[ASTMatchers] Added hasDirectBase Matcher

Adds a matcher called `hasDirectBase` for matching the `CXXBaseSpecifier` of a class that directly derives from another class. Reviewed By: aaron.ballman Differential Revision: https://reviews.llvm.org/D81552
llvm · Jul 7, 2020 · b0d3ea1 · b0d3ea1
1 parent 52495b9
commit b0d3ea1
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diff --git a/clang/docs/LibASTMatchersReference.html b/clang/docs/LibASTMatchersReference.html
@@ -5658,7 +5658,7 @@ <h2 id="traversal-matchers">AST Traversal Matchers</h2>
 <tr><td colspan="4" class="doc" id="hasAnyBase0"><pre>Matches C++ classes that have a direct or indirect base matching BaseSpecMatcher.
 
 Example:
-matcher hasAnyBase(hasType(cxxRecordDecl(hasName("SpecialBase")))))
+matcher hasAnyBase(hasType(cxxRecordDecl(hasName("SpecialBase"))))
   class Foo;
   class Bar : Foo {};
   class Baz : Bar {};
@@ -5670,6 +5670,20 @@ <h2 id="traversal-matchers">AST Traversal Matchers</h2>
 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CXXRecordDecl.html">CXXRecordDecl</a>&gt;</td><td class="name" onclick="toggle('hasDirectBase0')"><a name="hasDirectBase0Anchor">hasDirectBase</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CXXBaseSpecifier.html">CXXBaseSpecifier</a>&gt; BaseSpecMatcher</td></tr>
+<tr><td colspan="4" class="doc" id="hasDirectBase0"><pre>Matches C++ classes that have a direct base matching BaseSpecMatcher.
+
+Example:
+matcher hasDirectBase(hasType(cxxRecordDecl(hasName("SpecialBase"))))
+  class Foo;
+  class Bar : Foo {};
+  class Baz : Bar {};
+  class SpecialBase;
+  class Proxy : SpecialBase {};  // matches Proxy
+  class IndirectlyDerived : Proxy {};  // doesn't match
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CXXRecordDecl.html">CXXRecordDecl</a>&gt;</td><td class="name" onclick="toggle('hasMethod0')"><a name="hasMethod0Anchor">hasMethod</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CXXMethodDecl.html">CXXMethodDecl</a>&gt; InnerMatcher</td></tr>
 <tr><td colspan="4" class="doc" id="hasMethod0"><pre>Matches the first method of a class or struct that satisfies InnerMatcher.
 

diff --git a/clang/include/clang/ASTMatchers/ASTMatchers.h b/clang/include/clang/ASTMatchers/ASTMatchers.h
@@ -2862,7 +2862,7 @@ AST_POLYMORPHIC_MATCHER_P_OVERLOAD(
 /// BaseSpecMatcher.
 ///
 /// Example:
-/// matcher hasAnyBase(hasType(cxxRecordDecl(hasName("SpecialBase")))))
+/// matcher hasAnyBase(hasType(cxxRecordDecl(hasName("SpecialBase"))))
 /// \code
 ///   class Foo;
 ///   class Bar : Foo {};
@@ -2878,6 +2878,26 @@ AST_MATCHER_P(CXXRecordDecl, hasAnyBase, internal::Matcher<CXXBaseSpecifier>,
   return internal::matchesAnyBase(Node, BaseSpecMatcher, Finder, Builder);
 }
 
+/// Matches C++ classes that have a direct base matching \p BaseSpecMatcher.
+///
+/// Example:
+/// matcher hasDirectBase(hasType(cxxRecordDecl(hasName("SpecialBase"))))
+/// \code
+///   class Foo;
+///   class Bar : Foo {};
+///   class Baz : Bar {};
+///   class SpecialBase;
+///   class Proxy : SpecialBase {};  // matches Proxy
+///   class IndirectlyDerived : Proxy {};  // doesn't match
+/// \endcode
+AST_MATCHER_P(CXXRecordDecl, hasDirectBase, internal::Matcher<CXXBaseSpecifier>,
+              BaseSpecMatcher) {
+  return Node.hasDefinition() &&
+         llvm::any_of(Node.bases(), [&](const CXXBaseSpecifier &Base) {
+           return BaseSpecMatcher.matches(Base, Finder, Builder);
+         });
+}
+
 /// Similar to \c isDerivedFrom(), but also matches classes that directly
 /// match \c Base.
 AST_POLYMORPHIC_MATCHER_P_OVERLOAD(

diff --git a/clang/lib/ASTMatchers/Dynamic/Registry.cpp b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
@@ -278,6 +278,7 @@ RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(hasDefinition);
   REGISTER_MATCHER(hasDescendant);
   REGISTER_MATCHER(hasDestinationType);
+  REGISTER_MATCHER(hasDirectBase);
   REGISTER_MATCHER(hasDynamicExceptionSpec);
   REGISTER_MATCHER(hasEitherOperand);
   REGISTER_MATCHER(hasElementType);

diff --git a/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp b/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
@@ -3125,5 +3125,44 @@ TEST(IsVirtual, NoVirtualBase) {
                          cxxRecordDecl(hasAnyBase(isVirtual()))));
 }
 
+TEST(BaseSpecifier, hasDirectBase) {
+  EXPECT_TRUE(matches(
+      R"cc(
+    class Base {};
+    class Derived : Base{};
+    )cc",
+      cxxRecordDecl(hasName("Derived"),
+                    hasDirectBase(hasType(cxxRecordDecl(hasName("Base")))))));
+
+  StringRef MultiDerived = R"cc(
+    class Base {};
+    class Base2 {};
+    class Derived : Base, Base2{};
+    )cc";
+
+  EXPECT_TRUE(matches(
+      MultiDerived,
+      cxxRecordDecl(hasName("Derived"),
+                    hasDirectBase(hasType(cxxRecordDecl(hasName("Base")))))));
+  EXPECT_TRUE(matches(
+      MultiDerived,
+      cxxRecordDecl(hasName("Derived"),
+                    hasDirectBase(hasType(cxxRecordDecl(hasName("Base2")))))));
+
+  StringRef Indirect = R"cc(
+    class Base {};
+    class Intermediate : Base {};
+    class Derived : Intermediate{};
+    )cc";
+
+  EXPECT_TRUE(
+      matches(Indirect, cxxRecordDecl(hasName("Derived"),
+                                      hasDirectBase(hasType(cxxRecordDecl(
+                                          hasName("Intermediate")))))));
+  EXPECT_TRUE(notMatches(
+      Indirect,
+      cxxRecordDecl(hasName("Derived"),
+                    hasDirectBase(hasType(cxxRecordDecl(hasName("Base")))))));
+}
 } // namespace ast_matchers
 } // namespace clang