crates/ide_completion/src/context.rs

   1 //! See `CompletionContext` structure.
   2
   3 use std::iter;
   4
   5 use base_db::SourceDatabaseExt;
   6 use hir::{HasAttrs, Local, Name, ScopeDef, Semantics, SemanticsScope, Type, TypeInfo};
   7 use ide_db::{
   8     active_parameter::ActiveParameter,
   9     base_db::{FilePosition, SourceDatabase},
  10     helpers::FamousDefs,
  11     RootDatabase,
  12 };
  13 use syntax::{
  14     algo::find_node_at_offset,
  15     ast::{self, HasName, NameOrNameRef},
  16     match_ast, AstNode, NodeOrToken,
  17     SyntaxKind::{self, *},
  18     SyntaxNode, SyntaxToken, TextRange, TextSize, T,
  19 };
  20 use text_edit::Indel;
  21
  22 use crate::{
  23     patterns::{
  24         determine_location, determine_prev_sibling, for_is_prev2, inside_impl_trait_block,
  25         is_in_loop_body, previous_token, ImmediateLocation, ImmediatePrevSibling,
  26     },
  27     CompletionConfig,
  28 };
  29
  30 const COMPLETION_MARKER: &str = "intellijRulezz";
  31
  32 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
  33 pub(crate) enum PatternRefutability {
  34     Refutable,
  35     Irrefutable,
  36 }
  37
  38 #[derive(Copy, Clone, Debug)]
  39 pub(super) enum PathKind {
  40     Expr,
  41     Type,
  42     Attr,
  43     Mac,
  44     Pat,
  45     Vis { has_in_token: bool },
  46     Use,
  47 }
  48
  49 #[derive(Debug)]
  50 pub(crate) struct PathCompletionContext {
  51     /// If this is a call with () already there
  52     has_call_parens: bool,
  53     /// A single-indent path, like `foo`. `::foo` should not be considered a trivial path.
  54     pub(super) is_trivial_path: bool,
  55     /// If not a trivial path, the prefix (qualifier).
  56     pub(super) qualifier: Option<ast::Path>,
  57     #[allow(dead_code)]
  58     /// If not a trivial path, the suffix (parent).
  59     pub(super) parent: Option<ast::Path>,
  60     /// Whether the qualifier comes from a use tree parent or not
  61     pub(super) use_tree_parent: bool,
  62     pub(super) kind: Option<PathKind>,
  63     /// Whether the path segment has type args or not.
  64     pub(super) has_type_args: bool,
  65     /// `true` if we are a statement or a last expr in the block.
  66     pub(super) can_be_stmt: bool,
  67     pub(super) in_loop_body: bool,
  68 }
  69
  70 #[derive(Debug)]
  71 pub(super) struct PatternContext {
  72     pub(super) refutability: PatternRefutability,
  73     pub(super) param_ctx: Option<(ast::ParamList, ast::Param, ParamKind)>,
  74     pub(super) has_type_ascription: bool,
  75 }
  76
  77 #[derive(Debug)]
  78 pub(super) enum LifetimeContext {
  79     LifetimeParam(Option<ast::LifetimeParam>),
  80     Lifetime,
  81     LabelRef,
  82     LabelDef,
  83 }
  84
  85 #[derive(Clone, Debug, PartialEq, Eq)]
  86 pub(crate) enum ParamKind {
  87     Function(ast::Fn),
  88     Closure(ast::ClosureExpr),
  89 }
  90
  91 /// `CompletionContext` is created early during completion to figure out, where
  92 /// exactly is the cursor, syntax-wise.
  93 #[derive(Debug)]
  94 pub(crate) struct CompletionContext<'a> {
  95     pub(super) sema: Semantics<'a, RootDatabase>,
  96     pub(super) scope: SemanticsScope<'a>,
  97     pub(super) db: &'a RootDatabase,
  98     pub(super) config: &'a CompletionConfig,
  99     pub(super) position: FilePosition,
 100     /// The token before the cursor, in the original file.
 101     pub(super) original_token: SyntaxToken,
 102     /// The token before the cursor, in the macro-expanded file.
 103     pub(super) token: SyntaxToken,
 104     /// The crate of the current file.
 105     pub(super) krate: Option<hir::Crate>,
 106     /// The crate of the `scope`.
 107     pub(super) module: Option<hir::Module>,
 108     pub(super) expected_name: Option<NameOrNameRef>,
 109     pub(super) expected_type: Option<Type>,
 110
 111     /// The parent function of the cursor position if it exists.
 112     pub(super) function_def: Option<ast::Fn>,
 113     pub(super) attr: Option<ast::Attr>,
 114     /// The parent impl of the cursor position if it exists.
 115     pub(super) impl_def: Option<ast::Impl>,
 116     /// The NameLike under the cursor in the original file if it exists.
 117     pub(super) name_syntax: Option<ast::NameLike>,
 118     pub(super) incomplete_let: bool,
 119
 120     pub(super) completion_location: Option<ImmediateLocation>,
 121     pub(super) prev_sibling: Option<ImmediatePrevSibling>,
 122     pub(super) fake_attribute_under_caret: Option<ast::Attr>,
 123     pub(super) previous_token: Option<SyntaxToken>,
 124
 125     pub(super) lifetime_ctx: Option<LifetimeContext>,
 126     pub(super) pattern_ctx: Option<PatternContext>,
 127     pub(super) path_context: Option<PathCompletionContext>,
 128
 129     pub(super) locals: Vec<(Name, Local)>,
 130
 131     no_completion_required: bool,
 132 }
 133
 134 impl<'a> CompletionContext<'a> {
 135     /// Checks whether completions in that particular case don't make much sense.
 136     /// Examples:
 137     /// - `fn $0` -- we expect function name, it's unlikely that "hint" will be helpful.
 138     ///   Exception for this case is `impl Trait for Foo`, where we would like to hint trait method names.
 139     /// - `for _ i$0` -- obviously, it'll be "in" keyword.
 140     pub(crate) fn no_completion_required(&self) -> bool {
 141         self.no_completion_required
 142     }
 143
 144     /// The range of the identifier that is being completed.
 145     pub(crate) fn source_range(&self) -> TextRange {
 146         // check kind of macro-expanded token, but use range of original token
 147         let kind = self.token.kind();
 148         if kind == IDENT || kind == LIFETIME_IDENT || kind == UNDERSCORE || kind.is_keyword() {
 149             self.original_token.text_range()
 150         } else if kind == CHAR {
 151             // assume we are completing a lifetime but the user has only typed the '
 152             cov_mark::hit!(completes_if_lifetime_without_idents);
 153             TextRange::at(self.original_token.text_range().start(), TextSize::from(1))
 154         } else {
 155             TextRange::empty(self.position.offset)
 156         }
 157     }
 158
 159     pub(crate) fn previous_token_is(&self, kind: SyntaxKind) -> bool {
 160         self.previous_token.as_ref().map_or(false, |tok| tok.kind() == kind)
 161     }
 162
 163     pub(crate) fn famous_defs(&self) -> FamousDefs {
 164         FamousDefs(&self.sema, self.krate)
 165     }
 166
 167     pub(crate) fn dot_receiver(&self) -> Option<&ast::Expr> {
 168         match &self.completion_location {
 169             Some(
 170                 ImmediateLocation::MethodCall { receiver, .. }
 171                 | ImmediateLocation::FieldAccess { receiver, .. },
 172             ) => receiver.as_ref(),
 173             _ => None,
 174         }
 175     }
 176
 177     pub(crate) fn has_dot_receiver(&self) -> bool {
 178         matches!(
 179             &self.completion_location,
 180             Some(ImmediateLocation::FieldAccess { receiver, .. } | ImmediateLocation::MethodCall { receiver,.. })
 181                 if receiver.is_some()
 182         )
 183     }
 184
 185     pub(crate) fn expects_assoc_item(&self) -> bool {
 186         matches!(self.completion_location, Some(ImmediateLocation::Trait | ImmediateLocation::Impl))
 187     }
 188
 189     pub(crate) fn expects_variant(&self) -> bool {
 190         matches!(self.completion_location, Some(ImmediateLocation::Variant))
 191     }
 192
 193     pub(crate) fn expects_non_trait_assoc_item(&self) -> bool {
 194         matches!(self.completion_location, Some(ImmediateLocation::Impl))
 195     }
 196
 197     pub(crate) fn expects_item(&self) -> bool {
 198         matches!(self.completion_location, Some(ImmediateLocation::ItemList))
 199     }
 200
 201     pub(crate) fn expects_generic_arg(&self) -> bool {
 202         matches!(self.completion_location, Some(ImmediateLocation::GenericArgList(_)))
 203     }
 204
 205     pub(crate) fn has_block_expr_parent(&self) -> bool {
 206         matches!(self.completion_location, Some(ImmediateLocation::StmtList))
 207     }
 208
 209     pub(crate) fn expects_ident_pat_or_ref_expr(&self) -> bool {
 210         matches!(
 211             self.completion_location,
 212             Some(ImmediateLocation::IdentPat | ImmediateLocation::RefExpr)
 213         )
 214     }
 215
 216     pub(crate) fn expect_field(&self) -> bool {
 217         matches!(
 218             self.completion_location,
 219             Some(ImmediateLocation::RecordField | ImmediateLocation::TupleField)
 220         )
 221     }
 222
 223     pub(crate) fn has_impl_or_trait_prev_sibling(&self) -> bool {
 224         matches!(
 225             self.prev_sibling,
 226             Some(ImmediatePrevSibling::ImplDefType | ImmediatePrevSibling::TraitDefName)
 227         )
 228     }
 229
 230     pub(crate) fn has_impl_prev_sibling(&self) -> bool {
 231         matches!(self.prev_sibling, Some(ImmediatePrevSibling::ImplDefType))
 232     }
 233
 234     pub(crate) fn has_visibility_prev_sibling(&self) -> bool {
 235         matches!(self.prev_sibling, Some(ImmediatePrevSibling::Visibility))
 236     }
 237
 238     pub(crate) fn after_if(&self) -> bool {
 239         matches!(self.prev_sibling, Some(ImmediatePrevSibling::IfExpr))
 240     }
 241
 242     pub(crate) fn is_path_disallowed(&self) -> bool {
 243         self.previous_token_is(T![unsafe])
 244             || matches!(
 245                 self.prev_sibling,
 246                 Some(ImmediatePrevSibling::Attribute | ImmediatePrevSibling::Visibility)
 247             )
 248             || matches!(
 249                 self.completion_location,
 250                 Some(
 251                     ImmediateLocation::ModDeclaration(_)
 252                         | ImmediateLocation::RecordPat(_)
 253                         | ImmediateLocation::RecordExpr(_)
 254                         | ImmediateLocation::Rename
 255                 )
 256             )
 257     }
 258
 259     pub(crate) fn expects_expression(&self) -> bool {
 260         matches!(self.path_context, Some(PathCompletionContext { kind: Some(PathKind::Expr), .. }))
 261     }
 262
 263     pub(crate) fn expects_type(&self) -> bool {
 264         matches!(self.path_context, Some(PathCompletionContext { kind: Some(PathKind::Type), .. }))
 265     }
 266
 267     pub(crate) fn path_is_call(&self) -> bool {
 268         self.path_context.as_ref().map_or(false, |it| it.has_call_parens)
 269     }
 270
 271     pub(crate) fn is_trivial_path(&self) -> bool {
 272         matches!(self.path_context, Some(PathCompletionContext { is_trivial_path: true, .. }))
 273     }
 274
 275     pub(crate) fn is_non_trivial_path(&self) -> bool {
 276         matches!(self.path_context, Some(PathCompletionContext { is_trivial_path: false, .. }))
 277     }
 278
 279     pub(crate) fn path_qual(&self) -> Option<&ast::Path> {
 280         self.path_context.as_ref().and_then(|it| it.qualifier.as_ref())
 281     }
 282
 283     pub(crate) fn path_kind(&self) -> Option<PathKind> {
 284         self.path_context.as_ref().and_then(|it| it.kind)
 285     }
 286
 287     /// Checks if an item is visible and not `doc(hidden)` at the completion site.
 288     pub(crate) fn is_visible<I>(&self, item: &I) -> bool
 289     where
 290         I: hir::HasVisibility + hir::HasAttrs + hir::HasCrate + Copy,
 291     {
 292         self.is_visible_impl(&item.visibility(self.db), &item.attrs(self.db), item.krate(self.db))
 293     }
 294
 295     pub(crate) fn is_scope_def_hidden(&self, scope_def: ScopeDef) -> bool {
 296         if let (Some(attrs), Some(krate)) = (scope_def.attrs(self.db), scope_def.krate(self.db)) {
 297             return self.is_doc_hidden(&attrs, krate);
 298         }
 299
 300         false
 301     }
 302
 303     /// Check if an item is `#[doc(hidden)]`.
 304     pub(crate) fn is_item_hidden(&self, item: &hir::ItemInNs) -> bool {
 305         let attrs = item.attrs(self.db);
 306         let krate = item.krate(self.db);
 307         match (attrs, krate) {
 308             (Some(attrs), Some(krate)) => self.is_doc_hidden(&attrs, krate),
 309             _ => false,
 310         }
 311     }
 312
 313     pub(crate) fn is_immediately_after_macro_bang(&self) -> bool {
 314         self.token.kind() == BANG && self.token.parent().map_or(false, |it| it.kind() == MACRO_CALL)
 315     }
 316
 317     /// Whether the given trait is an operator trait or not.
 318     pub(crate) fn is_ops_trait(&self, trait_: hir::Trait) -> bool {
 319         match trait_.attrs(self.db).lang() {
 320             Some(lang) => OP_TRAIT_LANG_NAMES.contains(&lang.as_str()),
 321             None => false,
 322         }
 323     }
 324
 325     /// A version of [`SemanticsScope::process_all_names`] that filters out `#[doc(hidden)]` items.
 326     pub(crate) fn process_all_names(&self, f: &mut dyn FnMut(Name, ScopeDef)) {
 327         let _p = profile::span("CompletionContext::process_all_names");
 328         self.scope.process_all_names(&mut |name, def| {
 329             if self.is_scope_def_hidden(def) {
 330                 return;
 331             }
 332
 333             f(name, def);
 334         })
 335     }
 336
 337     fn is_visible_impl(
 338         &self,
 339         vis: &hir::Visibility,
 340         attrs: &hir::Attrs,
 341         defining_crate: hir::Crate,
 342     ) -> bool {
 343         let module = match self.module {
 344             Some(it) => it,
 345             None => return false,
 346         };
 347         if !vis.is_visible_from(self.db, module.into()) {
 348             // If the definition location is editable, also show private items
 349             let root_file = defining_crate.root_file(self.db);
 350             let source_root_id = self.db.file_source_root(root_file);
 351             let is_editable = !self.db.source_root(source_root_id).is_library;
 352             return is_editable;
 353         }
 354
 355         !self.is_doc_hidden(attrs, defining_crate)
 356     }
 357
 358     fn is_doc_hidden(&self, attrs: &hir::Attrs, defining_crate: hir::Crate) -> bool {
 359         let krate = match self.krate {
 360             Some(it) => it,
 361             None => return true,
 362         };
 363         if krate != defining_crate && attrs.has_doc_hidden() {
 364             // `doc(hidden)` items are only completed within the defining crate.
 365             return true;
 366         }
 367
 368         false
 369     }
 370 }
 371
 372 // CompletionContext construction
 373 impl<'a> CompletionContext<'a> {
 374     pub(super) fn new(
 375         db: &'a RootDatabase,
 376         position @ FilePosition { file_id, offset }: FilePosition,
 377         config: &'a CompletionConfig,
 378     ) -> Option<CompletionContext<'a>> {
 379         let _p = profile::span("CompletionContext::new");
 380         let sema = Semantics::new(db);
 381
 382         let original_file = sema.parse(file_id);
 383
 384         // Insert a fake ident to get a valid parse tree. We will use this file
 385         // to determine context, though the original_file will be used for
 386         // actual completion.
 387         let file_with_fake_ident = {
 388             let parse = db.parse(file_id);
 389             let edit = Indel::insert(offset, COMPLETION_MARKER.to_string());
 390             parse.reparse(&edit).tree()
 391         };
 392         let fake_ident_token =
 393             file_with_fake_ident.syntax().token_at_offset(offset).right_biased()?;
 394
 395         let original_token = original_file.syntax().token_at_offset(offset).left_biased()?;
 396         let token = sema.descend_into_macros_single(original_token.clone());
 397         let scope = sema.scope_at_offset(&token.parent()?, offset);
 398         let krate = scope.krate();
 399         let module = scope.module();
 400         let mut locals = vec![];
 401         scope.process_all_names(&mut |name, scope| {
 402             if let ScopeDef::Local(local) = scope {
 403                 locals.push((name, local));
 404             }
 405         });
 406
 407         let mut ctx = CompletionContext {
 408             sema,
 409             scope,
 410             db,
 411             config,
 412             position,
 413             original_token,
 414             token,
 415             krate,
 416             module,
 417             expected_name: None,
 418             expected_type: None,
 419             function_def: None,
 420             attr: None,
 421             impl_def: None,
 422             name_syntax: None,
 423             lifetime_ctx: None,
 424             pattern_ctx: None,
 425             completion_location: None,
 426             prev_sibling: None,
 427             fake_attribute_under_caret: None,
 428             previous_token: None,
 429             path_context: None,
 430             locals,
 431             incomplete_let: false,
 432             no_completion_required: false,
 433         };
 434         ctx.expand_and_fill(
 435             original_file.syntax().clone(),
 436             file_with_fake_ident.syntax().clone(),
 437             offset,
 438             fake_ident_token,
 439         );
 440         Some(ctx)
 441     }
 442
 443     /// Do the attribute expansion at the current cursor position for both original file and fake file
 444     /// as long as possible. As soon as one of the two expansions fail we stop to stay in sync.
 445     fn expand_and_fill(
 446         &mut self,
 447         mut original_file: SyntaxNode,
 448         mut speculative_file: SyntaxNode,
 449         mut offset: TextSize,
 450         mut fake_ident_token: SyntaxToken,
 451     ) {
 452         let _p = profile::span("CompletionContext::expand_and_fill");
 453         'expansion: loop {
 454             let parent_item =
 455                 |item: &ast::Item| item.syntax().ancestors().skip(1).find_map(ast::Item::cast);
 456             let ancestor_items = iter::successors(
 457                 Option::zip(
 458                     find_node_at_offset::<ast::Item>(&original_file, offset),
 459                     find_node_at_offset::<ast::Item>(&speculative_file, offset),
 460                 ),
 461                 |(a, b)| parent_item(a).zip(parent_item(b)),
 462             );
 463             for (actual_item, item_with_fake_ident) in ancestor_items {
 464                 match (
 465                     self.sema.expand_attr_macro(&actual_item),
 466                     self.sema.speculative_expand_attr_macro(
 467                         &actual_item,
 468                         &item_with_fake_ident,
 469                         fake_ident_token.clone(),
 470                     ),
 471                 ) {
 472                     // maybe parent items have attributes
 473                     (None, None) => (),
 474                     // successful expansions
 475                     (Some(actual_expansion), Some((fake_expansion, fake_mapped_token))) => {
 476                         let new_offset = fake_mapped_token.text_range().start();
 477                         if new_offset > actual_expansion.text_range().end() {
 478                             break 'expansion;
 479                         }
 480                         original_file = actual_expansion;
 481                         speculative_file = fake_expansion;
 482                         fake_ident_token = fake_mapped_token;
 483                         offset = new_offset;
 484                         continue 'expansion;
 485                     }
 486                     // exactly one expansion failed, inconsistent state so stop expanding completely
 487                     _ => break 'expansion,
 488                 }
 489             }
 490
 491             // Expand fn-like macro calls
 492             if let (Some(actual_macro_call), Some(macro_call_with_fake_ident)) = (
 493                 find_node_at_offset::<ast::MacroCall>(&original_file, offset),
 494                 find_node_at_offset::<ast::MacroCall>(&speculative_file, offset),
 495             ) {
 496                 let mac_call_path0 = actual_macro_call.path().as_ref().map(|s| s.syntax().text());
 497                 let mac_call_path1 =
 498                     macro_call_with_fake_ident.path().as_ref().map(|s| s.syntax().text());
 499                 if mac_call_path0 != mac_call_path1 {
 500                     break;
 501                 }
 502                 let speculative_args = match macro_call_with_fake_ident.token_tree() {
 503                     Some(tt) => tt,
 504                     None => break,
 505                 };
 506
 507                 match (
 508                     self.sema.expand(&actual_macro_call),
 509                     self.sema.speculative_expand(
 510                         &actual_macro_call,
 511                         &speculative_args,
 512                         fake_ident_token.clone(),
 513                     ),
 514                 ) {
 515                     // successful expansions
 516                     (Some(actual_expansion), Some((fake_expansion, fake_mapped_token))) => {
 517                         let new_offset = fake_mapped_token.text_range().start();
 518                         if new_offset > actual_expansion.text_range().end() {
 519                             break;
 520                         }
 521                         original_file = actual_expansion;
 522                         speculative_file = fake_expansion;
 523                         fake_ident_token = fake_mapped_token;
 524                         offset = new_offset;
 525                         continue;
 526                     }
 527                     _ => break,
 528                 }
 529             }
 530
 531             break;
 532         }
 533
 534         self.fill(&original_file, speculative_file, offset);
 535     }
 536
 537     fn expected_type_and_name(&self) -> (Option<Type>, Option<NameOrNameRef>) {
 538         let mut node = match self.token.parent() {
 539             Some(it) => it,
 540             None => return (None, None),
 541         };
 542         loop {
 543             break match_ast! {
 544                 match node {
 545                     ast::LetStmt(it) => {
 546                         cov_mark::hit!(expected_type_let_with_leading_char);
 547                         cov_mark::hit!(expected_type_let_without_leading_char);
 548                         let ty = it.pat()
 549                             .and_then(|pat| self.sema.type_of_pat(&pat))
 550                             .or_else(|| it.initializer().and_then(|it| self.sema.type_of_expr(&it)))
 551                             .map(TypeInfo::original);
 552                         let name = match it.pat() {
 553                             Some(ast::Pat::IdentPat(ident)) => ident.name().map(NameOrNameRef::Name),
 554                             Some(_) | None => None,
 555                         };
 556
 557                         (ty, name)
 558                     },
 559                     ast::ArgList(_) => {
 560                         cov_mark::hit!(expected_type_fn_param);
 561                         ActiveParameter::at_token(
 562                             &self.sema,
 563                             self.token.clone(),
 564                         ).map(|ap| {
 565                             let name = ap.ident().map(NameOrNameRef::Name);
 566                             let ty = if has_ref(&self.token) {
 567                                 cov_mark::hit!(expected_type_fn_param_ref);
 568                                 ap.ty.remove_ref()
 569                             } else {
 570                                 Some(ap.ty)
 571                             };
 572                             (ty, name)
 573                         })
 574                         .unwrap_or((None, None))
 575                     },
 576                     ast::RecordExprFieldList(it) => {
 577                         // wouldn't try {} be nice...
 578                         (|| {
 579                             if self.token.kind() == T![..]
 580                                 || self.token.prev_token().map(|t| t.kind()) == Some(T![..])
 581                             {
 582                                 cov_mark::hit!(expected_type_struct_func_update);
 583                                 let record_expr = it.syntax().parent().and_then(ast::RecordExpr::cast)?;
 584                                 let ty = self.sema.type_of_expr(&record_expr.into())?;
 585                                 Some((
 586                                     Some(ty.original),
 587                                     None
 588                                 ))
 589                             } else {
 590                                 cov_mark::hit!(expected_type_struct_field_without_leading_char);
 591                                 let expr_field = self.token.prev_sibling_or_token()?
 592                                     .into_node()
 593                                     .and_then(ast::RecordExprField::cast)?;
 594                                 let (_, _, ty) = self.sema.resolve_record_field(&expr_field)?;
 595                                 Some((
 596                                     Some(ty),
 597                                     expr_field.field_name().map(NameOrNameRef::NameRef),
 598                                 ))
 599                             }
 600                         })().unwrap_or((None, None))
 601                     },
 602                     ast::RecordExprField(it) => {
 603                         if let Some(expr) = it.expr() {
 604                             cov_mark::hit!(expected_type_struct_field_with_leading_char);
 605                             (
 606                                 self.sema.type_of_expr(&expr).map(TypeInfo::original),
 607                                 it.field_name().map(NameOrNameRef::NameRef),
 608                             )
 609                         } else {
 610                             cov_mark::hit!(expected_type_struct_field_followed_by_comma);
 611                             let ty = self.sema.resolve_record_field(&it)
 612                                 .map(|(_, _, ty)| ty);
 613                             (
 614                                 ty,
 615                                 it.field_name().map(NameOrNameRef::NameRef),
 616                             )
 617                         }
 618                     },
 619                     ast::MatchExpr(it) => {
 620                         cov_mark::hit!(expected_type_match_arm_without_leading_char);
 621                         let ty = it.expr().and_then(|e| self.sema.type_of_expr(&e)).map(TypeInfo::original);
 622                         (ty, None)
 623                     },
 624                     ast::IfExpr(it) => {
 625                         cov_mark::hit!(expected_type_if_let_without_leading_char);
 626                         let ty = it.condition()
 627                             .and_then(|cond| cond.expr())
 628                             .and_then(|e| self.sema.type_of_expr(&e))
 629                             .map(TypeInfo::original);
 630                         (ty, None)
 631                     },
 632                     ast::IdentPat(it) => {
 633                         cov_mark::hit!(expected_type_if_let_with_leading_char);
 634                         cov_mark::hit!(expected_type_match_arm_with_leading_char);
 635                         let ty = self.sema.type_of_pat(&ast::Pat::from(it)).map(TypeInfo::original);
 636                         (ty, None)
 637                     },
 638                     ast::Fn(it) => {
 639                         cov_mark::hit!(expected_type_fn_ret_with_leading_char);
 640                         cov_mark::hit!(expected_type_fn_ret_without_leading_char);
 641                         let def = self.sema.to_def(&it);
 642                         (def.map(|def| def.ret_type(self.db)), None)
 643                     },
 644                     ast::ClosureExpr(it) => {
 645                         let ty = self.sema.type_of_expr(&it.into());
 646                         ty.and_then(|ty| ty.original.as_callable(self.db))
 647                             .map(|c| (Some(c.return_type()), None))
 648                             .unwrap_or((None, None))
 649                     },
 650                     ast::ParamList(_) => (None, None),
 651                     ast::Stmt(_) => (None, None),
 652                     ast::Item(_) => (None, None),
 653                     _ => {
 654                         match node.parent() {
 655                             Some(n) => {
 656                                 node = n;
 657                                 continue;
 658                             },
 659                             None => (None, None),
 660                         }
 661                     },
 662                 }
 663             };
 664         }
 665     }
 666
 667     fn fill(
 668         &mut self,
 669         original_file: &SyntaxNode,
 670         file_with_fake_ident: SyntaxNode,
 671         offset: TextSize,
 672     ) {
 673         let fake_ident_token = file_with_fake_ident.token_at_offset(offset).right_biased().unwrap();
 674         let syntax_element = NodeOrToken::Token(fake_ident_token);
 675         self.previous_token = previous_token(syntax_element.clone());
 676         self.no_completion_required = {
 677             let inside_impl_trait_block = inside_impl_trait_block(syntax_element.clone());
 678             let fn_is_prev = self.previous_token_is(T![fn]);
 679             let for_is_prev2 = for_is_prev2(syntax_element.clone());
 680             (fn_is_prev && !inside_impl_trait_block) || for_is_prev2
 681         };
 682
 683         self.attr = self
 684             .sema
 685             .token_ancestors_with_macros(self.token.clone())
 686             .take_while(|it| it.kind() != SOURCE_FILE && it.kind() != MODULE)
 687             .find_map(ast::Attr::cast);
 688         self.fake_attribute_under_caret = syntax_element.ancestors().find_map(ast::Attr::cast);
 689
 690         self.incomplete_let =
 691             syntax_element.ancestors().take(6).find_map(ast::LetStmt::cast).map_or(false, |it| {
 692                 it.syntax().text_range().end() == syntax_element.text_range().end()
 693             });
 694
 695         let (expected_type, expected_name) = self.expected_type_and_name();
 696         self.expected_type = expected_type;
 697         self.expected_name = expected_name;
 698
 699         let name_like = match find_node_at_offset(&file_with_fake_ident, offset) {
 700             Some(it) => it,
 701             None => return,
 702         };
 703         self.completion_location =
 704             determine_location(&self.sema, original_file, offset, &name_like);
 705         self.prev_sibling = determine_prev_sibling(&name_like);
 706         self.name_syntax =
 707             find_node_at_offset(original_file, name_like.syntax().text_range().start());
 708         self.impl_def = self
 709             .sema
 710             .token_ancestors_with_macros(self.token.clone())
 711             .take_while(|it| it.kind() != SOURCE_FILE && it.kind() != MODULE)
 712             .find_map(ast::Impl::cast);
 713         self.function_def = self
 714             .sema
 715             .token_ancestors_with_macros(self.token.clone())
 716             .take_while(|it| it.kind() != SOURCE_FILE && it.kind() != MODULE)
 717             .find_map(ast::Fn::cast);
 718         match name_like {
 719             ast::NameLike::Lifetime(lifetime) => {
 720                 self.lifetime_ctx =
 721                     Self::classify_lifetime(&self.sema, original_file, lifetime, offset);
 722             }
 723             ast::NameLike::NameRef(name_ref) => {
 724                 if let Some((path_ctx, pat_ctx)) =
 725                     Self::classify_name_ref(&self.sema, original_file, name_ref)
 726                 {
 727                     self.path_context = Some(path_ctx);
 728                     self.pattern_ctx = pat_ctx;
 729                 }
 730             }
 731             ast::NameLike::Name(name) => {
 732                 self.pattern_ctx = Self::classify_name(&self.sema, original_file, name);
 733             }
 734         }
 735     }
 736
 737     fn classify_lifetime(
 738         sema: &Semantics<RootDatabase>,
 739         original_file: &SyntaxNode,
 740         lifetime: ast::Lifetime,
 741         offset: TextSize,
 742     ) -> Option<LifetimeContext> {
 743         let parent = lifetime.syntax().parent()?;
 744         if parent.kind() == ERROR {
 745             return None;
 746         }
 747
 748         Some(match_ast! {
 749             match parent {
 750                 ast::LifetimeParam(_) => LifetimeContext::LifetimeParam(sema.find_node_at_offset_with_macros(original_file, offset)),
 751                 ast::BreakExpr(_) => LifetimeContext::LabelRef,
 752                 ast::ContinueExpr(_) => LifetimeContext::LabelRef,
 753                 ast::Label(_) => LifetimeContext::LabelDef,
 754                 _ => LifetimeContext::Lifetime,
 755             }
 756         })
 757     }
 758
 759     fn classify_name(
 760         _sema: &Semantics<RootDatabase>,
 761         original_file: &SyntaxNode,
 762         name: ast::Name,
 763     ) -> Option<PatternContext> {
 764         let bind_pat = name.syntax().parent().and_then(ast::IdentPat::cast)?;
 765         let is_name_in_field_pat = bind_pat
 766             .syntax()
 767             .parent()
 768             .and_then(ast::RecordPatField::cast)
 769             .map_or(false, |pat_field| pat_field.name_ref().is_none());
 770         if is_name_in_field_pat {
 771             return None;
 772         }
 773         if !bind_pat.is_simple_ident() {
 774             return None;
 775         }
 776         Some(pattern_context_for(original_file, bind_pat.into()))
 777     }
 778
 779     fn classify_name_ref(
 780         _sema: &Semantics<RootDatabase>,
 781         original_file: &SyntaxNode,
 782         name_ref: ast::NameRef,
 783     ) -> Option<(PathCompletionContext, Option<PatternContext>)> {
 784         let parent = name_ref.syntax().parent()?;
 785         let segment = ast::PathSegment::cast(parent)?;
 786         let path = segment.parent_path();
 787
 788         let mut path_ctx = PathCompletionContext {
 789             has_call_parens: false,
 790             is_trivial_path: false,
 791             qualifier: None,
 792             parent: None,
 793             has_type_args: false,
 794             can_be_stmt: false,
 795             in_loop_body: false,
 796             use_tree_parent: false,
 797             kind: None,
 798         };
 799         let mut pat_ctx = None;
 800         path_ctx.in_loop_body = is_in_loop_body(name_ref.syntax());
 801
 802         path_ctx.kind  = path.syntax().ancestors().find_map(|it| {
 803             match_ast! {
 804                 match it {
 805                     ast::PathType(_) => Some(PathKind::Type),
 806                     ast::PathExpr(it) => {
 807                         path_ctx.has_call_parens = it.syntax().parent().map_or(false, |it| ast::CallExpr::can_cast(it.kind()));
 808                         Some(PathKind::Expr)
 809                     },
 810                     ast::TupleStructPat(it) => {
 811                         path_ctx.has_call_parens = true;
 812                         pat_ctx = Some(pattern_context_for(original_file, it.into()));
 813                         Some(PathKind::Pat)
 814                     },
 815                     ast::RecordPat(it) => {
 816                         pat_ctx = Some(pattern_context_for(original_file, it.into()));
 817                         Some(PathKind::Pat)
 818                     },
 819                     ast::PathPat(it) => {
 820                         pat_ctx = Some(pattern_context_for(original_file, it.into()));
 821                         Some(PathKind::Pat)
 822                     },
 823                     ast::MacroCall(it) => it.excl_token().and(Some(PathKind::Mac)),
 824                     ast::Meta(_) => Some(PathKind::Attr),
 825                     ast::Visibility(it) => Some(PathKind::Vis { has_in_token: it.in_token().is_some() }),
 826                     ast::UseTree(_) => Some(PathKind::Use),
 827                     _ => None,
 828                 }
 829             }
 830         });
 831         path_ctx.has_type_args = segment.generic_arg_list().is_some();
 832
 833         if let Some((path, use_tree_parent)) = path_or_use_tree_qualifier(&path) {
 834             path_ctx.use_tree_parent = use_tree_parent;
 835             path_ctx.qualifier = path
 836                 .segment()
 837                 .and_then(|it| find_node_in_file(original_file, &it))
 838                 .map(|it| it.parent_path());
 839             return Some((path_ctx, pat_ctx));
 840         }
 841
 842         if let Some(segment) = path.segment() {
 843             if segment.coloncolon_token().is_some() {
 844                 return Some((path_ctx, pat_ctx));
 845             }
 846         }
 847
 848         path_ctx.is_trivial_path = true;
 849
 850         // Find either enclosing expr statement (thing with `;`) or a
 851         // block. If block, check that we are the last expr.
 852         path_ctx.can_be_stmt = name_ref
 853             .syntax()
 854             .ancestors()
 855             .find_map(|node| {
 856                 if let Some(stmt) = ast::ExprStmt::cast(node.clone()) {
 857                     return Some(stmt.syntax().text_range() == name_ref.syntax().text_range());
 858                 }
 859                 if let Some(stmt_list) = ast::StmtList::cast(node) {
 860                     return Some(
 861                         stmt_list.tail_expr().map(|e| e.syntax().text_range())
 862                             == Some(name_ref.syntax().text_range()),
 863                     );
 864                 }
 865                 None
 866             })
 867             .unwrap_or(false);
 868         Some((path_ctx, pat_ctx))
 869     }
 870 }
 871
 872 fn pattern_context_for(original_file: &SyntaxNode, pat: ast::Pat) -> PatternContext {
 873     let mut is_param = None;
 874     let (refutability, has_type_ascription) =
 875     pat
 876         .syntax()
 877         .ancestors()
 878         .skip_while(|it| ast::Pat::can_cast(it.kind()))
 879         .next()
 880         .map_or((PatternRefutability::Irrefutable, false), |node| {
 881             let refutability = match_ast! {
 882                 match node {
 883                     ast::LetStmt(let_) => return (PatternRefutability::Irrefutable, let_.ty().is_some()),
 884                     ast::Param(param) => {
 885                         let has_type_ascription = param.ty().is_some();
 886                         is_param = (|| {
 887                             let fake_param_list = param.syntax().parent().and_then(ast::ParamList::cast)?;
 888                             let param_list = find_node_in_file_compensated(original_file, &fake_param_list)?;
 889                             let param_list_owner = param_list.syntax().parent()?;
 890                             let kind = match_ast! {
 891                                 match param_list_owner {
 892                                     ast::ClosureExpr(closure) => ParamKind::Closure(closure),
 893                                     ast::Fn(fn_) => ParamKind::Function(fn_),
 894                                     _ => return None,
 895                                 }
 896                             };
 897                             Some((param_list, param, kind))
 898                         })();
 899                         return (PatternRefutability::Irrefutable, has_type_ascription)
 900                     },
 901                     ast::MatchArm(_) => PatternRefutability::Refutable,
 902                     ast::Condition(_) => PatternRefutability::Refutable,
 903                     ast::ForExpr(_) => PatternRefutability::Irrefutable,
 904                     _ => PatternRefutability::Irrefutable,
 905                 }
 906             };
 907             (refutability, false)
 908         });
 909     PatternContext { refutability, param_ctx: is_param, has_type_ascription }
 910 }
 911
 912 fn find_node_in_file<N: AstNode>(syntax: &SyntaxNode, node: &N) -> Option<N> {
 913     let syntax_range = syntax.text_range();
 914     let range = node.syntax().text_range();
 915     let intersection = range.intersect(syntax_range)?;
 916     syntax.covering_element(intersection).ancestors().find_map(N::cast)
 917 }
 918
 919 /// Compensates for the offset introduced by the fake ident
 920 /// This is wrong if `node` comes before the insertion point! Use `find_node_in_file` instead.
 921 fn find_node_in_file_compensated<N: AstNode>(syntax: &SyntaxNode, node: &N) -> Option<N> {
 922     let syntax_range = syntax.text_range();
 923     let range = node.syntax().text_range();
 924     let end = range.end().checked_sub(TextSize::try_from(COMPLETION_MARKER.len()).ok()?)?;
 925     if end < range.start() {
 926         return None;
 927     }
 928     let range = TextRange::new(range.start(), end);
 929     // our inserted ident could cause `range` to be go outside of the original syntax, so cap it
 930     let intersection = range.intersect(syntax_range)?;
 931     syntax.covering_element(intersection).ancestors().find_map(N::cast)
 932 }
 933
 934 fn path_or_use_tree_qualifier(path: &ast::Path) -> Option<(ast::Path, bool)> {
 935     if let Some(qual) = path.qualifier() {
 936         return Some((qual, false));
 937     }
 938     let use_tree_list = path.syntax().ancestors().find_map(ast::UseTreeList::cast)?;
 939     let use_tree = use_tree_list.syntax().parent().and_then(ast::UseTree::cast)?;
 940     use_tree.path().zip(Some(true))
 941 }
 942
 943 fn has_ref(token: &SyntaxToken) -> bool {
 944     let mut token = token.clone();
 945     for skip in [IDENT, WHITESPACE, T![mut]] {
 946         if token.kind() == skip {
 947             token = match token.prev_token() {
 948                 Some(it) => it,
 949                 None => return false,
 950             }
 951         }
 952     }
 953     token.kind() == T![&]
 954 }
 955
 956 const OP_TRAIT_LANG_NAMES: &[&str] = &[
 957     "add_assign",
 958     "add",
 959     "bitand_assign",
 960     "bitand",
 961     "bitor_assign",
 962     "bitor",
 963     "bitxor_assign",
 964     "bitxor",
 965     "deref_mut",
 966     "deref",
 967     "div_assign",
 968     "div",
 969     "eq",
 970     "fn_mut",
 971     "fn_once",
 972     "fn",
 973     "index_mut",
 974     "index",
 975     "mul_assign",
 976     "mul",
 977     "neg",
 978     "not",
 979     "partial_ord",
 980     "rem_assign",
 981     "rem",
 982     "shl_assign",
 983     "shl",
 984     "shr_assign",
 985     "shr",
 986     "sub",
 987 ];
 988 #[cfg(test)]
 989 mod tests {
 990     use expect_test::{expect, Expect};
 991     use hir::HirDisplay;
 992
 993     use crate::tests::{position, TEST_CONFIG};
 994
 995     use super::CompletionContext;
 996
 997     fn check_expected_type_and_name(ra_fixture: &str, expect: Expect) {
 998         let (db, pos) = position(ra_fixture);
 999         let config = TEST_CONFIG;
1000         let completion_context = CompletionContext::new(&db, pos, &config).unwrap();
1001
1002         let ty = completion_context
1003             .expected_type
1004             .map(|t| t.display_test(&db).to_string())
1005             .unwrap_or("?".to_owned());
1006
1007         let name = completion_context
1008             .expected_name
1009             .map_or_else(|| "?".to_owned(), |name| name.to_string());
1010
1011         expect.assert_eq(&format!("ty: {}, name: {}", ty, name));
1012     }
1013
1014     #[test]
1015     fn expected_type_let_without_leading_char() {
1016         cov_mark::check!(expected_type_let_without_leading_char);
1017         check_expected_type_and_name(
1018             r#"
1019 fn foo() {
1020     let x: u32 = $0;
1021 }
1022 "#,
1023             expect![[r#"ty: u32, name: x"#]],
1024         );
1025     }
1026
1027     #[test]
1028     fn expected_type_let_with_leading_char() {
1029         cov_mark::check!(expected_type_let_with_leading_char);
1030         check_expected_type_and_name(
1031             r#"
1032 fn foo() {
1033     let x: u32 = c$0;
1034 }
1035 "#,
1036             expect![[r#"ty: u32, name: x"#]],
1037         );
1038     }
1039
1040     #[test]
1041     fn expected_type_let_pat() {
1042         check_expected_type_and_name(
1043             r#"
1044 fn foo() {
1045     let x$0 = 0u32;
1046 }
1047 "#,
1048             expect![[r#"ty: u32, name: ?"#]],
1049         );
1050         check_expected_type_and_name(
1051             r#"
1052 fn foo() {
1053     let $0 = 0u32;
1054 }
1055 "#,
1056             expect![[r#"ty: u32, name: ?"#]],
1057         );
1058     }
1059
1060     #[test]
1061     fn expected_type_fn_param() {
1062         cov_mark::check!(expected_type_fn_param);
1063         check_expected_type_and_name(
1064             r#"
1065 fn foo() { bar($0); }
1066 fn bar(x: u32) {}
1067 "#,
1068             expect![[r#"ty: u32, name: x"#]],
1069         );
1070         check_expected_type_and_name(
1071             r#"
1072 fn foo() { bar(c$0); }
1073 fn bar(x: u32) {}
1074 "#,
1075             expect![[r#"ty: u32, name: x"#]],
1076         );
1077     }
1078
1079     #[test]
1080     fn expected_type_fn_param_ref() {
1081         cov_mark::check!(expected_type_fn_param_ref);
1082         check_expected_type_and_name(
1083             r#"
1084 fn foo() { bar(&$0); }
1085 fn bar(x: &u32) {}
1086 "#,
1087             expect![[r#"ty: u32, name: x"#]],
1088         );
1089         check_expected_type_and_name(
1090             r#"
1091 fn foo() { bar(&mut $0); }
1092 fn bar(x: &mut u32) {}
1093 "#,
1094             expect![[r#"ty: u32, name: x"#]],
1095         );
1096         check_expected_type_and_name(
1097             r#"
1098 fn foo() { bar(& c$0); }
1099 fn bar(x: &u32) {}
1100         "#,
1101             expect![[r#"ty: u32, name: x"#]],
1102         );
1103         check_expected_type_and_name(
1104             r#"
1105 fn foo() { bar(&mut c$0); }
1106 fn bar(x: &mut u32) {}
1107 "#,
1108             expect![[r#"ty: u32, name: x"#]],
1109         );
1110         check_expected_type_and_name(
1111             r#"
1112 fn foo() { bar(&c$0); }
1113 fn bar(x: &u32) {}
1114         "#,
1115             expect![[r#"ty: u32, name: x"#]],
1116         );
1117     }
1118
1119     #[test]
1120     fn expected_type_struct_field_without_leading_char() {
1121         cov_mark::check!(expected_type_struct_field_without_leading_char);
1122         check_expected_type_and_name(
1123             r#"
1124 struct Foo { a: u32 }
1125 fn foo() {
1126     Foo { a: $0 };
1127 }
1128 "#,
1129             expect![[r#"ty: u32, name: a"#]],
1130         )
1131     }
1132
1133     #[test]
1134     fn expected_type_struct_field_followed_by_comma() {
1135         cov_mark::check!(expected_type_struct_field_followed_by_comma);
1136         check_expected_type_and_name(
1137             r#"
1138 struct Foo { a: u32 }
1139 fn foo() {
1140     Foo { a: $0, };
1141 }
1142 "#,
1143             expect![[r#"ty: u32, name: a"#]],
1144         )
1145     }
1146
1147     #[test]
1148     fn expected_type_generic_struct_field() {
1149         check_expected_type_and_name(
1150             r#"
1151 struct Foo<T> { a: T }
1152 fn foo() -> Foo<u32> {
1153     Foo { a: $0 }
1154 }
1155 "#,
1156             expect![[r#"ty: u32, name: a"#]],
1157         )
1158     }
1159
1160     #[test]
1161     fn expected_type_struct_field_with_leading_char() {
1162         cov_mark::check!(expected_type_struct_field_with_leading_char);
1163         check_expected_type_and_name(
1164             r#"
1165 struct Foo { a: u32 }
1166 fn foo() {
1167     Foo { a: c$0 };
1168 }
1169 "#,
1170             expect![[r#"ty: u32, name: a"#]],
1171         );
1172     }
1173
1174     #[test]
1175     fn expected_type_match_arm_without_leading_char() {
1176         cov_mark::check!(expected_type_match_arm_without_leading_char);
1177         check_expected_type_and_name(
1178             r#"
1179 enum E { X }
1180 fn foo() {
1181    match E::X { $0 }
1182 }
1183 "#,
1184             expect![[r#"ty: E, name: ?"#]],
1185         );
1186     }
1187
1188     #[test]
1189     fn expected_type_match_arm_with_leading_char() {
1190         cov_mark::check!(expected_type_match_arm_with_leading_char);
1191         check_expected_type_and_name(
1192             r#"
1193 enum E { X }
1194 fn foo() {
1195    match E::X { c$0 }
1196 }
1197 "#,
1198             expect![[r#"ty: E, name: ?"#]],
1199         );
1200     }
1201
1202     #[test]
1203     fn expected_type_if_let_without_leading_char() {
1204         cov_mark::check!(expected_type_if_let_without_leading_char);
1205         check_expected_type_and_name(
1206             r#"
1207 enum Foo { Bar, Baz, Quux }
1208
1209 fn foo() {
1210     let f = Foo::Quux;
1211     if let $0 = f { }
1212 }
1213 "#,
1214             expect![[r#"ty: Foo, name: ?"#]],
1215         )
1216     }
1217
1218     #[test]
1219     fn expected_type_if_let_with_leading_char() {
1220         cov_mark::check!(expected_type_if_let_with_leading_char);
1221         check_expected_type_and_name(
1222             r#"
1223 enum Foo { Bar, Baz, Quux }
1224
1225 fn foo() {
1226     let f = Foo::Quux;
1227     if let c$0 = f { }
1228 }
1229 "#,
1230             expect![[r#"ty: Foo, name: ?"#]],
1231         )
1232     }
1233
1234     #[test]
1235     fn expected_type_fn_ret_without_leading_char() {
1236         cov_mark::check!(expected_type_fn_ret_without_leading_char);
1237         check_expected_type_and_name(
1238             r#"
1239 fn foo() -> u32 {
1240     $0
1241 }
1242 "#,
1243             expect![[r#"ty: u32, name: ?"#]],
1244         )
1245     }
1246
1247     #[test]
1248     fn expected_type_fn_ret_with_leading_char() {
1249         cov_mark::check!(expected_type_fn_ret_with_leading_char);
1250         check_expected_type_and_name(
1251             r#"
1252 fn foo() -> u32 {
1253     c$0
1254 }
1255 "#,
1256             expect![[r#"ty: u32, name: ?"#]],
1257         )
1258     }
1259
1260     #[test]
1261     fn expected_type_fn_ret_fn_ref_fully_typed() {
1262         check_expected_type_and_name(
1263             r#"
1264 fn foo() -> u32 {
1265     foo$0
1266 }
1267 "#,
1268             expect![[r#"ty: u32, name: ?"#]],
1269         )
1270     }
1271
1272     #[test]
1273     fn expected_type_closure_param_return() {
1274         // FIXME: make this work with `|| $0`
1275         check_expected_type_and_name(
1276             r#"
1277 //- minicore: fn
1278 fn foo() {
1279     bar(|| a$0);
1280 }
1281
1282 fn bar(f: impl FnOnce() -> u32) {}
1283 "#,
1284             expect![[r#"ty: u32, name: ?"#]],
1285         );
1286     }
1287
1288     #[test]
1289     fn expected_type_generic_function() {
1290         check_expected_type_and_name(
1291             r#"
1292 fn foo() {
1293     bar::<u32>($0);
1294 }
1295
1296 fn bar<T>(t: T) {}
1297 "#,
1298             expect![[r#"ty: u32, name: t"#]],
1299         );
1300     }
1301
1302     #[test]
1303     fn expected_type_generic_method() {
1304         check_expected_type_and_name(
1305             r#"
1306 fn foo() {
1307     S(1u32).bar($0);
1308 }
1309
1310 struct S<T>(T);
1311 impl<T> S<T> {
1312     fn bar(self, t: T) {}
1313 }
1314 "#,
1315             expect![[r#"ty: u32, name: t"#]],
1316         );
1317     }
1318
1319     #[test]
1320     fn expected_type_functional_update() {
1321         cov_mark::check!(expected_type_struct_func_update);
1322         check_expected_type_and_name(
1323             r#"
1324 struct Foo { field: u32 }
1325 fn foo() {
1326     Foo {
1327         ..$0
1328     }
1329 }
1330 "#,
1331             expect![[r#"ty: Foo, name: ?"#]],
1332         );
1333     }
1334
1335     #[test]
1336     fn expected_type_param_pat() {
1337         check_expected_type_and_name(
1338             r#"
1339 struct Foo { field: u32 }
1340 fn foo(a$0: Foo) {}
1341 "#,
1342             expect![[r#"ty: Foo, name: ?"#]],
1343         );
1344         check_expected_type_and_name(
1345             r#"
1346 struct Foo { field: u32 }
1347 fn foo($0: Foo) {}
1348 "#,
1349             // FIXME make this work, currently fails due to pattern recovery eating the `:`
1350             expect![[r#"ty: ?, name: ?"#]],
1351         );
1352     }
1353 }