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;
14 AsAssocItem, Documentation, HasAttrs, HirDisplay, ModuleDef, Mutability, ScopeDef, Type,
17 helpers::{item_name, SnippetCap},
18 RootDatabase, SymbolKind,
20 use syntax::TextRange;
23 item::{CompletionRelevanceTypeMatch, ImportEdit},
24 CompletionContext, CompletionItem, CompletionItemKind, CompletionKind, CompletionRelevance,
27 use crate::render::{enum_variant::render_variant, function::render_fn, macro_::render_macro};
29 pub(crate) fn render_field<'a>(
30 ctx: RenderContext<'a>,
34 Render::new(ctx).add_field(field, ty)
37 pub(crate) fn render_tuple_field<'a>(
38 ctx: RenderContext<'a>,
42 Render::new(ctx).add_tuple_field(field, ty)
45 pub(crate) fn render_resolution<'a>(
46 ctx: RenderContext<'a>,
48 resolution: &ScopeDef,
49 ) -> Option<CompletionItem> {
50 Render::new(ctx).render_resolution(local_name, None, resolution)
53 pub(crate) fn render_resolution_with_import<'a>(
54 ctx: RenderContext<'a>,
55 import_edit: ImportEdit,
56 ) -> Option<CompletionItem> {
57 let resolution = ScopeDef::from(import_edit.import.original_item);
58 let local_name = match resolution {
59 ScopeDef::ModuleDef(ModuleDef::Function(f)) => f.name(ctx.completion.db).to_string(),
60 ScopeDef::ModuleDef(ModuleDef::Const(c)) => c.name(ctx.completion.db)?.to_string(),
61 ScopeDef::ModuleDef(ModuleDef::TypeAlias(t)) => t.name(ctx.completion.db).to_string(),
62 _ => item_name(ctx.db(), import_edit.import.original_item)?.to_string(),
64 Render::new(ctx).render_resolution(local_name, Some(import_edit), &resolution).map(
66 item.completion_kind = CompletionKind::Magic;
72 /// Interface for data and methods required for items rendering.
74 pub(crate) struct RenderContext<'a> {
75 completion: &'a CompletionContext<'a>,
78 impl<'a> RenderContext<'a> {
79 pub(crate) fn new(completion: &'a CompletionContext<'a>) -> RenderContext<'a> {
80 RenderContext { completion }
83 fn snippet_cap(&self) -> Option<SnippetCap> {
84 self.completion.config.snippet_cap
87 fn db(&self) -> &'a RootDatabase {
91 fn source_range(&self) -> TextRange {
92 self.completion.source_range()
95 fn is_deprecated(&self, node: impl HasAttrs) -> bool {
96 let attrs = node.attrs(self.db());
97 attrs.by_key("deprecated").exists() || attrs.by_key("rustc_deprecated").exists()
100 fn is_deprecated_assoc_item(&self, as_assoc_item: impl AsAssocItem) -> bool {
102 let assoc = match as_assoc_item.as_assoc_item(db) {
103 Some(assoc) => assoc,
104 None => return false,
107 let is_assoc_deprecated = match assoc {
108 hir::AssocItem::Function(it) => self.is_deprecated(it),
109 hir::AssocItem::Const(it) => self.is_deprecated(it),
110 hir::AssocItem::TypeAlias(it) => self.is_deprecated(it),
113 || assoc.containing_trait(db).map(|trait_| self.is_deprecated(trait_)).unwrap_or(false)
116 fn docs(&self, node: impl HasAttrs) -> Option<Documentation> {
121 /// Generic renderer for completion items.
124 ctx: RenderContext<'a>,
127 impl<'a> Render<'a> {
128 fn new(ctx: RenderContext<'a>) -> Render<'a> {
132 fn add_field(&mut self, field: hir::Field, ty: &Type) -> CompletionItem {
133 let is_deprecated = self.ctx.is_deprecated(field);
134 let name = field.name(self.ctx.db());
135 let mut item = CompletionItem::new(
136 CompletionKind::Reference,
137 self.ctx.source_range(),
140 item.kind(SymbolKind::Field)
141 .detail(ty.display(self.ctx.db()).to_string())
142 .set_documentation(field.docs(self.ctx.db()))
143 .set_deprecated(is_deprecated);
145 item.set_relevance(CompletionRelevance {
146 type_match: compute_type_match(self.ctx.completion, ty),
147 exact_name_match: compute_exact_name_match(self.ctx.completion, name.to_string()),
148 ..CompletionRelevance::default()
151 if let Some(_ref_match) = compute_ref_match(self.ctx.completion, ty) {
153 // For now we don't properly calculate the edits for ref match
154 // completions on struct fields, so we've disabled them. See #8058.
160 fn add_tuple_field(&mut self, field: usize, ty: &Type) -> CompletionItem {
161 let mut item = CompletionItem::new(
162 CompletionKind::Reference,
163 self.ctx.source_range(),
167 item.kind(SymbolKind::Field).detail(ty.display(self.ctx.db()).to_string());
172 fn render_resolution(
175 import_to_add: Option<ImportEdit>,
176 resolution: &ScopeDef,
177 ) -> Option<CompletionItem> {
178 let _p = profile::span("render_resolution");
179 use hir::ModuleDef::*;
181 let completion_kind = match resolution {
182 ScopeDef::ModuleDef(BuiltinType(..)) => CompletionKind::BuiltinType,
183 _ => CompletionKind::Reference,
186 let kind = match resolution {
187 ScopeDef::ModuleDef(Function(func)) => {
188 return render_fn(self.ctx, import_to_add, Some(local_name), *func);
190 ScopeDef::ModuleDef(Variant(_)) if self.ctx.completion.is_pat_or_const.is_some() => {
191 CompletionItemKind::SymbolKind(SymbolKind::Variant)
193 ScopeDef::ModuleDef(Variant(var)) => {
194 let item = render_variant(self.ctx, import_to_add, Some(local_name), *var, None);
197 ScopeDef::MacroDef(mac) => {
198 let item = render_macro(self.ctx, import_to_add, local_name, *mac);
202 ScopeDef::ModuleDef(Module(..)) => CompletionItemKind::SymbolKind(SymbolKind::Module),
203 ScopeDef::ModuleDef(Adt(adt)) => CompletionItemKind::SymbolKind(match adt {
204 hir::Adt::Struct(_) => SymbolKind::Struct,
205 hir::Adt::Union(_) => SymbolKind::Union,
206 hir::Adt::Enum(_) => SymbolKind::Enum,
208 ScopeDef::ModuleDef(Const(..)) => CompletionItemKind::SymbolKind(SymbolKind::Const),
209 ScopeDef::ModuleDef(Static(..)) => CompletionItemKind::SymbolKind(SymbolKind::Static),
210 ScopeDef::ModuleDef(Trait(..)) => CompletionItemKind::SymbolKind(SymbolKind::Trait),
211 ScopeDef::ModuleDef(TypeAlias(..)) => {
212 CompletionItemKind::SymbolKind(SymbolKind::TypeAlias)
214 ScopeDef::ModuleDef(BuiltinType(..)) => CompletionItemKind::BuiltinType,
215 ScopeDef::GenericParam(param) => CompletionItemKind::SymbolKind(match param {
216 hir::GenericParam::TypeParam(_) => SymbolKind::TypeParam,
217 hir::GenericParam::LifetimeParam(_) => SymbolKind::LifetimeParam,
218 hir::GenericParam::ConstParam(_) => SymbolKind::ConstParam,
220 ScopeDef::Local(..) => CompletionItemKind::SymbolKind(SymbolKind::Local),
221 ScopeDef::Label(..) => CompletionItemKind::SymbolKind(SymbolKind::Label),
222 ScopeDef::AdtSelfType(..) | ScopeDef::ImplSelfType(..) => {
223 CompletionItemKind::SymbolKind(SymbolKind::SelfParam)
225 ScopeDef::Unknown => {
226 let mut item = CompletionItem::new(
227 CompletionKind::Reference,
228 self.ctx.source_range(),
231 item.kind(CompletionItemKind::UnresolvedReference).add_import(import_to_add);
232 return Some(item.build());
237 CompletionItem::new(completion_kind, self.ctx.source_range(), local_name.clone());
238 if let ScopeDef::Local(local) = resolution {
239 let ty = local.ty(self.ctx.db());
240 if !ty.is_unknown() {
241 item.detail(ty.display(self.ctx.db()).to_string());
244 item.set_relevance(CompletionRelevance {
245 type_match: compute_type_match(self.ctx.completion, &ty),
246 exact_name_match: compute_exact_name_match(self.ctx.completion, &local_name),
248 ..CompletionRelevance::default()
251 if let Some(ref_match) = compute_ref_match(self.ctx.completion, &ty) {
252 item.ref_match(ref_match);
256 // Add `<>` for generic types
257 if self.ctx.completion.is_path_type
258 && !self.ctx.completion.has_type_args
259 && self.ctx.completion.config.add_call_parenthesis
261 if let Some(cap) = self.ctx.snippet_cap() {
262 let has_non_default_type_params = match resolution {
263 ScopeDef::ModuleDef(Adt(it)) => it.has_non_default_type_params(self.ctx.db()),
264 ScopeDef::ModuleDef(TypeAlias(it)) => {
265 it.has_non_default_type_params(self.ctx.db())
269 if has_non_default_type_params {
270 cov_mark::hit!(inserts_angle_brackets_for_generics);
271 item.lookup_by(local_name.clone())
272 .label(format!("{}<…>", local_name))
273 .insert_snippet(cap, format!("{}<$0>", local_name));
278 .add_import(import_to_add)
279 .set_documentation(self.docs(resolution))
280 .set_deprecated(self.is_deprecated(resolution));
284 fn docs(&self, resolution: &ScopeDef) -> Option<Documentation> {
285 use hir::ModuleDef::*;
287 ScopeDef::ModuleDef(Module(it)) => it.docs(self.ctx.db()),
288 ScopeDef::ModuleDef(Adt(it)) => it.docs(self.ctx.db()),
289 ScopeDef::ModuleDef(Variant(it)) => it.docs(self.ctx.db()),
290 ScopeDef::ModuleDef(Const(it)) => it.docs(self.ctx.db()),
291 ScopeDef::ModuleDef(Static(it)) => it.docs(self.ctx.db()),
292 ScopeDef::ModuleDef(Trait(it)) => it.docs(self.ctx.db()),
293 ScopeDef::ModuleDef(TypeAlias(it)) => it.docs(self.ctx.db()),
298 fn is_deprecated(&self, resolution: &ScopeDef) -> bool {
300 ScopeDef::ModuleDef(it) => self.ctx.is_deprecated_assoc_item(*it),
301 ScopeDef::MacroDef(it) => self.ctx.is_deprecated(*it),
302 ScopeDef::GenericParam(it) => self.ctx.is_deprecated(*it),
303 ScopeDef::AdtSelfType(it) => self.ctx.is_deprecated(*it),
309 fn compute_type_match(
310 ctx: &CompletionContext,
311 completion_ty: &hir::Type,
312 ) -> Option<CompletionRelevanceTypeMatch> {
313 let expected_type = ctx.expected_type.as_ref()?;
315 // We don't ever consider unit type to be an exact type match, since
316 // nearly always this is not meaningful to the user.
317 if expected_type.is_unit() {
321 if completion_ty == expected_type {
322 Some(CompletionRelevanceTypeMatch::Exact)
323 } else if expected_type.could_unify_with(ctx.db, completion_ty) {
324 Some(CompletionRelevanceTypeMatch::CouldUnify)
330 fn compute_exact_name_match(ctx: &CompletionContext, completion_name: impl Into<String>) -> bool {
331 let completion_name = completion_name.into();
332 ctx.expected_name.as_ref().map_or(false, |name| name.text() == completion_name)
335 fn compute_ref_match(ctx: &CompletionContext, completion_ty: &hir::Type) -> Option<Mutability> {
336 let expected_type = ctx.expected_type.as_ref()?;
337 if completion_ty != expected_type {
338 let expected_type_without_ref = expected_type.remove_ref()?;
339 if completion_ty.autoderef(ctx.db).any(|deref_ty| deref_ty == expected_type_without_ref) {
340 cov_mark::hit!(suggest_ref);
341 let mutability = if expected_type.is_mutable_reference() {
346 return Some(mutability);
354 use expect_test::{expect, Expect};
355 use itertools::Itertools;
358 item::CompletionRelevanceTypeMatch,
359 test_utils::{check_edit, do_completion, get_all_items, TEST_CONFIG},
360 CompletionKind, CompletionRelevance,
363 fn check(ra_fixture: &str, expect: Expect) {
364 let actual = do_completion(ra_fixture, CompletionKind::Reference);
365 expect.assert_debug_eq(&actual);
368 fn check_relevance(ra_fixture: &str, expect: Expect) {
369 fn display_relevance(relevance: CompletionRelevance) -> String {
370 let relevance_factors = vec![
371 (relevance.type_match == Some(CompletionRelevanceTypeMatch::Exact), "type"),
373 relevance.type_match == Some(CompletionRelevanceTypeMatch::CouldUnify),
376 (relevance.exact_name_match, "name"),
377 (relevance.is_local, "local"),
380 .filter_map(|(cond, desc)| if cond { Some(desc) } else { None })
383 format!("[{}]", relevance_factors)
386 let actual = get_all_items(TEST_CONFIG, ra_fixture)
388 .filter(|it| it.completion_kind == CompletionKind::Reference)
390 let mut items = vec![];
392 let tag = it.kind().unwrap().tag();
393 let relevance = display_relevance(it.relevance());
394 items.push(format!("{} {} {}\n", tag, it.label(), relevance));
396 if let Some((mutability, relevance)) = it.ref_match() {
397 let label = format!("&{}{}", mutability.as_keyword_for_ref(), it.label());
398 let relevance = display_relevance(relevance);
400 items.push(format!("{} {} {}\n", tag, label, relevance));
405 .collect::<String>();
407 expect.assert_eq(&actual);
411 fn enum_detail_includes_record_fields() {
414 enum Foo { Foo { x: i32, y: i32 } }
416 fn main() { Foo::Fo$0 }
422 source_range: 54..56,
428 detail: "{ x: i32, y: i32 }",
436 fn enum_detail_doesnt_include_tuple_fields() {
439 enum Foo { Foo (i32, i32) }
441 fn main() { Foo::Fo$0 }
447 source_range: 46..48,
454 detail: "(i32, i32)",
455 trigger_call_info: true,
463 fn fn_detail_includes_args_and_return_type() {
466 fn foo<T>(a: u32, b: u32, t: T) -> (u32, T) { (a, t) }
474 source_range: 68..70,
476 insert: "foo(${1:a}, ${2:b}, ${3:t})$0",
481 detail: "fn(u32, u32, T) -> (u32, T)",
482 trigger_call_info: true,
486 source_range: 68..70,
501 fn enum_detail_just_parentheses_for_unit() {
506 fn main() { Foo::Fo$0 }
512 source_range: 35..37,
526 fn lookup_enums_by_two_qualifiers() {
530 pub enum Spam { Foo, Bar(i32) }
532 fn main() { let _: m::Spam = S$0 }
537 label: "Spam::Bar(…)",
538 source_range: 75..76,
540 insert: "Spam::Bar($0)",
546 relevance: CompletionRelevance {
547 exact_name_match: false,
553 trigger_call_info: true,
557 source_range: 75..76,
565 label: "m::Spam::Foo",
566 source_range: 75..76,
568 insert: "m::Spam::Foo",
574 relevance: CompletionRelevance {
575 exact_name_match: false,
584 source_range: 75..76,
599 fn sets_deprecated_flag_in_items() {
603 fn something_deprecated() {}
604 #[rustc_deprecated(since = "1.0.0")]
605 fn something_else_deprecated() {}
613 source_range: 127..130,
623 label: "something_deprecated()",
624 source_range: 127..130,
626 insert: "something_deprecated()$0",
630 lookup: "something_deprecated",
635 label: "something_else_deprecated()",
636 source_range: 127..130,
638 insert: "something_else_deprecated()$0",
642 lookup: "something_else_deprecated",
652 struct A { #[deprecated] the_field: u32 }
653 fn foo() { A { the$0 } }
659 source_range: 57..60,
667 relevance: CompletionRelevance {
668 exact_name_match: false,
690 fn bar(self) { self.$0 }
696 source_range: 94..94,
702 documentation: Documentation(
708 source_range: 94..94,
715 documentation: Documentation(
741 source_range: 10..12,
747 documentation: Documentation(
753 source_range: 10..12,
760 documentation: Documentation(
766 source_range: 10..12,
772 documentation: Documentation(
782 fn dont_render_attrs() {
788 fn the_method(&self) { }
790 fn foo(s: S) { s.$0 }
795 label: "the_method()",
796 source_range: 81..81,
798 insert: "the_method()$0",
800 lookup: "the_method",
809 fn no_call_parens_if_fn_ptr_needed() {
810 cov_mark::check!(no_call_parens_if_fn_ptr_needed);
814 fn foo(foo: u8, bar: u8) {}
815 struct ManualVtable { f: fn(u8, u8) }
817 fn main() -> ManualVtable {
818 ManualVtable { f: f$0 }
822 fn foo(foo: u8, bar: u8) {}
823 struct ManualVtable { f: fn(u8, u8) }
825 fn main() -> ManualVtable {
826 ManualVtable { f: foo }
833 fn no_parens_in_use_item() {
834 cov_mark::check!(no_parens_in_use_item);
838 mod m { pub fn foo() {} }
842 mod m { pub fn foo() {} }
849 fn no_parens_in_call() {
865 impl Foo { fn foo(&self){} }
866 fn f(foo: &Foo) { foo.f$0(); }
870 impl Foo { fn foo(&self){} }
871 fn f(foo: &Foo) { foo.foo(); }
877 fn inserts_angle_brackets_for_generics() {
878 cov_mark::check!(inserts_angle_brackets_for_generics);
904 struct Vec<T = i128> {}
908 struct Vec<T = i128> {}
916 fn foo(xs: Ve$0<i128>)
920 fn foo(xs: Vec<i128>)
926 fn active_param_relevance() {
929 struct S { foo: i64, bar: u32, baz: u32 }
930 fn test(bar: u32) { }
931 fn foo(s: S) { test(s.$0) }
942 fn record_field_relevances() {
945 struct A { foo: i64, bar: u32, baz: u32 }
946 struct B { x: (), y: f32, bar: u32 }
947 fn foo(a: A) { B { bar: a.$0 }; }
958 fn record_field_and_call_relevances() {
961 struct A { foo: i64, bar: u32, baz: u32 }
962 struct B { x: (), y: f32, bar: u32 }
964 fn foo(a: A) { B { bar: f(a.$0) }; }
974 struct A { foo: i64, bar: u32, baz: u32 }
975 struct B { x: (), y: f32, bar: u32 }
977 fn foo(a: A) { f(B { bar: a.$0 }); }
988 fn prioritize_exact_ref_match() {
991 struct WorldSnapshot { _f: () };
992 fn go(world: &WorldSnapshot) { go(w$0) }
995 lc world [type+name+local]
1003 fn too_many_arguments() {
1007 fn f(foo: &Foo) { f(foo, w$0) }
1018 fn score_fn_type_and_name_match() {
1021 struct A { bar: u8 }
1022 fn baz() -> u8 { 0 }
1023 fn bar() -> u8 { 0 }
1024 fn f() { A { bar: b$0 }; }
1029 fn bar() [type+name]
1036 fn score_method_type_and_name_match() {
1042 fn aaa(&self) -> u32 { 0 }
1043 fn bbb(&self) -> u32 { 0 }
1044 fn ccc(&self) -> u64 { 0 }
1051 me aaa() [type+name]
1059 fn score_method_name_match_only() {
1065 fn aaa(&self) -> u64 { 0 }
1078 fn suggest_ref_mut() {
1079 cov_mark::check!(suggest_ref);
1083 fn foo(s: &mut S) {}
1093 source_range: 70..70,
1102 source_range: 70..70,
1104 insert: "foo(${1:&mut s})$0",
1109 detail: "fn(&mut S)",
1110 trigger_call_info: true,
1114 source_range: 70..70,
1125 source_range: 70..70,
1132 relevance: CompletionRelevance {
1133 exact_name_match: true,
1145 fn suggest_deref() {
1151 fn deref(&self) -> &Self::Target;
1160 fn deref(&self) -> &Self::Target {
1188 fn suggest_deref_mut() {
1194 fn deref(&self) -> &Self::Target;
1197 #[lang = "deref_mut"]
1198 pub trait DerefMut: Deref {
1199 fn deref_mut(&mut self) -> &mut Self::Target;
1208 fn deref(&self) -> &Self::Target {
1213 impl DerefMut for T {
1214 fn deref_mut(&mut self) -> &mut Self::Target {
1219 fn foo(s: &mut S) {}
1231 lc &mut t [type+local]
1303 fn suggest_deref_fn_ret() {
1309 fn deref(&self) -> &Self::Target;
1318 fn deref(&self) -> &Self::Target {
1343 fn struct_field_method_ref() {
1346 struct Foo { bar: u32 }
1347 impl Foo { fn baz(&self) -> u32 { 0 } }
1349 fn foo(f: Foo) { let _: &u32 = f.b$0 }
1352 // Ideally we'd also suggest &f.bar and &f.baz() as exact
1353 // type matches. See #8058.
1358 source_range: 98..99,
1368 source_range: 98..99,
1373 detail: "fn(&self) -> u32",
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;
1399 ev Foo::A(…) [type_could_unify]
1400 ev Foo::B [type_could_unify]