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 {
24 /// Direct parent "thing" of what we are currently completing.
25 #[derive(Clone, Debug, PartialEq, Eq)]
26 pub(crate) enum ImmediateLocation {
38 ModDeclaration(ast::Module),
39 // Original file ast node
41 receiver: Option<ast::Expr>,
44 // Original file ast node
46 receiver: Option<ast::Expr>,
47 receiver_is_ambiguous_float_literal: bool,
49 // Original file ast node
50 // Only set from a type arg
51 GenericArgList(ast::GenericArgList),
52 // Original file ast node
53 /// The record expr of the field name we are completing
54 RecordExpr(ast::RecordExpr),
55 // Original file ast node
56 /// The record pat of the field name we are completing
57 RecordPat(ast::RecordPat),
60 pub(crate) fn determine_prev_sibling(name_like: &ast::NameLike) -> Option<ImmediatePrevSibling> {
61 let node = match name_like {
62 ast::NameLike::NameRef(name_ref) => maximize_name_ref(name_ref),
63 ast::NameLike::Name(n) => n.syntax().clone(),
64 ast::NameLike::Lifetime(lt) => lt.syntax().clone(),
66 let node = match node.parent().and_then(ast::MacroCall::cast) {
67 // When a path is being typed after the name of a trait/type of an impl it is being
68 // parsed as a macro, so when the trait/impl has a block following it an we are between the
69 // name and block the macro will attach the block to itself so maximizing fails to take
71 // FIXME path expr and statement have a similar problem with attrs
73 if call.excl_token().is_none()
74 && call.token_tree().map_or(false, |t| t.l_curly_token().is_some())
75 && call.semicolon_token().is_none() =>
81 let prev_sibling = non_trivia_sibling(node.into(), Direction::Prev)?.into_node()?;
82 let res = match_ast! {
84 ast::ExprStmt(it) => {
85 let node = it.expr().filter(|_| it.semicolon_token().is_none())?.syntax().clone();
88 ast::IfExpr(_it) => ImmediatePrevSibling::IfExpr,
93 ast::Trait(it) => if it.assoc_item_list().is_none() {
94 ImmediatePrevSibling::TraitDefName
98 ast::Impl(it) => if it.assoc_item_list().is_none()
99 && (it.for_token().is_none() || it.self_ty().is_some()) {
100 ImmediatePrevSibling::ImplDefType
110 pub(crate) fn determine_location(
111 sema: &Semantics<RootDatabase>,
112 original_file: &SyntaxNode,
114 name_like: &ast::NameLike,
115 ) -> Option<ImmediateLocation> {
116 let node = match name_like {
117 ast::NameLike::NameRef(name_ref) => {
118 if ast::RecordExprField::for_field_name(name_ref).is_some() {
120 .find_node_at_offset_with_macros(original_file, offset)
121 .map(ImmediateLocation::RecordExpr);
123 if ast::RecordPatField::for_field_name_ref(name_ref).is_some() {
125 .find_node_at_offset_with_macros(original_file, offset)
126 .map(ImmediateLocation::RecordPat);
128 maximize_name_ref(name_ref)
130 ast::NameLike::Name(name) => {
131 if ast::RecordPatField::for_field_name(name).is_some() {
133 .find_node_at_offset_with_macros(original_file, offset)
134 .map(ImmediateLocation::RecordPat);
136 name.syntax().clone()
138 ast::NameLike::Lifetime(lt) => lt.syntax().clone(),
141 let parent = match node.parent() {
142 Some(parent) => match ast::MacroCall::cast(parent.clone()) {
143 // When a path is being typed in an (Assoc)ItemList the parser will always emit a macro_call.
144 // This is usually fine as the node expansion code above already accounts for that with
145 // the ancestors call, but there is one exception to this which is that when an attribute
146 // precedes it the code above will not walk the Path to the parent MacroCall as their ranges differ.
147 // FIXME path expr and statement have a similar problem
149 if call.excl_token().is_none()
150 && call.token_tree().is_none()
151 && call.semicolon_token().is_none() =>
153 call.syntax().parent()?
159 return match node.kind() {
160 MACRO_ITEMS | SOURCE_FILE => Some(ImmediateLocation::ItemList),
165 let res = match_ast! {
167 ast::IdentPat(_it) => ImmediateLocation::IdentPat,
168 ast::Use(_it) => ImmediateLocation::Use,
169 ast::BlockExpr(_it) => ImmediateLocation::BlockExpr,
170 ast::SourceFile(_it) => ImmediateLocation::ItemList,
171 ast::ItemList(_it) => ImmediateLocation::ItemList,
172 ast::RefExpr(_it) => ImmediateLocation::RefExpr,
173 ast::RecordField(_it) => ImmediateLocation::RecordField,
174 ast::AssocItemList(it) => match it.syntax().parent().map(|it| it.kind()) {
175 Some(IMPL) => ImmediateLocation::Impl,
176 Some(TRAIT) => ImmediateLocation::Trait,
179 ast::GenericArgList(_it) => sema
180 .find_node_at_offset_with_macros(original_file, offset)
181 .map(ImmediateLocation::GenericArgList)?,
183 if it.item_list().is_none() {
184 ImmediateLocation::ModDeclaration(it)
189 ast::Attr(it) => ImmediateLocation::Attribute(it),
190 ast::FieldExpr(it) => {
193 .map(|e| e.syntax().text_range())
194 .and_then(|r| find_node_with_range(original_file, r));
195 let receiver_is_ambiguous_float_literal = if let Some(ast::Expr::Literal(l)) = &receiver {
197 ast::LiteralKind::FloatNumber { .. } => l.token().text().ends_with('.'),
203 ImmediateLocation::FieldAccess {
205 receiver_is_ambiguous_float_literal,
208 ast::MethodCallExpr(it) => ImmediateLocation::MethodCall {
211 .map(|e| e.syntax().text_range())
212 .and_then(|r| find_node_with_range(original_file, r)),
213 has_parens: it.arg_list().map_or(false, |it| it.l_paren_token().is_some())
221 fn maximize_name_ref(name_ref: &ast::NameRef) -> SyntaxNode {
222 // Maximize a nameref to its enclosing path if its the last segment of said path
223 if let Some(segment) = name_ref.syntax().parent().and_then(ast::PathSegment::cast) {
224 let p = segment.parent_path();
225 if p.parent_path().is_none() {
229 .take_while(|it| it.text_range() == p.syntax().text_range())
236 name_ref.syntax().clone()
239 fn find_node_with_range<N: AstNode>(syntax: &SyntaxNode, range: TextRange) -> Option<N> {
240 syntax.covering_element(range).ancestors().find_map(N::cast)
243 pub(crate) fn inside_impl_trait_block(element: SyntaxElement) -> bool {
244 // Here we search `impl` keyword up through the all ancestors, unlike in `has_impl_parent`,
245 // where we only check the first parent with different text range.
248 .find(|it| it.kind() == IMPL)
249 .map(|it| ast::Impl::cast(it).unwrap())
250 .map(|it| it.trait_().is_some())
254 fn test_inside_impl_trait_block() {
255 check_pattern_is_applicable(r"impl Foo for Bar { f$0 }", inside_impl_trait_block);
256 check_pattern_is_applicable(r"impl Foo for Bar { fn f$0 }", inside_impl_trait_block);
257 check_pattern_is_not_applicable(r"impl A { f$0 }", inside_impl_trait_block);
258 check_pattern_is_not_applicable(r"impl A { fn f$0 }", inside_impl_trait_block);
261 pub(crate) fn previous_token(element: SyntaxElement) -> Option<SyntaxToken> {
262 element.into_token().and_then(previous_non_trivia_token)
265 /// Check if the token previous to the previous one is `for`.
266 /// For example, `for _ i$0` => true.
267 pub(crate) fn for_is_prev2(element: SyntaxElement) -> bool {
270 .and_then(previous_non_trivia_token)
271 .and_then(previous_non_trivia_token)
272 .filter(|it| it.kind() == T![for])
276 fn test_for_is_prev2() {
277 check_pattern_is_applicable(r"for i i$0", for_is_prev2);
280 pub(crate) fn is_in_loop_body(node: &SyntaxNode) -> bool {
282 .take_while(|it| it.kind() != FN && it.kind() != CLOSURE_EXPR)
284 let loop_body = match_ast! {
286 ast::ForExpr(it) => it.loop_body(),
287 ast::WhileExpr(it) => it.loop_body(),
288 ast::LoopExpr(it) => it.loop_body(),
292 loop_body.filter(|it| it.syntax().text_range().contains_range(node.text_range()))
297 fn previous_non_trivia_token(token: SyntaxToken) -> Option<SyntaxToken> {
298 let mut token = token.prev_token();
299 while let Some(inner) = token.clone() {
300 if !inner.kind().is_trivia() {
303 token = inner.prev_token();
311 use syntax::algo::find_node_at_offset;
313 use crate::test_utils::position;
317 fn check_location(code: &str, loc: impl Into<Option<ImmediateLocation>>) {
318 let (db, pos) = position(code);
320 let sema = Semantics::new(&db);
321 let original_file = sema.parse(pos.file_id);
323 let name_like = find_node_at_offset(original_file.syntax(), pos.offset).unwrap();
325 determine_location(&sema, original_file.syntax(), pos.offset, &name_like),
330 fn check_prev_sibling(code: &str, sibling: impl Into<Option<ImmediatePrevSibling>>) {
331 check_pattern_is_applicable(code, |e| {
332 let name = &e.parent().and_then(ast::NameLike::cast).expect("Expected a namelike");
333 assert_eq!(determine_prev_sibling(name), sibling.into());
339 fn test_trait_loc() {
340 check_location(r"trait A { f$0 }", ImmediateLocation::Trait);
341 check_location(r"trait A { #[attr] f$0 }", ImmediateLocation::Trait);
342 check_location(r"trait A { f$0 fn f() {} }", ImmediateLocation::Trait);
343 check_location(r"trait A { fn f() {} f$0 }", ImmediateLocation::Trait);
344 check_location(r"trait A$0 {}", None);
345 check_location(r"trait A { fn f$0 }", None);
350 check_location(r"impl A { f$0 }", ImmediateLocation::Impl);
351 check_location(r"impl A { #[attr] f$0 }", ImmediateLocation::Impl);
352 check_location(r"impl A { f$0 fn f() {} }", ImmediateLocation::Impl);
353 check_location(r"impl A { fn f() {} f$0 }", ImmediateLocation::Impl);
354 check_location(r"impl A$0 {}", None);
355 check_location(r"impl A { fn f$0 }", None);
360 check_location(r"use f$0", ImmediateLocation::Use);
361 check_location(r"use f$0;", ImmediateLocation::Use);
362 check_location(r"use f::{f$0}", None);
363 check_location(r"use {f$0}", None);
367 fn test_record_field_loc() {
368 check_location(r"struct Foo { f$0 }", ImmediateLocation::RecordField);
369 check_location(r"struct Foo { f$0 pub f: i32}", ImmediateLocation::RecordField);
370 check_location(r"struct Foo { pub f: i32, f$0 }", ImmediateLocation::RecordField);
374 fn test_block_expr_loc() {
375 check_location(r"fn my_fn() { let a = 2; f$0 }", ImmediateLocation::BlockExpr);
376 check_location(r"fn my_fn() { f$0 f }", ImmediateLocation::BlockExpr);
380 fn test_ident_pat_loc() {
381 check_location(r"fn my_fn(m$0) {}", ImmediateLocation::IdentPat);
382 check_location(r"fn my_fn() { let m$0 }", ImmediateLocation::IdentPat);
383 check_location(r"fn my_fn(&m$0) {}", ImmediateLocation::IdentPat);
384 check_location(r"fn my_fn() { let &m$0 }", ImmediateLocation::IdentPat);
388 fn test_ref_expr_loc() {
389 check_location(r"fn my_fn() { let x = &m$0 foo; }", ImmediateLocation::RefExpr);
393 fn test_item_list_loc() {
394 check_location(r"i$0", ImmediateLocation::ItemList);
395 check_location(r"#[attr] i$0", ImmediateLocation::ItemList);
396 check_location(r"fn f() {} i$0", ImmediateLocation::ItemList);
397 check_location(r"mod foo { f$0 }", ImmediateLocation::ItemList);
398 check_location(r"mod foo { #[attr] f$0 }", ImmediateLocation::ItemList);
399 check_location(r"mod foo { fn f() {} f$0 }", ImmediateLocation::ItemList);
400 check_location(r"mod foo$0 {}", None);
404 fn test_impl_prev_sibling() {
405 check_prev_sibling(r"impl A w$0 ", ImmediatePrevSibling::ImplDefType);
406 check_prev_sibling(r"impl A w$0 {}", ImmediatePrevSibling::ImplDefType);
407 check_prev_sibling(r"impl A for A w$0 ", ImmediatePrevSibling::ImplDefType);
408 check_prev_sibling(r"impl A for A w$0 {}", ImmediatePrevSibling::ImplDefType);
409 check_prev_sibling(r"impl A for w$0 {}", None);
410 check_prev_sibling(r"impl A for w$0", None);
414 fn test_trait_prev_sibling() {
415 check_prev_sibling(r"trait A w$0 ", ImmediatePrevSibling::TraitDefName);
416 check_prev_sibling(r"trait A w$0 {}", ImmediatePrevSibling::TraitDefName);
420 fn test_if_expr_prev_sibling() {
421 check_prev_sibling(r"fn foo() { if true {} w$0", ImmediatePrevSibling::IfExpr);
422 check_prev_sibling(r"fn foo() { if true {}; w$0", None);