[clang] [Clang][ASTMatcher] Add `dependentNameType` Matcher (PR #121263)

[Amr Hesham via cfe-commits]

https://github.com/AmrDeveloper created https://github.com/llvm/llvm-project/pull/121263

Add AST Matcher for `DependentNameType`

Fixes: https://github.com/llvm/llvm-project/issues/121240

>From 21873d01238f8da0eb0f19656801347400afae65 Mon Sep 17 00:00:00 2001
From: AmrDeveloper <amr96 at programmer.net>
Date: Sat, 28 Dec 2024 13:23:33 +0100
Subject: [PATCH] [Clang][ASTMatcher] Add `dependentNameType` Matcher

---
 clang/docs/LibASTMatchersReference.html           |  9 +++++++++
 clang/docs/ReleaseNotes.rst                       |  2 ++
 clang/include/clang/ASTMatchers/ASTMatchers.h     | 10 ++++++++++
 clang/lib/ASTMatchers/ASTMatchersInternal.cpp     |  1 +
 clang/lib/ASTMatchers/Dynamic/Registry.cpp        |  1 +
 clang/unittests/AST/ASTImporterTest.cpp           |  3 ---
 .../unittests/ASTMatchers/ASTMatchersNodeTest.cpp | 15 +++++++++++++++
 7 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/clang/docs/LibASTMatchersReference.html b/clang/docs/LibASTMatchersReference.html
index ddc99020604c94..69fd43b2114723 100644
--- a/clang/docs/LibASTMatchersReference.html
+++ b/clang/docs/LibASTMatchersReference.html
@@ -2536,6 +2536,15 @@ <h2 id="decl-matchers">Node Matchers</h2>
   matches "decltype(i + j)"
 </pre></td></tr>
 
+<tr><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>></td><td class="name" onclick="toggle('dependentNameType0')"><a name="dependentNameType0Anchor">dependentNameType</a></td><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1DependentNameType.html">DependentNameType</a>>...</td></tr>
+<tr><td colspan="4" class="doc" id="dependentNameType0"><pre>Matches dependent name type.
+
+Example matches T::type
+
+  template <typename T> struct declToImport {
+    typedef typename T::type dependent_name;
+  };
+</pre></td></tr>
 
 <tr><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1Type.html">Type</a>></td><td class="name" onclick="toggle('deducedTemplateSpecializationType0')"><a name="deducedTemplateSpecializationType0Anchor">deducedTemplateSpecializationType</a></td><td>Matcher<<a href="https://clang.llvm.org/doxygen/classclang_1_1DeducedTemplateSpecializationType.html">DeducedTemplateSpecializationType</a>>...</td></tr>
 <tr><td colspan="4" class="doc" id="deducedTemplateSpecializationType0"><pre>Matches C++17 deduced template specialization types, e.g. deduced class
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 983c1da20ed4c8..7446aaf57a02dc 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -1110,6 +1110,8 @@ AST Matchers
 
 - Add ``dependentScopeDeclRefExpr`` matcher to match expressions that refer to dependent scope declarations.
 
+- Add ``dependentNameType`` matcher to match dependent name type.
+
 clang-format
 ------------
 
diff --git a/clang/include/clang/ASTMatchers/ASTMatchers.h b/clang/include/clang/ASTMatchers/ASTMatchers.h
index 22e2546ab81e0a..b27914306b8270 100644
--- a/clang/include/clang/ASTMatchers/ASTMatchers.h
+++ b/clang/include/clang/ASTMatchers/ASTMatchers.h
@@ -7711,6 +7711,16 @@ AST_MATCHER_P(DecayedType, hasDecayedType, internal::Matcher<QualType>,
   return InnerType.matches(Node.getDecayedType(), Finder, Builder);
 }
 
+/// Matches dependent name type
+///
+/// Example matches  T::type
+/// \code
+///  template <typename T> struct declToImport {
+///    typedef typename T::type dependent_name;
+///  };
+/// \endcode
+extern const AstTypeMatcher<DependentNameType> dependentNameType;
+
 /// Matches declarations whose declaration context, interpreted as a
 /// Decl, matches \c InnerMatcher.
 ///
diff --git a/clang/lib/ASTMatchers/ASTMatchersInternal.cpp b/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
index 8c744eebbdfb50..a47633bf4bae24 100644
--- a/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
+++ b/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
@@ -1108,6 +1108,7 @@ const AstTypeMatcher<SubstTemplateTypeParmType> substTemplateTypeParmType;
 const AstTypeMatcher<TemplateTypeParmType> templateTypeParmType;
 const AstTypeMatcher<InjectedClassNameType> injectedClassNameType;
 const AstTypeMatcher<DecayedType> decayedType;
+const AstTypeMatcher<DependentNameType> dependentNameType;
 AST_TYPELOC_TRAVERSE_MATCHER_DEF(hasElementType,
                                  AST_POLYMORPHIC_SUPPORTED_TYPES(ArrayType,
                                                                  ComplexType));
diff --git a/clang/lib/ASTMatchers/Dynamic/Registry.cpp b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
index 685d626d2978bf..674129aee59241 100644
--- a/clang/lib/ASTMatchers/Dynamic/Registry.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
@@ -218,6 +218,7 @@ RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(cxxTryStmt);
   REGISTER_MATCHER(cxxUnresolvedConstructExpr);
   REGISTER_MATCHER(decayedType);
+  REGISTER_MATCHER(dependentNameType);
   REGISTER_MATCHER(decl);
   REGISTER_MATCHER(decompositionDecl);
   REGISTER_MATCHER(declCountIs);
diff --git a/clang/unittests/AST/ASTImporterTest.cpp b/clang/unittests/AST/ASTImporterTest.cpp
index ec062a5cc953b8..ee1d896f1ca6dc 100644
--- a/clang/unittests/AST/ASTImporterTest.cpp
+++ b/clang/unittests/AST/ASTImporterTest.cpp
@@ -3196,9 +3196,6 @@ TEST_P(ImportExpr, DependentScopeDeclRefExpr) {
                  has(callExpr(has(dependentScopeDeclRefExpr())))))))));
 }
 
-const internal::VariadicDynCastAllOfMatcher<Type, DependentNameType>
-    dependentNameType;
-
 TEST_P(ImportExpr, DependentNameType) {
   MatchVerifier<Decl> Verifier;
   testImport("template <typename T> struct declToImport {"
diff --git a/clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp b/clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp
index a3baad367a27b1..0a5ecd29432c5f 100644
--- a/clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp
+++ b/clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp
@@ -1912,6 +1912,21 @@ TEST_P(ASTMatchersTest, DeducedTemplateSpecializationType) {
               deducedTemplateSpecializationType()));
 }
 
+TEST_P(ASTMatchersTest, DependentNameType) {
+   if (!GetParam().isCXX()) {
+    // FIXME: Add a test for `dependentNameType()` that does not depend on C++.
+    return;
+  }
+
+  EXPECT_TRUE(matches(
+      R"(
+        template <typename T> struct declToImport {
+          typedef typename T::type dependent_name;
+        };
+      )",
+   dependentNameType()));
+}
+
 TEST_P(ASTMatchersTest, RecordType) {
   EXPECT_TRUE(matches("struct S {}; struct S s;",
                       recordType(hasDeclaration(recordDecl(hasName("S"))))));