1 //! Patterns telling us certain facts about current syntax element, they are used in completion context
4 use ide_db::RootDatabase;
6 algo::non_trivia_sibling,
7 ast::{self, ArgListOwner, LoopBodyOwner},
8 match_ast, AstNode, Direction, SyntaxElement,
10 SyntaxNode, SyntaxToken, TextRange, TextSize, T,
14 use crate::tests::{check_pattern_is_applicable, check_pattern_is_not_applicable};
16 /// Immediate previous node to what we are completing.
17 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
18 pub(crate) enum ImmediatePrevSibling {
26 /// Direct parent "thing" of what we are currently completing.
27 #[derive(Clone, Debug, PartialEq, Eq)]
28 pub(crate) enum ImmediateLocation {
43 ModDeclaration(ast::Module),
44 Visibility(ast::Visibility),
45 // Original file ast node
47 receiver: Option<ast::Expr>,
50 // Original file ast node
52 receiver: Option<ast::Expr>,
53 receiver_is_ambiguous_float_literal: bool,
55 // Original file ast node
56 // Only set from a type arg
57 GenericArgList(ast::GenericArgList),
58 // Original file ast node
59 /// The record expr of the field name we are completing
60 RecordExpr(ast::RecordExpr),
61 // Original file ast node
62 /// The record pat of the field name we are completing
63 RecordPat(ast::RecordPat),
66 pub(crate) fn determine_prev_sibling(name_like: &ast::NameLike) -> Option<ImmediatePrevSibling> {
67 let node = match name_like {
68 ast::NameLike::NameRef(name_ref) => maximize_name_ref(name_ref),
69 ast::NameLike::Name(n) => n.syntax().clone(),
70 ast::NameLike::Lifetime(lt) => lt.syntax().clone(),
72 let node = match node.parent().and_then(ast::MacroCall::cast) {
73 // When a path is being typed after the name of a trait/type of an impl it is being
74 // parsed as a macro, so when the trait/impl has a block following it an we are between the
75 // name and block the macro will attach the block to itself so maximizing fails to take
77 // FIXME path expr and statement have a similar problem with attrs
79 if call.excl_token().is_none()
80 && call.token_tree().map_or(false, |t| t.l_curly_token().is_some())
81 && call.semicolon_token().is_none() =>
87 let prev_sibling = non_trivia_sibling(node.into(), Direction::Prev)?.into_node()?;
88 if prev_sibling.kind() == ERROR {
89 let prev_sibling = prev_sibling.first_child()?;
90 let res = match_ast! {
92 // vis followed by random ident will always error the parser
93 ast::Visibility(_it) => ImmediatePrevSibling::Visibility,
99 let res = match_ast! {
101 ast::ExprStmt(it) => {
102 let node = it.expr().filter(|_| it.semicolon_token().is_none())?.syntax().clone();
105 ast::IfExpr(_it) => ImmediatePrevSibling::IfExpr,
110 ast::Trait(it) => if it.assoc_item_list().is_none() {
111 ImmediatePrevSibling::TraitDefName
115 ast::Impl(it) => if it.assoc_item_list().is_none()
116 && (it.for_token().is_none() || it.self_ty().is_some()) {
117 ImmediatePrevSibling::ImplDefType
121 ast::Attr(_it) => ImmediatePrevSibling::Attribute,
128 pub(crate) fn determine_location(
129 sema: &Semantics<RootDatabase>,
130 original_file: &SyntaxNode,
132 name_like: &ast::NameLike,
133 ) -> Option<ImmediateLocation> {
134 let node = match name_like {
135 ast::NameLike::NameRef(name_ref) => {
136 if ast::RecordExprField::for_field_name(name_ref).is_some() {
138 .find_node_at_offset_with_macros(original_file, offset)
139 .map(ImmediateLocation::RecordExpr);
141 if ast::RecordPatField::for_field_name_ref(name_ref).is_some() {
143 .find_node_at_offset_with_macros(original_file, offset)
144 .map(ImmediateLocation::RecordPat);
146 maximize_name_ref(name_ref)
148 ast::NameLike::Name(name) => {
149 if ast::RecordPatField::for_field_name(name).is_some() {
151 .find_node_at_offset_with_macros(original_file, offset)
152 .map(ImmediateLocation::RecordPat);
154 name.syntax().clone()
156 ast::NameLike::Lifetime(lt) => lt.syntax().clone(),
161 ast::TypeBoundList(_it) => return Some(ImmediateLocation::TypeBound),
166 let parent = match node.parent() {
167 Some(parent) => match ast::MacroCall::cast(parent.clone()) {
168 // When a path is being typed in an (Assoc)ItemList the parser will always emit a macro_call.
169 // This is usually fine as the node expansion code above already accounts for that with
170 // the ancestors call, but there is one exception to this which is that when an attribute
171 // precedes it the code above will not walk the Path to the parent MacroCall as their ranges differ.
172 // FIXME path expr and statement have a similar problem
174 if call.excl_token().is_none()
175 && call.token_tree().is_none()
176 && call.semicolon_token().is_none() =>
178 call.syntax().parent()?
184 return match node.kind() {
185 MACRO_ITEMS | SOURCE_FILE => Some(ImmediateLocation::ItemList),
190 let res = match_ast! {
192 ast::IdentPat(_it) => ImmediateLocation::IdentPat,
193 ast::Use(_it) => ImmediateLocation::Use,
194 ast::UseTree(_it) => ImmediateLocation::UseTree,
195 ast::UseTreeList(_it) => ImmediateLocation::UseTree,
196 ast::BlockExpr(_it) => ImmediateLocation::BlockExpr,
197 ast::SourceFile(_it) => ImmediateLocation::ItemList,
198 ast::ItemList(_it) => ImmediateLocation::ItemList,
199 ast::RefExpr(_it) => ImmediateLocation::RefExpr,
200 ast::RecordField(it) => if it.ty().map_or(false, |it| it.syntax().text_range().contains(offset)) {
203 ImmediateLocation::RecordField
205 ast::TupleField(_it) => ImmediateLocation::TupleField,
206 ast::TupleFieldList(_it) => ImmediateLocation::TupleField,
207 ast::TypeBound(_it) => ImmediateLocation::TypeBound,
208 ast::TypeBoundList(_it) => ImmediateLocation::TypeBound,
209 ast::AssocItemList(it) => match it.syntax().parent().map(|it| it.kind()) {
210 Some(IMPL) => ImmediateLocation::Impl,
211 Some(TRAIT) => ImmediateLocation::Trait,
214 ast::GenericArgList(_it) => sema
215 .find_node_at_offset_with_macros(original_file, offset)
216 .map(ImmediateLocation::GenericArgList)?,
218 if it.item_list().is_none() {
219 ImmediateLocation::ModDeclaration(it)
224 ast::Attr(it) => ImmediateLocation::Attribute(it),
225 ast::FieldExpr(it) => {
228 .map(|e| e.syntax().text_range())
229 .and_then(|r| find_node_with_range(original_file, r));
230 let receiver_is_ambiguous_float_literal = if let Some(ast::Expr::Literal(l)) = &receiver {
232 ast::LiteralKind::FloatNumber { .. } => l.token().text().ends_with('.'),
238 ImmediateLocation::FieldAccess {
240 receiver_is_ambiguous_float_literal,
243 ast::MethodCallExpr(it) => ImmediateLocation::MethodCall {
246 .map(|e| e.syntax().text_range())
247 .and_then(|r| find_node_with_range(original_file, r)),
248 has_parens: it.arg_list().map_or(false, |it| it.l_paren_token().is_some())
250 ast::Visibility(it) => it.pub_token()
251 .and_then(|t| (t.text_range().end() < offset).then(|| ImmediateLocation::Visibility(it)))?,
258 fn maximize_name_ref(name_ref: &ast::NameRef) -> SyntaxNode {
259 // Maximize a nameref to its enclosing path if its the last segment of said path
260 if let Some(segment) = name_ref.syntax().parent().and_then(ast::PathSegment::cast) {
261 let p = segment.parent_path();
262 if p.parent_path().is_none() {
266 .take_while(|it| it.text_range() == p.syntax().text_range())
273 name_ref.syntax().clone()
276 fn find_node_with_range<N: AstNode>(syntax: &SyntaxNode, range: TextRange) -> Option<N> {
277 syntax.covering_element(range).ancestors().find_map(N::cast)
280 pub(crate) fn inside_impl_trait_block(element: SyntaxElement) -> bool {
281 // Here we search `impl` keyword up through the all ancestors, unlike in `has_impl_parent`,
282 // where we only check the first parent with different text range.
285 .find(|it| it.kind() == IMPL)
286 .map(|it| ast::Impl::cast(it).unwrap())
287 .map(|it| it.trait_().is_some())
291 fn test_inside_impl_trait_block() {
292 check_pattern_is_applicable(r"impl Foo for Bar { f$0 }", inside_impl_trait_block);
293 check_pattern_is_applicable(r"impl Foo for Bar { fn f$0 }", inside_impl_trait_block);
294 check_pattern_is_not_applicable(r"impl A { f$0 }", inside_impl_trait_block);
295 check_pattern_is_not_applicable(r"impl A { fn f$0 }", inside_impl_trait_block);
298 pub(crate) fn previous_token(element: SyntaxElement) -> Option<SyntaxToken> {
299 element.into_token().and_then(previous_non_trivia_token)
302 /// Check if the token previous to the previous one is `for`.
303 /// For example, `for _ i$0` => true.
304 pub(crate) fn for_is_prev2(element: SyntaxElement) -> bool {
307 .and_then(previous_non_trivia_token)
308 .and_then(previous_non_trivia_token)
309 .filter(|it| it.kind() == T![for])
313 fn test_for_is_prev2() {
314 check_pattern_is_applicable(r"for i i$0", for_is_prev2);
317 pub(crate) fn is_in_loop_body(node: &SyntaxNode) -> bool {
319 .take_while(|it| it.kind() != FN && it.kind() != CLOSURE_EXPR)
321 let loop_body = match_ast! {
323 ast::ForExpr(it) => it.loop_body(),
324 ast::WhileExpr(it) => it.loop_body(),
325 ast::LoopExpr(it) => it.loop_body(),
329 loop_body.filter(|it| it.syntax().text_range().contains_range(node.text_range()))
334 fn previous_non_trivia_token(token: SyntaxToken) -> Option<SyntaxToken> {
335 let mut token = token.prev_token();
336 while let Some(inner) = token.clone() {
337 if !inner.kind().is_trivia() {
340 token = inner.prev_token();
348 use syntax::algo::find_node_at_offset;
350 use crate::tests::position;
354 fn check_location(code: &str, loc: impl Into<Option<ImmediateLocation>>) {
355 let (db, pos) = position(code);
357 let sema = Semantics::new(&db);
358 let original_file = sema.parse(pos.file_id);
360 let name_like = find_node_at_offset(original_file.syntax(), pos.offset).unwrap();
362 determine_location(&sema, original_file.syntax(), pos.offset, &name_like),
367 fn check_prev_sibling(code: &str, sibling: impl Into<Option<ImmediatePrevSibling>>) {
368 check_pattern_is_applicable(code, |e| {
369 let name = &e.parent().and_then(ast::NameLike::cast).expect("Expected a namelike");
370 assert_eq!(determine_prev_sibling(name), sibling.into());
376 fn test_trait_loc() {
377 check_location(r"trait A { f$0 }", ImmediateLocation::Trait);
378 check_location(r"trait A { #[attr] f$0 }", ImmediateLocation::Trait);
379 check_location(r"trait A { f$0 fn f() {} }", ImmediateLocation::Trait);
380 check_location(r"trait A { fn f() {} f$0 }", ImmediateLocation::Trait);
381 check_location(r"trait A$0 {}", None);
382 check_location(r"trait A { fn f$0 }", None);
387 check_location(r"impl A { f$0 }", ImmediateLocation::Impl);
388 check_location(r"impl A { #[attr] f$0 }", ImmediateLocation::Impl);
389 check_location(r"impl A { f$0 fn f() {} }", ImmediateLocation::Impl);
390 check_location(r"impl A { fn f() {} f$0 }", ImmediateLocation::Impl);
391 check_location(r"impl A$0 {}", None);
392 check_location(r"impl A { fn f$0 }", None);
397 check_location(r"use f$0", ImmediateLocation::Use);
398 check_location(r"use f$0;", ImmediateLocation::Use);
399 check_location(r"use f::{f$0}", ImmediateLocation::UseTree);
400 check_location(r"use {f$0}", ImmediateLocation::UseTree);
404 fn test_record_field_loc() {
405 check_location(r"struct Foo { f$0 }", ImmediateLocation::RecordField);
406 check_location(r"struct Foo { f$0 pub f: i32}", ImmediateLocation::RecordField);
407 check_location(r"struct Foo { pub f: i32, f$0 }", ImmediateLocation::RecordField);
411 fn test_block_expr_loc() {
412 check_location(r"fn my_fn() { let a = 2; f$0 }", ImmediateLocation::BlockExpr);
413 check_location(r"fn my_fn() { f$0 f }", ImmediateLocation::BlockExpr);
417 fn test_ident_pat_loc() {
418 check_location(r"fn my_fn(m$0) {}", ImmediateLocation::IdentPat);
419 check_location(r"fn my_fn() { let m$0 }", ImmediateLocation::IdentPat);
420 check_location(r"fn my_fn(&m$0) {}", ImmediateLocation::IdentPat);
421 check_location(r"fn my_fn() { let &m$0 }", ImmediateLocation::IdentPat);
425 fn test_ref_expr_loc() {
426 check_location(r"fn my_fn() { let x = &m$0 foo; }", ImmediateLocation::RefExpr);
430 fn test_item_list_loc() {
431 check_location(r"i$0", ImmediateLocation::ItemList);
432 check_location(r"#[attr] i$0", ImmediateLocation::ItemList);
433 check_location(r"fn f() {} i$0", ImmediateLocation::ItemList);
434 check_location(r"mod foo { f$0 }", ImmediateLocation::ItemList);
435 check_location(r"mod foo { #[attr] f$0 }", ImmediateLocation::ItemList);
436 check_location(r"mod foo { fn f() {} f$0 }", ImmediateLocation::ItemList);
437 check_location(r"mod foo$0 {}", None);
441 fn test_impl_prev_sibling() {
442 check_prev_sibling(r"impl A w$0 ", ImmediatePrevSibling::ImplDefType);
443 check_prev_sibling(r"impl A w$0 {}", ImmediatePrevSibling::ImplDefType);
444 check_prev_sibling(r"impl A for A w$0 ", ImmediatePrevSibling::ImplDefType);
445 check_prev_sibling(r"impl A for A w$0 {}", ImmediatePrevSibling::ImplDefType);
446 check_prev_sibling(r"impl A for w$0 {}", None);
447 check_prev_sibling(r"impl A for w$0", None);
451 fn test_trait_prev_sibling() {
452 check_prev_sibling(r"trait A w$0 ", ImmediatePrevSibling::TraitDefName);
453 check_prev_sibling(r"trait A w$0 {}", ImmediatePrevSibling::TraitDefName);
457 fn test_if_expr_prev_sibling() {
458 check_prev_sibling(r"fn foo() { if true {} w$0", ImmediatePrevSibling::IfExpr);
459 check_prev_sibling(r"fn foo() { if true {}; w$0", None);
463 fn test_vis_prev_sibling() {
464 check_prev_sibling(r"pub w$0", ImmediatePrevSibling::Visibility);
468 fn test_attr_prev_sibling() {
469 check_prev_sibling(r"#[attr] w$0", ImmediatePrevSibling::Attribute);