Fix structural inequivalency of forward EnumDecl

Summary:
Currently we consider one forward declared RecordDecl and another with a
definition equal. We have to do the same in case of enums.

Reviewers: a_sidorin, r.stahl, xazax.hun

Subscribers: rnkovacs, dkrupp, cfe-commits

Differential Revision: https://reviews.llvm.org/D50444

llvm-svn: 339336
diff --git a/clang/unittests/AST/StructuralEquivalenceTest.cpp b/clang/unittests/AST/StructuralEquivalenceTest.cpp
index 41477dd..7ff7736 100644
--- a/clang/unittests/AST/StructuralEquivalenceTest.cpp
+++ b/clang/unittests/AST/StructuralEquivalenceTest.cpp
@@ -642,6 +642,32 @@
   EXPECT_FALSE(testStructuralMatch(t));
 }
 
+TEST_F(StructuralEquivalenceRecordTest,
+    FwdDeclRecordShouldBeEqualWithFwdDeclRecord) {
+  auto t = makeNamedDecls("class foo;", "class foo;", Lang_CXX11);
+  EXPECT_TRUE(testStructuralMatch(t));
+}
+
+TEST_F(StructuralEquivalenceRecordTest,
+       FwdDeclRecordShouldBeEqualWithRecordWhichHasDefinition) {
+  auto t =
+      makeNamedDecls("class foo;", "class foo { int A; };", Lang_CXX11);
+  EXPECT_TRUE(testStructuralMatch(t));
+}
+
+TEST_F(StructuralEquivalenceRecordTest,
+       RecordShouldBeEqualWithRecordWhichHasDefinition) {
+  auto t = makeNamedDecls("class foo { int A; };", "class foo { int A; };",
+                          Lang_CXX11);
+  EXPECT_TRUE(testStructuralMatch(t));
+}
+
+TEST_F(StructuralEquivalenceRecordTest, RecordsWithDifferentBody) {
+  auto t = makeNamedDecls("class foo { int B; };", "class foo { int A; };",
+                          Lang_CXX11);
+  EXPECT_FALSE(testStructuralMatch(t));
+}
+
 TEST_F(StructuralEquivalenceTest, CompareSameDeclWithMultiple) {
   auto t = makeNamedDecls(
       "struct A{ }; struct B{ }; void foo(A a, A b);",
@@ -650,5 +676,33 @@
   EXPECT_FALSE(testStructuralMatch(t));
 }
 
+struct StructuralEquivalenceEnumTest : StructuralEquivalenceTest {};
+
+TEST_F(StructuralEquivalenceEnumTest, FwdDeclEnumShouldBeEqualWithFwdDeclEnum) {
+  auto t = makeNamedDecls("enum class foo;", "enum class foo;", Lang_CXX11);
+  EXPECT_TRUE(testStructuralMatch(t));
+}
+
+TEST_F(StructuralEquivalenceEnumTest,
+       FwdDeclEnumShouldBeEqualWithEnumWhichHasDefinition) {
+  auto t =
+      makeNamedDecls("enum class foo;", "enum class foo { A };", Lang_CXX11);
+  EXPECT_TRUE(testStructuralMatch(t));
+}
+
+TEST_F(StructuralEquivalenceEnumTest,
+       EnumShouldBeEqualWithEnumWhichHasDefinition) {
+  auto t = makeNamedDecls("enum class foo { A };", "enum class foo { A };",
+                          Lang_CXX11);
+  EXPECT_TRUE(testStructuralMatch(t));
+}
+
+TEST_F(StructuralEquivalenceEnumTest, EnumsWithDifferentBody) {
+  auto t = makeNamedDecls("enum class foo { B };", "enum class foo { A };",
+                          Lang_CXX11);
+  EXPECT_FALSE(testStructuralMatch(t));
+}
+
+
 } // end namespace ast_matchers
 } // end namespace clang