[Sema] Add visited contexts to CodeCompleteContext

Summary:
This would allow code completion clients to know which context is visited during Sema code completion.

Also some changes:
 * add `EnteredContext` callback in VisibleDeclConsumer.
 * add a simple unittest for sema code completion (only for visited contexts at the moment).

Reviewers: ilya-biryukov

Reviewed By: ilya-biryukov

Subscribers: mgorny, bkramer, cfe-commits

Differential Revision: https://reviews.llvm.org/D42071

llvm-svn: 322661

1 files changed, 10 insertions, 1 deletions

diff --git a/clang/lib/Sema/SemaCodeComplete.cpp b/clang/lib/Sema/SemaCodeComplete.cpp
index f7adaf4dcd0..ac318a65fce 100644
--- a/clang/lib/Sema/SemaCodeComplete.cpp
+++ b/clang/lib/Sema/SemaCodeComplete.cpp
@@ -318,6 +318,11 @@ namespace {
     /// \brief Ignore this declaration, if it is seen again.
     void Ignore(const Decl *D) { AllDeclsFound.insert(D->getCanonicalDecl()); }
 
+    /// \brief Add a visited context.
+    void addVisitedContext(DeclContext *Ctx) {
+      CompletionContext.addVisitedContext(Ctx);
+    }
+
     /// \name Name lookup predicates
     ///
     /// These predicates can be passed to the name lookup functions to filter the
@@ -1280,7 +1285,7 @@ namespace {
   class CodeCompletionDeclConsumer : public VisibleDeclConsumer {
     ResultBuilder &Results;
     DeclContext *CurContext;
-    
+
   public:
     CodeCompletionDeclConsumer(ResultBuilder &Results, DeclContext *CurContext)
       : Results(Results), CurContext(CurContext) { }
@@ -1295,6 +1300,10 @@ namespace {
                                    false, Accessible);
       Results.AddResult(Result, CurContext, Hiding, InBaseClass);
     }
+
+    void EnteredContext(DeclContext* Ctx) override {
+      Results.addVisitedContext(Ctx);
+    }
   };
 }