[ASTMatchers] overload ignoringParens for Expr

Summary: This patch allows fixing PR39583.

Reviewers: aaron.ballman, sbenza, klimek

Reviewed By: aaron.ballman

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D54307

llvm-svn: 346554

clang/docs/LibASTMatchersReference.html

@@ -5552,6 +5552,17 @@ <h2 id="traversal-matchers">AST Traversal Matchers</h2>
 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Expr.html">Expr</a>&gt;</td><td class="name" onclick="toggle('ignoringParens1')"><a name="ignoringParens1Anchor">ignoringParens</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Expr.html">Expr</a>&gt; InnerMatcher</td></tr>
+<tr><td colspan="4" class="doc" id="ignoringParens1"><pre>Overload ignoringParens for Expr.
+
+Given
+  const char* str = ("my-string");
+The matcher
+  implicitCastExpr(hasSourceExpression(ignoringParens(stringLiteral())))
+would match the implicit cast resulting from the assignment.
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1FieldDecl.html">FieldDecl</a>&gt;</td><td class="name" onclick="toggle('hasInClassInitializer0')"><a name="hasInClassInitializer0Anchor">hasInClassInitializer</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Expr.html">Expr</a>&gt; InnerMatcher</td></tr>
 <tr><td colspan="4" class="doc" id="hasInClassInitializer0"><pre>Matches non-static data members that have an in-class initializer.
 

clang/include/clang/ASTMatchers/ASTMatchers.h

@@ -811,11 +811,28 @@ AST_MATCHER_P(Expr, ignoringParenImpCasts,
 ///   varDecl(hasType(pointerType(pointee(ignoringParens(functionType())))))
 /// \endcode
 /// would match the declaration for fp.
-AST_MATCHER_P(QualType, ignoringParens,
-              internal::Matcher<QualType>, InnerMatcher) {
+AST_MATCHER_P_OVERLOAD(QualType, ignoringParens, internal::Matcher<QualType>,
+                       InnerMatcher, 0) {
   return InnerMatcher.matches(Node.IgnoreParens(), Finder, Builder);
 }
 
+/// Overload \c ignoringParens for \c Expr.
+///
+/// Given
+/// \code
+///   const char* str = ("my-string");
+/// \endcode
+/// The matcher
+/// \code
+///   implicitCastExpr(hasSourceExpression(ignoringParens(stringLiteral())))
+/// \endcode
+/// would match the implicit cast resulting from the assignment.
+AST_MATCHER_P_OVERLOAD(Expr, ignoringParens, internal::Matcher<Expr>,
+                       InnerMatcher, 1) {
+  const Expr *E = Node.IgnoreParens();
+  return InnerMatcher.matches(*E, Finder, Builder);
+}
+
 /// Matches expressions that are instantiation-dependent even if it is
 /// neither type- nor value-dependent.
 ///

clang/lib/ASTMatchers/Dynamic/Registry.cpp

@@ -106,6 +106,7 @@ RegistryMaps::RegistryMaps() {
   REGISTER_OVERLOADED_2(callee);
   REGISTER_OVERLOADED_2(hasPrefix);
   REGISTER_OVERLOADED_2(hasType);
+  REGISTER_OVERLOADED_2(ignoringParens);
   REGISTER_OVERLOADED_2(isDerivedFrom);
   REGISTER_OVERLOADED_2(isSameOrDerivedFrom);
   REGISTER_OVERLOADED_2(loc);
@@ -318,7 +319,6 @@ RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(ignoringImplicit);
   REGISTER_MATCHER(ignoringParenCasts);
   REGISTER_MATCHER(ignoringParenImpCasts);
-  REGISTER_MATCHER(ignoringParens);
   REGISTER_MATCHER(imaginaryLiteral);
   REGISTER_MATCHER(implicitCastExpr);
   REGISTER_MATCHER(implicitValueInitExpr);

clang/unittests/ASTMatchers/ASTMatchersNodeTest.cpp

@@ -1147,6 +1147,14 @@ TEST(ParenExpression, SimpleCases) {
                          parenExpr()));
 }
 
+TEST(ParenExpression, IgnoringParens) {
+  EXPECT_FALSE(matches("const char* str = (\"my-string\");",
+                       implicitCastExpr(hasSourceExpression(stringLiteral()))));
+  EXPECT_TRUE(matches(
+      "const char* str = (\"my-string\");",
+      implicitCastExpr(hasSourceExpression(ignoringParens(stringLiteral())))));
+}
+
 TEST(TypeMatching, MatchesTypes) {
   EXPECT_TRUE(matches("struct S {};", qualType().bind("loc")));
 }