From 1a480c403a3b141ab89c9c59cf7b681102a1bfab Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Fri, 27 Aug 2010 17:35:51 +0000
Subject: [PATCH] Suggest "const" and "volatile" code completions after a
 function declarator, the very definition of "low-hanging fruit".

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@112274 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Sema/CodeCompleteConsumer.h |  4 +++-
 include/clang/Sema/Sema.h                 |  1 +
 lib/Frontend/ASTUnit.cpp                  |  1 +
 lib/Parse/ParseDecl.cpp                   |  5 +++++
 lib/Sema/SemaCodeComplete.cpp             | 16 ++++++++++++++++
 test/Index/complete-memfunc-cvquals.cpp   |  8 ++++++++
 6 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/include/clang/Sema/CodeCompleteConsumer.h b/include/clang/Sema/CodeCompleteConsumer.h
index 28210576e0..edc6331af0 100644
--- a/include/clang/Sema/CodeCompleteConsumer.h
+++ b/include/clang/Sema/CodeCompleteConsumer.h
@@ -201,7 +201,9 @@ public:
     /// unless they come from an appropriate natural-language dictionary.
     CCC_NaturalLanguage,
     /// \brief Code completion for a selector, as in an @selector expression.
-    CCC_SelectorName
+    CCC_SelectorName,
+    /// \brief Code completion within a type-qualifier list.
+    CCC_TypeQualifiers
   };
 
 private:
diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index 43f99ae284..974381668b 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -4332,6 +4332,7 @@ public:
                                                SourceLocation OpLoc,
                                                bool IsArrow);
   virtual void CodeCompleteTag(Scope *S, unsigned TagSpec);
+  virtual void CodeCompleteTypeQualifiers(DeclSpec &DS);
   virtual void CodeCompleteCase(Scope *S);
   virtual void CodeCompleteCall(Scope *S, Expr *Fn,
                                 Expr **Args, unsigned NumArgs);
diff --git a/lib/Frontend/ASTUnit.cpp b/lib/Frontend/ASTUnit.cpp
index 851c6669fe..c76488b2c6 100644
--- a/lib/Frontend/ASTUnit.cpp
+++ b/lib/Frontend/ASTUnit.cpp
@@ -1555,6 +1555,7 @@ void CalculateHiddenNames(const CodeCompletionContext &Context,
   case CodeCompletionContext::CCC_PreprocessorDirective:
   case CodeCompletionContext::CCC_NaturalLanguage:
   case CodeCompletionContext::CCC_SelectorName:
+  case CodeCompletionContext::CCC_TypeQualifiers:
     // We're looking for nothing, or we're looking for names that cannot
     // be hidden.
     return;
diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 0cc9103c05..c73b6085ea 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -2442,6 +2442,11 @@ void Parser::ParseTypeQualifierListOpt(DeclSpec &DS, bool GNUAttributesAllowed,
     SourceLocation Loc = Tok.getLocation();
 
     switch (Tok.getKind()) {
+    case tok::code_completion:
+      Actions.CodeCompleteTypeQualifiers(DS);
+      ConsumeCodeCompletionToken();
+      break;
+        
     case tok::kw_const:
       isInvalid = DS.SetTypeQual(DeclSpec::TQ_const   , Loc, PrevSpec, DiagID,
                                  getLang());
diff --git a/lib/Sema/SemaCodeComplete.cpp b/lib/Sema/SemaCodeComplete.cpp
index 384cf524c9..57ec3297dc 100644
--- a/lib/Sema/SemaCodeComplete.cpp
+++ b/lib/Sema/SemaCodeComplete.cpp
@@ -2761,6 +2761,22 @@ void Sema::CodeCompleteTag(Scope *S, unsigned TagSpec) {
                             Results.data(),Results.size());
 }
 
+void Sema::CodeCompleteTypeQualifiers(DeclSpec &DS) {
+  ResultBuilder Results(*this);
+  Results.EnterNewScope();
+  if (!(DS.getTypeQualifiers() & DeclSpec::TQ_const))
+    Results.AddResult("const");
+  if (!(DS.getTypeQualifiers() & DeclSpec::TQ_volatile))
+    Results.AddResult("volatile");
+  if (getLangOptions().C99 &&
+      !(DS.getTypeQualifiers() & DeclSpec::TQ_restrict))
+    Results.AddResult("restrict");
+  Results.ExitScope();
+  HandleCodeCompleteResults(this, CodeCompleter, 
+                            CodeCompletionContext::CCC_TypeQualifiers,
+                            Results.data(), Results.size());
+}
+
 void Sema::CodeCompleteCase(Scope *S) {
   if (getCurFunction()->SwitchStack.empty() || !CodeCompleter)
     return;
diff --git a/test/Index/complete-memfunc-cvquals.cpp b/test/Index/complete-memfunc-cvquals.cpp
index 08acdd18c1..6635bed6ff 100644
--- a/test/Index/complete-memfunc-cvquals.cpp
+++ b/test/Index/complete-memfunc-cvquals.cpp
@@ -76,3 +76,11 @@ void Foo::bingo() volatile {
 // CHECK-IMPLICIT-VOLATILE: FunctionDecl:{ResultType void}{TypedText babble}{LeftParen (}{RightParen )}{Informative  const volatile} (15)
 // CHECK-IMPLICIT-VOLATILE-NOT: baz
 // CHECK-IMPLICIT-VOLATILE: FunctionDecl:{ResultType void}{TypedText bingo}{LeftParen (}{RightParen )}{Informative  volatile} (14)
+
+// RUN: c-index-test -code-completion-at=%s:4:17 %s | FileCheck -check-prefix=CHECK-CVQUAL-AFTER %s
+// CHECK-CVQUAL-AFTER: NotImplemented:{TypedText const} (30)
+// CHECK-CVQUAL-AFTER: NotImplemented:{TypedText volatile} (30)
+
+// RUN: c-index-test -code-completion-at=%s:4:23 %s | FileCheck -check-prefix=CHECK-CVQUAL-AFTER2 %s
+// CHECK-CVQUAL-AFTER2-NOT: NotImplemented:{TypedText const} (30)
+// CHECK-CVQUAL-AFTER2: NotImplemented:{TypedText volatile} (30)
-- 
2.40.0