Adding new AST matcher: isConstexpr

It matches constexpr variable and function declarations.

llvm-svn: 238016

clang/include/clang/ASTMatchers/ASTMatchers.h

@@ -2709,6 +2709,23 @@ AST_MATCHER(FunctionDecl, isDeleted) {
   return Node.isDeleted();
 }
 
+/// \brief Matches constexpr variable and function declarations.
+///
+/// Given:
+/// \code
+///   constexpr int foo = 42;
+///   constexpr int bar();
+/// \endcode
+/// varDecl(isConstexpr())
+///   matches the declaration of foo.
+/// functionDecl(isConstexpr())
+///   matches the declaration of bar.
+AST_POLYMORPHIC_MATCHER(isConstexpr,
+                        AST_POLYMORPHIC_SUPPORTED_TYPES(VarDecl,
+                                                        FunctionDecl)) {
+  return Node.isConstexpr();
+}
+
 /// \brief Matches the condition expression of an if statement, for loop,
 /// or conditional operator.
 ///

clang/unittests/ASTMatchers/ASTMatchersTest.cpp

@@ -1595,6 +1595,13 @@ TEST(IsDeleted, MatchesDeletedFunctionDeclarations) {
                       functionDecl(hasName("Func"), isDeleted())));
 }
 
+TEST(isConstexpr, MatchesConstexprDeclarations) {
+  EXPECT_TRUE(matches("constexpr int foo = 42;",
+                      varDecl(hasName("foo"), isConstexpr())));
+  EXPECT_TRUE(matches("constexpr int bar();",
+                      functionDecl(hasName("bar"), isConstexpr())));
+}
+
 TEST(HasAnyParameter, DoesntMatchIfInnerMatcherDoesntMatch) {
   EXPECT_TRUE(notMatches("class Y {}; class X { void x(int) {} };",
       methodDecl(hasAnyParameter(hasType(recordDecl(hasName("X")))))));