[ASTImporter] Add new tests about templated-described swing

[martong]

Summary

Add a new test about importing a partial specialization (of a class). Also,
this patch adds new tests about the templated-described swing, some of these
fail ATM, but subsequent patches will fix them.

[a_sidorin]

Hi Gabor,

Tests are always welcome. This patch is OK and can be committed after fixing nits without additional approval.

unittests/AST/ASTImporterTest.cpp

1097

Broken indentation.

1098

T0 * (missed space)

[martong]

• Clang format the test code snippet.

[martong]

I addressed the comments, thanks for the review!

unittests/AST/ASTImporterTest.cpp

testImport("template <typename T> void declToImport() { T a = 1; }"
                  unless(has(functionDecl(hasName("declToImport"))))))));
   testImport("template <typename T> struct declToImport { T t; };"
              "void instantiate() { declToImport<int>(); }",
              Lang_CXX, "", Lang_CXX, Verifier,
              classTemplateDecl(hasAncestor(translationUnitDecl(
                  unless(has(cxxRecordDecl(hasName("declToImport"))))))));
 }
 
+TEST(ImportDecl, ImportClassTemplatePartialSpecialization) {
+  MatchVerifier<Decl> Verifier;
+  auto Code =
+      R"s(
+    struct declToImport {
+      template <typename T0>
+      struct X;
+       template <typename T0>
+      struct X<T0*> {};
+    };
+    )s";
+  testImport(Code, Lang_CXX, "", Lang_CXX, Verifier,
+             recordDecl(has(classTemplateDecl()),
+                        has(classTemplateSpecializationDecl())));
+}
+
 TEST(ImportExpr, CXXOperatorCallExpr) {
   MatchVerifier<Decl> Verifier;
   testImport("class declToImport {"
              "  void f() { *this = declToImport(); }"
              "};",
              Lang_CXX, "", Lang_CXX, Verifier,
              cxxRecordDecl(has(cxxMethodDecl(hasBody(compoundStmt(
                  has(exprWithCleanups(has(cxxOperatorCallExpr())))))))));
TEST_P(ASTImporterTestBase, ImportOfTemplatedDeclOfClassTemplateDecl) {
   auto To = cast<ClassTemplateDecl>(Import(From, Lang_CXX));
   ASSERT_TRUE(To);
   Decl *ToTemplated = To->getTemplatedDecl();
   Decl *ToTemplated1 = Import(From->getTemplatedDecl(), Lang_CXX);
   EXPECT_TRUE(ToTemplated1);
   EXPECT_EQ(ToTemplated1, ToTemplated);
 }
 
+TEST_P(ASTImporterTestBase,
+       DISABLED_ImportOfTemplatedDeclOfFunctionTemplateDecl) {
+  Decl *FromTU = getTuDecl("template<class X> void f(){}", Lang_CXX);
+  auto From = FirstDeclMatcher<FunctionTemplateDecl>().match(
+      FromTU, functionTemplateDecl());
+  ASSERT_TRUE(From);
+  auto To = cast<FunctionTemplateDecl>(Import(From, Lang_CXX));
+  ASSERT_TRUE(To);
+  Decl *ToTemplated = To->getTemplatedDecl();
+  Decl *ToTemplated1 = Import(From->getTemplatedDecl(), Lang_CXX);
+  EXPECT_TRUE(ToTemplated1);
+  EXPECT_EQ(ToTemplated1, ToTemplated);
+}
+
+TEST_P(ASTImporterTestBase,
+       ImportOfTemplatedDeclShouldImportTheClassTemplateDecl) {
+  Decl *FromTU = getTuDecl("template<class X> struct S{};", Lang_CXX);
+  auto FromFT =
+      FirstDeclMatcher<ClassTemplateDecl>().match(FromTU, classTemplateDecl());
+  ASSERT_TRUE(FromFT);
+
+  auto ToTemplated =
+      cast<CXXRecordDecl>(Import(FromFT->getTemplatedDecl(), Lang_CXX));
+  EXPECT_TRUE(ToTemplated);
+  auto ToTU = ToTemplated->getTranslationUnitDecl();
+  auto ToFT =
+      FirstDeclMatcher<ClassTemplateDecl>().match(ToTU, classTemplateDecl());
+  EXPECT_TRUE(ToFT);
+}
+
+TEST_P(ASTImporterTestBase,
+       DISABLED_ImportOfTemplatedDeclShouldImportTheFunctionTemplateDecl) {
+  Decl *FromTU = getTuDecl("template<class X> void f(){}", Lang_CXX);
+  auto FromFT = FirstDeclMatcher<FunctionTemplateDecl>().match(
+      FromTU, functionTemplateDecl());
+  ASSERT_TRUE(FromFT);
+
+  auto ToTemplated =
+      cast<FunctionDecl>(Import(FromFT->getTemplatedDecl(), Lang_CXX));
+  EXPECT_TRUE(ToTemplated);
+  auto ToTU = ToTemplated->getTranslationUnitDecl();
+  auto ToFT = FirstDeclMatcher<FunctionTemplateDecl>().match(
+      ToTU, functionTemplateDecl());
+  EXPECT_TRUE(ToFT);
+}
+
 TEST_P(ASTImporterTestBase, ImportCorrectTemplatedDecl) {
   auto Code =
         R"(
         namespace x {
           template<class X> struct S1{};
           template<class X> struct S2{};
           template<class X> struct S3{};
         }