Simplify

crates/hir/src/semantics.rs

@@ -897,13 +897,13 @@ impl<'db> SemanticsImpl<'db> {
     }
 
     fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db> {
-        let sa = self.analyze(node);
-        SemanticsScope { db: self.db, file_id: sa.file_id, resolver: sa.resolver }
+        let SourceAnalyzer { file_id, resolver, .. } = self.analyze(node);
+        SemanticsScope { db: self.db, file_id, resolver }
     }
 
     fn scope_at_offset(&self, node: &SyntaxNode, offset: TextSize) -> SemanticsScope<'db> {
-        let sa = self.analyze_with_offset(node, offset);
-        SemanticsScope { db: self.db, file_id: sa.file_id, resolver: sa.resolver }
+        let SourceAnalyzer { file_id, resolver, .. } = self.analyze_with_offset(node, offset);
+        SemanticsScope { db: self.db, file_id, resolver }
     }
 
     fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
@@ -924,9 +924,11 @@ impl<'db> SemanticsImpl<'db> {
     fn analyze(&self, node: &SyntaxNode) -> SourceAnalyzer {
         self.analyze_impl(node, None)
     }
+
     fn analyze_with_offset(&self, node: &SyntaxNode, offset: TextSize) -> SourceAnalyzer {
         self.analyze_impl(node, Some(offset))
     }
+
     fn analyze_impl(&self, node: &SyntaxNode, offset: Option<TextSize>) -> SourceAnalyzer {
         let _p = profile::span("Semantics::analyze_impl");
         let node = self.find_file(node.clone());

crates/hir_ty/src/method_resolution.rs

@@ -13,6 +13,7 @@ use hir_def::{
 };
 use hir_expand::name::Name;
 use rustc_hash::{FxHashMap, FxHashSet};
+use stdx::never;
 
 use crate::{
     autoderef,
@@ -322,7 +323,7 @@ pub fn def_crates(
             }};
         }
 
-    let mod_to_crate_ids = |module: ModuleId| Some(std::iter::once(module.krate()).collect());
+    let mod_to_crate_ids = |module: ModuleId| Some(iter::once(module.krate()).collect());
 
     let lang_item_targets = match ty.kind(&Interner) {
         TyKind::Adt(AdtId(def_id), _) => {
@@ -521,9 +522,16 @@ fn iterate_method_candidates_with_autoref(
     name: Option<&Name>,
     mut callback: &mut dyn FnMut(&Canonical<Ty>, AssocItemId) -> ControlFlow<()>,
 ) -> ControlFlow<()> {
+    let (receiver_ty, rest) = match deref_chain.split_first() {
+        Some((rec, rest)) => (rec.clone(), rest),
+        None => {
+            never!("received empty deref-chain");
+            return ControlFlow::Break(());
+        }
+    };
     iterate_method_candidates_by_receiver(
-        &deref_chain[0],
-        &deref_chain[1..],
+        &receiver_ty,
+        &rest,
         db,
         env.clone(),
         krate,
@@ -534,8 +542,8 @@ fn iterate_method_candidates_with_autoref(
     )?;
 
     let refed = Canonical {
-        binders: deref_chain[0].binders.clone(),
-        value: TyKind::Ref(Mutability::Not, static_lifetime(), deref_chain[0].value.clone())
+        binders: receiver_ty.binders.clone(),
+        value: TyKind::Ref(Mutability::Not, static_lifetime(), receiver_ty.value.clone())
             .intern(&Interner),
     };
 
@@ -552,9 +560,8 @@ fn iterate_method_candidates_with_autoref(
     )?;
 
     let ref_muted = Canonical {
-        binders: deref_chain[0].binders.clone(),
-        value: TyKind::Ref(Mutability::Mut, static_lifetime(), deref_chain[0].value.clone())
-            .intern(&Interner),
+        binders: receiver_ty.binders,
+        value: TyKind::Ref(Mutability::Mut, static_lifetime(), receiver_ty.value).intern(&Interner),
     };
 
     iterate_method_candidates_by_receiver(
@@ -584,7 +591,7 @@ fn iterate_method_candidates_by_receiver(
     // We're looking for methods with *receiver* type receiver_ty. These could
     // be found in any of the derefs of receiver_ty, so we have to go through
     // that.
-    for self_ty in std::iter::once(receiver_ty).chain(rest_of_deref_chain) {
+    for self_ty in iter::once(receiver_ty).chain(rest_of_deref_chain) {
         iterate_inherent_methods(
             self_ty,
             db,
@@ -597,7 +604,7 @@ fn iterate_method_candidates_by_receiver(
         )?
     }
 
-    for self_ty in std::iter::once(receiver_ty).chain(rest_of_deref_chain) {
+    for self_ty in iter::once(receiver_ty).chain(rest_of_deref_chain) {
         iterate_trait_method_candidates(
             self_ty,
             db,
@@ -659,8 +666,7 @@ fn iterate_trait_method_candidates(
         }
         _ => Vec::new(),
     };
-    let traits =
-        inherent_trait.chain(env_traits.into_iter()).chain(traits_in_scope.iter().copied());
+    let traits = inherent_trait.chain(env_traits).chain(traits_in_scope.iter().copied());
 
     'traits: for t in traits {
         let data = db.trait_data(t);
@@ -750,7 +756,7 @@ fn iterate_inherent_methods(
         let impls_for_self_ty = filter_inherent_impls_for_self_ty(&impls, &self_ty.value);
 
         for &impl_def in impls_for_self_ty {
-            for &item in db.impl_data(impl_def).items.iter() {
+            for &item in &db.impl_data(impl_def).items {
                 if !is_valid_candidate(
                     db,
                     env.clone(),

crates/ide_completion/src/context.rs

@@ -350,29 +350,28 @@ impl<'a> CompletionContext<'a> {
 impl<'a> CompletionContext<'a> {
     pub(super) fn new(
         db: &'a RootDatabase,
-        position: FilePosition,
+        position @ FilePosition { file_id, offset }: FilePosition,
         config: &'a CompletionConfig,
     ) -> Option<CompletionContext<'a>> {
         let _p = profile::span("CompletionContext::new");
         let sema = Semantics::new(db);
 
-        let original_file = sema.parse(position.file_id);
+        let original_file = sema.parse(file_id);
 
         // Insert a fake ident to get a valid parse tree. We will use this file
         // to determine context, though the original_file will be used for
         // actual completion.
         let file_with_fake_ident = {
-            let parse = db.parse(position.file_id);
-            let edit = Indel::insert(position.offset, "intellijRulezz".to_string());
+            let parse = db.parse(file_id);
+            let edit = Indel::insert(offset, "intellijRulezz".to_string());
             parse.reparse(&edit).tree()
         };
         let fake_ident_token =
-            file_with_fake_ident.syntax().token_at_offset(position.offset).right_biased().unwrap();
+            file_with_fake_ident.syntax().token_at_offset(offset).right_biased().unwrap();
 
-        let original_token =
-            original_file.syntax().token_at_offset(position.offset).left_biased()?;
+        let original_token = original_file.syntax().token_at_offset(offset).left_biased()?;
         let token = sema.descend_into_macros_single(original_token.clone());
-        let scope = sema.scope_at_offset(&token, position.offset);
+        let scope = sema.scope_at_offset(&token, offset);
         let krate = scope.krate();
         let mut locals = vec![];
         scope.process_all_names(&mut |name, scope| {
@@ -408,7 +407,7 @@ impl<'a> CompletionContext<'a> {
         ctx.expand_and_fill(
             original_file.syntax().clone(),
             file_with_fake_ident.syntax().clone(),
-            position.offset,
+            offset,
             fake_ident_token,
         );
         Some(ctx)