[clang] Introduce new completion context types

Summary: New name suggestions were being used in places where existing names should have been used, this patch tries to fix some of those situations.

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: arphaman, cfe-commits

Differential Revision: https://reviews.llvm.org/D53191

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@345152 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 42 insertions, 26 deletions

diff --git a/include/clang/Sema/CodeCompleteConsumer.h b/include/clang/Sema/CodeCompleteConsumer.h
index 2c5662a840..5e46a84128 100644
--- a/include/clang/Sema/CodeCompleteConsumer.h
+++ b/include/clang/Sema/CodeCompleteConsumer.h
@@ -272,11 +272,15 @@ public:
     CCC_Type,
 
     /// Code completion occurred where a new name is expected.
-    CCC_Name,
+    CCC_NewName,
 
-    /// Code completion occurred where a new name is expected and a
-    /// qualified name is permissible.
-    CCC_PotentiallyQualifiedName,
+    /// Code completion occurred where both a new name and an existing symbol is
+    /// permissible.
+    CCC_SymbolOrNewName,
+
+    /// Code completion occurred where an existing name(such as type, function
+    /// or variable) is expected.
+    CCC_Symbol,
 
     /// Code completion occurred where an macro is being defined.
     CCC_MacroName,
diff --git a/lib/Frontend/ASTUnit.cpp b/lib/Frontend/ASTUnit.cpp
index c999458ee6..8b87a20dc1 100644
--- a/lib/Frontend/ASTUnit.cpp
+++ b/lib/Frontend/ASTUnit.cpp
@@ -282,7 +282,7 @@ void ASTUnit::enableSourceFileDiagnostics() {
 
 /// Determine the set of code-completion contexts in which this
 /// declaration should be shown.
-static unsigned getDeclShowContexts(const NamedDecl *ND,
+static uint64_t getDeclShowContexts(const NamedDecl *ND,
                                     const LangOptions &LangOpts,
                                     bool &IsNestedNameSpecifier) {
   IsNestedNameSpecifier = false;
@@ -436,14 +436,15 @@ void ASTUnit::CacheCodeCompletionResults() {
           | (1LL << CodeCompletionContext::CCC_UnionTag)
           | (1LL << CodeCompletionContext::CCC_ClassOrStructTag)
           | (1LL << CodeCompletionContext::CCC_Type)
-          | (1LL << CodeCompletionContext::CCC_PotentiallyQualifiedName)
+          | (1LL << CodeCompletionContext::CCC_Symbol)
+          | (1LL << CodeCompletionContext::CCC_SymbolOrNewName)
           | (1LL << CodeCompletionContext::CCC_ParenthesizedExpression);
 
         if (isa<NamespaceDecl>(R.Declaration) ||
             isa<NamespaceAliasDecl>(R.Declaration))
           NNSContexts |= (1LL << CodeCompletionContext::CCC_Namespace);
 
-        if (unsigned RemainingContexts
+        if (uint64_t RemainingContexts
                                 = NNSContexts & ~CachedResult.ShowInContexts) {
           // If there any contexts where this completion can be a
           // nested-name-specifier but isn't already an option, create a
@@ -1951,8 +1952,8 @@ static void CalculateHiddenNames(const CodeCompletionContext &Context,
   case CodeCompletionContext::CCC_ObjCPropertyAccess:
   case CodeCompletionContext::CCC_Namespace:
   case CodeCompletionContext::CCC_Type:
-  case CodeCompletionContext::CCC_Name:
-  case CodeCompletionContext::CCC_PotentiallyQualifiedName:
+  case CodeCompletionContext::CCC_Symbol:
+  case CodeCompletionContext::CCC_SymbolOrNewName:
   case CodeCompletionContext::CCC_ParenthesizedExpression:
   case CodeCompletionContext::CCC_ObjCInterfaceName:
     break;
@@ -1977,6 +1978,7 @@ static void CalculateHiddenNames(const CodeCompletionContext &Context,
   case CodeCompletionContext::CCC_ObjCClassMessage:
   case CodeCompletionContext::CCC_ObjCCategoryName:
   case CodeCompletionContext::CCC_IncludedFile:
+  case CodeCompletionContext::CCC_NewName:
     // We're looking for nothing, or we're looking for names that cannot
     // be hidden.
     return;
diff --git a/lib/Sema/CodeCompleteConsumer.cpp b/lib/Sema/CodeCompleteConsumer.cpp
index 2058f36b77..33b9282843 100644
--- a/lib/Sema/CodeCompleteConsumer.cpp
+++ b/lib/Sema/CodeCompleteConsumer.cpp
@@ -49,6 +49,8 @@ bool CodeCompletionContext::wantConstructorResults() const {
   case CCC_Expression:
   case CCC_ObjCMessageReceiver:
   case CCC_ParenthesizedExpression:
+  case CCC_Symbol:
+  case CCC_SymbolOrNewName:
     return true;
 
   case CCC_TopLevel:
@@ -65,8 +67,7 @@ bool CodeCompletionContext::wantConstructorResults() const {
   case CCC_ObjCProtocolName:
   case CCC_Namespace:
   case CCC_Type:
-  case CCC_Name:
-  case CCC_PotentiallyQualifiedName:
+  case CCC_NewName:
   case CCC_MacroName:
   case CCC_MacroNameUse:
   case CCC_PreprocessorExpression:
@@ -128,10 +129,12 @@ StringRef clang::getCompletionKindString(CodeCompletionContext::Kind Kind) {
     return "Namespace";
   case CCKind::CCC_Type:
     return "Type";
-  case CCKind::CCC_Name:
-    return "Name";
-  case CCKind::CCC_PotentiallyQualifiedName:
-    return "PotentiallyQualifiedName";
+  case CCKind::CCC_NewName:
+    return "NewName";
+  case CCKind::CCC_Symbol:
+    return "Symbol";
+  case CCKind::CCC_SymbolOrNewName:
+    return "SymbolOrNewName";
   case CCKind::CCC_MacroName:
     return "MacroName";
   case CCKind::CCC_MacroNameUse:
diff --git a/lib/Sema/SemaCodeComplete.cpp b/lib/Sema/SemaCodeComplete.cpp
index c482207fe5..3c355552cf 100644
--- a/lib/Sema/SemaCodeComplete.cpp
+++ b/lib/Sema/SemaCodeComplete.cpp
@@ -3753,11 +3753,14 @@ void Sema::CodeCompleteDeclSpec(Scope *S, DeclSpec &DS,
                                 bool AllowNonIdentifiers,
                                 bool AllowNestedNameSpecifiers) {
   typedef CodeCompletionResult Result;
-  ResultBuilder Results(*this, CodeCompleter->getAllocator(),
-                        CodeCompleter->getCodeCompletionTUInfo(),
-                        AllowNestedNameSpecifiers
-                          ? CodeCompletionContext::CCC_PotentiallyQualifiedName
-                          : CodeCompletionContext::CCC_Name);
+  ResultBuilder Results(
+      *this, CodeCompleter->getAllocator(),
+      CodeCompleter->getCodeCompletionTUInfo(),
+      AllowNestedNameSpecifiers
+          // FIXME: Try to separate codepath leading here to deduce whether we
+          // need an existing symbol or a new one.
+          ? CodeCompletionContext::CCC_SymbolOrNewName
+          : CodeCompletionContext::CCC_NewName);
   Results.EnterNewScope();
 
   // Type qualifiers can come after names.
@@ -4841,7 +4844,7 @@ void Sema::CodeCompleteQualifiedId(Scope *S, CXXScopeSpec &SS,
   // it can be useful for global code completion which have information about
   // contexts/symbols that are not in the AST.
   if (SS.isInvalid()) {
-    CodeCompletionContext CC(CodeCompletionContext::CCC_Name);
+    CodeCompletionContext CC(CodeCompletionContext::CCC_Symbol);
     CC.setCXXScopeSpecifier(SS);
     HandleCodeCompleteResults(this, CodeCompleter, CC, nullptr, 0);
     return;
@@ -4859,7 +4862,7 @@ void Sema::CodeCompleteQualifiedId(Scope *S, CXXScopeSpec &SS,
 
   ResultBuilder Results(*this, CodeCompleter->getAllocator(),
                         CodeCompleter->getCodeCompletionTUInfo(),
-                        CodeCompletionContext::CCC_Name);
+                        CodeCompletionContext::CCC_Symbol);
   Results.EnterNewScope();
 
   // The "template" keyword can follow "::" in the grammar, but only
@@ -4899,7 +4902,10 @@ void Sema::CodeCompleteUsing(Scope *S) {
 
   ResultBuilder Results(*this, CodeCompleter->getAllocator(),
                         CodeCompleter->getCodeCompletionTUInfo(),
-                        CodeCompletionContext::CCC_PotentiallyQualifiedName,
+                        // This can be both a using alias or using
+                        // declaration, in the former we expect a new name and a
+                        // symbol in the latter case.
+                        CodeCompletionContext::CCC_SymbolOrNewName,
                         &ResultBuilder::IsNestedNameSpecifier);
   Results.EnterNewScope();
 
@@ -5051,7 +5057,7 @@ void Sema::CodeCompleteConstructorInitializer(
 
   ResultBuilder Results(*this, CodeCompleter->getAllocator(),
                         CodeCompleter->getCodeCompletionTUInfo(),
-                        CodeCompletionContext::CCC_PotentiallyQualifiedName);
+                        CodeCompletionContext::CCC_Symbol);
   Results.EnterNewScope();
 
   // Fill in any already-initialized fields or base classes.
diff --git a/tools/libclang/CIndexCodeCompletion.cpp b/tools/libclang/CIndexCodeCompletion.cpp
index 4e4dcdb58c..752d7a10e0 100644
--- a/tools/libclang/CIndexCodeCompletion.cpp
+++ b/tools/libclang/CIndexCodeCompletion.cpp
@@ -487,7 +487,8 @@ static unsigned long long getContextsForContextKind(
       contexts = CXCompletionContext_Namespace;
       break;
     }
-    case CodeCompletionContext::CCC_PotentiallyQualifiedName: {
+    case CodeCompletionContext::CCC_SymbolOrNewName:
+    case CodeCompletionContext::CCC_Symbol: {
       contexts = CXCompletionContext_NestedNameSpecifier;
       break;
     }
@@ -539,7 +540,7 @@ static unsigned long long getContextsForContextKind(
     case CodeCompletionContext::CCC_Other:
     case CodeCompletionContext::CCC_ObjCInterface:
     case CodeCompletionContext::CCC_ObjCImplementation:
-    case CodeCompletionContext::CCC_Name:
+    case CodeCompletionContext::CCC_NewName:
     case CodeCompletionContext::CCC_MacroName:
     case CodeCompletionContext::CCC_PreprocessorExpression:
     case CodeCompletionContext::CCC_PreprocessorDirective: