,7 @@
 
 use crate::completion::{CompletionContext, Completions};
 
-pub(super) fn complete_scope(acc: &mut Completions, ctx: &CompletionContext) {
+pub(super) fn complete_unqualified_path(acc: &mut Completions, ctx: &CompletionContext) {
     if !(ctx.is_trivial_path && !ctx.is_pat_binding_or_const) {
         return;
     }

crates/ra_ide/src/completion/completion_context.rs

@@ -50,6 +50,8 @@ pub(crate) struct CompletionContext<'a> {
     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,
+    /// If this is a macro call, i.e. the () are already there.
+    pub(super) is_macro_call: bool,
     pub(super) is_path_type: bool,
     pub(super) has_type_args: bool,
 }
@@ -102,6 +104,7 @@ impl<'a> CompletionContext<'a> {
             is_new_item: false,
             dot_receiver: None,
             is_call: false,
+            is_macro_call: false,
             is_path_type: false,
             has_type_args: false,
             dot_receiver_is_ambiguous_float_literal: false,
@@ -269,6 +272,7 @@ impl<'a> CompletionContext<'a> {
                 .and_then(ast::PathExpr::cast)
                 .and_then(|it| it.syntax().parent().and_then(ast::CallExpr::cast))
                 .is_some();
+            self.is_macro_call = path.syntax().parent().and_then(ast::MacroCall::cast).is_some();
 
             self.is_path_type = path.syntax().parent().and_then(ast::PathType::cast).is_some();
             self.has_type_args = segment.type_arg_list().is_some();

crates/ra_ide/src/completion/presentation.rs

@@ -174,7 +174,8 @@ impl Completions {
                 .set_deprecated(is_deprecated(macro_, ctx.db))
                 .detail(detail);
 
-        builder = if ctx.use_item_syntax.is_some() {
+        builder = if ctx.use_item_syntax.is_some() || ctx.is_macro_call {
+            tested_by!(dont_insert_macro_call_parens_unncessary);
             builder.insert_text(name)
         } else {
             let macro_braces_to_insert =
@@ -960,7 +961,8 @@ mod tests {
     }
 
     #[test]
-    fn dont_insert_macro_call_braces_in_use() {
+    fn dont_insert_macro_call_parens_unncessary() {
+        covers!(dont_insert_macro_call_parens_unncessary);
         assert_debug_snapshot!(
             do_reference_completion(
                 r"
@@ -986,6 +988,41 @@ mod tests {
             },
         ]
         "###
-        )
+        );
+
+        assert_debug_snapshot!(
+            do_reference_completion(
+                r"
+                //- /main.rs
+                macro_rules frobnicate {
+                    () => ()
+                }
+                fn main() {
+                    frob<|>!();
+                }
+                "
+            ),
+            @r###"
+        [
+            CompletionItem {
+                label: "frobnicate!",
+                source_range: [56; 60),
+                delete: [56; 60),
+                insert: "frobnicate",
+                kind: Macro,
+                detail: "macro_rules! frobnicate",
+            },
+            CompletionItem {
+                label: "main()",
+                source_range: [56; 60),
+                delete: [56; 60),
+                insert: "main()$0",
+                kind: Function,
+                lookup: "main",
+                detail: "fn main()",
+            },
+        ]
+        "###
+        );
     }
 }

crates/ra_ide/src/diagnostics.rs

@@ -101,6 +101,14 @@ pub(crate) fn diagnostics(db: &RootDatabase, file_id: FileId) -> Vec<Diagnostic>
             fix,
         })
     })
+    .on::<hir::diagnostics::MissingMatchArms, _>(|d| {
+        res.borrow_mut().push(Diagnostic {
+            range: d.highlight_range(),
+            message: d.message(),
+            severity: Severity::Error,
+            fix: None,
+        })
+    })
     .on::<hir::diagnostics::MissingOkInTailExpr, _>(|d| {
         let node = d.ast(db);
         let replacement = format!("Ok({})", node.syntax());
@@ -291,7 +299,7 @@ mod tests {
     fn check_no_diagnostic(content: &str) {
         let (analysis, file_id) = single_file(content);
         let diagnostics = analysis.diagnostics(file_id).unwrap();
-        assert_eq!(diagnostics.len(), 0);
+        assert_eq!(diagnostics.len(), 0, "expected no diagnostic, found one");
     }
 
     #[test]

crates/ra_ide/src/display/navigation_target.rs

@@ -399,17 +399,17 @@ pub(crate) fn docs_from_symbol(db: &RootDatabase, symbol: &FileSymbol) -> Option
 
     match_ast! {
         match node {
-            ast::FnDef(it) => { it.doc_comment_text() },
+            ast::FnDef(it) => it.doc_comment_text(),
-            ast::StructDef(it) => { it.doc_comment_text() },
+            ast::StructDef(it) => it.doc_comment_text(),
-            ast::EnumDef(it) => { it.doc_comment_text() },
+            ast::EnumDef(it) => it.doc_comment_text(),
-            ast::TraitDef(it) => { it.doc_comment_text() },
+            ast::TraitDef(it) => it.doc_comment_text(),
-            ast::Module(it) => { it.doc_comment_text() },
+            ast::Module(it) => it.doc_comment_text(),
-            ast::TypeAliasDef(it) => { it.doc_comment_text() },
+            ast::TypeAliasDef(it) => it.doc_comment_text(),
-            ast::ConstDef(it) => { it.doc_comment_text() },
+            ast::ConstDef(it) => it.doc_comment_text(),
-            ast::StaticDef(it) => { it.doc_comment_text() },
+            ast::StaticDef(it) => it.doc_comment_text(),
-            ast::RecordFieldDef(it) => { it.doc_comment_text() },
+            ast::RecordFieldDef(it) => it.doc_comment_text(),
-            ast::EnumVariant(it) => { it.doc_comment_text() },
+            ast::EnumVariant(it) => it.doc_comment_text(),
-            ast::MacroCall(it) => { it.doc_comment_text() },
+            ast::MacroCall(it) => it.doc_comment_text(),
             _ => None,
         }
     }
@@ -424,16 +424,16 @@ pub(crate) fn description_from_symbol(db: &RootDatabase, symbol: &FileSymbol) ->
 
     match_ast! {
         match node {
-            ast::FnDef(it) => { it.short_label() },
+            ast::FnDef(it) => it.short_label(),
-            ast::StructDef(it) => { it.short_label() },
+            ast::StructDef(it) => it.short_label(),
-            ast::EnumDef(it) => { it.short_label() },
+            ast::EnumDef(it) => it.short_label(),
-            ast::TraitDef(it) => { it.short_label() },
+            ast::TraitDef(it) => it.short_label(),
-            ast::Module(it) => { it.short_label() },
+            ast::Module(it) => it.short_label(),
-            ast::TypeAliasDef(it) => { it.short_label() },
+            ast::TypeAliasDef(it) => it.short_label(),
-            ast::ConstDef(it) => { it.short_label() },
+            ast::ConstDef(it) => it.short_label(),
-            ast::StaticDef(it) => { it.short_label() },
+            ast::StaticDef(it) => it.short_label(),
-            ast::RecordFieldDef(it) => { it.short_label() },
+            ast::RecordFieldDef(it) => it.short_label(),
-            ast::EnumVariant(it) => { it.short_label() },
+            ast::EnumVariant(it) => it.short_label(),
             _ => None,
         }
     }

crates/ra_ide/src/display/structure.rs

@@ -117,18 +117,18 @@ fn structure_node(node: &SyntaxNode) -> Option<StructureNode> {
 
                 decl_with_detail(it, Some(detail))
             },
-            ast::StructDef(it) => { decl(it) },
+            ast::StructDef(it) => decl(it),
-            ast::EnumDef(it) => { decl(it) },
+            ast::EnumDef(it) => decl(it),
-            ast::EnumVariant(it) => { decl(it) },
+            ast::EnumVariant(it) => decl(it),
-            ast::TraitDef(it) => { decl(it) },
+            ast::TraitDef(it) => decl(it),
-            ast::Module(it) => { decl(it) },
+            ast::Module(it) => decl(it),
             ast::TypeAliasDef(it) => {
                 let ty = it.type_ref();
                 decl_with_type_ref(it, ty)
             },
-            ast::RecordFieldDef(it) => { decl_with_ascription(it) },
+            ast::RecordFieldDef(it) => decl_with_ascription(it),
-            ast::ConstDef(it) => { decl_with_ascription(it) },
+            ast::ConstDef(it) => decl_with_ascription(it),
-            ast::StaticDef(it) => { decl_with_ascription(it) },
+            ast::StaticDef(it) => decl_with_ascription(it),
             ast::ImplDef(it) => {
                 let target_type = it.target_type()?;
                 let target_trait = it.target_trait();

crates/ra_ide/src/goto_type_definition.rs

@@ -18,9 +18,9 @@ pub(crate) fn goto_type_definition(
     let (ty, node) = sema.ancestors_with_macros(token.parent()).find_map(|node| {
         let ty = match_ast! {
             match node {
-                ast::Expr(expr) => { sema.type_of_expr(&expr)? },
+                ast::Expr(expr) => sema.type_of_expr(&expr)?,
-                ast::Pat(pat) => { sema.type_of_pat(&pat)? },
+                ast::Pat(pat) => sema.type_of_pat(&pat)?,
-                _ => { return None },
+                _ => return None,
             }
         };
 

crates/ra_ide/src/lib.rs

@@ -10,6 +10,11 @@
 // For proving that RootDatabase is RefUnwindSafe.
 #![recursion_limit = "128"]
 
+#[allow(unused)]
+macro_rules! eprintln {
+    ($($tt:tt)*) => { stdx::eprintln!($($tt)*) };
+}
+
 pub mod mock_analysis;
 mod source_change;
 

crates/ra_ide/src/marks.rs

@@ -7,4 +7,5 @@ test_utils::marks!(
     dont_complete_current_use
     test_resolve_parent_module_on_module_decl
     search_filters_by_range
+    dont_insert_macro_call_parens_unncessary
 );

crates/ra_ide/src/runnables.rs

@@ -49,8 +49,8 @@ pub(crate) fn runnables(db: &RootDatabase, file_id: FileId) -> Vec<Runnable> {
 fn runnable(sema: &Semantics<RootDatabase>, item: SyntaxNode) -> Option<Runnable> {
     match_ast! {
         match item {
-            ast::FnDef(it) => { runnable_fn(sema, it) },
+            ast::FnDef(it) => runnable_fn(sema, it),
-            ast::Module(it) => { runnable_mod(sema, it) },
+            ast::Module(it) => runnable_mod(sema, it),
             _ => None,
         }
     }

crates/ra_ide_db/src/search.rs

@@ -286,7 +286,7 @@ fn reference_access(def: &Definition, name_ref: &ast::NameRef) -> Option<Referen
                     }
                     Some(ReferenceAccess::Read)
                 },
-                _ => {None}
+                _ => None
             }
         }
     });

crates/ra_ide_db/src/symbol_index.rs

@@ -354,14 +354,14 @@ fn to_symbol(node: &SyntaxNode) -> Option<(SmolStr, SyntaxNodePtr, TextRange)> {
     }
     match_ast! {
         match node {
-            ast::FnDef(it) => { decl(it) },
+            ast::FnDef(it) => decl(it),
-            ast::StructDef(it) => { decl(it) },
+            ast::StructDef(it) => decl(it),
-            ast::EnumDef(it) => { decl(it) },
+            ast::EnumDef(it) => decl(it),
-            ast::TraitDef(it) => { decl(it) },
+            ast::TraitDef(it) => decl(it),
-            ast::Module(it) => { decl(it) },
+            ast::Module(it) => decl(it),
-            ast::TypeAliasDef(it) => { decl(it) },
+            ast::TypeAliasDef(it) => decl(it),
-            ast::ConstDef(it) => { decl(it) },
+            ast::ConstDef(it) => decl(it),
-            ast::StaticDef(it) => { decl(it) },
+            ast::StaticDef(it) => decl(it),
             ast::MacroCall(it) => {
                 if it.is_macro_rules().is_some() {
                     decl(it)

crates/ra_syntax/src/tests.rs

@@ -3,7 +3,7 @@ use std::{
     path::{Component, Path, PathBuf},
 };
 
-use test_utils::{collect_tests, dir_tests, project_dir, read_text};
+use test_utils::{collect_rust_files, dir_tests, project_dir, read_text};
 
 use crate::{fuzz, tokenize, SourceFile, SyntaxError, TextRange, TextUnit, Token};
 
@@ -13,12 +13,12 @@ fn lexer_tests() {
     // * Add tests for unicode escapes in byte-character and [raw]-byte-string literals
     // * Add tests for unescape errors
 
-    dir_tests(&test_data_dir(), &["lexer/ok"], |text, path| {
+    dir_tests(&test_data_dir(), &["lexer/ok"], "txt", |text, path| {
         let (tokens, errors) = tokenize(text);
         assert_errors_are_absent(&errors, path);
         dump_tokens_and_errors(&tokens, &errors, text)
     });
-    dir_tests(&test_data_dir(), &["lexer/err"], |text, path| {
+    dir_tests(&test_data_dir(), &["lexer/err"], "txt", |text, path| {
         let (tokens, errors) = tokenize(text);
         assert_errors_are_present(&errors, path);
         dump_tokens_and_errors(&tokens, &errors, text)
@@ -40,13 +40,13 @@ fn main() {
 
 #[test]
 fn parser_tests() {
-    dir_tests(&test_data_dir(), &["parser/inline/ok", "parser/ok"], |text, path| {
+    dir_tests(&test_data_dir(), &["parser/inline/ok", "parser/ok"], "rast", |text, path| {
         let parse = SourceFile::parse(text);
         let errors = parse.errors();
         assert_errors_are_absent(&errors, path);
         parse.debug_dump()
     });
-    dir_tests(&test_data_dir(), &["parser/err", "parser/inline/err"], |text, path| {
+    dir_tests(&test_data_dir(), &["parser/err", "parser/inline/err"], "rast", |text, path| {
         let parse = SourceFile::parse(text);
         let errors = parse.errors();
         assert_errors_are_present(&errors, path);
@@ -56,14 +56,14 @@ fn parser_tests() {
 
 #[test]
 fn parser_fuzz_tests() {
-    for (_, text) in collect_tests(&test_data_dir(), &["parser/fuzz-failures"]) {
+    for (_, text) in collect_rust_files(&test_data_dir(), &["parser/fuzz-failures"]) {
         fuzz::check_parser(&text)
     }
 }
 
 #[test]
 fn reparse_fuzz_tests() {
-    for (_, text) in collect_tests(&test_data_dir(), &["reparse/fuzz-failures"]) {
+    for (_, text) in collect_rust_files(&test_data_dir(), &["reparse/fuzz-failures"]) {
         let check = fuzz::CheckReparse::from_data(text.as_bytes()).unwrap();
         println!("{:?}", check);
         check.run();

crates/ra_syntax/src/validation.rs

@@ -88,12 +88,12 @@ pub(crate) fn validate(root: &SyntaxNode) -> Vec<SyntaxError> {
     for node in root.descendants() {
         match_ast! {
             match node {
-                ast::Literal(it) => { validate_literal(it, &mut errors) },
+                ast::Literal(it) => validate_literal(it, &mut errors),
-                ast::BlockExpr(it) => { block::validate_block_expr(it, &mut errors) },
+                ast::BlockExpr(it) => block::validate_block_expr(it, &mut errors),
-                ast::FieldExpr(it) => { validate_numeric_name(it.name_ref(), &mut errors) },
+                ast::FieldExpr(it) => validate_numeric_name(it.name_ref(), &mut errors),
-                ast::RecordField(it) => { validate_numeric_name(it.name_ref(), &mut errors) },
+                ast::RecordField(it) => validate_numeric_name(it.name_ref(), &mut errors),
-                ast::Visibility(it) => { validate_visibility(it, &mut errors) },
+                ast::Visibility(it) => validate_visibility(it, &mut errors),
-                ast::RangeExpr(it) => { validate_range_expr(it, &mut errors) },
+                ast::RangeExpr(it) => validate_range_expr(it, &mut errors),
                 _ => (),
             }
         }