prefer default over new

crates/base-db/src/change.rs

@@ -34,10 +34,6 @@ impl fmt::Debug for FileChange {
 }
 
 impl FileChange {
-    pub fn new() -> Self {
-        FileChange::default()
-    }
-
     pub fn set_roots(&mut self, roots: Vec<SourceRoot>) {
         self.roots = Some(roots);
     }

crates/hir-def/src/dyn_map.rs

@@ -112,6 +112,10 @@ pub struct Key<K, V, P = (K, V)> {
 }
 
 impl<K, V, P> Key<K, V, P> {
+    #[allow(
+        clippy::new_without_default,
+        reason = "this a const fn, so it can't be default yet. See <https://github.com/rust-lang/rust/issues/63065>"
+    )]
     pub(crate) const fn new() -> Key<K, V, P> {
         Key { _phantom: PhantomData }
     }
@@ -148,16 +152,11 @@ impl<K: Hash + Eq + 'static, V: 'static> Policy for (K, V) {
     }
 }
 
+#[derive(Default)]
 pub struct DynMap {
     pub(crate) map: Map,
 }
 
-impl Default for DynMap {
-    fn default() -> Self {
-        DynMap { map: Map::new() }
-    }
-}
-
 #[repr(transparent)]
 pub struct KeyMap<KEY> {
     map: DynMap,

crates/hir-def/src/expr_store/lower.rs

@@ -2053,7 +2053,7 @@ impl ExprCollector<'_> {
         f: ast::FormatArgsExpr,
         syntax_ptr: AstPtr<ast::Expr>,
     ) -> ExprId {
-        let mut args = FormatArgumentsCollector::new();
+        let mut args = FormatArgumentsCollector::default();
         f.args().for_each(|arg| {
             args.add(FormatArgument {
                 kind: match arg.name() {

crates/hir-def/src/hir/format_args.rs

@@ -460,10 +460,6 @@ impl FormatArgumentsCollector {
         }
     }
 
-    pub fn new() -> Self {
-        Default::default()
-    }
-
     pub fn add(&mut self, arg: FormatArgument) -> usize {
         let index = self.arguments.len();
         if let Some(name) = arg.kind.ident() {

crates/hir-expand/src/change.rs

@@ -14,10 +14,6 @@ pub struct ChangeWithProcMacros {
 }
 
 impl ChangeWithProcMacros {
-    pub fn new() -> Self {
-        Self::default()
-    }
-
     pub fn apply(self, db: &mut impl ExpandDatabase) {
         let crates_id_map = self.source_change.apply(db);
         if let Some(proc_macros) = self.proc_macros {

crates/ide-assists/src/handlers/add_braces.rs

@@ -39,7 +39,7 @@ pub(crate) fn add_braces(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<(
         },
         expr.syntax().text_range(),
         |builder| {
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             let mut editor = builder.make_editor(expr.syntax());
 
             let block_expr = make.block_expr(None, Some(expr.clone()));

crates/ide-assists/src/handlers/add_missing_match_arms.rs

@@ -77,7 +77,7 @@ pub(crate) fn add_missing_match_arms(acc: &mut Assists, ctx: &AssistContext<'_>)
 
     let cfg = ctx.config.import_path_config();
 
-    let make = SyntaxFactory::new();
+    let make = SyntaxFactory::with_mappings();
 
     let module = ctx.sema.scope(expr.syntax())?.module();
     let (mut missing_pats, is_non_exhaustive, has_hidden_variants): (
@@ -467,7 +467,7 @@ fn build_pat(
             let fields = var.fields(db);
             let pat: ast::Pat = match var.kind(db) {
                 hir::StructKind::Tuple => {
-                    let mut name_generator = suggest_name::NameGenerator::new();
+                    let mut name_generator = suggest_name::NameGenerator::default();
                     let pats = fields.into_iter().map(|f| {
                         let name = name_generator.for_type(&f.ty(db), db, edition);
                         match name {

crates/ide-assists/src/handlers/add_turbo_fish.rs

@@ -141,7 +141,7 @@ pub(crate) fn add_turbo_fish(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
         |builder| {
             builder.trigger_parameter_hints();
 
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             let mut editor = match &turbofish_target {
                 Either::Left(it) => builder.make_editor(it.syntax()),
                 Either::Right(it) => builder.make_editor(it.syntax()),

crates/ide-assists/src/handlers/apply_demorgan.rs

@@ -64,7 +64,7 @@ pub(crate) fn apply_demorgan(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
         _ => return None,
     };
 
-    let make = SyntaxFactory::new();
+    let make = SyntaxFactory::with_mappings();
 
     let demorganed = bin_expr.clone_subtree();
     let mut editor = SyntaxEditor::new(demorganed.syntax().clone());
@@ -111,7 +111,7 @@ pub(crate) fn apply_demorgan(acc: &mut Assists, ctx: &AssistContext<'_>) -> Opti
         "Apply De Morgan's law",
         op_range,
         |builder| {
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             let paren_expr = bin_expr.syntax().parent().and_then(ast::ParenExpr::cast);
             let neg_expr = paren_expr
                 .clone()
@@ -194,7 +194,7 @@ pub(crate) fn apply_demorgan_iterator(acc: &mut Assists, ctx: &AssistContext<'_>
         label,
         op_range,
         |builder| {
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             let mut editor = builder.make_editor(method_call.syntax());
             // replace the method name
             let new_name = match name.text().as_str() {

crates/ide-assists/src/handlers/convert_bool_then.rs

@@ -98,7 +98,7 @@ pub(crate) fn convert_if_to_bool_then(acc: &mut Assists, ctx: &AssistContext<'_>
             let closure_body = ast::Expr::cast(edit.new_root().clone()).unwrap();
 
             let mut editor = builder.make_editor(expr.syntax());
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             let closure_body = match closure_body {
                 ast::Expr::BlockExpr(block) => unwrap_trivial_block(block),
                 e => e,
@@ -216,7 +216,7 @@ pub(crate) fn convert_bool_then_to_if(acc: &mut Assists, ctx: &AssistContext<'_>
             let closure_body = ast::BlockExpr::cast(edit.new_root().clone()).unwrap();
 
             let mut editor = builder.make_editor(mcall.syntax());
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
 
             let cond = match &receiver {
                 ast::Expr::ParenExpr(expr) => expr.expr().unwrap_or(receiver),

crates/ide-assists/src/handlers/convert_for_to_while_let.rs

@@ -51,7 +51,7 @@ pub(crate) fn convert_for_loop_to_while_let(
         "Replace this for loop with `while let`",
         for_loop.syntax().text_range(),
         |builder| {
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             let mut editor = builder.make_editor(for_loop.syntax());
 
             let (iterable, method) = if impls_core_iter(&ctx.sema, &iterable) {

crates/ide-assists/src/handlers/extract_variable.rs

@@ -170,7 +170,7 @@ pub(crate) fn extract_variable(acc: &mut Assists, ctx: &AssistContext<'_>) -> Op
             |edit| {
                 let (var_name, expr_replace) = kind.get_name_and_expr(ctx, &to_extract);
 
-                let make = SyntaxFactory::new();
+                let make = SyntaxFactory::with_mappings();
                 let mut editor = edit.make_editor(&expr_replace);
 
                 let pat_name = make.name(&var_name);

crates/ide-assists/src/handlers/flip_binexpr.rs

@@ -48,7 +48,7 @@ pub(crate) fn flip_binexpr(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
         op_token.text_range(),
         |builder| {
             let mut editor = builder.make_editor(&expr.syntax().parent().unwrap());
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             if let FlipAction::FlipAndReplaceOp(binary_op) = action {
                 editor.replace(op_token, make.token(binary_op))
             };

crates/ide-assists/src/handlers/flip_comma.rs

@@ -101,7 +101,7 @@ fn flip_tree(tree: ast::TokenTree, comma: SyntaxToken) -> (ast::TokenTree, Synta
     ]
     .concat();
 
-    let make = SyntaxFactory::new();
+    let make = SyntaxFactory::with_mappings();
     let new_token_tree = make.token_tree(tree.left_delimiter_token().unwrap().kind(), result);
     (new_token_tree, make.finish_with_mappings())
 }

crates/ide-assists/src/handlers/generate_enum_variant.rs

@@ -60,7 +60,7 @@ pub(crate) fn generate_enum_variant(acc: &mut Assists, ctx: &AssistContext<'_>)
 
     acc.add(AssistId::generate("generate_enum_variant"), "Generate variant", target, |builder| {
         let mut editor = builder.make_editor(enum_node.syntax());
-        let make = SyntaxFactory::new();
+        let make = SyntaxFactory::with_mappings();
         let field_list = parent.make_field_list(ctx, &make);
         let variant = make.variant(None, make.name(&name_ref.text()), field_list, None);
         if let Some(it) = enum_node.variant_list() {

crates/ide-assists/src/handlers/inline_local_variable.rs

@@ -91,7 +91,7 @@ pub(crate) fn inline_local_variable(acc: &mut Assists, ctx: &AssistContext<'_>)
                 }
             }
 
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
 
             for (name, should_wrap) in wrap_in_parens {
                 let replacement = if should_wrap {

crates/ide-assists/src/handlers/introduce_named_type_parameter.rs

@@ -24,7 +24,7 @@ pub(crate) fn introduce_named_type_parameter(
     let fn_ = param.syntax().ancestors().nth(2).and_then(ast::Fn::cast)?;
     let type_bound_list = impl_trait_type.type_bound_list()?;
 
-    let make = SyntaxFactory::new();
+    let make = SyntaxFactory::with_mappings();
     let target = fn_.syntax().text_range();
     acc.add(
         AssistId::refactor_rewrite("introduce_named_type_parameter"),

crates/ide-assists/src/handlers/remove_parentheses.rs

@@ -54,7 +54,7 @@ pub(crate) fn remove_parentheses(acc: &mut Assists, ctx: &AssistContext<'_>) ->
                 None => false,
             };
             if need_to_add_ws {
-                let make = SyntaxFactory::new();
+                let make = SyntaxFactory::with_mappings();
                 editor.insert(Position::before(parens.syntax()), make.whitespace(" "));
                 editor.add_mappings(make.finish_with_mappings());
             }

crates/ide-assists/src/handlers/replace_if_let_with_match.rs

@@ -105,7 +105,7 @@ pub(crate) fn replace_if_let_with_match(acc: &mut Assists, ctx: &AssistContext<'
         format!("Replace if{let_} with match"),
         available_range,
         move |builder| {
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             let match_expr = {
                 let else_arm = make_else_arm(ctx, &make, else_block, &cond_bodies);
                 let make_match_arm = |(pat, body): (_, ast::BlockExpr)| {
@@ -253,7 +253,7 @@ pub(crate) fn replace_match_with_if_let(acc: &mut Assists, ctx: &AssistContext<'
         format!("Replace match with if{let_}"),
         match_expr.syntax().text_range(),
         move |builder| {
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             let make_block_expr = |expr: ast::Expr| {
                 // Blocks with modifiers (unsafe, async, etc.) are parsed as BlockExpr, but are
                 // formatted without enclosing braces. If we encounter such block exprs,

crates/ide-assists/src/handlers/replace_let_with_if_let.rs

@@ -43,7 +43,7 @@ pub(crate) fn replace_let_with_if_let(acc: &mut Assists, ctx: &AssistContext<'_>
         target,
         |builder| {
             let mut editor = builder.make_editor(let_stmt.syntax());
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
             let ty = ctx.sema.type_of_expr(&init);
             let pat = if let_stmt.let_else().is_some() {
                 // Do not add the wrapper type that implements `Try`,

crates/ide-assists/src/handlers/unwrap_return_type.rs

@@ -67,7 +67,7 @@ pub(crate) fn unwrap_return_type(acc: &mut Assists, ctx: &AssistContext<'_>) ->
 
     acc.add(kind.assist_id(), kind.label(), type_ref.syntax().text_range(), |builder| {
         let mut editor = builder.make_editor(&parent);
-        let make = SyntaxFactory::new();
+        let make = SyntaxFactory::with_mappings();
 
         let mut exprs_to_unwrap = Vec::new();
         let tail_cb = &mut |e: &_| tail_cb_impl(&mut exprs_to_unwrap, e);

crates/ide-assists/src/handlers/wrap_return_type.rs

@@ -77,7 +77,7 @@ pub(crate) fn wrap_return_type(acc: &mut Assists, ctx: &AssistContext<'_>) -> Op
             type_ref.syntax().text_range(),
             |builder| {
                 let mut editor = builder.make_editor(&parent);
-                let make = SyntaxFactory::new();
+                let make = SyntaxFactory::with_mappings();
                 let alias = wrapper_alias(ctx, &make, &core_wrapper, type_ref, kind.symbol());
                 let new_return_ty = alias.unwrap_or_else(|| match kind {
                     WrapperKind::Option => make.ty_option(type_ref.clone()),

crates/ide-completion/src/completions/pattern.rs

@@ -48,7 +48,7 @@ pub(crate) fn complete_pattern(
 
     // Suggest name only in let-stmt and fn param
     if pattern_ctx.should_suggest_name {
-        let mut name_generator = suggest_name::NameGenerator::new();
+        let mut name_generator = suggest_name::NameGenerator::default();
         if let Some(suggested) = ctx
             .expected_type
             .as_ref()

crates/ide-db/src/prime_caches/topologic_sort.rs

@@ -7,14 +7,20 @@ pub(crate) struct TopologicSortIterBuilder<T> {
     nodes: FxHashMap<T, Entry<T>>,
 }
 
+// this implementation has different bounds on T than would be implied by #[derive(Default)]
+impl<T> Default for TopologicSortIterBuilder<T>
+where
+    T: Copy + Eq + PartialEq + Hash,
+{
+    fn default() -> Self {
+        Self { nodes: Default::default() }
+    }
+}
+
 impl<T> TopologicSortIterBuilder<T>
 where
     T: Copy + Eq + PartialEq + Hash,
 {
-    fn new() -> Self {
-        Self { nodes: Default::default() }
-    }
-
     fn get_or_create_entry(&mut self, item: T) -> &mut Entry<T> {
         self.nodes.entry(item).or_default()
     }
@@ -54,7 +60,7 @@ where
     T: Copy + Eq + PartialEq + Hash,
 {
     pub(crate) fn builder() -> TopologicSortIterBuilder<T> {
-        TopologicSortIterBuilder::new()
+        TopologicSortIterBuilder::default()
     }
 
     pub(crate) fn pending(&self) -> usize {

crates/ide-db/src/source_change.rs

@@ -469,7 +469,7 @@ impl SourceChangeBuilder {
     }
 
     fn add_snippet_annotation(&mut self, kind: AnnotationSnippet) -> SyntaxAnnotation {
-        let annotation = SyntaxAnnotation::new();
+        let annotation = SyntaxAnnotation::default();
         self.snippet_annotations.push((kind, annotation));
         self.source_change.is_snippet = true;
         annotation

crates/ide-db/src/syntax_helpers/suggest_name.rs

@@ -96,21 +96,16 @@ pub struct NameGenerator {
 }
 
 impl NameGenerator {
-    /// Create a new empty generator
-    pub fn new() -> Self {
-        Self { pool: FxHashMap::default() }
-    }
-
     /// Create a new generator with existing names. When suggesting a name, it will
     /// avoid conflicts with existing names.
     pub fn new_with_names<'a>(existing_names: impl Iterator<Item = &'a str>) -> Self {
-        let mut generator = Self::new();
+        let mut generator = Self::default();
         existing_names.for_each(|name| generator.insert(name));
         generator
     }
 
     pub fn new_from_scope_locals(scope: Option<SemanticsScope<'_>>) -> Self {
-        let mut generator = Self::new();
+        let mut generator = Self::default();
         if let Some(scope) = scope {
             scope.process_all_names(&mut |name, scope| {
                 if let hir::ScopeDef::Local(_) = scope {
@@ -471,7 +466,7 @@ mod tests {
             frange.range,
             "selection is not an expression(yet contained in one)"
         );
-        let name = NameGenerator::new().for_variable(&expr, &sema);
+        let name = NameGenerator::default().for_variable(&expr, &sema);
         assert_eq!(&name, expected);
     }
 
@@ -1118,7 +1113,7 @@ fn main() {
 
     #[test]
     fn conflicts_with_existing_names() {
-        let mut generator = NameGenerator::new();
+        let mut generator = NameGenerator::default();
         assert_eq!(generator.suggest_name("a"), "a");
         assert_eq!(generator.suggest_name("a"), "a1");
         assert_eq!(generator.suggest_name("a"), "a2");

crates/ide-diagnostics/src/handlers/type_mismatch.rs

@@ -231,7 +231,7 @@ fn remove_unnecessary_wrapper(
                 .and_then(Either::<ast::ReturnExpr, ast::StmtList>::cast)?;
 
             editor = builder.make_editor(parent.syntax());
-            let make = SyntaxFactory::new();
+            let make = SyntaxFactory::with_mappings();
 
             match parent {
                 Either::Left(ret_expr) => {

crates/ide/src/lib.rs

@@ -238,7 +238,7 @@ impl Analysis {
         file_set.insert(file_id, VfsPath::new_virtual_path("/main.rs".to_owned()));
         let source_root = SourceRoot::new_local(file_set);
 
-        let mut change = ChangeWithProcMacros::new();
+        let mut change = ChangeWithProcMacros::default();
         change.set_roots(vec![source_root]);
         let mut crate_graph = CrateGraphBuilder::default();
         // FIXME: cfg options

crates/intern/src/lib.rs

@@ -177,7 +177,10 @@ pub struct InternStorage<T: ?Sized> {
     map: OnceLock<InternMap<T>>,
 }
 
-#[allow(clippy::new_without_default)] // this a const fn, so it can't be default
+#[allow(
+    clippy::new_without_default,
+    reason = "this a const fn, so it can't be default yet. See <https://github.com/rust-lang/rust/issues/63065>"
+)]
 impl<T: ?Sized> InternStorage<T> {
     pub const fn new() -> Self {
         Self { map: OnceLock::new() }

crates/load-cargo/src/lib.rs

@@ -426,7 +426,7 @@ fn load_crate_graph(
 ) -> RootDatabase {
     let lru_cap = std::env::var("RA_LRU_CAP").ok().and_then(|it| it.parse::<u16>().ok());
     let mut db = RootDatabase::new(lru_cap);
-    let mut analysis_change = ChangeWithProcMacros::new();
+    let mut analysis_change = ChangeWithProcMacros::default();
 
     db.enable_proc_attr_macros();
 

crates/proc-macro-srv/proc-macro-test/imp/src/lib.rs

@@ -90,7 +90,7 @@ pub fn attr_error(args: TokenStream, item: TokenStream) -> TokenStream {
 
 #[proc_macro_derive(DeriveEmpty)]
 pub fn derive_empty(_item: TokenStream) -> TokenStream {
-    TokenStream::new()
+    TokenStream::default()
 }
 
 #[proc_macro_derive(DerivePanic)]

crates/proc-macro-srv/src/proc_macros.rs

@@ -26,7 +26,7 @@ impl ProcMacros {
         let parsed_body = crate::server_impl::TokenStream::with_subtree(macro_body);
 
         let parsed_attributes = attributes
-            .map_or_else(crate::server_impl::TokenStream::new, |attr| {
+            .map_or_else(crate::server_impl::TokenStream::default, |attr| {
                 crate::server_impl::TokenStream::with_subtree(attr)
             });
 

crates/proc-macro-srv/src/server_impl/rust_analyzer_span.rs

@@ -212,7 +212,7 @@ impl server::TokenStream for RaSpanServer {
         base: Option<Self::TokenStream>,
         trees: Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>>,
     ) -> Self::TokenStream {
-        let mut builder = TokenStreamBuilder::new();
+        let mut builder = TokenStreamBuilder::default();
         if let Some(base) = base {
             builder.push(base);
         }
@@ -227,7 +227,7 @@ impl server::TokenStream for RaSpanServer {
         base: Option<Self::TokenStream>,
         streams: Vec<Self::TokenStream>,
     ) -> Self::TokenStream {
-        let mut builder = TokenStreamBuilder::new();
+        let mut builder = TokenStreamBuilder::default();
         if let Some(base) = base {
             builder.push(base);
         }

crates/proc-macro-srv/src/server_impl/token_id.rs

@@ -190,7 +190,7 @@ impl server::TokenStream for TokenIdServer {
         base: Option<Self::TokenStream>,
         trees: Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>>,
     ) -> Self::TokenStream {
-        let mut builder = TokenStreamBuilder::new();
+        let mut builder = TokenStreamBuilder::default();
         if let Some(base) = base {
             builder.push(base);
         }
@@ -205,7 +205,7 @@ impl server::TokenStream for TokenIdServer {
         base: Option<Self::TokenStream>,
         streams: Vec<Self::TokenStream>,
     ) -> Self::TokenStream {
-        let mut builder = TokenStreamBuilder::new();
+        let mut builder = TokenStreamBuilder::default();
         if let Some(base) = base {
             builder.push(base);
         }

crates/proc-macro-srv/src/server_impl/token_stream.rs

@@ -9,6 +9,13 @@ pub struct TokenStream<S> {
     pub(super) token_trees: Vec<tt::TokenTree<S>>,
 }
 
+// #[derive(Default)] would mean that `S: Default`.
+impl<S> Default for TokenStream<S> {
+    fn default() -> Self {
+        Self { token_trees: Default::default() }
+    }
+}
+
 impl<S: std::fmt::Debug + Copy> std::fmt::Debug for TokenStream<S> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         f.debug_struct("TokenStream")
@@ -17,17 +24,7 @@ impl<S: std::fmt::Debug + Copy> std::fmt::Debug for TokenStream<S> {
     }
 }
 
-impl<S> Default for TokenStream<S> {
-    fn default() -> Self {
-        Self { token_trees: vec![] }
-    }
-}
-
 impl<S: Copy> TokenStream<S> {
-    pub(crate) fn new() -> Self {
-        TokenStream::default()
-    }
-
     pub(crate) fn with_subtree(subtree: TopSubtree<S>) -> Self {
         let delimiter_kind = subtree.top_subtree().delimiter.kind;
         let mut token_trees = subtree.0;
@@ -145,10 +142,6 @@ pub(super) mod token_stream_impls {
 }
 
 impl<S: Copy> TokenStreamBuilder<S> {
-    pub(super) fn new() -> TokenStreamBuilder<S> {
-        TokenStreamBuilder { acc: TokenStream::new() }
-    }
-
     pub(super) fn push(&mut self, stream: TokenStream<S>) {
         self.acc.token_trees.extend(stream.token_trees)
     }
@@ -157,3 +150,9 @@ impl<S: Copy> TokenStreamBuilder<S> {
         self.acc
     }
 }
+
+impl<S: Copy> Default for TokenStreamBuilder<S> {
+    fn default() -> Self {
+        Self { acc: TokenStream::default() }
+    }
+}

crates/rust-analyzer/src/cli/rustc_tests.rs

@@ -139,7 +139,7 @@ impl Tester {
             FxHashMap::default()
         };
         let text = read_to_string(&p).unwrap();
-        let mut change = ChangeWithProcMacros::new();
+        let mut change = ChangeWithProcMacros::default();
         // Ignore unstable tests, since they move too fast and we do not intend to support all of them.
         let mut ignore_test = text.contains("#![feature");
         // Ignore test with extern crates, as this infra don't support them yet.

crates/rust-analyzer/src/cli/scip.rs

@@ -128,7 +128,7 @@ impl flags::Scip {
             };
 
         // Generates symbols from token monikers.
-        let mut symbol_generator = SymbolGenerator::new();
+        let mut symbol_generator = SymbolGenerator::default();
 
         for StaticIndexedFile { file_id, tokens, .. } in si.files {
             symbol_generator.clear_document_local_state();
@@ -417,16 +417,13 @@ struct TokenSymbols {
     is_inherent_impl: bool,
 }
 
+#[derive(Default)]
 struct SymbolGenerator {
     token_to_symbols: FxHashMap<TokenId, Option<TokenSymbols>>,
     local_count: usize,
 }
 
 impl SymbolGenerator {
-    fn new() -> Self {
-        SymbolGenerator { token_to_symbols: FxHashMap::default(), local_count: 0 }
-    }
-
     fn clear_document_local_state(&mut self) {
         self.local_count = 0;
     }

crates/rust-analyzer/src/global_state.rs

@@ -299,7 +299,7 @@ impl GlobalState {
             FxHashMap::default();
 
         let (change, modified_rust_files, workspace_structure_change) = {
-            let mut change = ChangeWithProcMacros::new();
+            let mut change = ChangeWithProcMacros::default();
             let mut guard = self.vfs.write();
             let changed_files = guard.0.take_changes();
             if changed_files.is_empty() {

crates/rust-analyzer/src/integrated_benchmarks.rs

@@ -86,7 +86,7 @@ fn integrated_highlighting_benchmark() {
             "self.data.cargo_buildScripts_rebuildOnSave",
             "self. data. cargo_buildScripts_rebuildOnSave",
         );
-        let mut change = ChangeWithProcMacros::new();
+        let mut change = ChangeWithProcMacros::default();
         change.change_file(file_id, Some(text));
         host.apply_change(change);
     }
@@ -149,7 +149,7 @@ fn integrated_completion_benchmark() {
         let completion_offset =
             patch(&mut text, "db.struct_data(self.id)", "sel;\ndb.struct_data(self.id)")
                 + "sel".len();
-        let mut change = ChangeWithProcMacros::new();
+        let mut change = ChangeWithProcMacros::default();
         change.change_file(file_id, Some(text));
         host.apply_change(change);
         completion_offset
@@ -200,7 +200,7 @@ fn integrated_completion_benchmark() {
         let completion_offset =
             patch(&mut text, "sel;\ndb.struct_data(self.id)", ";sel;\ndb.struct_data(self.id)")
                 + ";sel".len();
-        let mut change = ChangeWithProcMacros::new();
+        let mut change = ChangeWithProcMacros::default();
         change.change_file(file_id, Some(text));
         host.apply_change(change);
         completion_offset
@@ -250,7 +250,7 @@ fn integrated_completion_benchmark() {
         let completion_offset =
             patch(&mut text, "sel;\ndb.struct_data(self.id)", "self.;\ndb.struct_data(self.id)")
                 + "self.".len();
-        let mut change = ChangeWithProcMacros::new();
+        let mut change = ChangeWithProcMacros::default();
         change.change_file(file_id, Some(text));
         host.apply_change(change);
         completion_offset
@@ -367,7 +367,7 @@ fn integrated_diagnostics_benchmark() {
         let _it = stdx::timeit("change");
         let mut text = host.analysis().file_text(file_id).unwrap().to_string();
         patch(&mut text, "db.struct_data(self.id)", "();\ndb.struct_data(self.id)");
-        let mut change = ChangeWithProcMacros::new();
+        let mut change = ChangeWithProcMacros::default();
         change.change_file(file_id, Some(text));
         host.apply_change(change);
     };

crates/rust-analyzer/src/reload.rs

@@ -739,7 +739,7 @@ impl GlobalState {
 
             ws_to_crate_graph(&self.workspaces, self.config.extra_env(None), load)
         };
-        let mut change = ChangeWithProcMacros::new();
+        let mut change = ChangeWithProcMacros::default();
         if initial_build || !self.config.expand_proc_macros() {
             if self.config.expand_proc_macros() {
                 change.set_proc_macros(

crates/stdx/src/anymap.rs

@@ -101,20 +101,15 @@ pub struct Map<A: ?Sized + Downcast = dyn Any> {
 /// `Map::new()` doesn’t seem to be happy to infer that it should go with the default
 /// value. It’s a bit sad, really. Ah well, I guess this approach will do.
 pub type AnyMap = Map<dyn Any>;
+
 impl<A: ?Sized + Downcast> Default for Map<A> {
     #[inline]
     fn default() -> Map<A> {
-        Map::new()
+        Map { raw: RawMap::with_hasher(Default::default()) }
     }
 }
 
 impl<A: ?Sized + Downcast> Map<A> {
-    /// Create an empty collection.
-    #[inline]
-    pub fn new() -> Map<A> {
-        Map { raw: RawMap::with_hasher(Default::default()) }
-    }
-
     /// Returns a reference to the value stored in the collection for the type `T`,
     /// if it exists.
     #[inline]

crates/syntax/src/ast/syntax_factory.rs

@@ -19,8 +19,8 @@ pub struct SyntaxFactory {
 
 impl SyntaxFactory {
     /// Creates a new [`SyntaxFactory`], generating mappings between input nodes and generated nodes.
-    pub fn new() -> Self {
-        Self { mappings: Some(RefCell::new(SyntaxMapping::new())) }
+    pub fn with_mappings() -> Self {
+        Self { mappings: Some(RefCell::new(SyntaxMapping::default())) }
     }
 
     /// Creates a [`SyntaxFactory`] without generating mappings.

crates/syntax/src/syntax_editor.rs

@@ -33,7 +33,7 @@ pub struct SyntaxEditor {
 impl SyntaxEditor {
     /// Creates a syntax editor to start editing from `root`
     pub fn new(root: SyntaxNode) -> Self {
-        Self { root, changes: vec![], mappings: SyntaxMapping::new(), annotations: vec![] }
+        Self { root, changes: vec![], mappings: SyntaxMapping::default(), annotations: vec![] }
     }
 
     pub fn add_annotation(&mut self, element: impl Element, annotation: SyntaxAnnotation) {
@@ -151,9 +151,8 @@ impl SyntaxEdit {
 #[repr(transparent)]
 pub struct SyntaxAnnotation(NonZeroU32);
 
-impl SyntaxAnnotation {
-    /// Creates a unique syntax annotation to attach data to.
-    pub fn new() -> Self {
+impl Default for SyntaxAnnotation {
+    fn default() -> Self {
         static COUNTER: AtomicU32 = AtomicU32::new(1);
 
         // Only consistency within a thread matters, as SyntaxElements are !Send
@@ -163,12 +162,6 @@ impl SyntaxAnnotation {
     }
 }
 
-impl Default for SyntaxAnnotation {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
 /// Position describing where to insert elements
 #[derive(Debug)]
 pub struct Position {
@@ -411,12 +404,12 @@ mod tests {
         let to_replace = root.syntax().descendants().find_map(ast::BinExpr::cast).unwrap();
 
         let mut editor = SyntaxEditor::new(root.syntax().clone());
-        let make = SyntaxFactory::new();
+        let make = SyntaxFactory::with_mappings();
 
         let name = make::name("var_name");
         let name_ref = make::name_ref("var_name").clone_for_update();
 
-        let placeholder_snippet = SyntaxAnnotation::new();
+        let placeholder_snippet = SyntaxAnnotation::default();
         editor.add_annotation(name.syntax(), placeholder_snippet);
         editor.add_annotation(name_ref.syntax(), placeholder_snippet);
 
@@ -522,7 +515,7 @@ mod tests {
         let second_let = root.syntax().descendants().find_map(ast::LetStmt::cast).unwrap();
 
         let mut editor = SyntaxEditor::new(root.syntax().clone());
-        let make = SyntaxFactory::new();
+        let make = SyntaxFactory::with_mappings();
 
         let new_block_expr = make.block_expr([], Some(ast::Expr::BlockExpr(inner_block.clone())));
 
@@ -574,7 +567,7 @@ mod tests {
         let inner_block = root.clone();
 
         let mut editor = SyntaxEditor::new(root.syntax().clone());
-        let make = SyntaxFactory::new();
+        let make = SyntaxFactory::with_mappings();
 
         let new_block_expr = make.block_expr([], Some(ast::Expr::BlockExpr(inner_block.clone())));
 

crates/syntax/src/syntax_editor/mapping.rs

@@ -20,10 +20,6 @@ pub struct SyntaxMapping {
 }
 
 impl SyntaxMapping {
-    pub fn new() -> Self {
-        Self::default()
-    }
-
     /// Like [`SyntaxMapping::upmap_child`] but for syntax elements.
     pub fn upmap_child_element(
         &self,

crates/test-fixture/src/lib.rs

@@ -139,7 +139,7 @@ impl ChangeFixture {
             let channel = toolchain.as_deref().unwrap_or("stable");
             Version::parse(&format!("1.76.0-{channel}")).unwrap()
         });
-        let mut source_change = FileChange::new();
+        let mut source_change = FileChange::default();
 
         let mut files = Vec::new();
         let mut crate_graph = CrateGraphBuilder::default();

xtask/src/publish/notes.rs

@@ -85,7 +85,7 @@ impl<'a, 'b, R: BufRead> Converter<'a, 'b, R> {
     }
 
     fn process_list(&mut self) -> anyhow::Result<()> {
-        let mut nesting = ListNesting::new();
+        let mut nesting = ListNesting::default();
         while let Some(line) = self.iter.peek() {
             let line = line.as_deref().map_err(|e| anyhow!("{e}"))?;
 
@@ -385,10 +385,6 @@ fn parse_media_block<'a>(line: &'a str, prefix: &str) -> Option<(&'a str, &'a st
 struct ListNesting(Vec<ListMarker>);
 
 impl ListNesting {
-    fn new() -> Self {
-        Self(Vec::<ListMarker>::with_capacity(6))
-    }
-
     fn current(&mut self) -> Option<&ListMarker> {
         self.0.last()
     }
@@ -417,6 +413,12 @@ impl ListNesting {
     }
 }
 
+impl Default for ListNesting {
+    fn default() -> Self {
+        Self(Vec::<ListMarker>::with_capacity(6))
+    }
+}
+
 #[derive(Debug, PartialEq, Eq)]
 enum ListMarker {
     Asterisk(usize),