Instantiated methods of ClassTemplateSpecialization are not merged

[martong]

This test fails ATM. The ctor void(int) is instantiated only in the "From" context, but we never merge that, so the unified "To" context has a ctor without the body.

TEST_P(ASTImporterTestBase, MergeCtorOfClassTemplateSpecialization) {
  std::string ClassTemplate =
      R"(
      template <typename T>
      struct X {
          int a{0}; // FieldDecl with InitListExpr
          X(char) : a(3) {}     // (1)
          X(int) {}             // (2)
      };
      )";
  Decl *ToTU = getToTuDecl(ClassTemplate +
      R"(
      void foo() {
          // ClassTemplateSpec with ctor (1): FieldDecl without InitlistExpr
          X<char> xc('c');
      }
      )", Lang_CXX11);
  Decl *FromTU = getTuDecl(ClassTemplate +
      R"(
      void bar() {
          // ClassTemplateSpec with ctor (2): FieldDecl WITH InitlistExpr
          X<char> xc(1);
      }
      )", Lang_CXX11);
  auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
      FromTU, classTemplateSpecializationDecl(hasName("X")));

  auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
  ASSERT_TRUE(ImportedSpec);

  auto CtorPattern =
      cxxConstructorDecl(hasParameter(0, varDecl(hasType(asString("int")))),
                         hasParent(classTemplateSpecializationDecl()));
  auto *FromCtor =
      FirstDeclMatcher<CXXConstructorDecl>().match(FromTU, CtorPattern);
  FromCtor->dump();
  auto *ToCtor =
      FirstDeclMatcher<CXXConstructorDecl>().match(ToTU, CtorPattern);
  ToCtor->dump();
  ASSERT_TRUE(MatchVerifier<CXXConstructorDecl>().match(
      FromCtor, cxxConstructorDecl(has(cxxCtorInitializer()))));
  EXPECT_TRUE(MatchVerifier<CXXConstructorDecl>().match(
      ToCtor, cxxConstructorDecl(has(cxxCtorInitializer()))));
}

[martong]

The same is true for any methods, this test also fails.

TEST_P(ASTImporterTestBase, MergeFunctionOfClassTemplateSpecialization) {
  std::string ClassTemplate =
      R"(
      template <typename T>
      struct X {
        void f() {}
        void g() {}
      };
      )";
  Decl *ToTU = getToTuDecl(ClassTemplate +
      R"(
      void foo() {
          X<char> x;
          x.f();
      }
      )", Lang_CXX11);
  Decl *FromTU = getTuDecl(ClassTemplate +
      R"(
      void bar() {
          X<char> x;
          x.g();
      }
      )", Lang_CXX11);
  auto *FromSpec = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
      FromTU, classTemplateSpecializationDecl(hasName("X")));

  auto *ImportedSpec = Import(FromSpec, Lang_CXX11);
  ASSERT_TRUE(ImportedSpec);

  auto FunPattern = functionDecl(hasName("g"),
                         hasParent(classTemplateSpecializationDecl()));
  auto *FromFun =
      FirstDeclMatcher<FunctionDecl>().match(FromTU, FunPattern);
  FromFun->dump();
  auto *ToFun =
      FirstDeclMatcher<FunctionDecl>().match(ToTU, FunPattern);
  ToFun->dump();
  ASSERT_TRUE(FromFun->hasBody());
  EXPECT_TRUE(ToFun->hasBody());
}