unittests/AST/ASTImporterTest.cpp

//===- unittest/AST/ASTImporterTest.cpp - AST node import test ------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Tests for the correct import of AST nodes from one AST context to another.
//
//===----------------------------------------------------------------------===//

#include "llvm/ADT/StringMap.h"

#include "clang/AST/DeclContextInternals.h"

#include "ASTImporterFixtures.h"
#include "MatchVerifier.h"

namespace clang {
namespace ast_matchers {

using internal::Matcher;
using internal::BindableMatcher;
using llvm::StringMap;

// Base class for those tests which use the family of `testImport` functions.
class TestImportBase : public CompilerOptionSpecificTest,
                       public ::testing::WithParamInterface<ArgVector> {

  template <typename NodeType>
  llvm::Expected<NodeType> importNode(ASTUnit *From, ASTUnit *To,
                                      ASTImporter &Importer, NodeType Node) {
    ASTContext &ToCtx = To->getASTContext();

    // Add 'From' file to virtual file system so importer can 'find' it
    // while importing SourceLocations. It is safe to add same file multiple
    // times - it just isn't replaced.
    StringRef FromFileName = From->getMainFileName();
    createVirtualFileIfNeeded(To, FromFileName,
                              From->getBufferForFile(FromFileName));

    auto Imported = Importer.Import(Node);

    if (Imported) {
      // This should dump source locations and assert if some source locations
      // were not imported.
      SmallString<1024> ImportChecker;
      llvm::raw_svector_ostream ToNothing(ImportChecker);
      ToCtx.getTranslationUnitDecl()->print(ToNothing);

      // This traverses the AST to catch certain bugs like poorly or not
      // implemented subtrees.
      (*Imported)->dump(ToNothing);
    }

    return Imported;
  }

  template <typename NodeType>
  testing::AssertionResult
  testImport(const std::string &FromCode, const ArgVector &FromArgs,
             const std::string &ToCode, const ArgVector &ToArgs,
             MatchVerifier<NodeType> &Verifier,
             const BindableMatcher<NodeType> &SearchMatcher,
             const BindableMatcher<NodeType> &VerificationMatcher) {
    const char *const InputFileName = "input.cc";
    const char *const OutputFileName = "output.cc";

    std::unique_ptr<ASTUnit> FromAST = tooling::buildASTFromCodeWithArgs(
                                 FromCode, FromArgs, InputFileName),
                             ToAST = tooling::buildASTFromCodeWithArgs(
                                 ToCode, ToArgs, OutputFileName);

    ASTContext &FromCtx = FromAST->getASTContext(),
               &ToCtx = ToAST->getASTContext();

    ASTImporter Importer(ToCtx, ToAST->getFileManager(), FromCtx,
                         FromAST->getFileManager(), false);

    auto FoundNodes = match(SearchMatcher, FromCtx);
    if (FoundNodes.size() != 1)
      return testing::AssertionFailure()
             << "Multiple potential nodes were found!";

    auto ToImport = selectFirst<NodeType>(DeclToImportID, FoundNodes);
    if (!ToImport)
      return testing::AssertionFailure() << "Node type mismatch!";

    // Sanity check: the node being imported should match in the same way as
    // the result node.
    BindableMatcher<NodeType> WrapperMatcher(VerificationMatcher);
    EXPECT_TRUE(Verifier.match(ToImport, WrapperMatcher));

    auto Imported = importNode(FromAST.get(), ToAST.get(), Importer, ToImport);
    if (!Imported) {
      std::string ErrorText;
      handleAllErrors(
          Imported.takeError(),
          [&ErrorText](const ImportError &Err) { ErrorText = Err.message(); });
      return testing::AssertionFailure()
             << "Import failed, error: \"" << ErrorText << "\"!";
    }

    return Verifier.match(*Imported, WrapperMatcher);
  }

  template <typename NodeType>
  testing::AssertionResult
  testImport(const std::string &FromCode, const ArgVector &FromArgs,
             const std::string &ToCode, const ArgVector &ToArgs,
             MatchVerifier<NodeType> &Verifier,
             const BindableMatcher<NodeType> &VerificationMatcher) {
    return testImport(
        FromCode, FromArgs, ToCode, ToArgs, Verifier,
        translationUnitDecl(
            has(namedDecl(hasName(DeclToImportID)).bind(DeclToImportID))),
        VerificationMatcher);
  }

protected:
  ArgVector getExtraArgs() const override { return GetParam(); }

public:

  /// Test how AST node named "declToImport" located in the translation unit
  /// of "FromCode" virtual file is imported to "ToCode" virtual file.
  /// The verification is done by running AMatcher over the imported node.
  template <typename NodeType, typename MatcherType>
  void testImport(const std::string &FromCode, Language FromLang,
                  const std::string &ToCode, Language ToLang,
                  MatchVerifier<NodeType> &Verifier,
                  const MatcherType &AMatcher) {
    ArgVector FromArgs = getArgVectorForLanguage(FromLang),
              ToArgs = getArgVectorForLanguage(ToLang);
    EXPECT_TRUE(
        testImport(FromCode, FromArgs, ToCode, ToArgs, Verifier, AMatcher));
  }

  struct ImportAction {
    StringRef FromFilename;
    StringRef ToFilename;
    // FIXME: Generalize this to support other node kinds.
    BindableMatcher<Decl> ImportPredicate;

    ImportAction(StringRef FromFilename, StringRef ToFilename,
                 DeclarationMatcher ImportPredicate)
        : FromFilename(FromFilename), ToFilename(ToFilename),
          ImportPredicate(ImportPredicate) {}

    ImportAction(StringRef FromFilename, StringRef ToFilename,
                 const std::string &DeclName)
        : FromFilename(FromFilename), ToFilename(ToFilename),
          ImportPredicate(namedDecl(hasName(DeclName))) {}
  };

  using SingleASTUnit = std::unique_ptr<ASTUnit>;
  using AllASTUnits = StringMap<SingleASTUnit>;

  struct CodeEntry {
    std::string CodeSample;
    Language Lang;
  };

  using CodeFiles = StringMap<CodeEntry>;

  /// Builds an ASTUnit for one potential compile options set.
  SingleASTUnit createASTUnit(StringRef FileName, const CodeEntry &CE) const {
    ArgVector Args = getArgVectorForLanguage(CE.Lang);
    auto AST = tooling::buildASTFromCodeWithArgs(CE.CodeSample, Args, FileName);
    EXPECT_TRUE(AST.get());
    return AST;
  }

  /// Test an arbitrary sequence of imports for a set of given in-memory files.
  /// The verification is done by running VerificationMatcher against a
  /// specified AST node inside of one of given files.
  /// \param CodeSamples Map whose key is the file name and the value is the
  /// file content.
  /// \param ImportActions Sequence of imports. Each import in sequence
  /// specifies "from file" and "to file" and a matcher that is used for
  /// searching a declaration for import in "from file".
  /// \param FileForFinalCheck Name of virtual file for which the final check is
  /// applied.
  /// \param FinalSelectPredicate Matcher that specifies the AST node in the
  /// FileForFinalCheck for which the verification will be done.
  /// \param VerificationMatcher Matcher that will be used for verification
  /// after all imports in sequence are done.
  void testImportSequence(const CodeFiles &CodeSamples,
                          const std::vector<ImportAction> &ImportActions,
                          StringRef FileForFinalCheck,
                          BindableMatcher<Decl> FinalSelectPredicate,
                          BindableMatcher<Decl> VerificationMatcher) {
    AllASTUnits AllASTs;
    using ImporterKey = std::pair<const ASTUnit *, const ASTUnit *>;
    llvm::DenseMap<ImporterKey, std::unique_ptr<ASTImporter>> Importers;

    auto GenASTsIfNeeded = [this, &AllASTs, &CodeSamples](StringRef Filename) {
      if (!AllASTs.count(Filename)) {
        auto Found = CodeSamples.find(Filename);
        assert(Found != CodeSamples.end() && "Wrong file for import!");
        AllASTs[Filename] = createASTUnit(Filename, Found->getValue());
      }
    };

    for (const ImportAction &Action : ImportActions) {
      StringRef FromFile = Action.FromFilename, ToFile = Action.ToFilename;
      GenASTsIfNeeded(FromFile);
      GenASTsIfNeeded(ToFile);

      ASTUnit *From = AllASTs[FromFile].get();
      ASTUnit *To = AllASTs[ToFile].get();

      // Create a new importer if needed.
      std::unique_ptr<ASTImporter> &ImporterRef = Importers[{From, To}];
      if (!ImporterRef)
        ImporterRef.reset(new ASTImporter(
            To->getASTContext(), To->getFileManager(), From->getASTContext(),
            From->getFileManager(), false));

      // Find the declaration and import it.
      auto FoundDecl = match(Action.ImportPredicate.bind(DeclToImportID),
                             From->getASTContext());
      EXPECT_TRUE(FoundDecl.size() == 1);
      const Decl *ToImport = selectFirst<Decl>(DeclToImportID, FoundDecl);
      auto Imported = importNode(From, To, *ImporterRef, ToImport);
      EXPECT_TRUE(static_cast<bool>(Imported));
      if (!Imported)
        llvm::consumeError(Imported.takeError());
    }

    // Find the declaration and import it.
    auto FoundDecl = match(FinalSelectPredicate.bind(DeclToVerifyID),
                           AllASTs[FileForFinalCheck]->getASTContext());
    EXPECT_TRUE(FoundDecl.size() == 1);
    const Decl *ToVerify = selectFirst<Decl>(DeclToVerifyID, FoundDecl);
    MatchVerifier<Decl> Verifier;
    EXPECT_TRUE(
        Verifier.match(ToVerify, BindableMatcher<Decl>(VerificationMatcher)));
  }
};

template <typename T> RecordDecl *getRecordDecl(T *D) {
  auto *ET = cast<ElaboratedType>(D->getType().getTypePtr());
  return cast<RecordType>(ET->getNamedType().getTypePtr())->getDecl();
}

struct ImportExpr : TestImportBase {};
struct ImportType : TestImportBase {};
struct ImportDecl : TestImportBase {};

struct CanonicalRedeclChain : ASTImporterOptionSpecificTestBase {};

TEST_P(CanonicalRedeclChain, ShouldBeConsequentWithMatchers) {
  Decl *FromTU = getTuDecl("void f();", Lang_CXX);
  auto Pattern = functionDecl(hasName("f"));
  auto *D0 = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);

  auto Redecls = getCanonicalForwardRedeclChain(D0);
  ASSERT_EQ(Redecls.size(), 1u);
  EXPECT_EQ(D0, Redecls[0]);
}

TEST_P(CanonicalRedeclChain, ShouldBeConsequentWithMatchers2) {
  Decl *FromTU = getTuDecl("void f(); void f(); void f();", Lang_CXX);
  auto Pattern = functionDecl(hasName("f"));
  auto *D0 = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
  auto *D2 = LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
  FunctionDecl *D1 = D2->getPreviousDecl();

  auto Redecls = getCanonicalForwardRedeclChain(D0);
  ASSERT_EQ(Redecls.size(), 3u);
  EXPECT_EQ(D0, Redecls[0]);
  EXPECT_EQ(D1, Redecls[1]);
  EXPECT_EQ(D2, Redecls[2]);
}

TEST_P(CanonicalRedeclChain, ShouldBeSameForAllDeclInTheChain) {
  Decl *FromTU = getTuDecl("void f(); void f(); void f();", Lang_CXX);
  auto Pattern = functionDecl(hasName("f"));
  auto *D0 = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
  auto *D2 = LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
  FunctionDecl *D1 = D2->getPreviousDecl();

  auto RedeclsD0 = getCanonicalForwardRedeclChain(D0);
  auto RedeclsD1 = getCanonicalForwardRedeclChain(D1);
  auto RedeclsD2 = getCanonicalForwardRedeclChain(D2);

  EXPECT_THAT(RedeclsD0, ::testing::ContainerEq(RedeclsD1));
  EXPECT_THAT(RedeclsD1, ::testing::ContainerEq(RedeclsD2));
}

namespace {
struct RedirectingImporter : public ASTImporter {
  using ASTImporter::ASTImporter;

protected:
  llvm::Expected<Decl *> ImportImpl(Decl *FromD) override {
    auto *ND = dyn_cast<NamedDecl>(FromD);
    if (!ND || ND->getName() != "shouldNotBeImported")
      return ASTImporter::ImportImpl(FromD);
    for (Decl *D : getToContext().getTranslationUnitDecl()->decls()) {
      if (auto *ND = dyn_cast<NamedDecl>(D))
        if (ND->getName() == "realDecl") {
          RegisterImportedDecl(FromD, ND);
          return ND;
        }
    }
    return ASTImporter::ImportImpl(FromD);
  }
};

} // namespace

struct RedirectingImporterTest : ASTImporterOptionSpecificTestBase {
  RedirectingImporterTest() {
    Creator = [](ASTContext &ToContext, FileManager &ToFileManager,
                 ASTContext &FromContext, FileManager &FromFileManager,
                 bool MinimalImport,
                 const std::shared_ptr<ASTImporterSharedState> &SharedState) {
      return new RedirectingImporter(ToContext, ToFileManager, FromContext,
                                     FromFileManager, MinimalImport,
                                     SharedState);
    };
  }
};

// Test that an ASTImporter subclass can intercept an import call.
TEST_P(RedirectingImporterTest, InterceptImport) {
  Decl *From, *To;
  std::tie(From, To) =
      getImportedDecl("class shouldNotBeImported {};", Lang_CXX,
                      "class realDecl {};", Lang_CXX, "shouldNotBeImported");
  auto *Imported = cast<CXXRecordDecl>(To);
  EXPECT_EQ(Imported->getQualifiedNameAsString(), "realDecl");

  // Make sure our importer prevented the importing of the decl.
  auto *ToTU = Imported->getTranslationUnitDecl();
  auto Pattern = functionDecl(hasName("shouldNotBeImported"));
  unsigned count =
      DeclCounterWithPredicate<CXXRecordDecl>().match(ToTU, Pattern);
  EXPECT_EQ(0U, count);
}

// Test that when we indirectly import a declaration the custom ASTImporter
// is still intercepting the import.
TEST_P(RedirectingImporterTest, InterceptIndirectImport) {
  Decl *From, *To;
  std::tie(From, To) =
      getImportedDecl("class shouldNotBeImported {};"
                      "class F { shouldNotBeImported f; };",
                      Lang_CXX, "class realDecl {};", Lang_CXX, "F");

  // Make sure our ASTImporter prevented the importing of the decl.
  auto *ToTU = To->getTranslationUnitDecl();
  auto Pattern = functionDecl(hasName("shouldNotBeImported"));
  unsigned count =
      DeclCounterWithPredicate<CXXRecordDecl>().match(ToTU, Pattern);
  EXPECT_EQ(0U, count);
}

struct ImportPath : ASTImporterOptionSpecificTestBase {
  Decl *FromTU;
  FunctionDecl *D0, *D1, *D2;
  ImportPath() {
    FromTU = getTuDecl("void f(); void f(); void f();", Lang_CXX);
    auto Pattern = functionDecl(hasName("f"));
    D0 = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
    D2 = LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
    D1 = D2->getPreviousDecl();
  }
};

TEST_P(ImportPath, Push) {
  ASTImporter::ImportPathTy path;
  path.push(D0);
  EXPECT_FALSE(path.hasCycleAtBack());
}

TEST_P(ImportPath, SmallCycle) {
  ASTImporter::ImportPathTy path;
  path.push(D0);
  path.push(D0);
  EXPECT_TRUE(path.hasCycleAtBack());
  path.pop();
  EXPECT_FALSE(path.hasCycleAtBack());
  path.push(D0);
  EXPECT_TRUE(path.hasCycleAtBack());
}

TEST_P(ImportPath, GetSmallCycle) {
  ASTImporter::ImportPathTy path;
  path.push(D0);
  path.push(D0);
  EXPECT_TRUE(path.hasCycleAtBack());
  std::array<Decl* ,2> Res;
  int i = 0;
  for (Decl *Di : path.getCycleAtBack()) {
    Res[i++] = Di;
  }
  ASSERT_EQ(i, 2);
  EXPECT_EQ(Res[0], D0);
  EXPECT_EQ(Res[1], D0);
}

TEST_P(ImportPath, GetCycle) {
  ASTImporter::ImportPathTy path;
  path.push(D0);
  path.push(D1);
  path.push(D2);
  path.push(D0);
  EXPECT_TRUE(path.hasCycleAtBack());
  std::array<Decl* ,4> Res;
  int i = 0;
  for (Decl *Di : path.getCycleAtBack()) {
    Res[i++] = Di;
  }
  ASSERT_EQ(i, 4);
  EXPECT_EQ(Res[0], D0);
  EXPECT_EQ(Res[1], D2);
  EXPECT_EQ(Res[2], D1);
  EXPECT_EQ(Res[3], D0);
}

TEST_P(ImportPath, CycleAfterCycle) {
  ASTImporter::ImportPathTy path;
  path.push(D0);
  path.push(D1);
  path.push(D0);
  path.push(D1);
  path.push(D2);
  path.push(D0);
  EXPECT_TRUE(path.hasCycleAtBack());
  std::array<Decl* ,4> Res;
  int i = 0;
  for (Decl *Di : path.getCycleAtBack()) {
    Res[i++] = Di;
  }
  ASSERT_EQ(i, 4);
  EXPECT_EQ(Res[0], D0);
  EXPECT_EQ(Res[1], D2);
  EXPECT_EQ(Res[2], D1);
  EXPECT_EQ(Res[3], D0);

  path.pop();
  path.pop();
  path.pop();
  EXPECT_TRUE(path.hasCycleAtBack());
  i = 0;
  for (Decl *Di : path.getCycleAtBack()) {
    Res[i++] = Di;
  }
  ASSERT_EQ(i, 3);
  EXPECT_EQ(Res[0], D0);
  EXPECT_EQ(Res[1], D1);
  EXPECT_EQ(Res[2], D0);

  path.pop();
  EXPECT_FALSE(path.hasCycleAtBack());
}

TEST_P(ImportExpr, ImportStringLiteral) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { (void)\"foo\"; }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          stringLiteral(hasType(asString("const char [4]"))))));
  testImport(
      "void declToImport() { (void)L\"foo\"; }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          stringLiteral(hasType(asString("const wchar_t [4]"))))));
  testImport(
      "void declToImport() { (void) \"foo\" \"bar\"; }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          stringLiteral(hasType(asString("const char [7]"))))));
}

TEST_P(ImportExpr, ImportChooseExpr) {
  MatchVerifier<Decl> Verifier;

  // This case tests C code that is not condition-dependent and has a true
  // condition.
  testImport(
    "void declToImport() { (void)__builtin_choose_expr(1, 2, 3); }",
    Lang_C, "", Lang_C, Verifier,
    functionDecl(hasDescendant(chooseExpr())));
}

TEST_P(ImportExpr, ImportGNUNullExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { (void)__null; }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(gnuNullExpr(hasType(isInteger())))));
}

TEST_P(ImportExpr, ImportCXXNullPtrLiteralExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { (void)nullptr; }",
      Lang_CXX11, "", Lang_CXX11, Verifier,
      functionDecl(hasDescendant(cxxNullPtrLiteralExpr())));
}


TEST_P(ImportExpr, ImportFloatinglLiteralExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { (void)1.0; }",
      Lang_C, "", Lang_C, Verifier,
      functionDecl(hasDescendant(
          floatLiteral(equals(1.0), hasType(asString("double"))))));
  testImport(
      "void declToImport() { (void)1.0e-5f; }",
      Lang_C, "", Lang_C, Verifier,
      functionDecl(hasDescendant(
          floatLiteral(equals(1.0e-5f), hasType(asString("float"))))));
}

TEST_P(ImportExpr, ImportImaginaryLiteralExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { (void)1.0i; }",
      Lang_CXX14, "", Lang_CXX14, Verifier,
      functionDecl(hasDescendant(imaginaryLiteral())));
}

TEST_P(ImportExpr, ImportCompoundLiteralExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() {"
      "  struct s { int x; long y; unsigned z; }; "
      "  (void)(struct s){ 42, 0L, 1U }; }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          compoundLiteralExpr(
              hasType(asString("struct s")),
              has(initListExpr(
                  hasType(asString("struct s")),
                  has(integerLiteral(
                      equals(42), hasType(asString("int")))),
                  has(integerLiteral(
                      equals(0), hasType(asString("long")))),
                  has(integerLiteral(
                      equals(1), hasType(asString("unsigned int"))))))))));
}

TEST_P(ImportExpr, ImportCXXThisExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "class declToImport { void f() { (void)this; } };",
      Lang_CXX, "", Lang_CXX, Verifier,
      cxxRecordDecl(
          hasMethod(
              hasDescendant(
                  cxxThisExpr(
                      hasType(
                          asString("class declToImport *")))))));
}

TEST_P(ImportExpr, ImportAtomicExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { int *ptr; __atomic_load_n(ptr, 1); }",
      Lang_C, "", Lang_C, Verifier,
      functionDecl(hasDescendant(
          atomicExpr(
              has(ignoringParenImpCasts(
                  declRefExpr(hasDeclaration(varDecl(hasName("ptr"))),
                      hasType(asString("int *"))))),
              has(integerLiteral(equals(1), hasType(asString("int"))))))));
}

TEST_P(ImportExpr, ImportLabelDeclAndAddrLabelExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { loop: goto loop; (void)&&loop; }",
      Lang_C, "", Lang_C, Verifier,
      functionDecl(
          hasDescendant(
              labelStmt(hasDeclaration(labelDecl(hasName("loop"))))),
          hasDescendant(
              addrLabelExpr(hasDeclaration(labelDecl(hasName("loop")))))));
}

AST_MATCHER_P(TemplateDecl, hasTemplateDecl,
              internal::Matcher<NamedDecl>, InnerMatcher) {
  const NamedDecl *Template = Node.getTemplatedDecl();
  return Template && InnerMatcher.matches(*Template, Finder, Builder);
}

TEST_P(ImportExpr, ImportParenListExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template<typename T> class dummy { void f() { dummy X(*this); } };"
      "typedef dummy<int> declToImport;"
      "template class dummy<int>;",
      Lang_CXX, "", Lang_CXX, Verifier,
      typedefDecl(hasType(templateSpecializationType(
          hasDeclaration(classTemplateSpecializationDecl(hasSpecializedTemplate(
              classTemplateDecl(hasTemplateDecl(cxxRecordDecl(hasMethod(allOf(
                  hasName("f"),
                  hasBody(compoundStmt(has(declStmt(hasSingleDecl(
                      varDecl(hasInitializer(parenListExpr(has(unaryOperator(
                          hasOperatorName("*"),
                          hasUnaryOperand(cxxThisExpr())))))))))))))))))))))));
}

TEST_P(ImportExpr, ImportSwitch) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { int b; switch (b) { case 1: break; } }",
      Lang_C, "", Lang_C, Verifier,
      functionDecl(hasDescendant(
          switchStmt(has(compoundStmt(has(caseStmt())))))));
}

TEST_P(ImportExpr, ImportStmtExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
    "void declToImport() { int b; int a = b ?: 1; int C = ({int X=4; X;}); }",
    Lang_C, "", Lang_C, Verifier,
    functionDecl(hasDescendant(
        varDecl(
            hasName("C"),
            hasType(asString("int")),
            hasInitializer(
                stmtExpr(
                    hasAnySubstatement(declStmt(hasSingleDecl(
                        varDecl(
                            hasName("X"),
                            hasType(asString("int")),
                            hasInitializer(
                                integerLiteral(equals(4))))))),
                    hasDescendant(
                        implicitCastExpr())))))));
}

TEST_P(ImportExpr, ImportConditionalOperator) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { (void)(true ? 1 : -5); }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          conditionalOperator(
              hasCondition(cxxBoolLiteral(equals(true))),
              hasTrueExpression(integerLiteral(equals(1))),
              hasFalseExpression(
                  unaryOperator(hasUnaryOperand(integerLiteral(equals(5))))))
          )));
}

TEST_P(ImportExpr, ImportBinaryConditionalOperator) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { (void)(1 ?: -5); }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          binaryConditionalOperator(
              hasCondition(
                  implicitCastExpr(
                      hasSourceExpression(opaqueValueExpr(
                          hasSourceExpression(integerLiteral(equals(1))))),
                      hasType(booleanType()))),
              hasTrueExpression(
                  opaqueValueExpr(
                      hasSourceExpression(integerLiteral(equals(1))))),
              hasFalseExpression(
                  unaryOperator(
                      hasOperatorName("-"),
                      hasUnaryOperand(integerLiteral(equals(5)))))))));
}

TEST_P(ImportExpr, ImportDesignatedInitExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() {"
      "  struct point { double x; double y; };"
      "  struct point ptarray[10] = "
      "{ [2].y = 1.0, [2].x = 2.0, [0].x = 1.0 }; }",
      Lang_C, "", Lang_C, Verifier,
      functionDecl(hasDescendant(
          initListExpr(
              has(designatedInitExpr(
                  designatorCountIs(2),
                  hasDescendant(floatLiteral(equals(1.0))),
                  hasDescendant(integerLiteral(equals(2))))),
              has(designatedInitExpr(
                  designatorCountIs(2),
                  hasDescendant(floatLiteral(equals(2.0))),
                  hasDescendant(integerLiteral(equals(2))))),
              has(designatedInitExpr(
                  designatorCountIs(2),
                  hasDescendant(floatLiteral(equals(1.0))),
                  hasDescendant(integerLiteral(equals(0)))))))));
}

TEST_P(ImportExpr, ImportPredefinedExpr) {
  MatchVerifier<Decl> Verifier;
  // __func__ expands as StringLiteral("declToImport")
  testImport(
      "void declToImport() { (void)__func__; }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          predefinedExpr(
              hasType(
                  asString("const char [13]")),
              has(stringLiteral(hasType(
                  asString("const char [13]"))))))));
}

TEST_P(ImportExpr, ImportInitListExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() {"
      "  struct point { double x; double y; };"
      "  point ptarray[10] = { [2].y = 1.0, [2].x = 2.0,"
      "                        [0].x = 1.0 }; }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          initListExpr(
              has(
                  cxxConstructExpr(
                  requiresZeroInitialization())),
              has(
                  initListExpr(
                      hasType(asString("struct point")),
                      has(floatLiteral(equals(1.0))),
                      has(implicitValueInitExpr(
                          hasType(asString("double")))))),
              has(
                  initListExpr(
                      hasType(asString("struct point")),
                      has(floatLiteral(equals(2.0))),
                      has(floatLiteral(equals(1.0)))))))));
}


const internal::VariadicDynCastAllOfMatcher<Expr, VAArgExpr> vaArgExpr;

TEST_P(ImportExpr, ImportVAArgExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport(__builtin_va_list list, ...) {"
      "  (void)__builtin_va_arg(list, int); }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          cStyleCastExpr(hasSourceExpression(vaArgExpr())))));
}

TEST_P(ImportExpr, CXXTemporaryObjectExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "struct C {};"
      "void declToImport() { C c = C(); }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          exprWithCleanups(has(cxxConstructExpr(
              has(materializeTemporaryExpr(has(implicitCastExpr(
                  has(cxxTemporaryObjectExpr())))))))))));
}

TEST_P(ImportType, ImportAtomicType) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { typedef _Atomic(int) a_int; }",
      Lang_CXX11, "", Lang_CXX11, Verifier,
      functionDecl(hasDescendant(typedefDecl(has(atomicType())))));
}

TEST_P(ImportDecl, ImportFunctionTemplateDecl) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template <typename T> void declToImport() { };",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionTemplateDecl());
}

TEST_P(ImportExpr, ImportCXXDependentScopeMemberExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template <typename T> struct C { T t; };"
      "template <typename T> void declToImport() {"
      "  C<T> d;"
      "  (void)d.t;"
      "}"
      "void instantiate() { declToImport<int>(); }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionTemplateDecl(hasDescendant(
          cStyleCastExpr(has(cxxDependentScopeMemberExpr())))));
  testImport(
      "template <typename T> struct C { T t; };"
      "template <typename T> void declToImport() {"
      "  C<T> d;"
      "  (void)(&d)->t;"
      "}"
      "void instantiate() { declToImport<int>(); }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionTemplateDecl(hasDescendant(
          cStyleCastExpr(has(cxxDependentScopeMemberExpr())))));
}

TEST_P(ImportType, ImportTypeAliasTemplate) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template <int K>"
      "struct dummy { static const int i = K; };"
      "template <int K> using dummy2 = dummy<K>;"
      "int declToImport() { return dummy2<3>::i; }",
      Lang_CXX11, "", Lang_CXX11, Verifier,
      functionDecl(
          hasDescendant(implicitCastExpr(has(declRefExpr()))),
          unless(hasAncestor(translationUnitDecl(has(typeAliasDecl()))))));
}

const internal::VariadicDynCastAllOfMatcher<Decl, VarTemplateSpecializationDecl>
    varTemplateSpecializationDecl;

TEST_P(ImportDecl, ImportVarTemplate) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template <typename T>"
      "T pi = T(3.1415926535897932385L);"
      "void declToImport() { (void)pi<int>; }",
      Lang_CXX14, "", Lang_CXX14, Verifier,
      functionDecl(
          hasDescendant(declRefExpr(to(varTemplateSpecializationDecl()))),
          unless(hasAncestor(translationUnitDecl(has(varDecl(
              hasName("pi"), unless(varTemplateSpecializationDecl()))))))));
}

TEST_P(ImportType, ImportPackExpansion) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template <typename... Args>"
      "struct dummy {"
      "  dummy(Args... args) {}"
      "  static const int i = 4;"
      "};"
      "int declToImport() { return dummy<int>::i; }",
      Lang_CXX11, "", Lang_CXX11, Verifier,
      functionDecl(hasDescendant(
          returnStmt(has(implicitCastExpr(has(declRefExpr())))))));
}

const internal::VariadicDynCastAllOfMatcher<Type,
                                            DependentTemplateSpecializationType>
    dependentTemplateSpecializationType;

TEST_P(ImportType, ImportDependentTemplateSpecialization) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template<typename T>"
      "struct A;"
      "template<typename T>"
      "struct declToImport {"
      "  typename A<T>::template B<T> a;"
      "};",
      Lang_CXX, "", Lang_CXX, Verifier,
      classTemplateDecl(has(cxxRecordDecl(has(
          fieldDecl(hasType(dependentTemplateSpecializationType())))))));
}

const internal::VariadicDynCastAllOfMatcher<Stmt, SizeOfPackExpr>
    sizeOfPackExpr;

TEST_P(ImportExpr, ImportSizeOfPackExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template <typename... Ts>"
      "void declToImport() {"
      "  const int i = sizeof...(Ts);"
      "};"
      "void g() { declToImport<int>(); }",
      Lang_CXX11, "", Lang_CXX11, Verifier,
          functionTemplateDecl(hasDescendant(sizeOfPackExpr())));
  testImport(
      "template <typename... Ts>"
      "using X = int[sizeof...(Ts)];"
      "template <typename... Us>"
      "struct Y {"
      "  X<Us..., int, double, int, Us...> f;"
      "};"
      "Y<float, int> declToImport;",
      Lang_CXX11, "", Lang_CXX11, Verifier,
      varDecl(hasType(classTemplateSpecializationDecl(has(fieldDecl(hasType(
          hasUnqualifiedDesugaredType(constantArrayType(hasSize(7))))))))));
}

/// \brief Matches __builtin_types_compatible_p:
/// GNU extension to check equivalent types
/// Given
/// \code
///   __builtin_types_compatible_p(int, int)
/// \endcode
//  will generate TypeTraitExpr <...> 'int'
const internal::VariadicDynCastAllOfMatcher<Stmt, TypeTraitExpr> typeTraitExpr;

TEST_P(ImportExpr, ImportTypeTraitExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "void declToImport() { "
      "  (void)__builtin_types_compatible_p(int, int);"
      "}",
      Lang_C, "", Lang_C, Verifier,
      functionDecl(hasDescendant(typeTraitExpr(hasType(asString("int"))))));
}

const internal::VariadicDynCastAllOfMatcher<Stmt, CXXTypeidExpr> cxxTypeidExpr;

TEST_P(ImportExpr, ImportCXXTypeidExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "namespace std { class type_info {}; }"
      "void declToImport() {"
      "  int x;"
      "  auto a = typeid(int); auto b = typeid(x);"
      "}",
      Lang_CXX11, "", Lang_CXX11, Verifier,
      functionDecl(
          hasDescendant(varDecl(
              hasName("a"), hasInitializer(hasDescendant(cxxTypeidExpr())))),
          hasDescendant(varDecl(
              hasName("b"), hasInitializer(hasDescendant(cxxTypeidExpr()))))));
}

TEST_P(ImportExpr, ImportTypeTraitExprValDep) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template<typename T> struct declToImport {"
      "  void m() { (void)__is_pod(T); }"
      "};"
      "void f() { declToImport<int>().m(); }",
      Lang_CXX11, "", Lang_CXX11, Verifier,
      classTemplateDecl(has(cxxRecordDecl(has(
          functionDecl(hasDescendant(
              typeTraitExpr(hasType(booleanType())))))))));
}

TEST_P(ImportDecl, ImportRecordDeclInFunc) {
  MatchVerifier<Decl> Verifier;
  testImport("int declToImport() { "
             "  struct data_t {int a;int b;};"
             "  struct data_t d;"
             "  return 0;"
             "}",
             Lang_C, "", Lang_C, Verifier,
             functionDecl(hasBody(compoundStmt(
                 has(declStmt(hasSingleDecl(varDecl(hasName("d")))))))));
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportRecordTypeInFunc) {
  Decl *FromTU = getTuDecl("int declToImport() { "
                           "  struct data_t {int a;int b;};"
                           "  struct data_t d;"
                           "  return 0;"
                           "}",
                           Lang_C, "input.c");
  auto *FromVar =
      FirstDeclMatcher<VarDecl>().match(FromTU, varDecl(hasName("d")));
  ASSERT_TRUE(FromVar);
  auto ToType =
      ImportType(FromVar->getType().getCanonicalType(), FromVar, Lang_C);
  EXPECT_FALSE(ToType.isNull());
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportRecordDeclInFuncParams) {
  // This construct is not supported by ASTImporter.
  Decl *FromTU = getTuDecl(
      "int declToImport(struct data_t{int a;int b;} ***d){ return 0; }",
      Lang_C, "input.c");
  auto *From = FirstDeclMatcher<FunctionDecl>().match(
      FromTU, functionDecl(hasName("declToImport")));
  ASSERT_TRUE(From);
  auto *To = Import(From, Lang_C);
  EXPECT_EQ(To, nullptr);
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportRecordDeclInFuncFromMacro) {
  Decl *FromTU = getTuDecl(
      "#define NONAME_SIZEOF(type) sizeof(struct{type *dummy;}) \n"
      "int declToImport(){ return NONAME_SIZEOF(int); }",
      Lang_C, "input.c");
  auto *From = FirstDeclMatcher<FunctionDecl>().match(
      FromTU, functionDecl(hasName("declToImport")));
  ASSERT_TRUE(From);
  auto *To = Import(From, Lang_C);
  ASSERT_TRUE(To);
  EXPECT_TRUE(MatchVerifier<FunctionDecl>().match(
      To, functionDecl(hasName("declToImport"),
                       hasDescendant(unaryExprOrTypeTraitExpr()))));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       ImportRecordDeclInFuncParamsFromMacro) {
  // This construct is not supported by ASTImporter.
  Decl *FromTU = getTuDecl(
      "#define PAIR_STRUCT(type) struct data_t{type a;type b;} \n"
      "int declToImport(PAIR_STRUCT(int) ***d){ return 0; }",
      Lang_C, "input.c");
  auto *From = FirstDeclMatcher<FunctionDecl>().match(
      FromTU, functionDecl(hasName("declToImport")));
  ASSERT_TRUE(From);
  auto *To = Import(From, Lang_C);
  EXPECT_EQ(To, nullptr);
}

const internal::VariadicDynCastAllOfMatcher<Expr, CXXPseudoDestructorExpr>
    cxxPseudoDestructorExpr;

TEST_P(ImportExpr, ImportCXXPseudoDestructorExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "typedef int T;"
      "void declToImport(int *p) {"
      "  T t;"
      "  p->T::~T();"
      "}",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(
          callExpr(has(cxxPseudoDestructorExpr())))));
}

TEST_P(ImportDecl, ImportUsingDecl) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "namespace foo { int bar; }"
      "void declToImport() { using foo::bar; }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionDecl(hasDescendant(usingDecl())));
}

/// \brief Matches shadow declarations introduced into a scope by a
///        (resolved) using declaration.
///
/// Given
/// \code
///   namespace n { int f; }
///   namespace declToImport { using n::f; }
/// \endcode
/// usingShadowDecl()
///   matches \code f \endcode
const internal::VariadicDynCastAllOfMatcher<Decl,
                                            UsingShadowDecl> usingShadowDecl;

TEST_P(ImportDecl, ImportUsingShadowDecl) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "namespace foo { int bar; }"
      "namespace declToImport { using foo::bar; }",
      Lang_CXX, "", Lang_CXX, Verifier,
      namespaceDecl(has(usingShadowDecl())));
}

TEST_P(ImportExpr, ImportUnresolvedLookupExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template<typename T> int foo();"
      "template <typename T> void declToImport() {"
      "  (void)::foo<T>;"
      "  (void)::template foo<T>;"
      "}"
      "void instantiate() { declToImport<int>(); }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionTemplateDecl(hasDescendant(unresolvedLookupExpr())));
}

TEST_P(ImportExpr, ImportCXXUnresolvedConstructExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template <typename T> struct C { T t; };"
      "template <typename T> void declToImport() {"
      "  C<T> d;"
      "  d.t = T();"
      "}"
      "void instantiate() { declToImport<int>(); }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionTemplateDecl(hasDescendant(
          binaryOperator(has(cxxUnresolvedConstructExpr())))));
  testImport(
      "template <typename T> struct C { T t; };"
      "template <typename T> void declToImport() {"
      "  C<T> d;"
      "  (&d)->t = T();"
      "}"
      "void instantiate() { declToImport<int>(); }",
      Lang_CXX, "", Lang_CXX, Verifier,
          functionTemplateDecl(hasDescendant(
              binaryOperator(has(cxxUnresolvedConstructExpr())))));
}

/// Check that function "declToImport()" (which is the templated function
/// for corresponding FunctionTemplateDecl) is not added into DeclContext.
/// Same for class template declarations.
TEST_P(ImportDecl, ImportTemplatedDeclForTemplate) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template <typename T> void declToImport() { T a = 1; }"
      "void instantiate() { declToImport<int>(); }",
      Lang_CXX, "", Lang_CXX, Verifier,
      functionTemplateDecl(hasAncestor(translationUnitDecl(
          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_P(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_P(ImportExpr, CXXOperatorCallExpr) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "class declToImport {"
      "  void f() { *this = declToImport(); }"
      "};",
      Lang_CXX, "", Lang_CXX, Verifier,
      cxxRecordDecl(has(cxxMethodDecl(hasDescendant(
          cxxOperatorCallExpr())))));
}

TEST_P(ImportExpr, DependentSizedArrayType) {
  MatchVerifier<Decl> Verifier;
  testImport(
      "template<typename T, int Size> class declToImport {"
      "  T data[Size];"
      "};",
      Lang_CXX, "", Lang_CXX, Verifier,
      classTemplateDecl(has(cxxRecordDecl(
          has(fieldDecl(hasType(dependentSizedArrayType())))))));
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportBeginLocOfDeclRefExpr) {
  Decl *FromTU = getTuDecl(
      "class A { public: static int X; }; void f() { (void)A::X; }", Lang_CXX);
  auto From = FirstDeclMatcher<FunctionDecl>().match(
      FromTU, functionDecl(hasName("f")));
  ASSERT_TRUE(From);
  ASSERT_TRUE(
      cast<CStyleCastExpr>(cast<CompoundStmt>(From->getBody())->body_front())
          ->getSubExpr()
          ->getBeginLoc()
          .isValid());
  FunctionDecl *To = Import(From, Lang_CXX);
  ASSERT_TRUE(To);
  ASSERT_TRUE(
      cast<CStyleCastExpr>(cast<CompoundStmt>(To->getBody())->body_front())
          ->getSubExpr()
          ->getBeginLoc()
          .isValid());
}

TEST_P(ASTImporterOptionSpecificTestBase,
       ImportOfTemplatedDeclOfClassTemplateDecl) {
  Decl *FromTU = getTuDecl("template<class X> struct S{};", Lang_CXX);
  auto From =
      FirstDeclMatcher<ClassTemplateDecl>().match(FromTU, classTemplateDecl());
  ASSERT_TRUE(From);
  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(ASTImporterOptionSpecificTestBase,
       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(ASTImporterOptionSpecificTestBase,
       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(ASTImporterOptionSpecificTestBase,
       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(ASTImporterOptionSpecificTestBase, ImportCorrectTemplatedDecl) {
  auto Code =
        R"(
        namespace x {
          template<class X> struct S1{};
          template<class X> struct S2{};
          template<class X> struct S3{};
        }
        )";
  Decl *FromTU = getTuDecl(Code, Lang_CXX);
  auto FromNs =
      FirstDeclMatcher<NamespaceDecl>().match(FromTU, namespaceDecl());
  auto ToNs = cast<NamespaceDecl>(Import(FromNs, Lang_CXX));
  ASSERT_TRUE(ToNs);
  auto From =
      FirstDeclMatcher<ClassTemplateDecl>().match(FromTU,
                                                  classTemplateDecl(
                                                      hasName("S2")));
  auto To =
      FirstDeclMatcher<ClassTemplateDecl>().match(ToNs,
                                                  classTemplateDecl(
                                                      hasName("S2")));
  ASSERT_TRUE(From);
  ASSERT_TRUE(To);
  auto ToTemplated = To->getTemplatedDecl();
  auto ToTemplated1 =
      cast<CXXRecordDecl>(Import(From->getTemplatedDecl(), Lang_CXX));
  EXPECT_TRUE(ToTemplated1);
  ASSERT_EQ(ToTemplated1, ToTemplated);
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportChooseExpr) {
  // This tests the import of isConditionTrue directly to make sure the importer
  // gets it right.
  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
    "void declToImport() { (void)__builtin_choose_expr(1, 0, 1); }",
    Lang_C, "", Lang_C);

  auto ToResults = match(chooseExpr().bind("choose"), To->getASTContext());
  auto FromResults = match(chooseExpr().bind("choose"), From->getASTContext());

  const ChooseExpr *FromChooseExpr =
      selectFirst<ChooseExpr>("choose", FromResults);
  ASSERT_TRUE(FromChooseExpr);

  const ChooseExpr *ToChooseExpr = selectFirst<ChooseExpr>("choose", ToResults);
  ASSERT_TRUE(ToChooseExpr);

  EXPECT_EQ(FromChooseExpr->isConditionTrue(), ToChooseExpr->isConditionTrue());
  EXPECT_EQ(FromChooseExpr->isConditionDependent(),
            ToChooseExpr->isConditionDependent());
}

TEST_P(ASTImporterOptionSpecificTestBase,
       ImportFunctionWithBackReferringParameter) {
  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
      R"(
      template <typename T> struct X {};

      void declToImport(int y, X<int> &x) {}

      template <> struct X<int> {
        void g() {
          X<int> x;
          declToImport(0, x);
        }
      };
      )",
      Lang_CXX, "", Lang_CXX);

  MatchVerifier<Decl> Verifier;
  auto Matcher = functionDecl(hasName("declToImport"),
                              parameterCountIs(2),
                              hasParameter(0, hasName("y")),
                              hasParameter(1, hasName("x")),
                              hasParameter(1, hasType(asString("X<int> &"))));
  ASSERT_TRUE(Verifier.match(From, Matcher));
  EXPECT_TRUE(Verifier.match(To, Matcher));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       TUshouldNotContainTemplatedDeclOfFunctionTemplates) {
  Decl *From, *To;
  std::tie(From, To) =
      getImportedDecl("template <typename T> void declToImport() { T a = 1; }"
                      "void instantiate() { declToImport<int>(); }",
                      Lang_CXX, "", Lang_CXX);

  auto Check = [](Decl *D) -> bool {
    auto TU = D->getTranslationUnitDecl();
    for (auto Child : TU->decls()) {
      if (auto *FD = dyn_cast<FunctionDecl>(Child)) {
        if (FD->getNameAsString() == "declToImport") {
          GTEST_NONFATAL_FAILURE_(
              "TU should not contain any FunctionDecl with name declToImport");
          return false;
        }
      }
    }
    return true;
  };

  ASSERT_TRUE(Check(From));
  EXPECT_TRUE(Check(To));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       TUshouldNotContainTemplatedDeclOfClassTemplates) {
  Decl *From, *To;
  std::tie(From, To) =
      getImportedDecl("template <typename T> struct declToImport { T t; };"
                      "void instantiate() { declToImport<int>(); }",
                      Lang_CXX, "", Lang_CXX);

  auto Check = [](Decl *D) -> bool {
    auto TU = D->getTranslationUnitDecl();
    for (auto Child : TU->decls()) {
      if (auto *RD = dyn_cast<CXXRecordDecl>(Child)) {
        if (RD->getNameAsString() == "declToImport") {
          GTEST_NONFATAL_FAILURE_(
              "TU should not contain any CXXRecordDecl with name declToImport");
          return false;
        }
      }
    }
    return true;
  };

  ASSERT_TRUE(Check(From));
  EXPECT_TRUE(Check(To));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       TUshouldNotContainTemplatedDeclOfTypeAlias) {
  Decl *From, *To;
  std::tie(From, To) =
      getImportedDecl(
          "template <typename T> struct X {};"
          "template <typename T> using declToImport = X<T>;"
          "void instantiate() { declToImport<int> a; }",
                      Lang_CXX11, "", Lang_CXX11);

  auto Check = [](Decl *D) -> bool {
    auto TU = D->getTranslationUnitDecl();
    for (auto Child : TU->decls()) {
      if (auto *AD = dyn_cast<TypeAliasDecl>(Child)) {
        if (AD->getNameAsString() == "declToImport") {
          GTEST_NONFATAL_FAILURE_(
              "TU should not contain any TypeAliasDecl with name declToImport");
          return false;
        }
      }
    }
    return true;
  };

  ASSERT_TRUE(Check(From));
  EXPECT_TRUE(Check(To));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       TUshouldNotContainClassTemplateSpecializationOfImplicitInstantiation) {

  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
      R"(
      template<class T>
      class Base {};
      class declToImport : public Base<declToImport> {};
      )",
      Lang_CXX, "", Lang_CXX);

  // Check that the ClassTemplateSpecializationDecl is NOT the child of the TU.
  auto Pattern =
      translationUnitDecl(unless(has(classTemplateSpecializationDecl())));
  ASSERT_TRUE(
      MatchVerifier<Decl>{}.match(From->getTranslationUnitDecl(), Pattern));
  EXPECT_TRUE(
      MatchVerifier<Decl>{}.match(To->getTranslationUnitDecl(), Pattern));

  // Check that the ClassTemplateSpecializationDecl is the child of the
  // ClassTemplateDecl.
  Pattern = translationUnitDecl(has(classTemplateDecl(
      hasName("Base"), has(classTemplateSpecializationDecl()))));
  ASSERT_TRUE(
      MatchVerifier<Decl>{}.match(From->getTranslationUnitDecl(), Pattern));
  EXPECT_TRUE(
      MatchVerifier<Decl>{}.match(To->getTranslationUnitDecl(), Pattern));
}

AST_MATCHER_P(RecordDecl, hasFieldOrder, std::vector<StringRef>, Order) {
  size_t Index = 0;
  for (Decl *D : Node.decls()) {
    if (isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) {
      auto *ND = cast<NamedDecl>(D);
      if (Index == Order.size())
        return false;
      if (ND->getName() != Order[Index])
        return false;
      ++Index;
    }
  }
  return Index == Order.size();
}

TEST_P(ASTImporterOptionSpecificTestBase,
       TUshouldContainClassTemplateSpecializationOfExplicitInstantiation) {
  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
      R"(
      namespace NS {
        template<class T>
        class X {};
        template class X<int>;
      }
      )",
      Lang_CXX, "", Lang_CXX, "NS");

  // Check that the ClassTemplateSpecializationDecl is NOT the child of the
  // ClassTemplateDecl.
  auto Pattern = namespaceDecl(has(classTemplateDecl(
      hasName("X"), unless(has(classTemplateSpecializationDecl())))));
  ASSERT_TRUE(MatchVerifier<Decl>{}.match(From, Pattern));
  EXPECT_TRUE(MatchVerifier<Decl>{}.match(To, Pattern));

  // Check that the ClassTemplateSpecializationDecl is the child of the
  // NamespaceDecl.
  Pattern = namespaceDecl(has(classTemplateSpecializationDecl(hasName("X"))));
  ASSERT_TRUE(MatchVerifier<Decl>{}.match(From, Pattern));
  EXPECT_TRUE(MatchVerifier<Decl>{}.match(To, Pattern));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       CXXRecordDeclFieldsShouldBeInCorrectOrder) {
  Decl *From, *To;
  std::tie(From, To) =
      getImportedDecl(
          "struct declToImport { int a; int b; };",
                      Lang_CXX11, "", Lang_CXX11);

  MatchVerifier<Decl> Verifier;
  ASSERT_TRUE(Verifier.match(From, cxxRecordDecl(hasFieldOrder({"a", "b"}))));
  EXPECT_TRUE(Verifier.match(To, cxxRecordDecl(hasFieldOrder({"a", "b"}))));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       CXXRecordDeclFieldOrderShouldNotDependOnImportOrder) {
  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
      // The original recursive algorithm of ASTImporter first imports 'c' then
      // 'b' and lastly 'a'.  Therefore we must restore the order somehow.
      R"s(
      struct declToImport {
          int a = c + b;
          int b = 1;
          int c = 2;
      };
      )s",
      Lang_CXX11, "", Lang_CXX11);

  MatchVerifier<Decl> Verifier;
  ASSERT_TRUE(
      Verifier.match(From, cxxRecordDecl(hasFieldOrder({"a", "b", "c"}))));
  EXPECT_TRUE(
      Verifier.match(To, cxxRecordDecl(hasFieldOrder({"a", "b", "c"}))));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       CXXRecordDeclFieldAndIndirectFieldOrder) {
  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
      // First field is "a", then the field for unnamed union, then "b" and "c"
      // from it (indirect fields), then "d".
      R"s(
      struct declToImport {
        int a = d;
        union { 
          int b;
          int c;
        };
        int d;
      };
      )s",
      Lang_CXX11, "", Lang_CXX11);

  MatchVerifier<Decl> Verifier;
  ASSERT_TRUE(Verifier.match(
      From, cxxRecordDecl(hasFieldOrder({"a", "", "b", "c", "d"}))));
  EXPECT_TRUE(Verifier.match(
      To, cxxRecordDecl(hasFieldOrder({"a", "", "b", "c", "d"}))));
}

TEST_P(ASTImporterOptionSpecificTestBase, ShouldImportImplicitCXXRecordDecl) {
  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
      R"(
      struct declToImport {
      };
      )",
      Lang_CXX, "", Lang_CXX);

  MatchVerifier<Decl> Verifier;
  // Match the implicit Decl.
  auto Matcher = cxxRecordDecl(has(cxxRecordDecl()));
  ASSERT_TRUE(Verifier.match(From, Matcher));
  EXPECT_TRUE(Verifier.match(To, Matcher));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       ShouldImportImplicitCXXRecordDeclOfClassTemplate) {
  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
      R"(
      template <typename U>
      struct declToImport {
      };
      )",
      Lang_CXX, "", Lang_CXX);

  MatchVerifier<Decl> Verifier;
  // Match the implicit Decl.
  auto Matcher = classTemplateDecl(has(cxxRecordDecl(has(cxxRecordDecl()))));
  ASSERT_TRUE(Verifier.match(From, Matcher));
  EXPECT_TRUE(Verifier.match(To, Matcher));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       ShouldImportImplicitCXXRecordDeclOfClassTemplateSpecializationDecl) {
  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
      R"(
      template<class T>
      class Base {};
      class declToImport : public Base<declToImport> {};
      )",
      Lang_CXX, "", Lang_CXX);

  auto hasImplicitClass = has(cxxRecordDecl());
  auto Pattern = translationUnitDecl(has(classTemplateDecl(
      hasName("Base"),
      has(classTemplateSpecializationDecl(hasImplicitClass)))));
  ASSERT_TRUE(
      MatchVerifier<Decl>{}.match(From->getTranslationUnitDecl(), Pattern));
  EXPECT_TRUE(
      MatchVerifier<Decl>{}.match(To->getTranslationUnitDecl(), Pattern));
}

TEST_P(ASTImporterOptionSpecificTestBase, IDNSOrdinary) {
  Decl *From, *To;
  std::tie(From, To) =
      getImportedDecl("void declToImport() {}", Lang_CXX, "", Lang_CXX);

  MatchVerifier<Decl> Verifier;
  auto Matcher = functionDecl();
  ASSERT_TRUE(Verifier.match(From, Matcher));
  EXPECT_TRUE(Verifier.match(To, Matcher));
  EXPECT_EQ(From->getIdentifierNamespace(), To->getIdentifierNamespace());
}

TEST_P(ASTImporterOptionSpecificTestBase, IDNSOfNonmemberOperator) {
  Decl *FromTU = getTuDecl(
      R"(
      struct X {};
      void operator<<(int, X);
      )",
      Lang_CXX);
  Decl *From = LastDeclMatcher<Decl>{}.match(FromTU, functionDecl());
  const Decl *To = Import(From, Lang_CXX);
  EXPECT_EQ(From->getIdentifierNamespace(), To->getIdentifierNamespace());
}

TEST_P(ASTImporterOptionSpecificTestBase,
       ShouldImportMembersOfClassTemplateSpecializationDecl) {
  Decl *From, *To;
  std::tie(From, To) = getImportedDecl(
      R"(
      template<class T>
      class Base { int a; };
      class declToImport : Base<declToImport> {};
      )",
      Lang_CXX, "", Lang_CXX);

  auto Pattern = translationUnitDecl(has(classTemplateDecl(
      hasName("Base"),
      has(classTemplateSpecializationDecl(has(fieldDecl(hasName("a"))))))));
  ASSERT_TRUE(
      MatchVerifier<Decl>{}.match(From->getTranslationUnitDecl(), Pattern));
  EXPECT_TRUE(
      MatchVerifier<Decl>{}.match(To->getTranslationUnitDecl(), Pattern));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       ImportDefinitionOfClassTemplateAfterFwdDecl) {
  {
    Decl *FromTU = getTuDecl(
        R"(
            template <typename T>
            struct B;
            )",
        Lang_CXX, "input0.cc");
    auto *FromD = FirstDeclMatcher<ClassTemplateDecl>().match(
        FromTU, classTemplateDecl(hasName("B")));

    Import(FromD, Lang_CXX);
  }

  {
    Decl *FromTU = getTuDecl(
        R"(
            template <typename T>
            struct B {
              void f();
            };
            )",
        Lang_CXX, "input1.cc");
    FunctionDecl *FromD = FirstDeclMatcher<FunctionDecl>().match(
        FromTU, functionDecl(hasName("f")));
    Import(FromD, Lang_CXX);
    auto *FromCTD = FirstDeclMatcher<ClassTemplateDecl>().match(
        FromTU, classTemplateDecl(hasName("B")));
    auto *ToCTD = cast<ClassTemplateDecl>(Import(FromCTD, Lang_CXX));
    EXPECT_TRUE(ToCTD->isThisDeclarationADefinition());
  }
}

TEST_P(ASTImporterOptionSpecificTestBase,
       ImportDefinitionOfClassTemplateIfThereIsAnExistingFwdDeclAndDefinition) {
  Decl *ToTU = getToTuDecl(
      R"(
      template <typename T>
      struct B {
        void f();
      };

      template <typename T>
      struct B;
      )",
      Lang_CXX);
  ASSERT_EQ(1u, DeclCounterWithPredicate<ClassTemplateDecl>(
                    [](const ClassTemplateDecl *T) {
                      return T->isThisDeclarationADefinition();
                    })
                    .match(ToTU, classTemplateDecl()));

  Decl *FromTU = getTuDecl(
      R"(
      template <typename T>
      struct B {
        void f();
      };
      )",
      Lang_CXX, "input1.cc");
  ClassTemplateDecl *FromD = FirstDeclMatcher<ClassTemplateDecl>().match(
      FromTU, classTemplateDecl(hasName("B")));

  Import(FromD, Lang_CXX);

  // We should have only one definition.
  EXPECT_EQ(1u, DeclCounterWithPredicate<ClassTemplateDecl>(
                    [](const ClassTemplateDecl *T) {
                      return T->isThisDeclarationADefinition();
                    })
                    .match(ToTU, classTemplateDecl()));
}

TEST_P(ASTImporterOptionSpecificTestBase,
       ImportDefinitionOfClassIfThereIsAnExistingFwdDeclAndDefinition) {
  Decl *ToTU = getToTuDecl(
      R"(
      struct B {
        void f();
      };

      struct B;
      )",
      Lang_CXX);
  ASSERT_EQ(2u, DeclCounter<CXXRecordDecl>().match(
                    ToTU, cxxRecordDecl(unless(isImplicit()))));

  Decl *FromTU = getTuDecl(
      R"(
      struct B {
        void f();
      };
      )",
      Lang_CXX, "input1.cc");
  auto *FromD = FirstDeclMatcher<CXXRecordDecl>().match(
      FromTU, cxxRecordDecl(hasName("B")));

  Import(FromD, Lang_CXX);

  EXPECT_EQ(2u, DeclCounter<CXXRecordDecl>().match(
                    ToTU, cxxRecordDecl(unless(isImplicit()))));
}

static void CompareSourceLocs(FullSourceLoc Loc1, FullSourceLoc Loc2) {
  EXPECT_EQ(Loc1.getExpansionLineNumber(), Loc2.getExpansionLineNumber());
  EXPECT_EQ(Loc1.getExpansionColumnNumber(), Loc2.getExpansionColumnNumber());
  EXPECT_EQ(Loc1.getSpellingLineNumber(), Loc2.getSpellingLineNumber());
  EXPECT_EQ(Loc1.getSpellingColumnNumber(), Loc2.getSpellingColumnNumber());
}
static void CompareSourceRanges(SourceRange Range1, SourceRange Range2,
                                SourceManager &SM1, SourceManager &SM2) {
  CompareSourceLocs(FullSourceLoc{ Range1.getBegin(), SM1 },
                    FullSourceLoc{ Range2.getBegin(), SM2 });
  CompareSourceLocs(FullSourceLoc{ Range1.getEnd(), SM1 },
                    FullSourceLoc{ Range2.getEnd(), SM2 });
}
TEST_P(ASTImporterOptionSpecificTestBase, ImportSourceLocs) {
  Decl *FromTU = getTuDecl(
      R"(
      #define MFOO(arg) arg = arg + 1

      void foo() {
        int a = 5;
        MFOO(a);
      }
      )",
      Lang_CXX);
  auto FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());
  auto ToD = Import(FromD, Lang_CXX);

  auto ToLHS = LastDeclMatcher<DeclRefExpr>().match(ToD, declRefExpr());
  auto FromLHS = LastDeclMatcher<DeclRefExpr>().match(FromTU, declRefExpr());
  auto ToRHS = LastDeclMatcher<IntegerLiteral>().match(ToD, integerLiteral());
  auto FromRHS =
      LastDeclMatcher<IntegerLiteral>().match(FromTU, integerLiteral());

  SourceManager &ToSM = ToAST->getASTContext().getSourceManager();
  SourceManager &FromSM = FromD->getASTContext().getSourceManager();
  CompareSourceRanges(ToD->getSourceRange(), FromD->getSourceRange(), ToSM,
                      FromSM);
  CompareSourceRanges(ToLHS->getSourceRange(), FromLHS->getSourceRange(), ToSM,
                      FromSM);
  CompareSourceRanges(ToRHS->getSourceRange(), FromRHS->getSourceRange(), ToSM,
                      FromSM);
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportNestedMacro) {
  Decl *FromTU = getTuDecl(
      R"(
      #define FUNC_INT void declToImport
      #define FUNC FUNC_INT
      FUNC(int a);
      )",
      Lang_CXX);
  auto FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());
  auto ToD = Import(FromD, Lang_CXX);

  SourceManager &ToSM = ToAST->getASTContext().getSourceManager();
  SourceManager &FromSM = FromD->getASTContext().getSourceManager();
  CompareSourceRanges(ToD->getSourceRange(), FromD->getSourceRange(), ToSM,
                      FromSM);
}

TEST_P(
    ASTImporterOptionSpecificTestBase,
    ImportDefinitionOfClassTemplateSpecIfThereIsAnExistingFwdDeclAndDefinition) {
  Decl *ToTU = getToTuDecl(
      R"(
      template <typename T>
      struct B;

      template <>
      struct B<int> {};

      template <>
      struct B<int>;
      )",
      Lang_CXX);
  // We should have only one definition.
  ASSERT_EQ(1u, DeclCounterWithPredicate<ClassTemplateSpecializationDecl>(
                    [](const ClassTemplateSpecializationDecl *T) {
                      return T->isThisDeclarationADefinition();
                    })
                    .match(ToTU, classTemplateSpecializationDecl()));

  Decl *FromTU = getTuDecl(
      R"(
      template <typename T>
      struct B;

      template <>
      struct B<int> {};
      )",
      Lang_CXX, "input1.cc");
  auto *FromD = FirstDeclMatcher<ClassTemplateSpecializationDecl>().match(
      FromTU, classTemplateSpecializationDecl(hasName("B")));

  Import(FromD, Lang_CXX);

  // We should have only one definition.
  EXPECT_EQ(1u, DeclCounterWithPredicate<ClassTemplateSpecializationDecl>(
                    [](const ClassTemplateSpecializationDecl *T) {
                      return T->isThisDeclarationADefinition();
                    })
                    .match(ToTU, classTemplateSpecializationDecl()));
}

TEST_P(ASTImporterOptionSpecificTestBase, ObjectsWithUnnamedStructType) {
  Decl *FromTU = getTuDecl(
      R"(
      struct { int a; int b; } object0 = { 2, 3 };
      struct { int x; int y; int z; } object1;
      )",
      Lang_CXX, "input0.cc");

  auto *Obj0 =
      FirstDeclMatcher<VarDecl>().match(FromTU, varDecl(hasName("object0")));
  auto *From0 = getRecordDecl(Obj0);
  auto *Obj1 =
      FirstDeclMatcher<VarDecl>().match(FromTU, varDecl(hasName("object1")));
  auto *From1 = getRecordDecl(Obj1);

  auto *To0 = Import(From0, Lang_CXX);
  auto *To1 = Import(From1, Lang_CXX);

  EXPECT_TRUE(To0);
  EXPECT_TRUE(To1);
  EXPECT_NE(To0, To1);
  EXPECT_NE(To0->getCanonicalDecl(), To1->getCanonicalDecl());
}

TEST_P(ASTImporterOptionSpecificTestBase, AnonymousRecords) {
  auto *Code =
      R"(
      struct X {
        struct { int a; };
        struct { int b; };
      };
      )";
  Decl *FromTU0 = getTuDecl(Code, Lang_C, "input0.c");

  Decl *FromTU1 = getTuDecl(Code, Lang_C, "input1.c");

  auto *X0 =
      FirstDeclMatcher<RecordDecl>().match(FromTU0, recordDecl(hasName("X")));
  auto *X1 =
      FirstDeclMatcher<RecordDecl>().match(FromTU1, recordDecl(hasName("X")));
  Import(X0, Lang_C);
  Import(X1, Lang_C);

  auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  // We expect no (ODR) warning during the import.
  EXPECT_EQ(0u, ToTU->getASTContext().getDiagnostics().getNumWarnings());
  EXPECT_EQ(1u,
            DeclCounter<RecordDecl>().match(ToTU, recordDecl(hasName("X"))));
}

TEST_P(ASTImporterOptionSpecificTestBase, AnonymousRecordsReversed) {
  Decl *FromTU0 = getTuDecl(
      R"(
      struct X {
        struct { int a; };
        struct { int b; };
      };
      )",
      Lang_C, "input0.c");

  Decl *FromTU1 = getTuDecl(
      R"(
      struct X { // reversed order
        struct { int b; };
        struct { int a; };
      };
      )",
      Lang_C, "input1.c");

  auto *X0 =
      FirstDeclMatcher<RecordDecl>().match(FromTU0, recordDecl(hasName("X")));
  auto *X1 =
      FirstDeclMatcher<RecordDecl>().match(FromTU1, recordDecl(hasName("X")));
  Import(X0, Lang_C);
  Import(X1, Lang_C);

  auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  // We expect one (ODR) warning during the import.
  EXPECT_EQ(1u, ToTU->getASTContext().getDiagnostics().getNumWarnings());
  EXPECT_EQ(1u,
            DeclCounter<RecordDecl>().match(ToTU, recordDecl(hasName("X"))));
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportDoesUpdateUsedFlag) {
  auto Pattern = varDecl(hasName("x"));
  VarDecl *Imported1;
  {
    Decl *FromTU = getTuDecl("extern int x;", Lang_CXX, "input0.cc");
    auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
    Imported1 = cast<VarDecl>(Import(FromD, Lang_CXX));
  }
  VarDecl *Imported2;
  {
    Decl *FromTU = getTuDecl("int x;", Lang_CXX, "input1.cc");
    auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
    Imported2 = cast<VarDecl>(Import(FromD, Lang_CXX));
  }
  EXPECT_EQ(Imported1->getCanonicalDecl(), Imported2->getCanonicalDecl());
  EXPECT_FALSE(Imported2->isUsed(false));
  {
    Decl *FromTU =
        getTuDecl("extern int x; int f() { return x; }", Lang_CXX, "input2.cc");
    auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
        FromTU, functionDecl(hasName("f")));
    Import(FromD, Lang_CXX);
  }
  EXPECT_TRUE(Imported2->isUsed(false));
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportDoesUpdateUsedFlag2) {
  auto Pattern = varDecl(hasName("x"));
  VarDecl *ExistingD;
  {
    Decl *ToTU = getToTuDecl("int x = 1;", Lang_CXX);
    ExistingD = FirstDeclMatcher<VarDecl>().match(ToTU, Pattern);
  }
  EXPECT_FALSE(ExistingD->isUsed(false));
  {
    Decl *FromTU = getTuDecl(
        "int x = 1; int f() { return x; }", Lang_CXX, "input1.cc");
    auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
        FromTU, functionDecl(hasName("f")));
    Import(FromD, Lang_CXX);
  }
  EXPECT_TRUE(ExistingD->isUsed(false));
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportDoesUpdateUsedFlag3) {
  auto Pattern = varDecl(hasName("a"));
  VarDecl *ExistingD;
  {
    Decl *ToTU = getToTuDecl(
        R"(
        struct A {
          static const int a = 1;
        };
        )", Lang_CXX);
    ExistingD = FirstDeclMatcher<VarDecl>().match(ToTU, Pattern);
  }
  EXPECT_FALSE(ExistingD->isUsed(false));
  {
    Decl *FromTU = getTuDecl(
        R"(
        struct A {
          static const int a = 1;
        };
        const int *f() { return &A::a; } // requires storage,
                                         // thus used flag will be set
        )", Lang_CXX, "input1.cc");
    auto *FromFunD = FirstDeclMatcher<FunctionDecl>().match(
        FromTU, functionDecl(hasName("f")));
    auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);
    ASSERT_TRUE(FromD->isUsed(false));
    Import(FromFunD, Lang_CXX);
  }
  EXPECT_TRUE(ExistingD->isUsed(false));
}

TEST_P(ASTImporterOptionSpecificTestBase, ReimportWithUsedFlag) {
  auto Pattern = varDecl(hasName("x"));

  Decl *FromTU = getTuDecl("int x;", Lang_CXX, "input0.cc");
  auto *FromD = FirstDeclMatcher<VarDecl>().match(FromTU, Pattern);

  auto *Imported1 = cast<VarDecl>(Import(FromD, Lang_CXX));

  ASSERT_FALSE(Imported1->isUsed(false));

  FromD->setIsUsed();
  auto *Imported2 = cast<VarDecl>(Import(FromD, Lang_CXX));

  EXPECT_EQ(Imported1, Imported2);
  EXPECT_TRUE(Imported2->isUsed(false));
}

struct ImportFunctions : ASTImporterOptionSpecificTestBase {};

TEST_P(ImportFunctions, ImportPrototypeOfRecursiveFunction) {
  Decl *FromTU = getTuDecl("void f(); void f() { f(); }", Lang_CXX);
  auto Pattern = functionDecl(hasName("f"));
  auto *From =
      FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern); // Proto

  Decl *ImportedD = Import(From, Lang_CXX);
  Decl *ToTU = ImportedD->getTranslationUnitDecl();

  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
  auto *To0 = FirstDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
  auto *To1 = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
  EXPECT_TRUE(ImportedD == To0);
  EXPECT_FALSE(To0->doesThisDeclarationHaveABody());
  EXPECT_TRUE(To1->doesThisDeclarationHaveABody());
  EXPECT_EQ(To1->getPreviousDecl(), To0);
}

TEST_P(ImportFunctions, ImportDefinitionOfRecursiveFunction) {
  Decl *FromTU = getTuDecl("void f(); void f() { f(); }", Lang_CXX);
  auto Pattern = functionDecl(hasName("f"));
  auto *From =
      LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern); // Def

  Decl *ImportedD = Import(From, Lang_CXX);
  Decl *ToTU = ImportedD->getTranslationUnitDecl();

  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
  auto *To0 = FirstDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
  auto *To1 = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
  EXPECT_TRUE(ImportedD == To1);
  EXPECT_FALSE(To0->doesThisDeclarationHaveABody());
  EXPECT_TRUE(To1->doesThisDeclarationHaveABody());
  EXPECT_EQ(To1->getPreviousDecl(), To0);
}

TEST_P(ImportFunctions, OverriddenMethodsShouldBeImported) {
  auto Code =
      R"(
      struct B { virtual void f(); };
      void B::f() {}
      struct D : B { void f(); };
      )";
  auto Pattern =
      cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))));
  Decl *FromTU = getTuDecl(Code, Lang_CXX);
  CXXMethodDecl *Proto =
      FirstDeclMatcher<CXXMethodDecl>().match(FromTU, Pattern);

  ASSERT_EQ(Proto->size_overridden_methods(), 1u);
  CXXMethodDecl *To = cast<CXXMethodDecl>(Import(Proto, Lang_CXX));
  EXPECT_EQ(To->size_overridden_methods(), 1u);
}

TEST_P(ImportFunctions, VirtualFlagShouldBePreservedWhenImportingPrototype) {
  auto Code =
      R"(
      struct B { virtual void f(); };
      void B::f() {}
      )";
  auto Pattern =
      cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
  Decl *FromTU = getTuDecl(Code, Lang_CXX);
  CXXMethodDecl *Proto =
      FirstDeclMatcher<CXXMethodDecl>().match(FromTU, Pattern);
  CXXMethodDecl *Def = LastDeclMatcher<CXXMethodDecl>().match(FromTU, Pattern);

  ASSERT_TRUE(Proto->isVirtual());
  ASSERT_TRUE(Def->isVirtual());
  CXXMethodDecl *To = cast<CXXMethodDecl>(Import(Proto, Lang_CXX));
  EXPECT_TRUE(To->isVirtual());
}

TEST_P(ImportFunctions,
       ImportDefinitionIfThereIsAnExistingDefinitionAndFwdDecl) {
  Decl *ToTU = getToTuDecl(
      R"(
      void f() {}
      void f();
      )",
      Lang_CXX);
  ASSERT_EQ(1u,
            DeclCounterWithPredicate<FunctionDecl>([](const FunctionDecl *FD) {
              return FD->doesThisDeclarationHaveABody();
            }).match(ToTU, functionDecl()));

  Decl *FromTU = getTuDecl("void f() {}", Lang_CXX, "input0.cc");
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, functionDecl());

  Import(FromD, Lang_CXX);

  EXPECT_EQ(1u,
            DeclCounterWithPredicate<FunctionDecl>([](const FunctionDecl *FD) {
              return FD->doesThisDeclarationHaveABody();
            }).match(ToTU, functionDecl()));
}

TEST_P(ImportFunctions, ImportOverriddenMethodTwice) {
  auto Code =
      R"(
      struct B { virtual void f(); };
      struct D:B { void f(); };
      )";
  auto BFP =
      cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
  auto DFP =
      cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))));

  Decl *FromTU0 = getTuDecl(Code, Lang_CXX);
  auto *DF = FirstDeclMatcher<CXXMethodDecl>().match(FromTU0, DFP);
  Import(DF, Lang_CXX);

  Decl *FromTU1 = getTuDecl(Code, Lang_CXX, "input1.cc");
  auto *BF = FirstDeclMatcher<CXXMethodDecl>().match(FromTU1, BFP);
  Import(BF, Lang_CXX);

  auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();

  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFP), 1u);
  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFP), 1u);
}

TEST_P(ImportFunctions, ImportOverriddenMethodTwiceDefinitionFirst) {
  auto CodeWithoutDef =
      R"(
      struct B { virtual void f(); };
      struct D:B { void f(); };
      )";
  auto CodeWithDef =
      R"(
    struct B { virtual void f(){}; };
    struct D:B { void f(){}; };
  )";
  auto BFP =
      cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
  auto DFP =
      cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))));
  auto BFDefP = cxxMethodDecl(
      hasName("f"), hasParent(cxxRecordDecl(hasName("B"))), isDefinition());
  auto DFDefP = cxxMethodDecl(
      hasName("f"), hasParent(cxxRecordDecl(hasName("D"))), isDefinition());
  auto FDefAllP = cxxMethodDecl(hasName("f"), isDefinition());

  {
    Decl *FromTU = getTuDecl(CodeWithDef, Lang_CXX, "input0.cc");
    auto *FromD = FirstDeclMatcher<CXXMethodDecl>().match(FromTU, DFP);
    Import(FromD, Lang_CXX);
  }
  {
    Decl *FromTU = getTuDecl(CodeWithoutDef, Lang_CXX, "input1.cc");
    auto *FromB = FirstDeclMatcher<CXXMethodDecl>().match(FromTU, BFP);
    Import(FromB, Lang_CXX);
  }

  auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();

  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFP), 1u);
  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFP), 1u);
  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFDefP), 1u);
  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFDefP), 1u);
  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, FDefAllP), 2u);
}

TEST_P(ImportFunctions, ImportOverriddenMethodTwiceOutOfClassDef) {
  auto Code =
      R"(
      struct B { virtual void f(); };
      struct D:B { void f(); };
      void B::f(){};
      )";

  auto BFP =
      cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
  auto BFDefP = cxxMethodDecl(
      hasName("f"), hasParent(cxxRecordDecl(hasName("B"))), isDefinition());
  auto DFP = cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))),
                           unless(isDefinition()));

  Decl *FromTU0 = getTuDecl(Code, Lang_CXX);
  auto *D = FirstDeclMatcher<CXXMethodDecl>().match(FromTU0, DFP);
  Import(D, Lang_CXX);

  Decl *FromTU1 = getTuDecl(Code, Lang_CXX, "input1.cc");
  auto *B = FirstDeclMatcher<CXXMethodDecl>().match(FromTU1, BFP);
  Import(B, Lang_CXX);

  auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();

  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFP), 1u);
  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFDefP), 0u);

  auto *ToB = FirstDeclMatcher<CXXRecordDecl>().match(
      ToTU, cxxRecordDecl(hasName("B")));
  auto *ToBFInClass = FirstDeclMatcher<CXXMethodDecl>().match(ToTU, BFP);
  auto *ToBFOutOfClass = FirstDeclMatcher<CXXMethodDecl>().match(
      ToTU, cxxMethodDecl(hasName("f"), isDefinition()));

  // The definition should be out-of-class.
  EXPECT_NE(ToBFInClass, ToBFOutOfClass);
  EXPECT_NE(ToBFInClass->getLexicalDeclContext(),
            ToBFOutOfClass->getLexicalDeclContext());
  EXPECT_EQ(ToBFOutOfClass->getDeclContext(), ToB);
  EXPECT_EQ(ToBFOutOfClass->getLexicalDeclContext(), ToTU);

  // Check that the redecl chain is intact.
  EXPECT_EQ(ToBFOutOfClass->getPreviousDecl(), ToBFInClass);
}

TEST_P(ImportFunctions,
       ImportOverriddenMethodTwiceOutOfClassDefInSeparateCode) {
  auto CodeTU0 =
      R"(
      struct B { virtual void f(); };
      struct D:B { void f(); };
      )";
  auto CodeTU1 =
      R"(
      struct B { virtual void f(); };
      struct D:B { void f(); };
      void B::f(){}
      void D::f(){}
      void foo(B &b, D &d) { b.f(); d.f(); }
      )";

  auto BFP =
      cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("B"))));
  auto BFDefP = cxxMethodDecl(
      hasName("f"), hasParent(cxxRecordDecl(hasName("B"))), isDefinition());
  auto DFP =
      cxxMethodDecl(hasName("f"), hasParent(cxxRecordDecl(hasName("D"))));
  auto DFDefP = cxxMethodDecl(
      hasName("f"), hasParent(cxxRecordDecl(hasName("D"))), isDefinition());
  auto FooDef = functionDecl(hasName("foo"));

  {
    Decl *FromTU0 = getTuDecl(CodeTU0, Lang_CXX, "input0.cc");
    auto *D = FirstDeclMatcher<CXXMethodDecl>().match(FromTU0, DFP);
    Import(D, Lang_CXX);
  }

  {
    Decl *FromTU1 = getTuDecl(CodeTU1, Lang_CXX, "input1.cc");
    auto *Foo = FirstDeclMatcher<FunctionDecl>().match(FromTU1, FooDef);
    Import(Foo, Lang_CXX);
  }

  auto *ToTU = ToAST->getASTContext().getTranslationUnitDecl();

  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFP), 1u);
  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFP), 1u);
  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, BFDefP), 0u);
  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, DFDefP), 0u);

  auto *ToB = FirstDeclMatcher<CXXRecordDecl>().match(
      ToTU, cxxRecordDecl(hasName("B")));
  auto *ToD = FirstDeclMatcher<CXXRecordDecl>().match(
      ToTU, cxxRecordDecl(hasName("D")));
  auto *ToBFInClass = FirstDeclMatcher<CXXMethodDecl>().match(ToTU, BFP);
  auto *ToBFOutOfClass = FirstDeclMatcher<CXXMethodDecl>().match(
      ToTU, cxxMethodDecl(hasName("f"), isDefinition()));
  auto *ToDFInClass = FirstDeclMatcher<CXXMethodDecl>().match(ToTU, DFP);
  auto *ToDFOutOfClass = LastDeclMatcher<CXXMethodDecl>().match(
      ToTU, cxxMethodDecl(hasName("f"), isDefinition()));

  // The definition should be out-of-class.
  EXPECT_NE(ToBFInClass, ToBFOutOfClass);
  EXPECT_NE(ToBFInClass->getLexicalDeclContext(),
            ToBFOutOfClass->getLexicalDeclContext());
  EXPECT_EQ(ToBFOutOfClass->getDeclContext(), ToB);
  EXPECT_EQ(ToBFOutOfClass->getLexicalDeclContext(), ToTU);

  EXPECT_NE(ToDFInClass, ToDFOutOfClass);
  EXPECT_NE(ToDFInClass->getLexicalDeclContext(),
            ToDFOutOfClass->getLexicalDeclContext());
  EXPECT_EQ(ToDFOutOfClass->getDeclContext(), ToD);
  EXPECT_EQ(ToDFOutOfClass->getLexicalDeclContext(), ToTU);

  // Check that the redecl chain is intact.
  EXPECT_EQ(ToBFOutOfClass->getPreviousDecl(), ToBFInClass);
  EXPECT_EQ(ToDFOutOfClass->getPreviousDecl(), ToDFInClass);
}

TEST_P(ASTImporterOptionSpecificTestBase, ImportVariableChainInC) {
    std::string Code = "static int v; static int v = 0;";
    auto Pattern = varDecl(hasName("v"));

    TranslationUnitDecl *FromTu = getTuDecl(Code, Lang_C, "input0.c");

    auto *From0 = FirstDeclMatcher<VarDecl>().match(FromTu, Pattern);
    auto *From1 = LastDeclMatcher<VarDecl>().match(FromTu, Pattern);

    auto *To0 = Import(From0, Lang_C);
    auto *To1 = Import(From1, Lang_C);

    EXPECT_TRUE(To0);
    ASSERT_TRUE(To1);
    EXPECT_NE(To0, To1);
    EXPECT_EQ(To1->getPreviousDecl(), To0);
}

TEST_P(ImportFunctions, ImportFromDifferentScopedAnonNamespace) {
  TranslationUnitDecl *FromTu = getTuDecl(
      "namespace NS0 { namespace { void f(); } }"
      "namespace NS1 { namespace { void f(); } }",
      Lang_CXX, "input0.cc");
  auto Pattern = functionDecl(hasName("f"));

  auto *FromF0 = FirstDeclMatcher<FunctionDecl>().match(FromTu, Pattern);
  auto *FromF1 = LastDeclMatcher<FunctionDecl>().match(FromTu, Pattern);

  auto *ToF0 = Import(FromF0, Lang_CXX);
  auto *ToF1 = Import(FromF1, Lang_CXX);

  EXPECT_TRUE(ToF0);
  ASSERT_TRUE(ToF1);
  EXPECT_NE(ToF0, ToF1);
  EXPECT_FALSE(ToF1->getPreviousDecl());
}

TEST_P(ImportFunctions, ImportFunctionFromUnnamedNamespace) {
  {
    Decl *FromTU = getTuDecl("namespace { void f() {} } void g0() { f(); }",
                             Lang_CXX, "input0.cc");
    auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
        FromTU, functionDecl(hasName("g0")));

    Import(FromD, Lang_CXX);
  }
  {
    Decl *FromTU =
        getTuDecl("namespace { void f() { int a; } } void g1() { f(); }",
                  Lang_CXX, "input1.cc");
    auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
        FromTU, functionDecl(hasName("g1")));
    Import(FromD, Lang_CXX);
  }

  Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, functionDecl(hasName("f"))),
            2u);
}

TEST_P(ImportFunctions, ImportImplicitFunctionsInLambda) {
  Decl *FromTU = getTuDecl(
      R"(
      void foo() {
        (void)[]() { ; };
      }
      )",
      Lang_CXX11);
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
      FromTU, functionDecl(hasName("foo")));
  auto *ToD = Import(FromD, Lang_CXX);
  EXPECT_TRUE(ToD);
  CXXRecordDecl *LambdaRec =
      cast<LambdaExpr>(cast<CStyleCastExpr>(
                           *cast<CompoundStmt>(ToD->getBody())->body_begin())
                           ->getSubExpr())
          ->getLambdaClass();
  EXPECT_TRUE(LambdaRec->getDestructor());
}

TEST_P(ImportFunctions,
       CallExprOfMemberFunctionTemplateWithExplicitTemplateArgs) {
  Decl *FromTU = getTuDecl(
      R"(
      struct X {
        template <typename T>
        void foo(){}
      };
      void f() {
        X x;
        x.foo<int>();
      }
      )",
      Lang_CXX);
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
      FromTU, functionDecl(hasName("f")));
  auto *ToD = Import(FromD, Lang_CXX);
  EXPECT_TRUE(ToD);
  EXPECT_TRUE(MatchVerifier<FunctionDecl>().match(
      ToD, functionDecl(hasName("f"), hasDescendant(declRefExpr()))));
}

TEST_P(ImportFunctions,
       DependentCallExprOfMemberFunctionTemplateWithExplicitTemplateArgs) {
  Decl *FromTU = getTuDecl(
      R"(
      struct X {
        template <typename T>
        void foo(){}
      };
      template <typename T>
      void f() {
        X x;
        x.foo<T>();
      }
      void g() {
        f<int>();
      }
      )",
      Lang_CXX);
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
      FromTU, functionDecl(hasName("g")));
  auto *ToD = Import(FromD, Lang_CXX);
  EXPECT_TRUE(ToD);
  Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  EXPECT_TRUE(MatchVerifier<TranslationUnitDecl>().match(
      ToTU, translationUnitDecl(hasDescendant(
                functionDecl(hasName("f"), hasDescendant(declRefExpr()))))));
}

struct ImportFunctionTemplates : ASTImporterOptionSpecificTestBase {};

TEST_P(ImportFunctionTemplates, ImportFunctionTemplateInRecordDeclTwice) {
  auto Code =
      R"(
      class X {
        template <class T>
        void f(T t);
      };
      )";
  Decl *FromTU1 = getTuDecl(Code, Lang_CXX, "input1.cc");
  auto *FromD1 = FirstDeclMatcher<FunctionTemplateDecl>().match(
      FromTU1, functionTemplateDecl(hasName("f")));
  auto *ToD1 = Import(FromD1, Lang_CXX);
  Decl *FromTU2 = getTuDecl(Code, Lang_CXX, "input2.cc");
  auto *FromD2 = FirstDeclMatcher<FunctionTemplateDecl>().match(
      FromTU2, functionTemplateDecl(hasName("f")));
  auto *ToD2 = Import(FromD2, Lang_CXX);
  EXPECT_EQ(ToD1, ToD2);
}

TEST_P(ImportFunctionTemplates,
       ImportFunctionTemplateWithDefInRecordDeclTwice) {
  auto Code =
      R"(
      class X {
        template <class T>
        void f(T t);
      };
      template <class T>
      void X::f(T t) {};
      )";
  Decl *FromTU1 = getTuDecl(Code, Lang_CXX, "input1.cc");
  auto *FromD1 = FirstDeclMatcher<FunctionTemplateDecl>().match(
      FromTU1, functionTemplateDecl(hasName("f")));
  auto *ToD1 = Import(FromD1, Lang_CXX);
  Decl *FromTU2 = getTuDecl(Code, Lang_CXX, "input2.cc");
  auto *FromD2 = FirstDeclMatcher<FunctionTemplateDecl>().match(
      FromTU2, functionTemplateDecl(hasName("f")));
  auto *ToD2 = Import(FromD2, Lang_CXX);
  EXPECT_EQ(ToD1, ToD2);
}

TEST_P(ImportFunctionTemplates,
       ImportFunctionWhenThereIsAFunTemplateWithSameName) {
  getToTuDecl(
      R"(
      template <typename T>
      void foo(T) {}
      void foo();
      )",
      Lang_CXX);
  Decl *FromTU = getTuDecl("void foo();", Lang_CXX);
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(
      FromTU, functionDecl(hasName("foo")));
  auto *ImportedD = Import(FromD, Lang_CXX);
  EXPECT_TRUE(ImportedD);
}

TEST_P(ImportFunctionTemplates,
       ImportConstructorWhenThereIsAFunTemplateWithSameName) {
  auto Code =
      R"(
      struct Foo {
        template <typename T>
        Foo(T) {}
        Foo();
      };
      )";
  getToTuDecl(Code, Lang_CXX);
  Decl *FromTU = getTuDecl(Code, Lang_CXX);
  auto *FromD =
      LastDeclMatcher<CXXConstructorDecl>().match(FromTU, cxxConstructorDecl());
  auto *ImportedD = Import(FromD, Lang_CXX);
  EXPECT_TRUE(ImportedD);
}

TEST_P(ImportFunctionTemplates,
       ImportOperatorWhenThereIsAFunTemplateWithSameName) {
  getToTuDecl(
      R"(
      template <typename T>
      void operator<(T,T) {}
      struct X{};
      void operator<(X, X);
      )",
      Lang_CXX);
  Decl *FromTU = getTuDecl(
      R"(
      struct X{};
      void operator<(X, X);
      )",
      Lang_CXX);
  auto *FromD = LastDeclMatcher<FunctionDecl>().match(
      FromTU, functionDecl(hasOverloadedOperatorName("<")));
  auto *ImportedD = Import(FromD, Lang_CXX);
  EXPECT_TRUE(ImportedD);
}

struct ImportFriendFunctions : ImportFunctions {};

TEST_P(ImportFriendFunctions, ImportFriendFunctionRedeclChainProto) {
  auto Pattern = functionDecl(hasName("f"));

  Decl *FromTU = getTuDecl("struct X { friend void f(); };"
                           "void f();",
                           Lang_CXX,
                           "input0.cc");
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);

  auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX));
  Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
  EXPECT_FALSE(ImportedD->doesThisDeclarationHaveABody());
  auto *ToFD = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
  EXPECT_FALSE(ToFD->doesThisDeclarationHaveABody());
  EXPECT_EQ(ToFD->getPreviousDecl(), ImportedD);
}

TEST_P(ImportFriendFunctions,
       ImportFriendFunctionRedeclChainProto_OutOfClassProtoFirst) {
  auto Pattern = functionDecl(hasName("f"));

  Decl *FromTU = getTuDecl("void f();"
                           "struct X { friend void f(); };",
                           Lang_CXX, "input0.cc");
  auto FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);

  auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX));
  Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
  EXPECT_FALSE(ImportedD->doesThisDeclarationHaveABody());
  auto *ToFD = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
  EXPECT_FALSE(ToFD->doesThisDeclarationHaveABody());
  EXPECT_EQ(ToFD->getPreviousDecl(), ImportedD);
}

TEST_P(ImportFriendFunctions, ImportFriendFunctionRedeclChainDef) {
  auto Pattern = functionDecl(hasName("f"));

  Decl *FromTU = getTuDecl("struct X { friend void f(){} };"
                           "void f();",
                           Lang_CXX,
                           "input0.cc");
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);

  auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX));
  Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
  EXPECT_TRUE(ImportedD->doesThisDeclarationHaveABody());
  auto *ToFD = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
  EXPECT_FALSE(ToFD->doesThisDeclarationHaveABody());
  EXPECT_EQ(ToFD->getPreviousDecl(), ImportedD);
}

TEST_P(ImportFriendFunctions,
       ImportFriendFunctionRedeclChainDef_OutOfClassDef) {
  auto Pattern = functionDecl(hasName("f"));

  Decl *FromTU = getTuDecl("struct X { friend void f(); };"
                           "void f(){}",
                           Lang_CXX, "input0.cc");
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);

  auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX));
  Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
  EXPECT_FALSE(ImportedD->doesThisDeclarationHaveABody());
  auto *ToFD = LastDeclMatcher<FunctionDecl>().match(ToTU, Pattern);
  EXPECT_TRUE(ToFD->doesThisDeclarationHaveABody());
  EXPECT_EQ(ToFD->getPreviousDecl(), ImportedD);
}

TEST_P(ImportFriendFunctions, ImportFriendFunctionRedeclChainDefWithClass) {
  auto Pattern = functionDecl(hasName("f"));

  Decl *FromTU = getTuDecl(
      R"(
        class X;
        void f(X *x){}
        class X{
        friend void f(X *x);
        };
      )",
      Lang_CXX, "input0.cc");
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);

  auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX));
  Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
  EXPECT_TRUE(ImportedD->doesThisDeclarationHaveABody());
  auto *InClassFD = cast<FunctionDecl>(FirstDeclMatcher<FriendDecl>()
                                              .match(ToTU, friendDecl())
                                              ->getFriendDecl());
  EXPECT_FALSE(InClassFD->doesThisDeclarationHaveABody());
  EXPECT_EQ(InClassFD->getPreviousDecl(), ImportedD);
  // The parameters must refer the same type
  EXPECT_EQ((*InClassFD->param_begin())->getOriginalType(),
            (*ImportedD->param_begin())->getOriginalType());
}

TEST_P(ImportFriendFunctions,
       ImportFriendFunctionRedeclChainDefWithClass_ImportTheProto) {
  auto Pattern = functionDecl(hasName("f"));

  Decl *FromTU = getTuDecl(
      R"(
        class X;
        void f(X *x){}
        class X{
        friend void f(X *x);
        };
      )",
      Lang_CXX, "input0.cc");
  auto *FromD = LastDeclMatcher<FunctionDecl>().match(FromTU, Pattern);

  auto *ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX));
  Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
  EXPECT_FALSE(ImportedD->doesThisDeclarationHaveABody());
  auto *OutOfClassFD = FirstDeclMatcher<FunctionDecl>().match(
      ToTU, functionDecl(unless(hasParent(friendDecl()))));

  EXPECT_TRUE(OutOfClassFD->doesThisDeclarationHaveABody());
  EXPECT_EQ(ImportedD->getPreviousDecl(), OutOfClassFD);
  // The parameters must refer the same type
  EXPECT_EQ((*OutOfClassFD->param_begin())->getOriginalType(),
            (*ImportedD->param_begin())->getOriginalType());
}

TEST_P(ImportFriendFunctions, ImportFriendFunctionFromMultipleTU) {
  auto Pattern = functionDecl(hasName("f"));

  FunctionDecl *ImportedD;
  {
    Decl *FromTU =
        getTuDecl("struct X { friend void f(){} };", Lang_CXX, "input0.cc");
    auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
    ImportedD = cast<FunctionDecl>(Import(FromD, Lang_CXX));
  }
  FunctionDecl *ImportedD1;
  {
    Decl *FromTU = getTuDecl("void f();", Lang_CXX, "input1.cc");
    auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, Pattern);
    ImportedD1 = cast<FunctionDecl>(Import(FromD, Lang_CXX));
  }

  Decl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  ASSERT_EQ(DeclCounter<FunctionDecl>().match(ToTU, Pattern), 2u);
  EXPECT_TRUE(ImportedD->doesThisDeclarationHaveABody());
  EXPECT_FALSE(ImportedD1->doesThisDeclarationHaveABody());
  EXPECT_EQ(ImportedD1->getPreviousDecl(), ImportedD);
}

TEST_P(ImportFriendFunctions, Lookup) {
  auto FunctionPattern = functionDecl(hasName("f"));
  auto ClassPattern = cxxRecordDecl(hasName("X"));

  TranslationUnitDecl *FromTU =
      getTuDecl("struct X { friend void f(); };", Lang_CXX, "input0.cc");
  auto *FromD = FirstDeclMatcher<FunctionDecl>().match(FromTU, FunctionPattern);
  ASSERT_TRUE(FromD->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
  ASSERT_FALSE(FromD->isInIdentifierNamespace(Decl::IDNS_Ordinary));
  {
    auto FromName = FromD->getDeclName();
    auto *Class = FirstDeclMatcher<CXXRecordDecl>().match(FromTU, ClassPattern);
    auto LookupRes = Class->noload_lookup(FromName);
    ASSERT_EQ(LookupRes.size(), 0u);
    LookupRes = FromTU->noload_lookup(FromName);
    ASSERT_EQ(LookupRes.size(), 1u);
  }

  auto *ToD = cast<FunctionDecl>(Import(FromD, Lang_CXX));
  auto ToName = ToD->getDeclName();

  TranslationUnitDecl *ToTU = ToAST->getASTContext().getTranslationUnitDecl();
  auto *Class = FirstDeclMatcher<CXXRecordDecl>().match(ToTU, ClassPattern);
  auto LookupRes = Class->noload_lookup(ToName);
  EXPECT_EQ(LookupRes.size(), 0u);
  LookupRes = ToTU->noload_lookup(ToName);
  EXPECT_EQ(LookupRes.size(), 1u);

  EXPECT_EQ(DeclCounter<FunctionDecl>().match(ToTU, FunctionPattern), 1u);
  auto *To0 = FirstDeclMatcher<FunctionDecl>().match(ToTU, FunctionPattern);
  EXPECT_TRUE(To0->isInIdentifierNamespace(Decl::IDNS_OrdinaryFriend));
  EXPECT_FALSE(To0->isInIdentifierNamespace(Decl::IDNS_Ordinary));
}

TEST_P(ImportFriendFunctions, DISABLED_LookupWithProtoAfter) {
  auto FunctionPattern = functionDecl(hasName("f"));
  auto ClassPattern = cxxRecordDecl(hasName("X"));

  TranslationUnitDecl *FromTU = getTuDecl(
      "struct X { friend void f(); };"
      // This proto decl makes f available to normal
      // lookup, otherwise it is hidden.
      // Normal C++ lookup (implemented in
      // `clang::Sema::CppLookupName()` and in `LookupDirect()`)
      // returns the found `NamedDecl` only if the set IDNS is matched
      "void f();",
      Lang_CXX, "input0.cc");
  auto *FromFriend =
      FirstDeclMatcher<FunctionDecl>().match(FromTU, FunctionPattern);
  auto *FromNormal