[clang-tools-extra] 3d73548 - [clangd] SelectionTree should prefer lexical declcontext

[Kadir Cetinkaya via cfe-commits]

Author: Kadir Cetinkaya
Date: 2021-10-28T17:39:35+02:00
New Revision: 3d735480bd2a720af2126c80da58371690e6a02e

URL: https://github.com/llvm/llvm-project/commit/3d735480bd2a720af2126c80da58371690e6a02e
DIFF: https://github.com/llvm/llvm-project/commit/3d735480bd2a720af2126c80da58371690e6a02e.diff

LOG: [clangd] SelectionTree should prefer lexical declcontext

This is important especially for code that tries to traverse scopes as
written in code, which is the contract SelectionTree tries to satisfy.

Differential Revision: https://reviews.llvm.org/D112712

Added: 
    

Modified: 
    clang-tools-extra/clangd/Selection.cpp
    clang-tools-extra/clangd/Selection.h
    clang-tools-extra/clangd/unittests/SelectionTests.cpp

Removed: 
    


################################################################################
diff  --git a/clang-tools-extra/clangd/Selection.cpp b/clang-tools-extra/clangd/Selection.cpp
index a53673e074804..88ab1c5d058ee 100644
--- a/clang-tools-extra/clangd/Selection.cpp
+++ b/clang-tools-extra/clangd/Selection.cpp
@@ -897,7 +897,7 @@ const DeclContext &SelectionTree::Node::getDeclContext() const {
       if (CurrentNode != this)
         if (auto *DC = dyn_cast<DeclContext>(Current))
           return *DC;
-      return *Current->getDeclContext();
+      return *Current->getLexicalDeclContext();
     }
   }
   llvm_unreachable("A tree must always be rooted at TranslationUnitDecl.");

diff  --git a/clang-tools-extra/clangd/Selection.h b/clang-tools-extra/clangd/Selection.h
index 775006f40f6cc..f80ee83c4b94c 100644
--- a/clang-tools-extra/clangd/Selection.h
+++ b/clang-tools-extra/clangd/Selection.h
@@ -128,8 +128,8 @@ class SelectionTree {
     DynTypedNode ASTNode;
     // The extent to which this node is covered by the selection.
     Selection Selected;
-    // Walk up the AST to get the DeclContext of this Node,
-    // which is not the node itself.
+    // Walk up the AST to get the lexical DeclContext of this Node, which is not
+    // the node itself.
     const DeclContext &getDeclContext() const;
     // Printable node kind, like "CXXRecordDecl" or "AutoTypeLoc".
     std::string kind() const;

diff  --git a/clang-tools-extra/clangd/unittests/SelectionTests.cpp b/clang-tools-extra/clangd/unittests/SelectionTests.cpp
index 1c3bc20958486..6c6782a097db5 100644
--- a/clang-tools-extra/clangd/unittests/SelectionTests.cpp
+++ b/clang-tools-extra/clangd/unittests/SelectionTests.cpp
@@ -739,6 +739,21 @@ TEST(SelectionTest, CreateAll) {
   EXPECT_EQ(1u, Seen) << "one tree for nontrivial selection";
 }
 
+TEST(SelectionTest, DeclContextIsLexical) {
+  llvm::Annotations Test("namespace a { void $1^foo(); } void a::$2^foo();");
+  auto AST = TestTU::withCode(Test.code()).build();
+  {
+    auto ST = SelectionTree::createRight(AST.getASTContext(), AST.getTokens(),
+                                         Test.point("1"), Test.point("1"));
+    EXPECT_FALSE(ST.commonAncestor()->getDeclContext().isTranslationUnit());
+  }
+  {
+    auto ST = SelectionTree::createRight(AST.getASTContext(), AST.getTokens(),
+                                         Test.point("2"), Test.point("2"));
+    EXPECT_TRUE(ST.commonAncestor()->getDeclContext().isTranslationUnit());
+  }
+}
+
 } // namespace
 } // namespace clangd
 } // namespace clang