[CodeCompletion] Migrate CaseStmtBeginning to solver-based

Author: ahoppen

include/swift/IDE/ExprCompletion.h

@@ -31,6 +31,11 @@ class ExprTypeCheckCompletionCallback : public TypeCheckCompletionCallback {
     /// functions is supported.
     bool IsInAsyncContext;
 
+    /// If unresolved member lookup is enabled in the completion callback,
+    /// the type that the unresolved member lookup should be performed on,
+    /// otherwise a null type.
+    Type UnresolvedMemberBaseType;
+
     /// Types of variables that were determined in the solution that produced
     /// this result. This in particular includes parameters of closures that
     /// were type-checked with the code completion expression.
@@ -54,6 +59,11 @@ class ExprTypeCheckCompletionCallback : public TypeCheckCompletionCallback {
   /// in almost all cases and acceptable results in the other cases.
   SmallVector<Type, 4> ExpectedTypes;
 
+  /// When \c true, unresolved member completions of the expected types are
+  /// also reported when delivering results. Used in places that frequently
+  /// use unresolved members such as enum cases.
+  bool AddUnresolvedMemberCompletions;
+
   SmallVector<Result, 4> Results;
 
   /// Adds the given type to \c ExpectedTypes unless \c ExpectedTypes already
@@ -62,17 +72,22 @@ class ExprTypeCheckCompletionCallback : public TypeCheckCompletionCallback {
 
   /// Adds the result with the given parameters to \c Results unless \c Results
   /// already contains an entry with exactly the same values.
+  /// If \c AddUnresolvedMemberCompletions is false, the
+  /// \p UnresolvedMemberBaseType is ignored.
   void addResult(
       bool IsImplicitSingleExpressionReturn, bool IsInAsyncContext,
+      Type UnresolvedMemberBaseType,
       llvm::SmallDenseMap<const VarDecl *, Type> SolutionSpecificVarTypes);
 
   void sawSolutionImpl(const constraints::Solution &solution) override;
 
 public:
   /// \param DC The decl context in which the \p CompletionExpr occurs.
   ExprTypeCheckCompletionCallback(CodeCompletionExpr *CompletionExpr,
-                                  DeclContext *DC)
-      : CompletionExpr(CompletionExpr), DC(DC) {}
+                                  DeclContext *DC,
+                                  bool AddUnresolvedMemberCompletions)
+      : CompletionExpr(CompletionExpr), DC(DC),
+        AddUnresolvedMemberCompletions(AddUnresolvedMemberCompletions) {}
 
   /// \param CCLoc The location of the code completion token.
   void deliverResults(SourceLoc CCLoc,

lib/IDE/CodeCompletion.cpp

@@ -1405,13 +1405,16 @@ bool CodeCompletionCallbacksImpl::trySolverCompletion(bool MaybeFuncBody) {
     return true;
   }
   case CompletionKind::AccessorBeginning:
+  case CompletionKind::CaseStmtBeginning:
   case CompletionKind::ForEachSequence:
   case CompletionKind::PostfixExprBeginning:
   case CompletionKind::StmtOrExpr: {
     assert(CurDeclContext);
 
-    ExprTypeCheckCompletionCallback Lookup(CodeCompleteTokenExpr,
-                                           CurDeclContext);
+    bool AddUnresolvedMemberCompletions =
+        (Kind == CompletionKind::CaseStmtBeginning);
+    ExprTypeCheckCompletionCallback Lookup(
+        CodeCompleteTokenExpr, CurDeclContext, AddUnresolvedMemberCompletions);
     if (CodeCompleteTokenExpr) {
       // 'CodeCompletionTokenExpr == nullptr' happens when completing e.g.
       //   var x: Int {
@@ -1583,6 +1586,7 @@ void CodeCompletionCallbacksImpl::doneParsing() {
   case CompletionKind::PostfixExprBeginning:
   case CompletionKind::AfterPoundExpr:
   case CompletionKind::AccessorBeginning:
+  case CompletionKind::CaseStmtBeginning:
     llvm_unreachable("should be already handled");
     return;
 
@@ -1681,16 +1685,6 @@ void CodeCompletionCallbacksImpl::doneParsing() {
     break;
   }
 
-  case CompletionKind::CaseStmtBeginning: {
-    ExprContextInfo ContextInfo(CurDeclContext, CodeCompleteTokenExpr);
-    Lookup.setExpectedTypes(ContextInfo.getPossibleTypes(),
-                            ContextInfo.isImplicitSingleExpressionReturn());
-    Lookup.setIdealExpectedType(CodeCompleteTokenExpr->getType());
-    Lookup.getUnresolvedMemberCompletions(ContextInfo.getPossibleTypes());
-    DoPostfixExprBeginning();
-    break;
-  }
-
   case CompletionKind::NominalMemberBeginning: {
     CompletionOverrideLookup OverrideLookup(CompletionContext.getResultSink(),
                                             P.Context, CurDeclContext,

lib/IDE/CompletionLookup.cpp

@@ -2683,6 +2683,8 @@ void CompletionLookup::getUnresolvedMemberCompletions(Type T) {
   if (!T->mayHaveMembers())
     return;
 
+  NeedLeadingDot = !HaveDot;
+
   if (auto objT = T->getOptionalObjectType()) {
     // Add 'nil' keyword with erasing '.' instruction.
     unsigned bytesToErase = 0;

lib/IDE/ExprCompletion.cpp

@@ -42,6 +42,8 @@ bool ExprTypeCheckCompletionCallback::Result::operator==(
   return IsImplicitSingleExpressionReturn ==
              Other.IsImplicitSingleExpressionReturn &&
          IsInAsyncContext == Other.IsInAsyncContext &&
+         nullableTypesEqual(UnresolvedMemberBaseType,
+                            Other.UnresolvedMemberBaseType) &&
          solutionSpecificVarTypesEqual(SolutionSpecificVarTypes,
                                        Other.SolutionSpecificVarTypes);
 }
@@ -58,9 +60,13 @@ void ExprTypeCheckCompletionCallback::addExpectedType(Type ExpectedType) {
 
 void ExprTypeCheckCompletionCallback::addResult(
     bool IsImplicitSingleExpressionReturn, bool IsInAsyncContext,
+    Type UnresolvedMemberBaseType,
     llvm::SmallDenseMap<const VarDecl *, Type> SolutionSpecificVarTypes) {
+  if (!AddUnresolvedMemberCompletions) {
+    UnresolvedMemberBaseType = Type();
+  }
   Result NewResult = {IsImplicitSingleExpressionReturn, IsInAsyncContext,
-                      SolutionSpecificVarTypes};
+                      UnresolvedMemberBaseType, SolutionSpecificVarTypes};
   if (llvm::is_contained(Results, NewResult)) {
     return;
   }
@@ -80,10 +86,12 @@ void ExprTypeCheckCompletionCallback::sawSolutionImpl(
   llvm::SmallDenseMap<const VarDecl *, Type> SolutionSpecificVarTypes;
   getSolutionSpecificVarTypes(S, SolutionSpecificVarTypes);
 
-  addResult(ImplicitReturn, IsAsync, SolutionSpecificVarTypes);
+  addResult(ImplicitReturn, IsAsync, ExpectedTy, SolutionSpecificVarTypes);
   addExpectedType(ExpectedTy);
 
   if (auto PatternMatchType = getPatternMatchType(S, CompletionExpr)) {
+    addResult(ImplicitReturn, IsAsync, PatternMatchType,
+              SolutionSpecificVarTypes);
     addExpectedType(PatternMatchType);
   }
 }
@@ -104,6 +112,9 @@ void ExprTypeCheckCompletionCallback::deliverResults(
 
     Lookup.getValueCompletionsInDeclContext(CCLoc);
     Lookup.getSelfTypeCompletionInDeclContext(CCLoc, /*isForDeclResult=*/false);
+    if (Result.UnresolvedMemberBaseType) {
+      Lookup.getUnresolvedMemberCompletions(Result.UnresolvedMemberBaseType);
+    }
   }
 
   deliverCompletionResults(CompletionCtx, Lookup, DC, Consumer);

test/IDE/complete_enum_elements.swift

@@ -14,9 +14,9 @@ enum FooEnum: CaseIterable {
 }
 
 // FOO_ENUM_TYPE_CONTEXT: Begin completions
-// FOO_ENUM_TYPE_CONTEXT-DAG: Decl[EnumElement]/CurrNominal/Flair[ExprSpecific]/TypeRelation[Identical]: .Foo1[#FooEnum#]{{; name=.+$}}
-// FOO_ENUM_TYPE_CONTEXT-DAG: Decl[EnumElement]/CurrNominal/Flair[ExprSpecific]/TypeRelation[Identical]: .Foo2[#FooEnum#]{{; name=.+$}}
-// FOO_ENUM_TYPE_CONTEXT-DAG: Decl[StaticVar]/CurrNominal/Flair[ExprSpecific]/TypeRelation[Identical]: .alias1[#FooEnum#]; name=alias1
+// FOO_ENUM_TYPE_CONTEXT-DAG: Decl[EnumElement]/CurrNominal/TypeRelation[Identical]: .Foo1[#FooEnum#]{{; name=.+$}}
+// FOO_ENUM_TYPE_CONTEXT-DAG: Decl[EnumElement]/CurrNominal/TypeRelation[Identical]: .Foo2[#FooEnum#]{{; name=.+$}}
+// FOO_ENUM_TYPE_CONTEXT-DAG: Decl[StaticVar]/CurrNominal/TypeRelation[Identical]: .alias1[#FooEnum#]; name=alias1
 // FOO_ENUM_TYPE_CONTEXT: End completions
 
 // FOO_ENUM_NO_DOT: Begin completions
@@ -202,8 +202,8 @@ enum QuxEnum : Int {
 }
 
 // QUX_ENUM_TYPE_CONTEXT: Begin completions
-// QUX_ENUM_TYPE_CONTEXT-DAG: Decl[EnumElement]/CurrNominal/Flair[ExprSpecific]/TypeRelation[Identical]: .Qux1[#QuxEnum#]{{; name=.+$}}
-// QUX_ENUM_TYPE_CONTEXT-DAG: Decl[EnumElement]/CurrNominal/Flair[ExprSpecific]/TypeRelation[Identical]: .Qux2[#QuxEnum#]{{; name=.+$}}
+// QUX_ENUM_TYPE_CONTEXT-DAG: Decl[EnumElement]/CurrNominal/TypeRelation[Identical]: .Qux1[#QuxEnum#]{{; name=.+$}}
+// QUX_ENUM_TYPE_CONTEXT-DAG: Decl[EnumElement]/CurrNominal/TypeRelation[Identical]: .Qux2[#QuxEnum#]{{; name=.+$}}
 // QUX_ENUM_TYPE_CONTEXT: End completions
 
 // QUX_ENUM_NO_DOT: Begin completions, 7 items