[CodeComplete] Propagate preferred type for function arguments in more cases

Summary:
See the added test for some new cases.
This change also removes special code completion calls inside the
ParseExpressionList function now that we properly propagate expected
type to the function responsible for parsing elements of the expression list
(ParseAssignmentExpression).

Reviewers: kadircet

Reviewed By: kadircet

Subscribers: xbolva00, jdoerfert, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D58541

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@354864 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 72 insertions, 89 deletions

diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 882972d428..84d79d9a47 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -2332,25 +2332,27 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
 
     InitializerScopeRAII InitScope(*this, D, ThisDecl);
 
-    llvm::function_ref<void()> ExprListCompleter;
     auto ThisVarDecl = dyn_cast_or_null<VarDecl>(ThisDecl);
-    auto ConstructorCompleter = [&, ThisVarDecl] {
+    auto RunSignatureHelp = [&]() {
       QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
           getCurScope(), ThisVarDecl->getType()->getCanonicalTypeInternal(),
           ThisDecl->getLocation(), Exprs, T.getOpenLocation());
       CalledSignatureHelp = true;
-      Actions.CodeCompleteExpression(getCurScope(), PreferredType);
+      return PreferredType;
     };
+    auto SetPreferredType = [&] {
+      PreferredType.enterFunctionArgument(Tok.getLocation(), RunSignatureHelp);
+    };
+
+    llvm::function_ref<void()> ExpressionStarts;
     if (ThisVarDecl) {
       // ParseExpressionList can sometimes succeed even when ThisDecl is not
       // VarDecl. This is an error and it is reported in a call to
       // Actions.ActOnInitializerError(). However, we call
-      // ProduceConstructorSignatureHelp only on VarDecls, falling back to
-      // default completer in other cases.
-      ExprListCompleter = ConstructorCompleter;
+      // ProduceConstructorSignatureHelp only on VarDecls.
+      ExpressionStarts = SetPreferredType;
     }
-
-    if (ParseExpressionList(Exprs, CommaLocs, ExprListCompleter)) {
+    if (ParseExpressionList(Exprs, CommaLocs, ExpressionStarts)) {
       if (ThisVarDecl && PP.isCodeCompletionReached() && !CalledSignatureHelp) {
         Actions.ProduceConstructorSignatureHelp(
             getCurScope(), ThisVarDecl->getType()->getCanonicalTypeInternal(),
diff --git a/lib/Parse/ParseDeclCXX.cpp b/lib/Parse/ParseDeclCXX.cpp
index a8d5e28cae..895aa02c79 100644
--- a/lib/Parse/ParseDeclCXX.cpp
+++ b/lib/Parse/ParseDeclCXX.cpp
@@ -3481,20 +3481,20 @@ MemInitResult Parser::ParseMemInitializer(Decl *ConstructorDecl) {
     // Parse the optional expression-list.
     ExprVector ArgExprs;
     CommaLocsTy CommaLocs;
+    auto RunSignatureHelp = [&] {
+      QualType PreferredType = Actions.ProduceCtorInitMemberSignatureHelp(
+          getCurScope(), ConstructorDecl, SS, TemplateTypeTy, ArgExprs, II,
+          T.getOpenLocation());
+      CalledSignatureHelp = true;
+      return PreferredType;
+    };
     if (Tok.isNot(tok::r_paren) &&
         ParseExpressionList(ArgExprs, CommaLocs, [&] {
-          QualType PreferredType = Actions.ProduceCtorInitMemberSignatureHelp(
-              getCurScope(), ConstructorDecl, SS, TemplateTypeTy, ArgExprs, II,
-              T.getOpenLocation());
-          CalledSignatureHelp = true;
-          Actions.CodeCompleteExpression(getCurScope(), PreferredType);
+          PreferredType.enterFunctionArgument(Tok.getLocation(),
+                                              RunSignatureHelp);
         })) {
-      if (PP.isCodeCompletionReached() && !CalledSignatureHelp) {
-        Actions.ProduceCtorInitMemberSignatureHelp(
-            getCurScope(), ConstructorDecl, SS, TemplateTypeTy, ArgExprs, II,
-            T.getOpenLocation());
-        CalledSignatureHelp = true;
-      }
+      if (PP.isCodeCompletionReached() && !CalledSignatureHelp)
+        RunSignatureHelp();
       SkipUntil(tok::r_paren, StopAtSemi);
       return true;
     }
diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index 1146afd134..575d32d8e7 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -1658,34 +1658,25 @@ Parser::ParsePostfixExpressionSuffix(ExprResult LHS) {
 
       ExprVector ArgExprs;
       CommaLocsTy CommaLocs;
-
-      if (Tok.is(tok::code_completion)) {
+      auto RunSignatureHelp = [&]() -> QualType {
         QualType PreferredType = Actions.ProduceCallSignatureHelp(
-            getCurScope(), LHS.get(), None, PT.getOpenLocation());
+            getCurScope(), LHS.get(), ArgExprs, PT.getOpenLocation());
         CalledSignatureHelp = true;
-        Actions.CodeCompleteExpression(getCurScope(), PreferredType);
-        cutOffParsing();
-        return ExprError();
-      }
-
+        return PreferredType;
+      };
       if (OpKind == tok::l_paren || !LHS.isInvalid()) {
         if (Tok.isNot(tok::r_paren)) {
           if (ParseExpressionList(ArgExprs, CommaLocs, [&] {
-                QualType PreferredType = Actions.ProduceCallSignatureHelp(
-                    getCurScope(), LHS.get(), ArgExprs, PT.getOpenLocation());
-                CalledSignatureHelp = true;
-                Actions.CodeCompleteExpression(getCurScope(), PreferredType);
+                PreferredType.enterFunctionArgument(Tok.getLocation(),
+                                                    RunSignatureHelp);
               })) {
             (void)Actions.CorrectDelayedTyposInExpr(LHS);
             // If we got an error when parsing expression list, we don't call
             // the CodeCompleteCall handler inside the parser. So call it here
             // to make sure we get overload suggestions even when we are in the
             // middle of a parameter.
-            if (PP.isCodeCompletionReached() && !CalledSignatureHelp) {
-              Actions.ProduceCallSignatureHelp(getCurScope(), LHS.get(),
-                                               ArgExprs, PT.getOpenLocation());
-              CalledSignatureHelp = true;
-            }
+            if (PP.isCodeCompletionReached() && !CalledSignatureHelp)
+              RunSignatureHelp();
             LHS = ExprError();
           } else if (LHS.isInvalid()) {
             for (auto &E : ArgExprs)
@@ -2856,18 +2847,11 @@ ExprResult Parser::ParseFoldExpression(ExprResult LHS,
 /// \endverbatim
 bool Parser::ParseExpressionList(SmallVectorImpl<Expr *> &Exprs,
                                  SmallVectorImpl<SourceLocation> &CommaLocs,
-                                 llvm::function_ref<void()> Completer) {
+                                 llvm::function_ref<void()> ExpressionStarts) {
   bool SawError = false;
   while (1) {
-    if (Tok.is(tok::code_completion)) {
-      if (Completer)
-        Completer();
-      else
-        Actions.CodeCompleteExpression(getCurScope(),
-                                       PreferredType.get(Tok.getLocation()));
-      cutOffParsing();
-      return true;
-    }
+    if (ExpressionStarts)
+      ExpressionStarts();
 
     ExprResult Expr;
     if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) {
diff --git a/lib/Parse/ParseExprCXX.cpp b/lib/Parse/ParseExprCXX.cpp
index c74d103341..94055d4045 100644
--- a/lib/Parse/ParseExprCXX.cpp
+++ b/lib/Parse/ParseExprCXX.cpp
@@ -1677,20 +1677,21 @@ Parser::ParseCXXTypeConstructExpression(const DeclSpec &DS) {
     ExprVector Exprs;
     CommaLocsTy CommaLocs;
 
+    auto RunSignatureHelp = [&]() {
+      QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
+          getCurScope(), TypeRep.get()->getCanonicalTypeInternal(),
+          DS.getEndLoc(), Exprs, T.getOpenLocation());
+      CalledSignatureHelp = true;
+      return PreferredType;
+    };
+
     if (Tok.isNot(tok::r_paren)) {
       if (ParseExpressionList(Exprs, CommaLocs, [&] {
-            QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
-                getCurScope(), TypeRep.get()->getCanonicalTypeInternal(),
-                DS.getEndLoc(), Exprs, T.getOpenLocation());
-            CalledSignatureHelp = true;
-            Actions.CodeCompleteExpression(getCurScope(), PreferredType);
+            PreferredType.enterFunctionArgument(Tok.getLocation(),
+                                                RunSignatureHelp);
           })) {
-        if (PP.isCodeCompletionReached() && !CalledSignatureHelp) {
-          Actions.ProduceConstructorSignatureHelp(
-              getCurScope(), TypeRep.get()->getCanonicalTypeInternal(),
-              DS.getEndLoc(), Exprs, T.getOpenLocation());
-          CalledSignatureHelp = true;
-        }
+        if (PP.isCodeCompletionReached() && !CalledSignatureHelp)
+          RunSignatureHelp();
         SkipUntil(tok::r_paren, StopAtSemi);
         return ExprError();
       }
@@ -2846,23 +2847,21 @@ Parser::ParseCXXNewExpression(bool UseGlobal, SourceLocation Start) {
     ConstructorLParen = T.getOpenLocation();
     if (Tok.isNot(tok::r_paren)) {
       CommaLocsTy CommaLocs;
+      auto RunSignatureHelp = [&]() {
+        ParsedType TypeRep =
+            Actions.ActOnTypeName(getCurScope(), DeclaratorInfo).get();
+        QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
+            getCurScope(), TypeRep.get()->getCanonicalTypeInternal(),
+            DeclaratorInfo.getEndLoc(), ConstructorArgs, ConstructorLParen);
+        CalledSignatureHelp = true;
+        return PreferredType;
+      };
       if (ParseExpressionList(ConstructorArgs, CommaLocs, [&] {
-            ParsedType TypeRep =
-                Actions.ActOnTypeName(getCurScope(), DeclaratorInfo).get();
-            QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
-                getCurScope(), TypeRep.get()->getCanonicalTypeInternal(),
-                DeclaratorInfo.getEndLoc(), ConstructorArgs, ConstructorLParen);
-            CalledSignatureHelp = true;
-            Actions.CodeCompleteExpression(getCurScope(), PreferredType);
+            PreferredType.enterFunctionArgument(Tok.getLocation(),
+                                                RunSignatureHelp);
           })) {
-        if (PP.isCodeCompletionReached() && !CalledSignatureHelp) {
-          ParsedType TypeRep =
-              Actions.ActOnTypeName(getCurScope(), DeclaratorInfo).get();
-          Actions.ProduceConstructorSignatureHelp(
-              getCurScope(), TypeRep.get()->getCanonicalTypeInternal(),
-              DeclaratorInfo.getEndLoc(), ConstructorArgs, ConstructorLParen);
-          CalledSignatureHelp = true;
-        }
+        if (PP.isCodeCompletionReached() && !CalledSignatureHelp)
+          RunSignatureHelp();
         SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch);
         return ExprError();
       }
diff --git a/lib/Parse/ParseOpenMP.cpp b/lib/Parse/ParseOpenMP.cpp
index 782ad12aac..274073041c 100644
--- a/lib/Parse/ParseOpenMP.cpp
+++ b/lib/Parse/ParseOpenMP.cpp
@@ -424,21 +424,19 @@ void Parser::ParseOpenMPReductionInitializerForDecl(VarDecl *OmpPrivParm) {
     CommaLocsTy CommaLocs;
 
     SourceLocation LParLoc = T.getOpenLocation();
-    if (ParseExpressionList(
-            Exprs, CommaLocs, [this, OmpPrivParm, LParLoc, &Exprs] {
-              QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
-                  getCurScope(),
-                  OmpPrivParm->getType()->getCanonicalTypeInternal(),
-                  OmpPrivParm->getLocation(), Exprs, LParLoc);
-              CalledSignatureHelp = true;
-              Actions.CodeCompleteExpression(getCurScope(), PreferredType);
-            })) {
-      if (PP.isCodeCompletionReached() && !CalledSignatureHelp) {
-        Actions.ProduceConstructorSignatureHelp(
-            getCurScope(), OmpPrivParm->getType()->getCanonicalTypeInternal(),
-            OmpPrivParm->getLocation(), Exprs, LParLoc);
-        CalledSignatureHelp = true;
-      }
+    auto RunSignatureHelp = [this, OmpPrivParm, LParLoc, &Exprs]() {
+      QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
+          getCurScope(), OmpPrivParm->getType()->getCanonicalTypeInternal(),
+          OmpPrivParm->getLocation(), Exprs, LParLoc);
+      CalledSignatureHelp = true;
+      return PreferredType;
+    };
+    if (ParseExpressionList(Exprs, CommaLocs, [&] {
+          PreferredType.enterFunctionArgument(Tok.getLocation(),
+                                              RunSignatureHelp);
+        })) {
+      if (PP.isCodeCompletionReached() && !CalledSignatureHelp)
+        RunSignatureHelp();
       Actions.ActOnInitializerError(OmpPrivParm);
       SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
     } else {
@@ -893,7 +891,7 @@ Parser::DeclGroupPtrTy Parser::ParseOpenMPDeclarativeDirectiveWithExtDecl(
     SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>, OMPC_unknown + 1>
     FirstClauses(OMPC_unknown + 1);
     if (Tok.is(tok::annot_pragma_openmp_end)) {
-      Diag(Tok, diag::err_omp_expected_clause) 
+      Diag(Tok, diag::err_omp_expected_clause)
           << getOpenMPDirectiveName(OMPD_requires);
       break;
     }
@@ -2039,7 +2037,7 @@ static OpenMPMapClauseKind isMapType(Parser &P) {
 
 /// Parse map-type in map clause.
 /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
-/// where, map-type ::= to | from | tofrom | alloc | release | delete 
+/// where, map-type ::= to | from | tofrom | alloc | release | delete
 static void parseMapType(Parser &P, Parser::OpenMPVarListDataTy &Data) {
   Token Tok = P.getCurToken();
   if (Tok.is(tok::colon)) {