[clang] Add AST matcher for initializer list members

Summary:
Much like hasArg for various call expressions, this allows LibTooling users to
match against a member of an initializer list.

This is currently being used as part of the abseil-duration-scale clang-tidy
check.

Differential Revision: https://reviews.llvm.org/D56090

llvm-svn: 350523

1 files changed, 12 insertions, 0 deletions

diff --git a/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp b/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
index d1f949543221..fb17d100c518 100644
--- a/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
+++ b/clang/unittests/ASTMatchers/ASTMatchersNarrowingTest.cpp
@@ -2255,6 +2255,18 @@ TEST(IsAssignmentOperator, Basic) {
       notMatches("void x() { int a; if(a == 0) return; }", BinAsgmtOperator));
 }
 
+TEST(HasInit, Basic) {
+  EXPECT_TRUE(
+    matches("int x{0};",
+            initListExpr(hasInit(0, expr()))));
+  EXPECT_FALSE(
+    matches("int x{0};",
+            initListExpr(hasInit(1, expr()))));
+  EXPECT_FALSE(
+    matches("int x;",
+            initListExpr(hasInit(0, expr()))));
+}
+
 TEST(Matcher, isMain) {
   EXPECT_TRUE(
     matches("int main() {}", functionDecl(isMain())));