[CodeCompletion] Code complete the missing C++11 keywords

This commit adds context sensitive code completion support for the C++11
keywords that currently don't have completion results.

The following keywords are supported by this patch:

alignas
constexpr
static_assert
noexcept (as a function/method qualifier)
thread_local

The following special identifiers are also supported:

final (as a method qualifier or class qualifier)
override

rdar://29219185

Differential Revision: https://reviews.llvm.org/D28286

llvm-svn: 295001

clang/include/clang/Parse/Parser.h

@@ -2385,10 +2385,10 @@ private:
                                 AR_DeclspecAttributesParsed
   };
 
-  void ParseTypeQualifierListOpt(DeclSpec &DS,
+  void ParseTypeQualifierListOpt(
-                                 unsigned AttrReqs = AR_AllAttributesParsed,
+      DeclSpec &DS, unsigned AttrReqs = AR_AllAttributesParsed,
-                                 bool AtomicAllowed = true,
+      bool AtomicAllowed = true, bool IdentifierRequired = false,
-                                 bool IdentifierRequired = false);
+      Optional<llvm::function_ref<void()>> CodeCompletionHandler = None);
   void ParseDirectDeclarator(Declarator &D);
   void ParseDecompositionDeclarator(Declarator &D);
   void ParseParenDeclarator(Declarator &D);

clang/include/clang/Sema/Sema.h

@@ -9820,6 +9820,8 @@ public:
   void CodeCompletePostfixExpression(Scope *S, ExprResult LHS);
   void CodeCompleteTag(Scope *S, unsigned TagSpec);
   void CodeCompleteTypeQualifiers(DeclSpec &DS);
+  void CodeCompleteFunctionQualifiers(DeclSpec &DS, Declarator &D,
+                                      const VirtSpecifiers *VS = nullptr);
   void CodeCompleteBracketDeclarator(Scope *S);
   void CodeCompleteCase(Scope *S);
   void CodeCompleteCall(Scope *S, Expr *Fn, ArrayRef<Expr *> Args);

clang/lib/Parse/ParseDecl.cpp

@@ -4802,9 +4802,10 @@ bool Parser::isConstructorDeclarator(bool IsUnqualified, bool DeductionGuide) {
 ///              [ only if AttReqs & AR_CXX11AttributesParsed ]
 /// Note: vendor can be GNU, MS, etc and can be explicitly controlled via
 /// AttrRequirements bitmask values.
-void Parser::ParseTypeQualifierListOpt(DeclSpec &DS, unsigned AttrReqs,
+void Parser::ParseTypeQualifierListOpt(
-                                       bool AtomicAllowed,
+    DeclSpec &DS, unsigned AttrReqs, bool AtomicAllowed,
-                                       bool IdentifierRequired) {
+    bool IdentifierRequired,
+    Optional<llvm::function_ref<void()>> CodeCompletionHandler) {
   if (getLangOpts().CPlusPlus11 && (AttrReqs & AR_CXX11AttributesParsed) &&
       isCXX11AttributeSpecifier()) {
     ParsedAttributesWithRange attrs(AttrFactory);
@@ -4822,7 +4823,10 @@ void Parser::ParseTypeQualifierListOpt(DeclSpec &DS, unsigned AttrReqs,
 
     switch (Tok.getKind()) {
     case tok::code_completion:
-      Actions.CodeCompleteTypeQualifiers(DS);
+      if (CodeCompletionHandler)
+        (*CodeCompletionHandler)();
+      else
+        Actions.CodeCompleteTypeQualifiers(DS);
       return cutOffParsing();
 
     case tok::kw_const:
@@ -5748,7 +5752,11 @@ void Parser::ParseFunctionDeclarator(Declarator &D,
 
       // Parse cv-qualifier-seq[opt].
       ParseTypeQualifierListOpt(DS, AR_NoAttributesParsed,
-                                /*AtomicAllowed*/ false);
+                                /*AtomicAllowed*/ false,
+                                /*IdentifierRequired=*/false,
+                                llvm::function_ref<void()>([&]() {
+                                  Actions.CodeCompleteFunctionQualifiers(DS, D);
+                                }));
       if (!DS.getSourceRange().getEnd().isInvalid()) {
         EndLoc = DS.getSourceRange().getEnd();
         ConstQualifierLoc = DS.getConstSpecLoc();

clang/lib/Parse/ParseDeclCXX.cpp

@@ -2285,7 +2285,11 @@ void Parser::MaybeParseAndDiagnoseDeclSpecAfterCXX11VirtSpecifierSeq(
 
   // GNU-style and C++11 attributes are not allowed here, but they will be
   // handled by the caller.  Diagnose everything else.
-  ParseTypeQualifierListOpt(DS, AR_NoAttributesParsed, false);
+  ParseTypeQualifierListOpt(
+      DS, AR_NoAttributesParsed, false,
+      /*IdentifierRequired=*/false, llvm::function_ref<void()>([&]() {
+        Actions.CodeCompleteFunctionQualifiers(DS, D, &VS);
+      }));
   D.ExtendWithDeclSpec(DS);
 
   if (D.isFunctionDeclarator()) {

clang/lib/Sema/SemaCodeComplete.cpp

@@ -1370,6 +1370,21 @@ static void AddStorageSpecifiers(Sema::ParserCompletionContext CCC,
   // in C++0x as a type specifier.
   Results.AddResult(Result("extern"));
   Results.AddResult(Result("static"));
+
+  if (LangOpts.CPlusPlus11) {
+    CodeCompletionAllocator &Allocator = Results.getAllocator();
+    CodeCompletionBuilder Builder(Allocator, Results.getCodeCompletionTUInfo());
+
+    // alignas
+    Builder.AddTypedTextChunk("alignas");
+    Builder.AddChunk(CodeCompletionString::CK_LeftParen);
+    Builder.AddPlaceholderChunk("expression");
+    Builder.AddChunk(CodeCompletionString::CK_RightParen);
+    Results.AddResult(Result(Builder.TakeString()));
+
+    Results.AddResult(Result("constexpr"));
+    Results.AddResult(Result("thread_local"));
+  }
 }
 
 static void AddFunctionSpecifiers(Sema::ParserCompletionContext CCC,
@@ -1527,6 +1542,21 @@ static void addThisCompletion(Sema &S, ResultBuilder &Results) {
   Results.AddResult(CodeCompletionResult(Builder.TakeString()));
 }
 
+static void AddStaticAssertResult(CodeCompletionBuilder &Builder,
+                                  ResultBuilder &Results,
+                                  const LangOptions &LangOpts) {
+  if (!LangOpts.CPlusPlus11)
+    return;
+
+  Builder.AddTypedTextChunk("static_assert");
+  Builder.AddChunk(CodeCompletionString::CK_LeftParen);
+  Builder.AddPlaceholderChunk("expression");
+  Builder.AddChunk(CodeCompletionString::CK_Comma);
+  Builder.AddPlaceholderChunk("message");
+  Builder.AddChunk(CodeCompletionString::CK_RightParen);
+  Results.AddResult(CodeCompletionResult(Builder.TakeString()));
+}
+
 /// \brief Add language constructs that show up for "ordinary" names.
 static void AddOrdinaryNameResults(Sema::ParserCompletionContext CCC,
                                    Scope *S,
@@ -1611,6 +1641,8 @@ static void AddOrdinaryNameResults(Sema::ParserCompletionContext CCC,
         Results.AddResult(Result(Builder.TakeString()));
       }
 
+      AddStaticAssertResult(Builder, Results, SemaRef.getLangOpts());
+
       if (CCC == Sema::PCC_Class) {
         AddTypedefResult(Results);
 
@@ -1824,6 +1856,8 @@ static void AddOrdinaryNameResults(Sema::ParserCompletionContext CCC,
     Builder.AddChunk(CodeCompletionString::CK_HorizontalSpace);
     Builder.AddPlaceholderChunk("identifier");
     Results.AddResult(Result(Builder.TakeString()));
+
+    AddStaticAssertResult(Builder, Results, SemaRef.getLangOpts());
   }
 
   // Fall through (for statement expressions).
@@ -3483,6 +3517,11 @@ void Sema::CodeCompleteDeclSpec(Scope *S, DeclSpec &DS,
     Results.AddResult(Result("restrict"));
 
   if (getLangOpts().CPlusPlus) {
+    if (getLangOpts().CPlusPlus11 &&
+        (DS.getTypeSpecType() == DeclSpec::TST_class ||
+         DS.getTypeSpecType() == DeclSpec::TST_struct))
+      Results.AddResult("final");
+
     if (AllowNonIdentifiers) {
       Results.AddResult(Result("operator")); 
     }
@@ -4013,30 +4052,54 @@ void Sema::CodeCompleteTag(Scope *S, unsigned TagSpec) {
                             Results.data(),Results.size());
 }
 
+static void AddTypeQualifierResults(DeclSpec &DS, ResultBuilder &Results,
+                                    const LangOptions &LangOpts) {
+  if (!(DS.getTypeQualifiers() & DeclSpec::TQ_const))
+    Results.AddResult("const");
+  if (!(DS.getTypeQualifiers() & DeclSpec::TQ_volatile))
+    Results.AddResult("volatile");
+  if (LangOpts.C99 && !(DS.getTypeQualifiers() & DeclSpec::TQ_restrict))
+    Results.AddResult("restrict");
+  if (LangOpts.C11 && !(DS.getTypeQualifiers() & DeclSpec::TQ_atomic))
+    Results.AddResult("_Atomic");
+  if (LangOpts.MSVCCompat && !(DS.getTypeQualifiers() & DeclSpec::TQ_unaligned))
+    Results.AddResult("__unaligned");
+}
+
 void Sema::CodeCompleteTypeQualifiers(DeclSpec &DS) {
   ResultBuilder Results(*this, CodeCompleter->getAllocator(),
                         CodeCompleter->getCodeCompletionTUInfo(),
                         CodeCompletionContext::CCC_TypeQualifiers);
   Results.EnterNewScope();
-  if (!(DS.getTypeQualifiers() & DeclSpec::TQ_const))
+  AddTypeQualifierResults(DS, Results, LangOpts);
-    Results.AddResult("const");
-  if (!(DS.getTypeQualifiers() & DeclSpec::TQ_volatile))
-    Results.AddResult("volatile");
-  if (getLangOpts().C99 &&
-      !(DS.getTypeQualifiers() & DeclSpec::TQ_restrict))
-    Results.AddResult("restrict");
-  if (getLangOpts().C11 &&
-      !(DS.getTypeQualifiers() & DeclSpec::TQ_atomic))
-    Results.AddResult("_Atomic");
-  if (getLangOpts().MSVCCompat &&
-      !(DS.getTypeQualifiers() & DeclSpec::TQ_unaligned))
-    Results.AddResult("__unaligned");
   Results.ExitScope();
   HandleCodeCompleteResults(this, CodeCompleter, 
                             Results.getCompletionContext(),
                             Results.data(), Results.size());
 }
 
+void Sema::CodeCompleteFunctionQualifiers(DeclSpec &DS, Declarator &D,
+                                          const VirtSpecifiers *VS) {
+  ResultBuilder Results(*this, CodeCompleter->getAllocator(),
+                        CodeCompleter->getCodeCompletionTUInfo(),
+                        CodeCompletionContext::CCC_TypeQualifiers);
+  Results.EnterNewScope();
+  AddTypeQualifierResults(DS, Results, LangOpts);
+  if (LangOpts.CPlusPlus11) {
+    Results.AddResult("noexcept");
+    if (D.getContext() == Declarator::MemberContext && !D.isCtorOrDtor() &&
+        !D.isStaticMember()) {
+      if (!VS || !VS->isFinalSpecified())
+        Results.AddResult("final");
+      if (!VS || !VS->isOverrideSpecified())
+        Results.AddResult("override");
+    }
+  }
+  Results.ExitScope();
+  HandleCodeCompleteResults(this, CodeCompleter, Results.getCompletionContext(),
+                            Results.data(), Results.size());
+}
+
 void Sema::CodeCompleteBracketDeclarator(Scope *S) {
   CodeCompleteExpression(S, QualType(getASTContext().getSizeType()));
 }

clang/test/CodeCompletion/keywords.cpp

@@ -0,0 +1,79 @@
+int function(int x) {
+  return x + 1;
+}
+
+int variable = 0;
+
+class Class {
+public:
+  Class() { }
+
+  int method(int x) {
+    return x + 1;
+  }
+
+  virtual void virtualMethod() {
+  }
+
+  static void staticMethod() {
+  }
+
+  static int staticVar;
+};
+
+class SubClass : public Class {
+  void virtualMethod() override final {
+  }
+};
+
+struct Struct {
+};
+
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:1:1 %s | FileCheck --check-prefix=CHECK-TOP-LEVEL %s
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:5:1 %s | FileCheck --check-prefix=CHECK-TOP-LEVEL %s
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:11:1 %s | FileCheck --check-prefix=CHECK-TOP-LEVEL %s
+// CHECK-TOP-LEVEL: alignas(<#expression#>)
+// CHECK-TOP-LEVEL: constexpr
+// CHECK-TOP-LEVEL: static_assert(<#expression#>, <#message#>)
+// CHECK-TOP-LEVEL: thread_local
+// CHECK-TOP-LEVEL-NOT: final
+// CHECK-TOP-LEVEL-NOT: noexcept
+
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:1:14 %s | FileCheck --check-prefix=CHECK-PARAM %s
+// CHECK-PARAM-NOT: alignas
+// CHECK-PARAM-NOT: constexpr
+// CHECK-PARAM-NOT: final
+// CHECK-PARAM-NOT: thread_local
+
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:21:10 %s | FileCheck --check-prefix=CHECK-STATICVAR1 %s
+// CHECK-STATICVAR1: constexpr
+// CHECK-STATICVAR1: thread_local
+
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:7:13 %s | FileCheck --check-prefix=CHECK-CLASS-QUALIFIER %s
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:24:16 %s | FileCheck --check-prefix=CHECK-CLASS-QUALIFIER %s
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:29:15 %s | FileCheck --check-prefix=CHECK-CLASS-QUALIFIER %s
+// CHECK-CLASS-QUALIFIER: final
+
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:1:21 %s | FileCheck --check-prefix=CHECK-FUNCTION-QUALIFIER %s
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:9:11 %s | FileCheck --check-prefix=CHECK-FUNCTION-QUALIFIER %s
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:18:30 %s | FileCheck --check-prefix=CHECK-FUNCTION-QUALIFIER %s
+// CHECK-FUNCTION-QUALIFIER: noexcept
+// CHECK-FUNCTION-QUALIFIER-NOT: final
+// CHECK-FUNCTION-QUALIFIER-NOT: override
+
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:11:21 %s | FileCheck --check-prefix=CHECK-METHOD-QUALIFIER %s
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:15:32 %s | FileCheck --check-prefix=CHECK-METHOD-QUALIFIER %s
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:25:24 %s | FileCheck --check-prefix=CHECK-METHOD-QUALIFIER %s
+// CHECK-METHOD-QUALIFIER: final
+// CHECK-METHOD-QUALIFIER: noexcept
+// CHECK-METHOD-QUALIFIER: override
+
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:25:33 %s | FileCheck --check-prefix=CHECK-OVERRIDE-SPECIFIED %s
+// CHECK-OVERRIDE-SPECIFIED: final
+// CHECK-OVERRIDE-SPECIFIED: noexcept
+// CHECK-OVERRIDE-SPECIFIED-NOT: override
+
+// RUN: %clang_cc1 -std=c++11 -code-completion-at=%s:25:39 %s | FileCheck --check-prefix=CHECK-OVERRIDE-FINAL-SPECIFIED %s
+// CHECK-OVERRIDE-FINAL-SPECIFIED: noexcept
+// CHECK-OVERRIDE-FINAL-SPECIFIED-NOT: final
+// CHECK-OVERRIDE-FINAL-SPECIFIED-NOT: override

clang/test/CodeCompletion/ordinary-name-cxx11.cpp

@@ -39,10 +39,12 @@ void foo() {
   // CHECK-CC1-NEXT: COMPLETION: Pattern : [#size_t#]sizeof(<#expression-or-type#>)
   // CHECK-CC1-NEXT: COMPLETION: Pattern : [#size_t#]sizeof...(<#parameter-pack#>)
   // CHECK-CC1-NEXT: COMPLETION: static
+  // CHECK-CC1-NEXT: COMPLETION: Pattern : static_assert(<#expression#>, <#message#>)
   // CHECK-CC1-NEXT: COMPLETION: Pattern : static_cast<<#type#>>(<#expression#>)
   // CHECK-CC1-NEXT: COMPLETION: struct
   // CHECK-CC1-NEXT: COMPLETION: Pattern : switch(<#condition#>){
   // CHECK-CC1: COMPLETION: t : t
+  // CHECK-CC1-NEXT: COMPLETION: thread_local
   // CHECK-CC1-NEXT: COMPLETION: Pattern : [#void#]throw <#expression#>
   // CHECK-CC1-NEXT: COMPLETION: Pattern : [#bool#]true
   // CHECK-CC1-NEXT: COMPLETION: Pattern : try{<#statements#>
@@ -72,6 +74,7 @@ void foo() {
   // CHECK-CC2-NEXT: COMPLETION: char32
   // CHECK-CC2-NEXT: COMPLETION: class
   // CHECK-CC2-NEXT: COMPLETION: const
+  // CHECK-CC2-NEXT: COMPLETION: constexpr
   // CHECK-CC2-NEXT: COMPLETION: Pattern : decltype(<#expression#>)
   // CHECK-CC2-NEXT: COMPLETION: double
   // CHECK-CC2-NEXT: COMPLETION: enum
@@ -86,10 +89,12 @@ void foo() {
   // CHECK-CC2-NEXT: COMPLETION: short
   // CHECK-CC2-NEXT: COMPLETION: signed
   // CHECK-CC2-NEXT: COMPLETION: static
+  // CHECK-CC2-NEXT: COMPLETION: Pattern : static_assert(<#expression#>, <#message#>)
   // CHECK-CC2-NEXT: COMPLETION: struct
   // CHECK-CC2-NEXT: COMPLETION: t : t
   // CHECK-CC2-NEXT: COMPLETION: Pattern : template <#declaration#>
   // CHECK-CC2-NEXT: COMPLETION: Pattern : template<<#parameters#>>
+  // CHECK-CC2-NEXT: COMPLETION: thread_local
   // CHECK-CC2-NEXT: COMPLETION: TYPEDEF : TYPEDEF
   // CHECK-CC2-NEXT: COMPLETION: Pattern : typedef <#type#> <#name#>
   // CHECK-CC2-NEXT: COMPLETION: Pattern : typename <#qualifier#>::<#name#>
@@ -111,6 +116,7 @@ void foo() {
   // CHECK-CC3-NEXT: COMPLETION: char32_t
   // CHECK-CC3-NEXT: COMPLETION: class
   // CHECK-CC3-NEXT: COMPLETION: const
+  // CHECK-CC3-NEXT: COMPLETION: constexpr
   // CHECK-CC3-NEXT: COMPLETION: Pattern : decltype(<#expression#>)
   // CHECK-CC3-NEXT: COMPLETION: double
   // CHECK-CC3-NEXT: COMPLETION: enum
@@ -129,8 +135,10 @@ void foo() {
   // CHECK-CC3-NEXT: COMPLETION: short
   // CHECK-CC3-NEXT: COMPLETION: signed
   // CHECK-CC3-NEXT: COMPLETION: static
+  // CHECK-CC3-NEXT: COMPLETION: Pattern : static_assert(<#expression#>, <#message#>)
   // CHECK-CC3-NEXT: COMPLETION: struct
   // CHECK-CC3-NEXT: COMPLETION: Pattern : template<<#parameters#>>
+  // CHECK-CC3-NEXT: COMPLETION: thread_local
   // CHECK-CC3-NEXT: COMPLETION: Pattern : typedef <#type#> <#name#>
   // CHECK-CC3-NEXT: COMPLETION: Pattern : typename <#qualifier#>::<#name#>
   // CHECK-CC3-NEXT: COMPLETION: Pattern : typeof <#expression#>
@@ -227,6 +235,7 @@ void foo() {
   // CHECK-NO-RTTI-NEXT: COMPLETION: Pattern : [#size_t#]sizeof(<#expression-or-type#>)
   // CHECK-NO-RTTI-NEXT: COMPLETION: Pattern : [#size_t#]sizeof...(<#parameter-pack#>)
   // CHECK-NO-RTTI-NEXT: COMPLETION: static
+  // CHECK-NO-RTTI-NEXT: COMPLETION: Pattern : static_assert(<#expression#>, <#message#>)
   // CHECK-NO-RTTI-NEXT: COMPLETION: Pattern : static_cast<<#type#>>(<#expression#>)
   // CHECK-NO-RTTI-NEXT: COMPLETION: struct
   // CHECK-NO-RTTI-NEXT: COMPLETION: Pattern : switch(<#condition#>){