Introduce four new code-completion hooks for C++:

  - after "using", show anything that can be a nested-name-specifier.
  - after "using namespace", show any visible namespaces or namespace aliases
  - after "namespace", show any namespace definitions in the current scope
  - after "namespace identifier = ", show any visible namespaces or
    namespace aliases



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@82251 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 122 insertions, 2 deletions

diff --git a/lib/Parse/ParseDeclCXX.cpp b/lib/Parse/ParseDeclCXX.cpp
index 1b82c06bf8..59a6e6281c 100644
--- a/lib/Parse/ParseDeclCXX.cpp
+++ b/lib/Parse/ParseDeclCXX.cpp
@@ -47,6 +47,11 @@ Parser::DeclPtrTy Parser::ParseNamespace(unsigned Context,
   assert(Tok.is(tok::kw_namespace) && "Not a namespace!");
   SourceLocation NamespaceLoc = ConsumeToken();  // eat the 'namespace'.
 
+  if (Tok.is(tok::code_completion)) {
+    Actions.CodeCompleteNamespaceDecl(CurScope);
+    ConsumeToken();
+  }
+  
   SourceLocation IdentLoc;
   IdentifierInfo *Ident = 0;
 
@@ -115,6 +120,11 @@ Parser::DeclPtrTy Parser::ParseNamespaceAlias(SourceLocation NamespaceLoc,
 
   ConsumeToken(); // eat the '='.
 
+  if (Tok.is(tok::code_completion)) {
+    Actions.CodeCompleteNamespaceAliasDecl(CurScope);
+    ConsumeToken();
+  }
+  
   CXXScopeSpec SS;
   // Parse (optional) nested-name-specifier.
   ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/0, false);
@@ -188,6 +198,11 @@ Parser::DeclPtrTy Parser::ParseUsingDirectiveOrDeclaration(unsigned Context,
   // Eat 'using'.
   SourceLocation UsingLoc = ConsumeToken();
 
+  if (Tok.is(tok::code_completion)) {
+    Actions.CodeCompleteUsing(CurScope);
+    ConsumeToken();
+  }
+  
   if (Tok.is(tok::kw_namespace))
     // Next token after 'using' is 'namespace' so it must be using-directive
     return ParseUsingDirective(Context, UsingLoc, DeclEnd);
@@ -214,6 +229,11 @@ Parser::DeclPtrTy Parser::ParseUsingDirective(unsigned Context,
   // Eat 'namespace'.
   SourceLocation NamespcLoc = ConsumeToken();
 
+  if (Tok.is(tok::code_completion)) {
+    Actions.CodeCompleteUsingDirective(CurScope);
+    ConsumeToken();
+  }
+  
   CXXScopeSpec SS;
   // Parse (optional) nested-name-specifier.
   ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/0, false);
diff --git a/lib/Sema/CodeCompleteConsumer.cpp b/lib/Sema/CodeCompleteConsumer.cpp
index 2deaedcf09..fd187c5ef9 100644
--- a/lib/Sema/CodeCompleteConsumer.cpp
+++ b/lib/Sema/CodeCompleteConsumer.cpp
@@ -118,6 +118,63 @@ CodeCompleteConsumer::CodeCompleteQualifiedId(Scope *S,
   ProcessCodeCompleteResults(Results.data(), Results.size());
 }
 
+void CodeCompleteConsumer::CodeCompleteUsing(Scope *S) { 
+  ResultSet Results(*this, &CodeCompleteConsumer::IsNestedNameSpecifier);
+  
+  // If we aren't in class scope, we could see the "namespace" keyword.
+  if (!S->isClassScope())
+    Results.MaybeAddResult(Result("namespace", 0));
+    
+  // After "using", we can see anything that would start a 
+  // nested-name-specifier.
+  CollectLookupResults(S, 0, Results);
+  
+  ProcessCodeCompleteResults(Results.data(), Results.size());
+}
+
+void CodeCompleteConsumer::CodeCompleteUsingDirective(Scope *S) { 
+  // After "using namespace", we expect to see a namespace name or namespace
+  // alias.
+  ResultSet Results(*this, &CodeCompleteConsumer::IsNamespaceOrAlias);
+  CollectLookupResults(S, 0, Results);
+  ProcessCodeCompleteResults(Results.data(), Results.size());  
+}
+
+void CodeCompleteConsumer::CodeCompleteNamespaceDecl(Scope *S) { 
+  ResultSet Results(*this, &CodeCompleteConsumer::IsNamespace);
+  DeclContext *Ctx = (DeclContext *)S->getEntity();
+  if (!S->getParent())
+    Ctx = getSema().Context.getTranslationUnitDecl();
+
+  if (Ctx && Ctx->isFileContext()) {
+    // We only want to see those namespaces that have already been defined
+    // within this scope, because its likely that the user is creating an
+    // extended namespace declaration. Keep track of the most recent 
+    // definition of each namespace.
+    std::map<NamespaceDecl *, NamespaceDecl *> OrigToLatest;
+    for (DeclContext::specific_decl_iterator<NamespaceDecl> 
+           NS(Ctx->decls_begin()), NSEnd(Ctx->decls_end());
+         NS != NSEnd; ++NS)
+      OrigToLatest[NS->getOriginalNamespace()] = *NS;
+
+    // Add the most recent definition (or extended definition) of each 
+    // namespace to the list of results.
+    for (std::map<NamespaceDecl *, NamespaceDecl *>::iterator 
+          NS = OrigToLatest.begin(), NSEnd = OrigToLatest.end();
+         NS != NSEnd; ++NS)
+      Results.MaybeAddResult(Result(NS->second, 0));
+  }
+  
+  ProcessCodeCompleteResults(Results.data(), Results.size());  
+}
+
+void CodeCompleteConsumer::CodeCompleteNamespaceAliasDecl(Scope *S) { 
+  // After "namespace", we expect to see a namespace  or alias.
+  ResultSet Results(*this, &CodeCompleteConsumer::IsNamespaceOrAlias);
+  CollectLookupResults(S, 0, Results);
+  ProcessCodeCompleteResults(Results.data(), Results.size());  
+}
+
 void CodeCompleteConsumer::ResultSet::MaybeAddResult(Result R) {
   if (R.Kind != Result::RK_Declaration) {
     // For non-declaration results, just add the result.
@@ -454,6 +511,17 @@ bool CodeCompleteConsumer::IsUnion(NamedDecl *ND) const {
   return false;
 }
 
+/// \brief Determines whether the given declaration is a namespace.
+bool CodeCompleteConsumer::IsNamespace(NamedDecl *ND) const {
+  return isa<NamespaceDecl>(ND);
+}
+
+/// \brief Determines whether the given declaration is a namespace or 
+/// namespace alias.
+bool CodeCompleteConsumer::IsNamespaceOrAlias(NamedDecl *ND) const {
+  return isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND);
+}
+
 namespace {
   struct VISIBILITY_HIDDEN SortCodeCompleteResult {
     typedef CodeCompleteConsumer::Result Result;
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 2952c843f4..8bec9d54f5 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -3635,11 +3635,13 @@ public:
   virtual void CodeCompleteMemberReferenceExpr(Scope *S, ExprTy *Base,
                                                SourceLocation OpLoc,
                                                bool IsArrow);
-  
   virtual void CodeCompleteTag(Scope *S, unsigned TagSpec);
-
   virtual void CodeCompleteQualifiedId(Scope *S, const CXXScopeSpec &SS,
                                        bool EnteringContext);
+  virtual void CodeCompleteUsing(Scope *S);
+  virtual void CodeCompleteUsingDirective(Scope *S);
+  virtual void CodeCompleteNamespaceDecl(Scope *S);
+  virtual void CodeCompleteNamespaceAliasDecl(Scope *S);
   //@}
   
   //===--------------------------------------------------------------------===//
diff --git a/lib/Sema/SemaCodeComplete.cpp b/lib/Sema/SemaCodeComplete.cpp
index bfee4d8b76..50b8ffd1f4 100644
--- a/lib/Sema/SemaCodeComplete.cpp
+++ b/lib/Sema/SemaCodeComplete.cpp
@@ -72,3 +72,33 @@ void Sema::CodeCompleteQualifiedId(Scope *S, const CXXScopeSpec &SS,
                                       (NestedNameSpecifier *)SS.getScopeRep(),
                                          EnteringContext);
 }
+
+void Sema::CodeCompleteUsing(Scope *S) {
+  if (!CodeCompleter)
+    return;
+  
+  CodeCompleter->CodeCompleteUsing(S);
+}
+
+void Sema::CodeCompleteUsingDirective(Scope *S) {
+  if (!CodeCompleter)
+    return;
+  
+  CodeCompleter->CodeCompleteUsingDirective(S);
+}
+
+void Sema::CodeCompleteNamespaceDecl(Scope *S)  {
+  if (!CodeCompleter)
+    return;
+  
+  CodeCompleter->CodeCompleteNamespaceDecl(S);
+}
+
+void Sema::CodeCompleteNamespaceAliasDecl(Scope *S)  {
+  if (!CodeCompleter)
+    return;
+  
+  CodeCompleter->CodeCompleteNamespaceAliasDecl(S);
+}
+
+