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::test_utils::{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 {
25 /// Direct parent "thing" of what we are currently completing.
26 #[derive(Clone, Debug, PartialEq, Eq)]
27 pub(crate) enum ImmediateLocation {
39 ModDeclaration(ast::Module),
40 // Original file ast node
42 receiver: Option<ast::Expr>,
45 // Original file ast node
47 receiver: Option<ast::Expr>,
48 receiver_is_ambiguous_float_literal: bool,
50 // Original file ast node
51 // Only set from a type arg
52 GenericArgList(ast::GenericArgList),
53 // Original file ast node
54 /// The record expr of the field name we are completing
55 RecordExpr(ast::RecordExpr),
56 // Original file ast node
57 /// The record pat of the field name we are completing
58 RecordPat(ast::RecordPat),
61 pub(crate) fn determine_prev_sibling(name_like: &ast::NameLike) -> Option<ImmediatePrevSibling> {
62 let node = match name_like {
63 ast::NameLike::NameRef(name_ref) => maximize_name_ref(name_ref),
64 ast::NameLike::Name(n) => n.syntax().clone(),
65 ast::NameLike::Lifetime(lt) => lt.syntax().clone(),
67 let node = match node.parent().and_then(ast::MacroCall::cast) {
68 // When a path is being typed after the name of a trait/type of an impl it is being
69 // parsed as a macro, so when the trait/impl has a block following it an we are between the
70 // name and block the macro will attach the block to itself so maximizing fails to take
72 // FIXME path expr and statement have a similar problem with attrs
74 if call.excl_token().is_none()
75 && call.token_tree().map_or(false, |t| t.l_curly_token().is_some())
76 && call.semicolon_token().is_none() =>
82 let prev_sibling = non_trivia_sibling(node.into(), Direction::Prev)?.into_node()?;
83 if prev_sibling.kind() == ERROR {
84 let prev_sibling = prev_sibling.first_child()?;
85 let res = match_ast! {
87 // vis followed by random ident will always error the parser
88 ast::Visibility(_it) => ImmediatePrevSibling::Visibility,
94 let res = match_ast! {
96 ast::ExprStmt(it) => {
97 let node = it.expr().filter(|_| it.semicolon_token().is_none())?.syntax().clone();
100 ast::IfExpr(_it) => ImmediatePrevSibling::IfExpr,
105 ast::Trait(it) => if it.assoc_item_list().is_none() {
106 ImmediatePrevSibling::TraitDefName
110 ast::Impl(it) => if it.assoc_item_list().is_none()
111 && (it.for_token().is_none() || it.self_ty().is_some()) {
112 ImmediatePrevSibling::ImplDefType
122 pub(crate) fn determine_location(
123 sema: &Semantics<RootDatabase>,
124 original_file: &SyntaxNode,
126 name_like: &ast::NameLike,
127 ) -> Option<ImmediateLocation> {
128 let node = match name_like {
129 ast::NameLike::NameRef(name_ref) => {
130 if ast::RecordExprField::for_field_name(name_ref).is_some() {
132 .find_node_at_offset_with_macros(original_file, offset)
133 .map(ImmediateLocation::RecordExpr);
135 if ast::RecordPatField::for_field_name_ref(name_ref).is_some() {
137 .find_node_at_offset_with_macros(original_file, offset)
138 .map(ImmediateLocation::RecordPat);
140 maximize_name_ref(name_ref)
142 ast::NameLike::Name(name) => {
143 if ast::RecordPatField::for_field_name(name).is_some() {
145 .find_node_at_offset_with_macros(original_file, offset)
146 .map(ImmediateLocation::RecordPat);
148 name.syntax().clone()
150 ast::NameLike::Lifetime(lt) => lt.syntax().clone(),
153 let parent = match node.parent() {
154 Some(parent) => match ast::MacroCall::cast(parent.clone()) {
155 // When a path is being typed in an (Assoc)ItemList the parser will always emit a macro_call.
156 // This is usually fine as the node expansion code above already accounts for that with
157 // the ancestors call, but there is one exception to this which is that when an attribute
158 // precedes it the code above will not walk the Path to the parent MacroCall as their ranges differ.
159 // FIXME path expr and statement have a similar problem
161 if call.excl_token().is_none()
162 && call.token_tree().is_none()
163 && call.semicolon_token().is_none() =>
165 call.syntax().parent()?
171 return match node.kind() {
172 MACRO_ITEMS | SOURCE_FILE => Some(ImmediateLocation::ItemList),
177 let res = match_ast! {
179 ast::IdentPat(_it) => ImmediateLocation::IdentPat,
180 ast::Use(_it) => ImmediateLocation::Use,
181 ast::BlockExpr(_it) => ImmediateLocation::BlockExpr,
182 ast::SourceFile(_it) => ImmediateLocation::ItemList,
183 ast::ItemList(_it) => ImmediateLocation::ItemList,
184 ast::RefExpr(_it) => ImmediateLocation::RefExpr,
185 ast::RecordField(_it) => ImmediateLocation::RecordField,
186 ast::AssocItemList(it) => match it.syntax().parent().map(|it| it.kind()) {
187 Some(IMPL) => ImmediateLocation::Impl,
188 Some(TRAIT) => ImmediateLocation::Trait,
191 ast::GenericArgList(_it) => sema
192 .find_node_at_offset_with_macros(original_file, offset)
193 .map(ImmediateLocation::GenericArgList)?,
195 if it.item_list().is_none() {
196 ImmediateLocation::ModDeclaration(it)
201 ast::Attr(it) => ImmediateLocation::Attribute(it),
202 ast::FieldExpr(it) => {
205 .map(|e| e.syntax().text_range())
206 .and_then(|r| find_node_with_range(original_file, r));
207 let receiver_is_ambiguous_float_literal = if let Some(ast::Expr::Literal(l)) = &receiver {
209 ast::LiteralKind::FloatNumber { .. } => l.token().text().ends_with('.'),
215 ImmediateLocation::FieldAccess {
217 receiver_is_ambiguous_float_literal,
220 ast::MethodCallExpr(it) => ImmediateLocation::MethodCall {
223 .map(|e| e.syntax().text_range())
224 .and_then(|r| find_node_with_range(original_file, r)),
225 has_parens: it.arg_list().map_or(false, |it| it.l_paren_token().is_some())
233 fn maximize_name_ref(name_ref: &ast::NameRef) -> SyntaxNode {
234 // Maximize a nameref to its enclosing path if its the last segment of said path
235 if let Some(segment) = name_ref.syntax().parent().and_then(ast::PathSegment::cast) {
236 let p = segment.parent_path();
237 if p.parent_path().is_none() {
241 .take_while(|it| it.text_range() == p.syntax().text_range())
248 name_ref.syntax().clone()
251 fn find_node_with_range<N: AstNode>(syntax: &SyntaxNode, range: TextRange) -> Option<N> {
252 syntax.covering_element(range).ancestors().find_map(N::cast)
255 pub(crate) fn inside_impl_trait_block(element: SyntaxElement) -> bool {
256 // Here we search `impl` keyword up through the all ancestors, unlike in `has_impl_parent`,
257 // where we only check the first parent with different text range.
260 .find(|it| it.kind() == IMPL)
261 .map(|it| ast::Impl::cast(it).unwrap())
262 .map(|it| it.trait_().is_some())
266 fn test_inside_impl_trait_block() {
267 check_pattern_is_applicable(r"impl Foo for Bar { f$0 }", inside_impl_trait_block);
268 check_pattern_is_applicable(r"impl Foo for Bar { fn f$0 }", inside_impl_trait_block);
269 check_pattern_is_not_applicable(r"impl A { f$0 }", inside_impl_trait_block);
270 check_pattern_is_not_applicable(r"impl A { fn f$0 }", inside_impl_trait_block);
273 pub(crate) fn previous_token(element: SyntaxElement) -> Option<SyntaxToken> {
274 element.into_token().and_then(previous_non_trivia_token)
277 /// Check if the token previous to the previous one is `for`.
278 /// For example, `for _ i$0` => true.
279 pub(crate) fn for_is_prev2(element: SyntaxElement) -> bool {
282 .and_then(previous_non_trivia_token)
283 .and_then(previous_non_trivia_token)
284 .filter(|it| it.kind() == T![for])
288 fn test_for_is_prev2() {
289 check_pattern_is_applicable(r"for i i$0", for_is_prev2);
292 pub(crate) fn is_in_loop_body(node: &SyntaxNode) -> bool {
294 .take_while(|it| it.kind() != FN && it.kind() != CLOSURE_EXPR)
296 let loop_body = match_ast! {
298 ast::ForExpr(it) => it.loop_body(),
299 ast::WhileExpr(it) => it.loop_body(),
300 ast::LoopExpr(it) => it.loop_body(),
304 loop_body.filter(|it| it.syntax().text_range().contains_range(node.text_range()))
309 fn previous_non_trivia_token(token: SyntaxToken) -> Option<SyntaxToken> {
310 let mut token = token.prev_token();
311 while let Some(inner) = token.clone() {
312 if !inner.kind().is_trivia() {
315 token = inner.prev_token();
323 use syntax::algo::find_node_at_offset;
325 use crate::test_utils::position;
329 fn check_location(code: &str, loc: impl Into<Option<ImmediateLocation>>) {
330 let (db, pos) = position(code);
332 let sema = Semantics::new(&db);
333 let original_file = sema.parse(pos.file_id);
335 let name_like = find_node_at_offset(original_file.syntax(), pos.offset).unwrap();
337 determine_location(&sema, original_file.syntax(), pos.offset, &name_like),
342 fn check_prev_sibling(code: &str, sibling: impl Into<Option<ImmediatePrevSibling>>) {
343 check_pattern_is_applicable(code, |e| {
344 let name = &e.parent().and_then(ast::NameLike::cast).expect("Expected a namelike");
345 assert_eq!(determine_prev_sibling(name), sibling.into());
351 fn test_trait_loc() {
352 check_location(r"trait A { f$0 }", ImmediateLocation::Trait);
353 check_location(r"trait A { #[attr] f$0 }", ImmediateLocation::Trait);
354 check_location(r"trait A { f$0 fn f() {} }", ImmediateLocation::Trait);
355 check_location(r"trait A { fn f() {} f$0 }", ImmediateLocation::Trait);
356 check_location(r"trait A$0 {}", None);
357 check_location(r"trait A { fn f$0 }", None);
362 check_location(r"impl A { f$0 }", ImmediateLocation::Impl);
363 check_location(r"impl A { #[attr] f$0 }", ImmediateLocation::Impl);
364 check_location(r"impl A { f$0 fn f() {} }", ImmediateLocation::Impl);
365 check_location(r"impl A { fn f() {} f$0 }", ImmediateLocation::Impl);
366 check_location(r"impl A$0 {}", None);
367 check_location(r"impl A { fn f$0 }", None);
372 check_location(r"use f$0", ImmediateLocation::Use);
373 check_location(r"use f$0;", ImmediateLocation::Use);
374 check_location(r"use f::{f$0}", None);
375 check_location(r"use {f$0}", None);
379 fn test_record_field_loc() {
380 check_location(r"struct Foo { f$0 }", ImmediateLocation::RecordField);
381 check_location(r"struct Foo { f$0 pub f: i32}", ImmediateLocation::RecordField);
382 check_location(r"struct Foo { pub f: i32, f$0 }", ImmediateLocation::RecordField);
386 fn test_block_expr_loc() {
387 check_location(r"fn my_fn() { let a = 2; f$0 }", ImmediateLocation::BlockExpr);
388 check_location(r"fn my_fn() { f$0 f }", ImmediateLocation::BlockExpr);
392 fn test_ident_pat_loc() {
393 check_location(r"fn my_fn(m$0) {}", ImmediateLocation::IdentPat);
394 check_location(r"fn my_fn() { let m$0 }", ImmediateLocation::IdentPat);
395 check_location(r"fn my_fn(&m$0) {}", ImmediateLocation::IdentPat);
396 check_location(r"fn my_fn() { let &m$0 }", ImmediateLocation::IdentPat);
400 fn test_ref_expr_loc() {
401 check_location(r"fn my_fn() { let x = &m$0 foo; }", ImmediateLocation::RefExpr);
405 fn test_item_list_loc() {
406 check_location(r"i$0", ImmediateLocation::ItemList);
407 check_location(r"#[attr] i$0", ImmediateLocation::ItemList);
408 check_location(r"fn f() {} i$0", ImmediateLocation::ItemList);
409 check_location(r"mod foo { f$0 }", ImmediateLocation::ItemList);
410 check_location(r"mod foo { #[attr] f$0 }", ImmediateLocation::ItemList);
411 check_location(r"mod foo { fn f() {} f$0 }", ImmediateLocation::ItemList);
412 check_location(r"mod foo$0 {}", None);
416 fn test_impl_prev_sibling() {
417 check_prev_sibling(r"impl A w$0 ", ImmediatePrevSibling::ImplDefType);
418 check_prev_sibling(r"impl A w$0 {}", ImmediatePrevSibling::ImplDefType);
419 check_prev_sibling(r"impl A for A w$0 ", ImmediatePrevSibling::ImplDefType);
420 check_prev_sibling(r"impl A for A w$0 {}", ImmediatePrevSibling::ImplDefType);
421 check_prev_sibling(r"impl A for w$0 {}", None);
422 check_prev_sibling(r"impl A for w$0", None);
426 fn test_trait_prev_sibling() {
427 check_prev_sibling(r"trait A w$0 ", ImmediatePrevSibling::TraitDefName);
428 check_prev_sibling(r"trait A w$0 {}", ImmediatePrevSibling::TraitDefName);
432 fn test_if_expr_prev_sibling() {
433 check_prev_sibling(r"fn foo() { if true {} w$0", ImmediatePrevSibling::IfExpr);
434 check_prev_sibling(r"fn foo() { if true {}; w$0", None);
438 fn test_vis_prev_sibling() {
439 check_prev_sibling(r"pub w$0", ImmediatePrevSibling::Visibility);