[clang] [clang-format] Fix crashes when the macro expansion is empty (PR #119428)

[Owen Pan via cfe-commits]

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@@ -217,6 +219,31 @@ TEST_F(MacroCallReconstructorTest, Identifier) {
   EXPECT_THAT(std::move(Unexp).takeResult(), matchesLine(line(U.consume("X"))));
 }
 
+TEST_F(MacroCallReconstructorTest, IdentifierObject) {
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owenca wrote:

How about`EmptyDefinition` instead of `IdentifierObject`?

https://github.com/llvm/llvm-project/pull/119428