1 //! `render` module provides utilities for rendering completion suggestions
2 //! into code pieces that will be presented to user.
5 pub(crate) mod function;
6 pub(crate) mod enum_variant;
8 pub(crate) mod pattern;
9 pub(crate) mod type_alias;
10 pub(crate) mod struct_literal;
14 use hir::{AsAssocItem, HasAttrs, HirDisplay};
16 helpers::{item_name, SnippetCap},
17 RootDatabase, SymbolKind,
19 use syntax::{SmolStr, SyntaxKind, TextRange};
22 context::{PathCompletionContext, PathKind},
23 item::{CompletionRelevanceTypeMatch, ImportEdit},
24 render::{enum_variant::render_variant, function::render_fn, macro_::render_macro},
25 CompletionContext, CompletionItem, CompletionItemKind, CompletionRelevance,
27 /// Interface for data and methods required for items rendering.
29 pub(crate) struct RenderContext<'a> {
30 completion: &'a CompletionContext<'a>,
33 impl<'a> RenderContext<'a> {
34 pub(crate) fn new(completion: &'a CompletionContext<'a>) -> RenderContext<'a> {
35 RenderContext { completion }
38 fn snippet_cap(&self) -> Option<SnippetCap> {
39 self.completion.config.snippet_cap
42 fn db(&self) -> &'a RootDatabase {
46 fn source_range(&self) -> TextRange {
47 self.completion.source_range()
50 fn is_deprecated(&self, node: impl HasAttrs) -> bool {
51 let attrs = node.attrs(self.db());
52 attrs.by_key("deprecated").exists() || attrs.by_key("rustc_deprecated").exists()
55 fn is_deprecated_assoc_item(&self, as_assoc_item: impl AsAssocItem) -> bool {
57 let assoc = match as_assoc_item.as_assoc_item(db) {
62 let is_assoc_deprecated = match assoc {
63 hir::AssocItem::Function(it) => self.is_deprecated(it),
64 hir::AssocItem::Const(it) => self.is_deprecated(it),
65 hir::AssocItem::TypeAlias(it) => self.is_deprecated(it),
69 .containing_trait_or_trait_impl(db)
70 .map(|trait_| self.is_deprecated(trait_))
74 fn docs(&self, node: impl HasAttrs) -> Option<hir::Documentation> {
79 pub(crate) fn render_field(
80 ctx: RenderContext<'_>,
81 receiver: Option<hir::Name>,
85 let is_deprecated = ctx.is_deprecated(field);
86 let name = field.name(ctx.db()).to_smol_str();
87 let mut item = CompletionItem::new(
90 receiver.map_or_else(|| name.clone(), |receiver| format!("{}.{}", receiver, name).into()),
92 item.set_relevance(CompletionRelevance {
93 type_match: compute_type_match(ctx.completion, ty),
94 exact_name_match: compute_exact_name_match(ctx.completion, name.as_str()),
95 ..CompletionRelevance::default()
97 item.detail(ty.display(ctx.db()).to_string())
98 .set_documentation(field.docs(ctx.db()))
99 .set_deprecated(is_deprecated)
100 .lookup_by(name.clone());
101 let is_keyword = SyntaxKind::from_keyword(name.as_str()).is_some();
102 if is_keyword && !matches!(name.as_str(), "self" | "crate" | "super" | "Self") {
103 item.insert_text(format!("r#{}", name));
105 if let Some(_ref_match) = compute_ref_match(ctx.completion, ty) {
107 // For now we don't properly calculate the edits for ref match
108 // completions on struct fields, so we've disabled them. See #8058.
113 pub(crate) fn render_tuple_field(
114 ctx: RenderContext<'_>,
115 receiver: Option<hir::Name>,
118 ) -> CompletionItem {
119 let mut item = CompletionItem::new(
122 receiver.map_or_else(|| field.to_string(), |receiver| format!("{}.{}", receiver, field)),
124 item.detail(ty.display(ctx.db()).to_string()).lookup_by(field.to_string());
128 pub(crate) fn render_resolution(
129 ctx: RenderContext<'_>,
130 local_name: hir::Name,
131 resolution: &hir::ScopeDef,
132 ) -> Option<CompletionItem> {
133 render_resolution_(ctx, local_name, None, resolution)
136 pub(crate) fn render_resolution_with_import(
137 ctx: RenderContext<'_>,
138 import_edit: ImportEdit,
139 ) -> Option<CompletionItem> {
140 let resolution = hir::ScopeDef::from(import_edit.import.original_item);
141 let local_name = match resolution {
142 hir::ScopeDef::ModuleDef(hir::ModuleDef::Function(f)) => f.name(ctx.completion.db),
143 hir::ScopeDef::ModuleDef(hir::ModuleDef::Const(c)) => c.name(ctx.completion.db)?,
144 hir::ScopeDef::ModuleDef(hir::ModuleDef::TypeAlias(t)) => t.name(ctx.completion.db),
145 _ => item_name(ctx.db(), import_edit.import.original_item)?,
147 render_resolution_(ctx, local_name, Some(import_edit), &resolution)
150 fn render_resolution_(
151 ctx: RenderContext<'_>,
152 local_name: hir::Name,
153 import_to_add: Option<ImportEdit>,
154 resolution: &hir::ScopeDef,
155 ) -> Option<CompletionItem> {
156 let _p = profile::span("render_resolution");
157 use hir::ModuleDef::*;
159 let kind = match resolution {
160 hir::ScopeDef::ModuleDef(Function(func)) => {
161 return render_fn(ctx, import_to_add, Some(local_name), *func);
163 hir::ScopeDef::ModuleDef(Variant(_)) if ctx.completion.pattern_ctx.is_some() => {
164 CompletionItemKind::SymbolKind(SymbolKind::Variant)
166 hir::ScopeDef::ModuleDef(Variant(var)) => {
167 let item = render_variant(ctx, import_to_add, Some(local_name), *var, None);
170 hir::ScopeDef::MacroDef(mac) => {
171 let item = render_macro(ctx, import_to_add, local_name, *mac);
175 hir::ScopeDef::ModuleDef(Module(..)) => CompletionItemKind::SymbolKind(SymbolKind::Module),
176 hir::ScopeDef::ModuleDef(Adt(adt)) => CompletionItemKind::SymbolKind(match adt {
177 hir::Adt::Struct(_) => SymbolKind::Struct,
178 hir::Adt::Union(_) => SymbolKind::Union,
179 hir::Adt::Enum(_) => SymbolKind::Enum,
181 hir::ScopeDef::ModuleDef(Const(..)) => CompletionItemKind::SymbolKind(SymbolKind::Const),
182 hir::ScopeDef::ModuleDef(Static(..)) => CompletionItemKind::SymbolKind(SymbolKind::Static),
183 hir::ScopeDef::ModuleDef(Trait(..)) => CompletionItemKind::SymbolKind(SymbolKind::Trait),
184 hir::ScopeDef::ModuleDef(TypeAlias(..)) => {
185 CompletionItemKind::SymbolKind(SymbolKind::TypeAlias)
187 hir::ScopeDef::ModuleDef(BuiltinType(..)) => CompletionItemKind::BuiltinType,
188 hir::ScopeDef::GenericParam(param) => CompletionItemKind::SymbolKind(match param {
189 hir::GenericParam::TypeParam(_) => SymbolKind::TypeParam,
190 hir::GenericParam::LifetimeParam(_) => SymbolKind::LifetimeParam,
191 hir::GenericParam::ConstParam(_) => SymbolKind::ConstParam,
193 hir::ScopeDef::Local(..) => CompletionItemKind::SymbolKind(SymbolKind::Local),
194 hir::ScopeDef::Label(..) => CompletionItemKind::SymbolKind(SymbolKind::Label),
195 hir::ScopeDef::AdtSelfType(..) | hir::ScopeDef::ImplSelfType(..) => {
196 CompletionItemKind::SymbolKind(SymbolKind::SelfParam)
198 hir::ScopeDef::Unknown => {
199 let mut item = CompletionItem::new(
200 CompletionItemKind::UnresolvedReference,
202 local_name.to_smol_str(),
204 if let Some(import_to_add) = import_to_add {
205 item.add_import(import_to_add);
207 return Some(item.build());
211 let local_name = local_name.to_smol_str();
212 let mut item = CompletionItem::new(kind, ctx.source_range(), local_name.clone());
213 if let hir::ScopeDef::Local(local) = resolution {
214 let ty = local.ty(ctx.db());
215 if !ty.is_unknown() {
216 item.detail(ty.display(ctx.db()).to_string());
219 item.set_relevance(CompletionRelevance {
220 type_match: compute_type_match(ctx.completion, &ty),
221 exact_name_match: compute_exact_name_match(ctx.completion, &local_name),
223 ..CompletionRelevance::default()
226 if let Some(ref_match) = compute_ref_match(ctx.completion, &ty) {
227 item.ref_match(ref_match);
231 // Add `<>` for generic types
233 ctx.completion.path_context,
234 Some(PathCompletionContext { kind: Some(PathKind::Type), has_type_args: false, .. })
235 ) && ctx.completion.config.add_call_parenthesis
237 if let Some(cap) = ctx.snippet_cap() {
238 let has_non_default_type_params = match resolution {
239 hir::ScopeDef::ModuleDef(Adt(it)) => it.has_non_default_type_params(ctx.db()),
240 hir::ScopeDef::ModuleDef(TypeAlias(it)) => it.has_non_default_type_params(ctx.db()),
243 if has_non_default_type_params {
244 cov_mark::hit!(inserts_angle_brackets_for_generics);
245 item.lookup_by(local_name.clone())
246 .label(SmolStr::from_iter([&local_name, "<…>"]))
247 .insert_snippet(cap, format!("{}<$0>", local_name));
251 item.set_documentation(scope_def_docs(ctx.db(), resolution))
252 .set_deprecated(scope_def_is_deprecated(&ctx, resolution));
254 if let Some(import_to_add) = import_to_add {
255 item.add_import(import_to_add);
260 fn scope_def_docs(db: &RootDatabase, resolution: &hir::ScopeDef) -> Option<hir::Documentation> {
261 use hir::ModuleDef::*;
263 hir::ScopeDef::ModuleDef(Module(it)) => it.docs(db),
264 hir::ScopeDef::ModuleDef(Adt(it)) => it.docs(db),
265 hir::ScopeDef::ModuleDef(Variant(it)) => it.docs(db),
266 hir::ScopeDef::ModuleDef(Const(it)) => it.docs(db),
267 hir::ScopeDef::ModuleDef(Static(it)) => it.docs(db),
268 hir::ScopeDef::ModuleDef(Trait(it)) => it.docs(db),
269 hir::ScopeDef::ModuleDef(TypeAlias(it)) => it.docs(db),
274 fn scope_def_is_deprecated(ctx: &RenderContext<'_>, resolution: &hir::ScopeDef) -> bool {
276 hir::ScopeDef::ModuleDef(it) => ctx.is_deprecated_assoc_item(*it),
277 hir::ScopeDef::MacroDef(it) => ctx.is_deprecated(*it),
278 hir::ScopeDef::GenericParam(it) => ctx.is_deprecated(*it),
279 hir::ScopeDef::AdtSelfType(it) => ctx.is_deprecated(*it),
284 fn compute_type_match(
285 ctx: &CompletionContext,
286 completion_ty: &hir::Type,
287 ) -> Option<CompletionRelevanceTypeMatch> {
288 let expected_type = ctx.expected_type.as_ref()?;
290 // We don't ever consider unit type to be an exact type match, since
291 // nearly always this is not meaningful to the user.
292 if expected_type.is_unit() {
296 if completion_ty == expected_type {
297 Some(CompletionRelevanceTypeMatch::Exact)
298 } else if expected_type.could_unify_with(ctx.db, completion_ty) {
299 Some(CompletionRelevanceTypeMatch::CouldUnify)
305 fn compute_exact_name_match(ctx: &CompletionContext, completion_name: &str) -> bool {
306 ctx.expected_name.as_ref().map_or(false, |name| name.text() == completion_name)
309 fn compute_ref_match(
310 ctx: &CompletionContext,
311 completion_ty: &hir::Type,
312 ) -> Option<hir::Mutability> {
313 let expected_type = ctx.expected_type.as_ref()?;
314 if completion_ty != expected_type {
315 let expected_type_without_ref = expected_type.remove_ref()?;
316 if completion_ty.autoderef(ctx.db).any(|deref_ty| deref_ty == expected_type_without_ref) {
317 cov_mark::hit!(suggest_ref);
318 let mutability = if expected_type.is_mutable_reference() {
321 hir::Mutability::Shared
323 return Some(mutability);
333 use expect_test::{expect, Expect};
334 use ide_db::SymbolKind;
335 use itertools::Itertools;
338 item::CompletionRelevanceTypeMatch,
339 tests::{check_edit, do_completion, get_all_items, TEST_CONFIG},
340 CompletionItem, CompletionItemKind, CompletionRelevance,
344 fn check(ra_fixture: &str, kind: impl Into<CompletionItemKind>, expect: Expect) {
345 let actual = do_completion(ra_fixture, kind.into());
346 expect.assert_debug_eq(&actual);
350 fn check_kinds(ra_fixture: &str, kinds: &[CompletionItemKind], expect: Expect) {
352 kinds.iter().flat_map(|&kind| do_completion(ra_fixture, kind)).collect();
353 expect.assert_debug_eq(&actual);
357 fn check_relevance_for_kinds(ra_fixture: &str, kinds: &[CompletionItemKind], expect: Expect) {
358 let mut actual = get_all_items(TEST_CONFIG, ra_fixture);
359 actual.retain(|it| kinds.contains(&it.kind()));
360 actual.sort_by_key(|it| cmp::Reverse(it.relevance().score()));
361 check_relevance_(actual, expect);
365 fn check_relevance(ra_fixture: &str, expect: Expect) {
366 let mut actual = get_all_items(TEST_CONFIG, ra_fixture);
367 actual.retain(|it| it.kind() != CompletionItemKind::Snippet);
368 actual.retain(|it| it.kind() != CompletionItemKind::Keyword);
369 actual.retain(|it| it.kind() != CompletionItemKind::BuiltinType);
370 actual.sort_by_key(|it| cmp::Reverse(it.relevance().score()));
371 check_relevance_(actual, expect);
375 fn check_relevance_(actual: Vec<CompletionItem>, expect: Expect) {
379 let mut items = vec![];
381 let tag = it.kind().tag();
382 let relevance = display_relevance(it.relevance());
383 items.push(format!("{} {} {}\n", tag, it.label(), relevance));
385 if let Some((mutability, relevance)) = it.ref_match() {
386 let label = format!("&{}{}", mutability.as_keyword_for_ref(), it.label());
387 let relevance = display_relevance(relevance);
389 items.push(format!("{} {} {}\n", tag, label, relevance));
394 .collect::<String>();
396 expect.assert_eq(&actual);
398 fn display_relevance(relevance: CompletionRelevance) -> String {
399 let relevance_factors = vec![
400 (relevance.type_match == Some(CompletionRelevanceTypeMatch::Exact), "type"),
402 relevance.type_match == Some(CompletionRelevanceTypeMatch::CouldUnify),
405 (relevance.exact_name_match, "name"),
406 (relevance.is_local, "local"),
407 (relevance.exact_postfix_snippet_match, "snippet"),
410 .filter_map(|(cond, desc)| if cond { Some(desc) } else { None })
413 format!("[{}]", relevance_factors)
418 fn enum_detail_includes_record_fields() {
421 enum Foo { Foo { x: i32, y: i32 } }
423 fn main() { Foo::Fo$0 }
430 source_range: 54..56,
436 detail: "{x: i32, y: i32}",
444 fn enum_detail_doesnt_include_tuple_fields() {
447 enum Foo { Foo (i32, i32) }
449 fn main() { Foo::Fo$0 }
456 source_range: 46..48,
463 detail: "(i32, i32)",
464 trigger_call_info: true,
472 fn fn_detail_includes_args_and_return_type() {
475 fn foo<T>(a: u32, b: u32, t: T) -> (u32, T) { (a, t) }
479 SymbolKind::Function,
484 source_range: 68..70,
486 insert: "foo(${1:a}, ${2:b}, ${3:t})$0",
491 detail: "fn(u32, u32, T) -> (u32, T)",
492 trigger_call_info: true,
496 source_range: 68..70,
511 fn enum_detail_just_parentheses_for_unit() {
516 fn main() { Foo::Fo$0 }
523 source_range: 35..37,
537 fn lookup_enums_by_two_qualifiers() {
541 pub enum Spam { Foo, Bar(i32) }
543 fn main() { let _: m::Spam = S$0 }
546 CompletionItemKind::SymbolKind(SymbolKind::Function),
547 CompletionItemKind::SymbolKind(SymbolKind::Module),
548 CompletionItemKind::SymbolKind(SymbolKind::Variant),
554 source_range: 75..76,
565 source_range: 75..76,
573 label: "Spam::Bar(…)",
574 source_range: 75..76,
576 insert: "Spam::Bar($0)",
582 relevance: CompletionRelevance {
583 exact_name_match: false,
588 exact_postfix_snippet_match: false,
590 trigger_call_info: true,
593 label: "m::Spam::Foo",
594 source_range: 75..76,
596 insert: "m::Spam::Foo",
602 relevance: CompletionRelevance {
603 exact_name_match: false,
608 exact_postfix_snippet_match: false,
617 fn sets_deprecated_flag_in_items() {
621 fn something_deprecated() {}
622 #[rustc_deprecated(since = "1.0.0")]
623 fn something_else_deprecated() {}
627 SymbolKind::Function,
632 source_range: 127..130,
642 label: "something_deprecated()",
643 source_range: 127..130,
645 insert: "something_deprecated()$0",
649 lookup: "something_deprecated",
654 label: "something_else_deprecated()",
655 source_range: 127..130,
657 insert: "something_else_deprecated()$0",
661 lookup: "something_else_deprecated",
671 struct A { #[deprecated] the_field: u32 }
672 fn foo() { A { the$0 } }
679 source_range: 57..60,
687 relevance: CompletionRelevance {
688 exact_name_match: false,
693 exact_postfix_snippet_match: false,
711 fn bar(self) { self.$0 }
713 &[CompletionItemKind::Method, CompletionItemKind::SymbolKind(SymbolKind::Field)],
718 source_range: 94..94,
724 documentation: Documentation(
730 source_range: 94..94,
737 documentation: Documentation(
760 CompletionItemKind::SymbolKind(SymbolKind::Module),
761 CompletionItemKind::SymbolKind(SymbolKind::Variant),
762 CompletionItemKind::SymbolKind(SymbolKind::Enum),
768 source_range: 10..12,
774 documentation: Documentation(
780 source_range: 10..12,
787 documentation: Documentation(
793 source_range: 10..12,
799 documentation: Documentation(
809 fn dont_render_attrs() {
815 fn the_method(&self) { }
817 fn foo(s: S) { s.$0 }
819 CompletionItemKind::Method,
823 label: "the_method()",
824 source_range: 81..81,
826 insert: "the_method()$0",
828 lookup: "the_method",
837 fn no_call_parens_if_fn_ptr_needed() {
838 cov_mark::check!(no_call_parens_if_fn_ptr_needed);
842 fn foo(foo: u8, bar: u8) {}
843 struct ManualVtable { f: fn(u8, u8) }
845 fn main() -> ManualVtable {
846 ManualVtable { f: f$0 }
850 fn foo(foo: u8, bar: u8) {}
851 struct ManualVtable { f: fn(u8, u8) }
853 fn main() -> ManualVtable {
854 ManualVtable { f: foo }
861 struct RawIdentTable { r#type: u32 }
863 fn main() -> RawIdentTable {
864 RawIdentTable { t$0: 42 }
868 struct RawIdentTable { r#type: u32 }
870 fn main() -> RawIdentTable {
871 RawIdentTable { r#type: 42 }
878 fn no_parens_in_use_item() {
879 cov_mark::check!(no_parens_in_use_item);
883 mod m { pub fn foo() {} }
887 mod m { pub fn foo() {} }
894 fn no_parens_in_call() {
910 impl Foo { fn foo(&self){} }
911 fn f(foo: &Foo) { foo.f$0(); }
915 impl Foo { fn foo(&self){} }
916 fn f(foo: &Foo) { foo.foo(); }
922 fn inserts_angle_brackets_for_generics() {
923 cov_mark::check!(inserts_angle_brackets_for_generics);
949 struct Vec<T = i128> {}
953 struct Vec<T = i128> {}
961 fn foo(xs: Ve$0<i128>)
965 fn foo(xs: Vec<i128>)
971 fn active_param_relevance() {
974 struct S { foo: i64, bar: u32, baz: u32 }
975 fn test(bar: u32) { }
976 fn foo(s: S) { test(s.$0) }
987 fn record_field_relevances() {
990 struct A { foo: i64, bar: u32, baz: u32 }
991 struct B { x: (), y: f32, bar: u32 }
992 fn foo(a: A) { B { bar: a.$0 }; }
1003 fn record_field_and_call_relevances() {
1006 struct A { foo: i64, bar: u32, baz: u32 }
1007 struct B { x: (), y: f32, bar: u32 }
1009 fn foo(a: A) { B { bar: f(a.$0) }; }
1019 struct A { foo: i64, bar: u32, baz: u32 }
1020 struct B { x: (), y: f32, bar: u32 }
1022 fn foo(a: A) { f(B { bar: a.$0 }); }
1033 fn prioritize_exact_ref_match() {
1036 struct WorldSnapshot { _f: () };
1037 fn go(world: &WorldSnapshot) { go(w$0) }
1040 lc world [type+name+local]
1048 fn too_many_arguments() {
1049 cov_mark::check!(too_many_arguments);
1053 fn f(foo: &Foo) { f(foo, w$0) }
1064 fn score_fn_type_and_name_match() {
1067 struct A { bar: u8 }
1068 fn baz() -> u8 { 0 }
1069 fn bar() -> u8 { 0 }
1070 fn f() { A { bar: b$0 }; }
1073 fn bar() [type+name]
1082 fn score_method_type_and_name_match() {
1088 fn aaa(&self) -> u32 { 0 }
1089 fn bbb(&self) -> u32 { 0 }
1090 fn ccc(&self) -> u64 { 0 }
1097 me aaa() [type+name]
1105 fn score_method_name_match_only() {
1111 fn aaa(&self) -> u64 { 0 }
1124 fn suggest_ref_mut() {
1125 cov_mark::check!(suggest_ref);
1129 fn foo(s: &mut S) {}
1137 lc &mut s [type+name+local]
1146 fn foo(s: &mut S) {}
1153 lc s [type+name+local]
1162 fn suggest_deref() {
1169 impl core::ops::Deref for T {
1172 fn deref(&self) -> &Self::Target {
1201 fn suggest_deref_mut() {
1204 //- minicore: deref_mut
1208 impl core::ops::Deref for T {
1211 fn deref(&self) -> &Self::Target {
1216 impl core::ops::DerefMut for T {
1217 fn deref_mut(&mut self) -> &mut Self::Target {
1222 fn foo(s: &mut S) {}
1234 lc &mut t [type+local]
1306 fn suggest_deref_fn_ret() {
1313 impl core::ops::Deref for T {
1316 fn deref(&self) -> &Self::Target {
1342 fn struct_field_method_ref() {
1345 struct Foo { bar: u32 }
1346 impl Foo { fn baz(&self) -> u32 { 0 } }
1348 fn foo(f: Foo) { let _: &u32 = f.b$0 }
1350 &[CompletionItemKind::Method, CompletionItemKind::SymbolKind(SymbolKind::Field)],
1352 // Ideally we'd also suggest &f.bar and &f.baz() as exact
1353 // type matches. See #8058.
1358 source_range: 98..99,
1363 detail: "fn(&self) -> u32",
1367 source_range: 98..99,
1384 enum Foo<T> { A(T), B }
1385 // bar() should not be an exact type match
1386 // because the generic parameters are different
1387 fn bar() -> Foo<u8> { Foo::B }
1388 // FIXME baz() should be an exact type match
1389 // because the types could unify, but it currently
1390 // is not. This is due to the T here being
1391 // TyKind::Placeholder rather than TyKind::Missing.
1392 fn baz<T>() -> Foo<T> { Foo::B }
1394 let foo: Foo<u32> = Foo::B;
1395 let _: Foo<u32> = f$0;
1400 ev Foo::A(…) [type_could_unify]
1401 ev Foo::B [type_could_unify]
1411 fn postfix_completion_relevance() {
1412 check_relevance_for_kinds(
1417 fn not(self) -> Self::Output;
1422 fn not(self) -> bool { if self { false } else { true }}
1427 let _: bool = (9 > 2).not$0;
1430 &[CompletionItemKind::Snippet, CompletionItemKind::Method],
1433 me not() (use ops::Not) [type_could_unify]