[clangd] Avoid recursion on UnresolvedUsingValueDecl during semantic …

…highlighting Fixes clangd/clangd#1313 Differential Revision: https://reviews.llvm.org/D134827
llvm · Mar 19, 2023 · 7138e75 · 7138e75
1 parent 2538e55
commit 7138e75
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Showing 2 changed files with 10 additions and 2 deletions.
diff --git a/clang-tools-extra/clangd/SemanticHighlighting.cpp b/clang-tools-extra/clangd/SemanticHighlighting.cpp
@@ -156,7 +156,7 @@ std::optional<HighlightingKind> kindForDecl(const NamedDecl *D,
     return HighlightingKind::Concept;
   if (const auto *UUVD = dyn_cast<UnresolvedUsingValueDecl>(D)) {
     auto Targets = Resolver->resolveUsingValueDecl(UUVD);
-    if (!Targets.empty()) {
+    if (!Targets.empty() && Targets[0] != UUVD) {
       return kindForDecl(Targets[0], Resolver);
     }
     return HighlightingKind::Unknown;

diff --git a/clang-tools-extra/clangd/unittests/SemanticHighlightingTests.cpp b/clang-tools-extra/clangd/unittests/SemanticHighlightingTests.cpp
@@ -1045,7 +1045,15 @@ sizeof...($TemplateParameter[[Elements]]);
           auto $LocalVariable_def[[s]] = $Operator[[new]] $Class[[Foo]]$Bracket[[<]]$TemplateParameter[[T]]$Bracket[[>]]();
           $Operator[[delete]] $LocalVariable[[s]];
         }
-      )cpp"};
+      )cpp",
+      // Recursive UsingValueDecl
+      R"cpp(
+        template <int> class $Class_def[[X]] {
+          template <int> class $Class_def[[Y]] {
+            using $Class[[Y]]<0>::$Unknown_dependentName[[xxx]];
+          };
+        };
+    )cpp"};
   for (const auto &TestCase : TestCases)
     // Mask off scope modifiers to keep the tests manageable.
     // They're tested separately.