[PATCH] D41901: [clangd] Remove duplicates from code completion

[Ilya Biryukov via Phabricator via cfe-commits]

ilya-biryukov created this revision.
ilya-biryukov added a reviewer: sammccall.
Herald added a subscriber: klimek.

This patch removes hidden items from code completion.
Hidden items are the ones that are hidden by other items (e.g., by
other items in the child scopes).
This patch addresses a particular problem of a duplicate completion
item for the class in the following example:

  struct Adapter { void method(); };
  void Adapter::method() {
     Adapter^
  }

We should probably investigate if there are other duplicates in
completion and remove them, possibly adding assertions that it never
happens.


Repository:
  rCTE Clang Tools Extra

https://reviews.llvm.org/D41901

Files:
  clangd/CodeComplete.cpp
  unittests/clangd/CodeCompleteTests.cpp


Index: unittests/clangd/CodeCompleteTests.cpp
===================================================================
--- unittests/clangd/CodeCompleteTests.cpp
+++ unittests/clangd/CodeCompleteTests.cpp
@@ -583,6 +583,22 @@
   EXPECT_THAT(Results.items, Has("fooooo", CompletionItemKind::Function));
 }
 
+TEST(CompletionTest, NoDuplicates) {
+  auto Items = completions(R"cpp(
+struct Adapter {
+  void method();
+};
+
+void Adapter::method() {
+  Adapter^
+}
+  )cpp")
+                   .items;
+
+  // Make sure there are no duplicate entries of 'Adapter'.
+  EXPECT_THAT(Items, ElementsAre(Named("Adapter"), Named("~Adapter")));
+}
+
 } // namespace
 } // namespace clangd
 } // namespace clang
Index: clangd/CodeComplete.cpp
===================================================================
--- clangd/CodeComplete.cpp
+++ clangd/CodeComplete.cpp
@@ -294,6 +294,13 @@
     std::priority_queue<CompletionCandidate> Candidates;
     for (unsigned I = 0; I < NumResults; ++I) {
       auto &Result = Results[I];
+      // We drop hidden items, as they cannot be found by the lookup after
+      // inserting the corresponding completion item and only produce noise and
+      // duplicates in the completion list. However, there is one exception. If
+      // Result has a Qualifier which is non-informative, we can refer to an
+      // item by adding that qualifier, so we don't filter out this item.
+      if (Result.Hidden && (!Result.Qualifier || Result.QualifierIsInformative))
+        continue;
       if (!ClangdOpts.IncludeIneligibleResults &&
           (Result.Availability == CXAvailability_NotAvailable ||
            Result.Availability == CXAvailability_NotAccessible))


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D41901.129247.patch
Type: text/x-patch
Size: 1690 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20180110/3f2f05c3/attachment.bin>