// Copyright 2022 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include <csignal>
#include <cstddef>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <filesystem>  // NOLINT
#include <string>
#include <system_error>  // NOLINT
#include <tuple>
#include <utility>
#include <vector>

#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/container/flat_hash_map.h"
#include "absl/strings/str_cat.h"
#include "absl/strings/str_format.h"
#include "absl/strings/string_view.h"
#include "absl/strings/substitute.h"
#include "absl/time/clock.h"
#include "absl/time/time.h"
#include "./common/logging.h"
#include "./common/temp_dir.h"
#include "./e2e_tests/test_binary_util.h"
#include "./fuzztest/internal/escaping.h"
#include "./fuzztest/internal/io.h"
#include "./fuzztest/internal/logging.h"
#include "./fuzztest/internal/printer.h"
#include "./fuzztest/internal/serialization.h"
#include "./fuzztest/internal/subprocess.h"
#include "./fuzztest/internal/type_support.h"
#include "re2/re2.h"

#define EXPECT_THAT_LOG(log, matcher)                                  \
  EXPECT_TRUE(testing::Value(log, matcher))                            \
      << "Matcher: " << testing::DescribeMatcher<std::string>(matcher) \
      << "\nContents of " #log ":\n"                                   \
      << log
#define ASSERT_THAT_LOG(log, matcher)                                  \
  ASSERT_TRUE(testing::Value(log, matcher))                            \
      << "Matcher: " << testing::DescribeMatcher<std::string>(matcher) \
      << "\nContents of " #log ":\n"                                   \
      << log

namespace fuzztest::internal {
namespace {

using ::fuzztest::domain_implementor::PrintMode;
using ::testing::_;
using ::testing::AllOf;
using ::testing::AnyOf;
using ::testing::ContainsRegex;
using ::testing::Eq;
using ::testing::FieldsAre;
using ::testing::HasSubstr;
using ::testing::IsEmpty;
using ::testing::IsSubsetOf;
using ::testing::Le;
using ::testing::Ne;
using ::testing::Not;
using ::testing::Optional;
using ::testing::SizeIs;
using ::testing::StartsWith;

constexpr absl::string_view kDefaultTargetBinary =
    "testdata/fuzz_tests_for_functional_testing";

absl::flat_hash_map<std::string, std::string> WithTestSanitizerOptions(
    absl::flat_hash_map<std::string, std::string> env) {
  if (!env.contains("ASAN_OPTIONS"))
    env["ASAN_OPTIONS"] = "handle_abort=0:handle_sigfpe=0:detect_leaks=0";
  if (!env.contains("MSAN_OPTIONS"))
    env["MSAN_OPTIONS"] = "handle_abort=0:handle_sigfpe=0";
  return env;
}

void ExpectTargetAbort(TerminationStatus status, absl::string_view std_err) {
#ifdef FUZZTEST_USE_CENTIPEDE
  EXPECT_THAT(status, Ne(ExitCode(0)));
  EXPECT_TRUE(RE2::PartialMatch(std_err,
                                absl::StrCat("[Ee]xit code\\s*:\\s*", SIGABRT)))
      << std_err;
#else
  EXPECT_THAT(status, Eq(Signal(SIGABRT)));
#endif
}

int CountSubstrs(absl::string_view haystack, absl::string_view needle) {
  int count = 0;
  while (true) {
    size_t pos = haystack.find(needle);
    if (pos == haystack.npos) return count;
    ++count;
    haystack.remove_prefix(pos + needle.size());
  }
}

// Counts the number of times the target binary has been run. Needed because
// Centipede runs the binary multiple times.
int CountTargetRuns(absl::string_view std_err) {
  return CountSubstrs(std_err, "FuzzTest functional test target run");
}

class UnitTestModeTest : public ::testing::Test {
 protected:
  RunResults Run(
      absl::string_view test_filter,
      absl::string_view target_binary = kDefaultTargetBinary,
      const absl::flat_hash_map<std::string, std::string>& env = {},
      absl::flat_hash_map<std::string, std::string> fuzzer_flags = {}) {
    fuzzer_flags["print_subprocess_log"] = "true";
    fuzzer_flags["unguided"] = "true";
    if (!fuzzer_flags.contains("fuzz_for")) {
      fuzzer_flags["fuzz_for"] = "10s";
    }
    RunOptions run_options;
    run_options.flags = {
        {GTEST_FLAG_PREFIX_ "filter", std::string(test_filter)},
        {"symbolize_stacktrace", "0"}};
    run_options.fuzztest_flags = std::move(fuzzer_flags);
    run_options.env = WithTestSanitizerOptions(env);
    return RunBinary(BinaryPath(target_binary), run_options);
  }
};

TEST_F(UnitTestModeTest, PassingTestPassesInUnitTestingMode) {
  auto [status, std_out, std_err] = Run("MySuite.PassesWithPositiveInput");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, InvalidSeedsAreSkippedAndReported) {
  auto [status, std_out, std_err] =
      Run(/*test_filter=*/"*",
          /*target_binary=*/"testdata/fuzz_tests_with_invalid_seeds");
  EXPECT_THAT_LOG(std_err, HasSubstr("[!] Skipping WithSeeds() value in"));
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("Could not turn value into corpus type:\n{17}"));
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("The value 17 is not InRange(0, 10):\n{17}"));
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("The value 8 is not InRange(10, 20):\n{7, 8}"));
  // Valid seeds are not reported.
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("{6}")));
  // Tests should still run.
  EXPECT_THAT_LOG(std_out, HasSubstr("[  PASSED  ] 4 tests."));
  EXPECT_THAT(status, ExitCode(0));
}

TEST_F(UnitTestModeTest, CorpusIsMutatedInUnitTestMode) {
  auto [status, std_out, std_err] = Run("MySuite.PassesString");
  EXPECT_THAT_LOG(std_err, HasSubstr("==<<Saw size=0>>=="));
  EXPECT_THAT_LOG(std_err, HasSubstr("==<<Saw size=1>>=="));
  EXPECT_THAT_LOG(std_err, HasSubstr("==<<Saw size=2>>=="));
  EXPECT_THAT_LOG(std_err, HasSubstr("==<<Saw size=3>>=="));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, UnitTestModeLimitsNumberOfIterationsByWallTime) {
  // We run this in unittest mode to check that we reduce the number of
  // iterations to accommodate for the longer run time.
  auto [status, std_out, std_err] = Run("MySuite.OneIterationTakesTooMuchTime");
  EXPECT_THAT_LOG(
      std_out, HasSubstr("[       OK ] MySuite.OneIterationTakesTooMuchTime"));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

RE2 MakeReproducerRegex(absl::string_view suite_name,
                        absl::string_view test_name, absl::string_view args) {
  return RE2(
      absl::Substitute(R"re(TEST\($0, $1.*\) {\n.*$1\(\n.*$2.*\n.*\).*\n.*})re",
                       suite_name, test_name, args));
}

std::string RemoveReproducer(std::string str, absl::string_view suite_name,
                             absl::string_view test_name,
                             absl::string_view args) {
  EXPECT_TRUE(
      RE2::Replace(&str, MakeReproducerRegex(suite_name, test_name, args), ""));
  return str;
}

// Matches strings that contain a reproducer test.
//
// For example, `HasReproducerTest("MySuite", "MyTest", "1, \"foo\"")` would
// match the following string:
//
//   TEST(MySuite, MyTestRegression) {
//     MyTest(
//       1, "foo"
//     );
//   }
//
// The parameters `suite_name`, `test_name`, and `args` are regular expressions;
// make sure they are properly escaped!
MATCHER_P3(HasReproducerTest, suite_name, test_name, args, "") {
  // `ContainsRegex` doesn't support the following regex externally.
  return RE2::PartialMatch(arg,
                           MakeReproducerRegex(suite_name, test_name, args));
}

void GoogleTestExpectationsDontAbortInUnitTestModeImpl(
    const RunResults& run_results) {
  const auto& [status, std_out, std_err] = run_results;
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  // We expect both to run without crashing.
  EXPECT_THAT_LOG(std_out, HasSubstr("[  FAILED  ] MySuite.GoogleTestExpect"));
  EXPECT_THAT_LOG(std_out, HasSubstr("[  FAILED  ] MySuite.GoogleTestAssert"));
  EXPECT_THAT(status, Ne(ExitCode(0)));

#ifndef FUZZTEST_USE_CENTIPEDE
  // There is the gtest stack on stdout, and no stack on stderr.
  EXPECT_THAT_LOG(std_out, AllOf(HasSubstr("GoogleTestExpect("),
                                 HasSubstr("GoogleTestAssert(")));
  // We remove the reproducer first because it also contains the function name.
  EXPECT_THAT(RemoveReproducer(RemoveReproducer(std_err, "MySuite",
                                                "GoogleTestExpect", ".*"),
                               "MySuite", "GoogleTestAssert", ".*"),
              AllOf(Not(HasSubstr("GoogleTestExpect(")),
                    Not(HasSubstr("GoogleTestAssert("))));
#endif

  // There is no repro example on stdout, and there is one on stderr.
  EXPECT_THAT_LOG(
      std_out,
      AllOf(Not(HasReproducerTest("MySuite", "GoogleTestExpect", ".*")),
            Not(HasReproducerTest("MySuite", "GoogleTestAssert", ".*"))));
  EXPECT_THAT_LOG(
      std_err, AllOf(HasReproducerTest("MySuite", "GoogleTestExpect", ".*"),
                     HasReproducerTest("MySuite", "GoogleTestAssert", ".*")));
}

TEST_F(UnitTestModeTest, GoogleTestExpectationsDontAbortInUnitTestMode) {
  GoogleTestExpectationsDontAbortInUnitTestModeImpl(
      Run("MySuite.GoogleTestExpect:MySuite.GoogleTestAssert"));
}

TEST_F(UnitTestModeTest,
       GoogleTestExpectationsDontAbortInUnitTestModeWhenAsanHandlesAbort) {
  GoogleTestExpectationsDontAbortInUnitTestModeImpl(Run(
      "MySuite.GoogleTestExpect:MySuite.GoogleTestAssert", kDefaultTargetBinary,
      /*env=*/{{"ASAN_OPTIONS", "handle_abort=2"}}));
}

TEST_F(UnitTestModeTest, GlobalEnvironmentGoesThroughCompleteLifecycle) {
  auto [status, std_out, std_err] = Run("MySuite.GoogleTestNeverFails");
  EXPECT_GT(CountSubstrs(std_err, "<<GlobalEnvironment::GlobalEnvironment()>>"),
            0);
  EXPECT_EQ(
      CountSubstrs(std_err, "<<GlobalEnvironment::GlobalEnvironment()>>"),
      CountSubstrs(std_err, "<<GlobalEnvironment::~GlobalEnvironment()>>"));
  EXPECT_GT(CountSubstrs(std_err, "<<GlobalEnvironment::SetUp()>>"), 0);
  EXPECT_EQ(CountSubstrs(std_err, "<<GlobalEnvironment::SetUp()>>"),
            CountSubstrs(std_err, "<<GlobalEnvironment::TearDown()>>"));
}

TEST_F(UnitTestModeTest, FixtureGoesThroughCompleteLifecycle) {
  auto [status, std_out, std_err] = Run("FixtureTest.NeverFails");
  EXPECT_GT(CountSubstrs(std_err, "<<FixtureTest::FixtureTest()>>"), 0);
  EXPECT_EQ(CountSubstrs(std_err, "<<FixtureTest::FixtureTest()>>"),
            CountSubstrs(std_err, "<<FixtureTest::~FixtureTest()>>"));
}

TEST_F(UnitTestModeTest,
       GoogleTestPerIterationFixtureInstantiatedOncePerIteration) {
  auto [status, std_out, std_err] =
      Run("CallCountPerIteration.CallCountIsAlwaysIncrementedFromInitialValue");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest,
       GoogleTestPerFuzzTestFixtureInstantiatedOncePerFuzzTest) {
  auto [status, std_out, std_err] =
      Run("CallCountPerFuzzTest.CallCountPerFuzzTestEqualsToGlobalCount");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, GoogleTestStaticTestSuiteFunctionsCalledInBalance) {
  auto [status, std_out, std_err] =
      Run("CallCountPerFuzzTest.CallCountPerFuzzTestEqualsToGlobalCount:"
          "CallCountPerFuzzTest.NeverFails");
  EXPECT_GT(CountSubstrs(std_err, "<<CallCountGoogleTest::SetUpTestSuite()>>"),
            0);
  EXPECT_EQ(
      CountSubstrs(std_err, "<<CallCountGoogleTest::SetUpTestSuite()>>"),
      CountSubstrs(std_err, "<<CallCountGoogleTest::TearDownTestSuite()>>"));
}

TEST_F(UnitTestModeTest, GoogleTestWorksWithProtoExtensionsUsedInSeeds) {
  auto [status, std_out, std_err] = Run("MySuite.CheckProtoExtensions");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("Uses proto extensions"));
}

TEST_F(UnitTestModeTest, UnitTestAndFuzzTestCanShareSuiteName) {
  auto [status, std_out, std_err] =
      Run("SharedSuite.WorksAsUnitTest:SharedSuite.WorksAsFuzzTest");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, RepeatedFieldsHaveMinSizeWhenInitialized) {
  auto [status, std_out, std_err] = Run("MySuite.RepeatedFieldHasMinimumSize");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, OptionalProtoFieldCanHaveNoValue) {
  auto [status, std_out, std_err] = Run("MySuite.FailsWhenFieldI32HasNoValue");
  ExpectTargetAbort(status, std_err);
}

TEST_F(UnitTestModeTest, OptionalProtoFieldThatIsUnsetNeverHasValue) {
  auto [status, std_out, std_err] = Run("MySuite.FailsWhenFieldI64HasValue");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, ProtoFieldsThatAreUnsetNeverHaveValue) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhen64IntegralFieldsHaveValues");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest,
       ProtoFieldThatAreCustomizedAndAlwaysSetHaveCorrectValue) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenFieldsOfTypeDoubleHasNoValue");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, ProtoFieldsThatAreAlwaysSetAlwaysHaveValue) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhen64IntegralFieldsHaveNoValues");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, CanCustomizeProtoFieldsWithTransformers) {
  auto [status, std_out, std_err] =
      Run("MySuite."
          "FailsIfRepeatedEnumsHaveZeroValueAndOptionalEnumHasNonZeroValue");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest,
       RequiredProtoFieldWillBeSetWhenNullnessIsNotCustomized) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenRequiredInt32FieldHasNoValue");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, RequiredProtoFieldThatIsNotAlwaysSetCanHaveNoValue) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenRequiredEnumFieldHasNoValue");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("cannot have null values"));
}

TEST_F(UnitTestModeTest, OptionalProtoFieldThatIsNotAlwaysSetCanHaveNoValue) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenOptionalFieldU32HasNoValue");
  ExpectTargetAbort(status, std_err);
}

TEST_F(UnitTestModeTest, ProtobufOfMutatesTheProto) {
  auto [status, std_out, std_err] = Run("MySuite.FailsWhenI32IsSet");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("The field i32 is set!"));
}

TEST_F(UnitTestModeTest, ProtobufEnumEqualsLabel4) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsIfProtobufEnumEqualsLabel4");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(
      std_err,
      HasSubstr("argument 0: fuzztest::internal::TestProtobuf::Label4"));
}

TEST_F(UnitTestModeTest, WorksWithRecursiveStructs) {
  auto [status, std_out, std_err] = Run("MySuite.WorksWithRecursiveStructs");
  ExpectTargetAbort(status, std_err);
  // Nullptr has multiple possible human-readable representations.
  EXPECT_THAT_LOG(std_err,
                  AnyOf(HasSubstr("argument 0: LinkedList{0, 1}"),
                        HasSubstr("argument 0: LinkedList{(nil), 1}")));
}

TEST_F(UnitTestModeTest, WorksWithStructsWithConstructors) {
  auto [status, std_out, std_err] =
      Run("MySuite.WorksWithStructsWithConstructors");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: HasConstructor{1, \"abc\"}"));
}

TEST_F(UnitTestModeTest, WorksWithStructsWithEmptyTuples) {
  auto [status, std_out, std_err] =
      Run("MySuite.WorksWithStructsWithEmptyTuples");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: ContainsEmptyTuple{}"));
}

TEST_F(UnitTestModeTest, WorksWithEmptyStructs) {
  auto [status, std_out, std_err] = Run("MySuite.WorksWithEmptyStructs");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: Empty{}"));
}

TEST_F(UnitTestModeTest, WorksWithStructsWithEmptyFields) {
  auto [status, std_out, std_err] =
      Run("MySuite.WorksWithStructsWithEmptyFields");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: ContainsEmpty{Empty{}}"));
}

TEST_F(UnitTestModeTest, WorksWithEmptyInheritance) {
  auto [status, std_out, std_err] = Run("MySuite.WorksWithEmptyInheritance");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: Child{0, \"abc\"}"));
}

TEST_F(UnitTestModeTest, ArbitraryWorksWithEmptyInheritance) {
  auto [status, std_out, std_err] =
      Run("MySuite.ArbitraryWorksWithEmptyInheritance");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0:"));
}

TEST_F(UnitTestModeTest, FlatMapCorrectlyPrintsValues) {
  auto [status, std_out, std_err] = Run("MySuite.FlatMapCorrectlyPrintsValues");
  ExpectTargetAbort(status, std_err);
  // This is the argument to the output domain.
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: {\"AAA\", \"BBB\"}"));
  // This is the argument to the input domain.
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("argument 0: 3")));
}

TEST_F(UnitTestModeTest, CustomSourceCodePrinterCorrectlyPrintsValue) {
  auto [status, std_out, std_err] =
      Run("MySuite.CustomSourceCodePrinterCorrectlyPrintsValue");
  ExpectTargetAbort(status, std_err);
  // This is the argument to the output domain.
  EXPECT_THAT_LOG(
      std_err,
      HasSubstr("MyCustomPrintableTestType::BuildWithValue(\"abcd\")"));
  // This is the argument to the input domain.
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("argument 0: \"abcd\"")));
  EXPECT_THAT_LOG(
      std_err, HasSubstr("argument 0: MyCustomPrintableTestType - input=abcd"));
}

TEST_F(UnitTestModeTest, PrintsVeryLongInputsTrimmed) {
  auto [status, std_out, std_err] = Run("MySuite.LongInput");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("65 ...<value too long>"));
  EXPECT_THAT_LOG(std_err, HasSubstr("A ...<value too long>"));
}

TEST_F(UnitTestModeTest, PropertyFunctionAcceptsTupleOfItsSingleParameter) {
  auto [status, std_out, std_err] = Run("MySuite.UnpacksTupleOfOne");
  ExpectTargetAbort(status, std_err);
}

TEST_F(UnitTestModeTest, PropertyFunctionAcceptsTupleOfItsThreeParameters) {
  auto [status, std_out, std_err] = Run("MySuite.UnpacksTupleOfThree");
  ExpectTargetAbort(status, std_err);
}

TEST_F(UnitTestModeTest, PropertyFunctionAcceptsTupleContainingTuple) {
  auto [status, std_out, std_err] = Run("MySuite.UnpacksTupleContainingTuple");
  ExpectTargetAbort(status, std_err);
}

TEST_F(UnitTestModeTest, ProtoFieldsCanBeAlwaysSet) {
  auto [status, std_out, std_err] = Run("MySuite.FailsWhenSubprotoIsNull");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, ProtoFieldsCanBeUnset) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenSubprotoFieldsAreSet");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, RepeatedProtoFieldsCanBeCustomized) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenRepeatedSubprotoIsSmallOrHasAnEmptyElement");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, DefaultOptionalPolicyAppliesToAllOptionalFields) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenAnyOptionalFieldsHaveValue");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(
    UnitTestModeTest,
    DefaultOptionalPolicyAppliesToAllOptionalFieldsWithoutOverwrittenDomain) {
  auto [status, std_out, std_err] = Run(
      "MySuite."
      "FailsWhenAnyOptionalFieldsHaveValueButNotFieldsWithOverwrittenDomain");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(
    UnitTestModeTest,
    DefaultOptionalPolicyAppliesToAllOptionalFieldsWithoutOverwrittenPolicy) {
  auto [status, std_out, std_err] = Run(
      "MySuite."
      "FailsWhenAnyOptionalFieldsHaveValueButNotFieldsWithOverwrittenPolicy");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, DetectsRecursiveStructureIfOptionalsSetByDefault) {
  auto [status, std_out, std_err] = Run("MySuite.FailsIfCantInitializeProto");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("recursive fields"));
}

TEST_F(UnitTestModeTest, InitializesRequiredFieldsEvenIfTheyAreRecursive) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailIfRequiredRecursiveFieldsAreUnset");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest,
       AvoidsFailureIfSetByDefaultPolicyIsOverwrittenOnRecursiveStructures) {
  auto [status, std_out, std_err] =
      Run("MySuite."
          "InitializesRecursiveProtoIfInfiniteRecursivePolicyIsOverwritten");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest,
       DefaultRepeatedFieldsMinSizeAppliesToAllRepeatedFields) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsIfRepeatedFieldsDontHaveTheMinimumSize");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest,
       DefaultRepeatedFieldsMaxSizeAppliesToAllRepeatedFields) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsIfRepeatedFieldsDontHaveTheMaximumSize");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, FailsWhenRepeatedFieldsSizeRangeIsInvalid) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsToInitializeIfRepeatedFieldsSizeRangeIsInvalid");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err, HasSubstr("size range is not valid"));
}

TEST_F(UnitTestModeTest, UsesPolicyProvidedDefaultDomainForProtos) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenSubprotosDontSetOptionalI32");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, ChecksTypeOfProvidedDefaultDomainForProtos) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenWrongDefaultProtobufDomainIsProvided");
  ExpectTargetAbort(status, std_err);
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("does not match the expected message type"));
}

TEST_F(UnitTestModeTest, PoliciesApplyToFieldsInOrder) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenI32FieldValuesDontRespectAllPolicies");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, AlwaysSetAndUnsetWorkOnOneofFields) {
  auto [status, std_out, std_err] =
      Run("MySuite.FailsWhenOneofFieldDoesntHaveOneofValue");
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

void ExpectStackLimitExceededMessage(absl::string_view std_err,
                                     size_t limit_bytes) {
#ifdef FUZZTEST_USE_CENTIPEDE
  EXPECT_THAT_LOG(std_err,
                  ContainsRegex(absl::StrCat("Stack limit exceeded: [0-9]+ > ",
                                             limit_bytes)));
#else
  EXPECT_THAT_LOG(std_err, HasSubstr(absl::StrCat("Configured limit is ",
                                                  limit_bytes, ".")));
#endif
}

TEST_F(UnitTestModeTest, StackLimitWorks) {
#if defined(__GNUC__) && !defined(__clang__)
  GTEST_SKIP() << "No coverage instrumentation for GCC yet: skipping tests.";
#endif
#if defined(__has_feature)
#if !__has_feature(coverage_sanitizer)
  GTEST_SKIP() << "No coverage instrumentation: skipping the stack limit test "
                  "in the unit test mode. Please run with --config=fuzztest to "
                  "enable these tests!";
#endif
#endif

  auto [status, std_out, std_err] =
      Run("MySuite.DataDependentStackOverflow", kDefaultTargetBinary,
          /*env=*/{}, /*fuzzer_flags=*/{{"stack_limit_kb", "1000"}});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  ExpectStackLimitExceededMessage(std_err, 1024000);
  ExpectTargetAbort(status, std_err);
}

TEST_F(UnitTestModeTest, RssLimitFlagWorks) {
  auto [status, std_out, std_err] =
      Run("MySuite.LargeHeapAllocation", kDefaultTargetBinary,
          /*env=*/{}, /*fuzzer_flags=*/{{"rss_limit_mb", "1024"}});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  EXPECT_THAT_LOG(std_err, ContainsRegex(absl::StrCat("RSS limit exceeded")));
  ExpectTargetAbort(status, std_err);
}

TEST_F(UnitTestModeTest, TimeLimitFlagWorks) {
  auto [status, std_out, std_err] =
      Run("MySuite.Sleep", kDefaultTargetBinary,
          /*env=*/{},
          /*fuzzer_flags=*/{{"time_limit_per_input", "1s"}});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  EXPECT_THAT_LOG(std_err, ContainsRegex("Per-input timeout exceeded"));
  ExpectTargetAbort(status, std_err);
}

TEST_F(UnitTestModeTest, TestIsSkippedWhenRequestedInFixturePerTest) {
  auto [status, std_out, std_err] =
      Run("SkippedTestFixturePerTest.SkippedTest", kDefaultTargetBinary,
          /*env=*/{},
          /*fuzzer_flags=*/{{"time_limit_per_input", "1s"}});
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("Skipping SkippedTestFixturePerTest.SkippedTest"));
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("SkippedTest is executed")));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, TestIsSkippedWhenRequestedInFixturePerIteration) {
  auto [status, std_out, std_err] =
      Run("SkippedTestFixturePerIteration.SkippedTest", kDefaultTargetBinary,
          /*env=*/{},
          /*fuzzer_flags=*/{{"time_limit_per_input", "1s"}});
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("SkippedTest is executed")));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(UnitTestModeTest, InputsAreSkippedWhenRequestedInTests) {
  auto [status, std_out, std_err] =
      Run("MySuite.SkipInputs", kDefaultTargetBinary,
          /*env=*/{},
          /*fuzzer_flags=*/{{"time_limit_per_input", "1s"}});
  EXPECT_THAT_LOG(std_err, HasSubstr("Skipped input"));
}

// Tests for the FuzzTest command line interface.
class GenericCommandLineInterfaceTest : public ::testing::Test {
 protected:
  RunResults RunWith(
      absl::flat_hash_map<std::string, std::string> flags,
      const absl::flat_hash_map<std::string, std::string>& env = {},
      absl::Duration timeout = absl::Minutes(10),
      absl::string_view binary = kDefaultTargetBinary,
      const absl::flat_hash_map<std::string, std::string>& non_fuzztest_flags =
          {}) {
    flags["print_subprocess_log"] = "true";
    return RunBinary(BinaryPath(binary),
                     RunOptions{/*flags=*/non_fuzztest_flags,
                                /*fuzztest_flags=*/flags,
                                /*raw_args=*/{},
                                /*env=*/WithTestSanitizerOptions(env),
                                /*timeout=*/timeout});
  }
};

TEST_F(GenericCommandLineInterfaceTest, FuzzTestsAreFoundInTheBinary) {
  auto [status, std_out, std_err] = RunWith({{"list_fuzz_tests", "true"}});
  EXPECT_THAT_LOG(std_out, HasSubstr("[*] Fuzz test: MySuite.Coverage"));
  EXPECT_THAT_LOG(std_out, HasSubstr("[*] Fuzz test: MySuite.DivByZero"));
  EXPECT_THAT_LOG(std_out,
                  HasSubstr("[*] Fuzz test: MySuite.PassesWithPositiveInput"));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(GenericCommandLineInterfaceTest,
       DynamicallyRegisteredFuzzTestsAreFound) {
  auto [status, std_out, std_err] =
      RunWith(/*flags=*/{{"list_fuzz_tests", "true"}}, /*env=*/{},
              /*timeout=*/absl::Minutes(1),
              /*binary=*/"testdata/dynamically_registered_fuzz_tests");
  EXPECT_THAT_LOG(std_out,
                  HasSubstr("[*] Fuzz test: TestSuiteOne.DoesNothing/1"));
  EXPECT_THAT_LOG(std_out,
                  HasSubstr("[*] Fuzz test: TestSuiteTwo.DoesNothing/2"));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

// Tests for the FuzzTest command line interface in fuzzing mode, which can only
// run with coverage instrumentation enabled.
class FuzzingModeCommandLineInterfaceTest
    : public GenericCommandLineInterfaceTest {
 protected:
  void SetUp() override {
    GenericCommandLineInterfaceTest::SetUp();
#if defined(__GNUC__) && !defined(__clang__)
    GTEST_SKIP() << "No coverage instrumentation for GNU compiler yet: "
                    "skipping tests in fuzzing mode.";
#endif
#if defined(__has_feature)
#if !__has_feature(coverage_sanitizer)
    GTEST_SKIP() << "No coverage instrumentation: skipping the fuzzing mode "
                    "command line interface tests. "
                    "Please run with --config=fuzztest or --config=centipede "
                    "to enable these tests!";
#endif
#endif
  }
};

TEST_F(FuzzingModeCommandLineInterfaceTest, WrongFuzzTestNameTriggersError) {
  auto [status, std_out, std_err] = RunWith({{"fuzz", "WrongName"}});
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("No FUZZ_TEST matches the name: WrongName"));
  EXPECT_THAT(status, Ne(ExitCode(0)));
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       MatchingMultipleFuzzTestsTriggersError) {
  auto [status, std_out, std_err] = RunWith({{"fuzz", "Bad"}});
  EXPECT_THAT_LOG(
      std_err,
      HasSubstr(
          "Multiple FUZZ_TESTs match the name: Bad\n\nPlease select one. "
          "Matching tests:\n MySuite.BadFilter\n MySuite.BadWithMinSize\n"));
  EXPECT_THAT(status, Ne(ExitCode(0)));
}

TEST_F(FuzzingModeCommandLineInterfaceTest, RunsAbortTestAndDetectsAbort) {
  auto [status, std_out, std_err] = RunWith({{"fuzz", "MySuite.Aborts"}});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  ExpectTargetAbort(status, std_err);
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       FuzzTestCanBeSelectedForFuzzingUsingSubstring) {
  auto [status, std_out, std_err] = RunWith({{"fuzz", "Abort"}});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  ExpectTargetAbort(status, std_err);
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       IgnoresNegativeFuzzingRunsLimitInEnvVar) {
  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.PassesWithPositiveInput"}},
              {{"FUZZTEST_MAX_FUZZING_RUNS", "-1"}},
              /*timeout=*/absl::Seconds(10));
  EXPECT_THAT_LOG(std_err, HasSubstr("will not limit fuzzing runs"));
}

TEST_F(FuzzingModeCommandLineInterfaceTest, LimitsFuzzingRunsWhenEnvVarIsSet) {
  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.PassesWithPositiveInput"}},
              {{"FUZZTEST_MAX_FUZZING_RUNS", "100"}});
#ifdef FUZZTEST_USE_CENTIPEDE
  EXPECT_THAT_LOG(std_err, HasSubstr("[S0.100] end-fuzz"));
#else
  EXPECT_THAT_LOG(std_err,
                  // 100 fuzzing runs + 1 seed run.
                  HasSubstr("Total runs: 101"));
#endif  // FUZZTEST_USE_CENTIPEDE
}

TEST_F(FuzzingModeCommandLineInterfaceTest, LimitsFuzzingRunsWhenTimeoutIsSet) {
  auto [status, std_out, std_err] = RunWith(
      {{"fuzz", "MySuite.PassesWithPositiveInput"}, {"fuzz_for", "1s"}});
  EXPECT_THAT_LOG(std_err, HasSubstr("Fuzzing timeout set to: 1s"));
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       ReproducerIsDumpedWhenReproducersOutDirEnvVarIsSet) {
  TempDir out_dir;

  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.StringFast"}},
              {{"FUZZTEST_REPRODUCERS_OUT_DIR", out_dir.path()}});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"Fuzz"));
  ExpectTargetAbort(status, std_err);

  auto replay_files = ReadFileOrDirectory(out_dir.path().c_str());
  ASSERT_EQ(replay_files.size(), 1) << std_err;
  auto parsed = IRObject::FromString(replay_files[0].data);
  ASSERT_TRUE(parsed) << std_err;
  auto args = parsed->ToCorpus<std::tuple<std::string>>();
  EXPECT_THAT(args, Optional(FieldsAre(StartsWith("Fuzz")))) << std_err;
  EXPECT_THAT_LOG(std_err,
                  AllOf(HasSubstr("Reproducer file was dumped at:"),
                        HasSubstr(replay_files[0].path),
                        HasSubstr(absl::StrCat("--test_env=FUZZTEST_REPLAY=",
                                               replay_files[0].path))));
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       ReproducerIsDumpedWhenUndeclaredOutputsEnvVarIsSet) {
  TempDir out_dir;

  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.StringFast"}},
              {{"TEST_UNDECLARED_OUTPUTS_DIR", out_dir.path()}});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"Fuzz"));
  ExpectTargetAbort(status, std_err);

  auto replay_files = ReadFileOrDirectory(out_dir.path().c_str());
  ASSERT_EQ(replay_files.size(), 1) << std_err;
  auto parsed = IRObject::FromString(replay_files[0].data);
  ASSERT_TRUE(parsed) << std_err;
  auto args = parsed->ToCorpus<std::tuple<std::string>>();
  EXPECT_THAT(args, Optional(FieldsAre(StartsWith("Fuzz")))) << std_err;
  EXPECT_THAT_LOG(
      std_err,
      AllOf(HasSubstr("Reproducer file was dumped under "
                      "TEST_UNDECLARED_OUTPUTS_DIR"
                      ),
            HasSubstr(replay_files[0].path),
            HasSubstr(
                absl::StrCat("--test_env=FUZZTEST_REPLAY=/tmp/fuzztest_repro/",
                             Basename(replay_files[0].path)))));
}

TEST_F(FuzzingModeCommandLineInterfaceTest, SavesCorpusWhenEnvVarIsSet) {
  TempDir out_dir;
  // We cannot use a non-crashing test since there is no easy way to limit the
  // run time here.
  //
  // Although theoretically possible, it is extreme unlikely that the test would
  // find the crash without saving some corpus.
  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.String"}},
              {{"FUZZTEST_TESTSUITE_OUT_DIR", out_dir.path()}});

  auto corpus_files = ReadFileOrDirectory(out_dir.path().c_str());
  EXPECT_THAT(corpus_files, Not(IsEmpty())) << std_err;
}

void ExpectCorpusInputMessageInLogs(absl::string_view logs, int num_inputs) {
#ifdef FUZZTEST_USE_CENTIPEDE
  EXPECT_THAT(logs,
              HasSubstr(absl::StrFormat("%d inputs to rerun", num_inputs)))
      << logs;
#else
  EXPECT_THAT(logs,
              HasSubstr(absl::StrFormat(
                  "In total, loaded %d inputs and ignored 0 invalid inputs",
                  num_inputs)))
      << logs;
#endif
}

void ExpectMinimizationOutputMessageInLogs(absl::string_view logs,
                                           int num_outputs,
                                           int num_allowed_dups = 0) {
  std::vector<testing::Matcher<std::string>> matchers;
  for (int i = 0; i <= num_allowed_dups; ++i) {
#ifdef FUZZTEST_USE_CENTIPEDE
    matchers.push_back(
        HasSubstr(absl::StrFormat("distilled: %d", num_outputs + i)));
#else
    matchers.push_back(HasSubstr(absl::StrFormat(
        "Selected %d corpus inputs in minimization mode", num_outputs + i)));
#endif
  }
  EXPECT_THAT(logs, AnyOfArray(matchers)) << logs;
}

TEST_F(FuzzingModeCommandLineInterfaceTest, RestoresCorpusWhenEnvVarIsSet) {
  TempDir corpus_dir;
  // Although theoretically possible, it is extreme unlikely that the test would
  // find the crash without saving some corpus.
  auto [producer_status, producer_std_out, producer_std_err] =
      RunWith({{"fuzz", "MySuite.String"}, {"fuzz_for", "10s"}},
              {{"FUZZTEST_TESTSUITE_OUT_DIR", corpus_dir.path()}});

  auto corpus_files = ReadFileOrDirectory(corpus_dir.path().c_str());
  ASSERT_THAT(corpus_files, Not(IsEmpty())) << producer_std_err;

  auto [consumer_status, consumer_std_out, consumer_std_err] =
      RunWith({{"fuzz", "MySuite.String"}},
              {{"FUZZTEST_TESTSUITE_IN_DIR", corpus_dir.path()},
               {"FUZZTEST_MAX_FUZZING_RUNS", "0"}});
  ExpectCorpusInputMessageInLogs(consumer_std_err, corpus_files.size());
}

TEST_F(FuzzingModeCommandLineInterfaceTest, MinimizesCorpusWhenEnvVarIsSet) {
  TempDir corpus_dir;
  TempDir minimized_corpus_dir;
  // Although theoretically possible, it is extreme unlikely that the test would
  // find the crash without saving some corpus.
  auto [producer_status, producer_std_out, producer_std_err] =
      RunWith({{"fuzz", "MySuite.String"}, {"fuzz_for", "10s"}},
              {{"FUZZTEST_TESTSUITE_OUT_DIR", corpus_dir.path()}});

  auto corpus_files = ReadFileOrDirectory(corpus_dir.path().c_str());
  ASSERT_THAT(corpus_files, Not(IsEmpty())) << producer_std_err;
  std::vector<std::string> corpus_data;
  for (const FilePathAndData& corpus_file : corpus_files) {
    corpus_data.push_back(corpus_file.data);
  }

  auto [minimizer_status, minimizer_std_out, minimizer_std_err] =
      RunWith({{"fuzz", "MySuite.String"}},
              {{"FUZZTEST_MINIMIZE_TESTSUITE_DIR", corpus_dir.path()},
               {"FUZZTEST_TESTSUITE_OUT_DIR", minimized_corpus_dir.path()}});

  auto minimized_corpus_files =
      ReadFileOrDirectory(minimized_corpus_dir.path().c_str());
  EXPECT_THAT(minimized_corpus_files,
              AllOf(Not(IsEmpty()), SizeIs(Le(corpus_files.size()))))
      << minimizer_std_err;
  std::vector<std::string> minimized_corpus_data;
  for (const FilePathAndData& minimized_corpus_file : minimized_corpus_files) {
    minimized_corpus_data.push_back(minimized_corpus_file.data);
  }
  EXPECT_THAT(minimized_corpus_data, IsSubsetOf(corpus_data));

  ExpectCorpusInputMessageInLogs(minimizer_std_err, corpus_files.size());
  ExpectMinimizationOutputMessageInLogs(minimizer_std_err,
                                        minimized_corpus_files.size());
}

TEST_F(FuzzingModeCommandLineInterfaceTest, MinimizesDuplicatedCorpus) {
  TempDir corpus_dir;
  TempDir minimized_corpus_dir;
  // We cannot use a non-crashing test since there is no easy way to limit the
  // run time here.
  //
  // Although theoretically possible, it is extreme unlikely that the test would
  // find the crash without saving some corpus.
  auto [producer_status, producer_std_out, producer_std_err] =
      RunWith({{"fuzz", "MySuite.String"}, {"fuzz_for", "10s"}},
              {{"FUZZTEST_TESTSUITE_OUT_DIR", corpus_dir.path()}});

  auto corpus_files = ReadFileOrDirectory(corpus_dir.path().c_str());
  ASSERT_THAT(corpus_files, Not(IsEmpty())) << producer_std_err;
  for (const auto& corpus_file : corpus_files) {
    ASSERT_TRUE(WriteFile(corpus_file.path + "_dup", corpus_file.data));
  }

  auto [minimizer_status, minimizer_std_out, minimizer_std_err] =
      RunWith({{"fuzz", "MySuite.String"}},
              {{"FUZZTEST_MINIMIZE_TESTSUITE_DIR", corpus_dir.path()},
               {"FUZZTEST_TESTSUITE_OUT_DIR", minimized_corpus_dir.path()}});

  auto minimized_corpus_files =
      ReadFileOrDirectory(minimized_corpus_dir.path().c_str());
  EXPECT_THAT(minimized_corpus_files,
              AllOf(Not(IsEmpty()), SizeIs(Le(corpus_files.size()))))
      << minimizer_std_err;

  ExpectCorpusInputMessageInLogs(minimizer_std_err, corpus_files.size() * 2);
  // TODO(b/207375007): Due to non-determinism, sometimes duplicated
  // input can reach new coverage and thus be counted into the corpus
  // (but not reflected in the files since they are
  // content-addressed). We use `num_allowed_dups` to mitigate the flakiness.
  ExpectMinimizationOutputMessageInLogs(
      minimizer_std_err, minimized_corpus_files.size(), /*num_allowed_dups=*/2);
}

class ReplayFile {
 public:
  template <typename T>
  ReplayFile(std::in_place_t, const T& corpus) {
    filename_ = dir_.path() / "replay_file";
    WriteFile(filename_, internal::IRObject::FromCorpus(corpus).ToString());
  }

  auto GetReplayEnv() const {
    return absl::flat_hash_map<std::string, std::string>{
        {"FUZZTEST_REPLAY", filename_}};
  }

  auto GetMinimizeEnv() const {
    return absl::flat_hash_map<std::string, std::string>{
        {"FUZZTEST_MINIMIZE_REPRODUCER", filename_}};
  }

 private:
  TempDir dir_;
  std::string filename_;
};

TEST_F(FuzzingModeCommandLineInterfaceTest,
       ReplayingNonCrashingReproducerDoesNotCrash) {
  ReplayFile replay(std::in_place, std::tuple<std::string>{"NotFuzz"});

  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.String"}}, replay.GetReplayEnv());
  EXPECT_THAT(status, Eq(ExitCode(0))) << std_err;
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       ReplayingCrashingReproducerCrashes) {
  ReplayFile replay(std::in_place,
                    std::tuple<std::string>{"Fuzz with some tail."});

  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.String"}}, replay.GetReplayEnv());
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"Fuzz with some tail.\""));
  EXPECT_THAT(status, Eq(Signal(SIGABRT)));
}

// The TypeErased tests below try the same as above, but with Domain<T> domains
// to makes sure the type erasure of the corpus_type can be correctly
// serialized.
TEST_F(FuzzingModeCommandLineInterfaceTest,
       ReproducerIsDumpedWhenEnvVarIsSetTypeErased) {
  TempDir out_dir;

  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.WithDomainClass"}},
              {{"FUZZTEST_REPRODUCERS_OUT_DIR", out_dir.path()}});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: 10"));
  EXPECT_THAT(status, Ne(ExitCode(0))) << std_err;

  auto replay_files = ReadFileOrDirectory(out_dir.path().c_str());
  ASSERT_EQ(replay_files.size(), 1) << std_err;
  auto parsed = IRObject::FromString(replay_files[0].data);
  ASSERT_TRUE(parsed) << std_err;
  auto args = parsed->ToCorpus<std::tuple<uint8_t, double>>();
  EXPECT_THAT(args, Optional(FieldsAre(10, _))) << std_err;
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       ReplayingNonCrashingReproducerDoesNotCrashTypeErased) {
  ReplayFile replay(std::in_place, std::tuple<uint8_t, double>{11, 11});

  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.WithDomainClass"}}, replay.GetReplayEnv());
  EXPECT_THAT(status, Eq(ExitCode(0))) << std_err;
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       ReplayingCrashingReproducerCrashesTypeErased) {
  ReplayFile replay(std::in_place, std::tuple<uint8_t, double>{10, 1979.125});
  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.WithDomainClass"}}, replay.GetReplayEnv());
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: 10"));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 1: 1979.125"));
  EXPECT_THAT(status, Ne(ExitCode(0)));
}

TEST_F(FuzzingModeCommandLineInterfaceTest, MinimizerFindsSmallerInput) {
  std::string current_input = "ABCXDEF";
  while (current_input != "X") {
    TempDir out_dir;
    ReplayFile replay(std::in_place, std::tuple<std::string>{current_input});
    auto env = replay.GetMinimizeEnv();
    env["FUZZTEST_REPRODUCERS_OUT_DIR"] = out_dir.path();

    auto [status, std_out, std_err] =
        RunWith({{"fuzz", "MySuite.Minimizer"}}, env);
    ASSERT_THAT_LOG(std_err, HasSubstr("argument 0: \""));
    ASSERT_THAT(status, Eq(Signal(SIGABRT)));

    auto replay_files = ReadFileOrDirectory(out_dir.path().c_str());
    ASSERT_EQ(replay_files.size(), 1) << std_err;
    auto parsed = IRObject::FromString(replay_files[0].data);
    ASSERT_TRUE(parsed) << std_err;
    auto args = parsed->ToCorpus<std::tuple<std::string>>();
    ASSERT_THAT(args, Optional(FieldsAre(HasSubstr("X"))));
    std::string escaped;
    StringPrinter{}.PrintUserValue(std::get<0>(*args), &escaped,
                                   PrintMode::kHumanReadable);
    fprintf(stderr, "Found smaller case <%s>\n", escaped.c_str());
    current_input = std::get<0>(*args);
  }
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       FuzzerStatsArePrintedOnTermination) {
#ifdef FUZZTEST_USE_CENTIPEDE
  GTEST_SKIP() << "Skip fuzzer stats test when running with Centipede because "
                  "stats are not printed.";
#endif
  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.PassesWithPositiveInput"}},
              /*env=*/{},
              /*timeout=*/absl::Seconds(10));
  EXPECT_THAT_LOG(std_err, HasSubstr("Fuzzing was terminated"));
  EXPECT_THAT_LOG(std_err, HasSubstr("=== Fuzzing stats"));
  EXPECT_THAT_LOG(std_err, HasSubstr("Total runs:"));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(FuzzingModeCommandLineInterfaceTest, SilenceTargetWorking) {
  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.TargetPrintSomethingThenAbrt"}},
              /*env=*/{{"FUZZTEST_SILENCE_TARGET", "1"}});
  EXPECT_THAT_LOG(std_out, Not(HasSubstr("Hello World from target stdout")));
  EXPECT_THAT_LOG(std_err, HasSubstr("=== Fuzzing stats"));
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("Hello World from target stderr")));
  ExpectTargetAbort(status, std_err);
}

TEST_F(FuzzingModeCommandLineInterfaceTest, NonFatalFailureAllowsMinimization) {
#ifdef FUZZTEST_USE_CENTIPEDE
  GTEST_SKIP()
      << "Skipping tests for non-fatal failure minimization when running with "
         "Centipede. Please run with --config=fuzztest to enable these tests!";
#endif
  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.NonFatalFailureAllowsMinimization"}});
  // The final failure should be with the known minimal result, even though many
  // "larger" inputs also trigger the failure.
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"0123\""));

  ExpectTargetAbort(status, std_err);
}

TEST_F(FuzzingModeCommandLineInterfaceTest, GoogleTestHasCurrentTestInfo) {
  auto [status, std_out, std_err] = RunWith(
      {{"fuzz", "MySuite.GoogleTestHasCurrentTestInfo"}, {"fuzz_for", "1s"}});
  EXPECT_THAT_LOG(
      std_out, HasSubstr("[       OK ] MySuite.GoogleTestHasCurrentTestInfo"));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(FuzzingModeCommandLineInterfaceTest, ConfiguresStackLimitByFlag) {
  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.DataDependentStackOverflow"},
               {"stack_limit_kb", "1000"}});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  ExpectStackLimitExceededMessage(std_err, 1024000);
  ExpectTargetAbort(status, std_err);
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       DoesNotPrintWarningForDisabledLimitFlagsByDefault) {
  auto [status, std_out, std_err] = RunWith(
      {{"fuzz", "MySuite.PassesWithPositiveInput"}, {"fuzz_for", "10s"}},
      /*env=*/{},
      /*timeout=*/absl::Seconds(20));
  EXPECT_THAT_LOG(std_err,
                  Not(HasSubstr("limit is specified but will be ignored")));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(FuzzingModeCommandLineInterfaceTest, RssLimitFlagWorks) {
  auto [status, std_out, std_err] = RunWith(
      {{"fuzz", "MySuite.LargeHeapAllocation"}, {"rss_limit_mb", "1024"}},
      /*env=*/{}, /*timeout=*/absl::Seconds(10));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  EXPECT_THAT_LOG(std_err, ContainsRegex(absl::StrCat("RSS limit exceeded")));
  ExpectTargetAbort(status, std_err);
}

TEST_F(FuzzingModeCommandLineInterfaceTest, TimeLimitFlagWorks) {
  auto [status, std_out, std_err] =
      RunWith({{"fuzz", "MySuite.Sleep"}, {"time_limit_per_input", "1s"}},
              /*env=*/{});
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  EXPECT_THAT_LOG(std_err, ContainsRegex("Per-input timeout exceeded"));
  ExpectTargetAbort(status, std_err);
}

// TODO: b/340232436 - Once fixed, remove this test since we will no longer need
// to restrict the filter to only fuzz tests.
TEST_F(FuzzingModeCommandLineInterfaceTest, RunsOnlyFuzzTests) {
  auto [status, std_out, std_err] =
      RunWith({{"fuzz_for", "1s"}}, /*env=*/{}, /*timeout=*/absl::Seconds(10),
              "testdata/unit_test_and_fuzz_tests");

  EXPECT_THAT_LOG(std_out,
                  Not(HasSubstr("[ RUN      ] UnitTest.AlwaysPasses")));
  EXPECT_THAT_LOG(std_out, HasSubstr("[ RUN      ] FuzzTest.AlwaysPasses"));
  EXPECT_THAT_LOG(std_out, HasSubstr("[ RUN      ] FuzzTest.AlsoAlwaysPasses"));
  EXPECT_THAT_LOG(std_out, HasSubstr("2 tests from 1 test suite ran."));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       AllowsSpecifyingFilterWithFuzzForDuration) {
  auto [status, std_out, std_err] =
      RunWith({{"fuzz_for", "1s"}}, /*env=*/{}, /*timeout=*/absl::Seconds(10),
              "testdata/unit_test_and_fuzz_tests",
              {{GTEST_FLAG_PREFIX_ "filter",
                "UnitTest.AlwaysPasses:FuzzTest.AlwaysPasses"}});

  EXPECT_THAT_LOG(std_out, HasSubstr("[ RUN      ] FuzzTest.AlwaysPasses"));
  EXPECT_THAT_LOG(std_out,
                  Not(HasSubstr("[ RUN      ] FuzzTest.AlsoAlwaysPasses")));
  EXPECT_THAT_LOG(std_out,
                  Not(HasSubstr("[ RUN      ] UnitTest.AlwaysPasses")));
  EXPECT_THAT_LOG(std_out, HasSubstr("1 test from 1 test suite ran."));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

// This tests both the command line interface and the fuzzing logic. It is under
// FuzzingModeCommandLineInterfaceTest so it can specify the command line.
TEST_F(FuzzingModeCommandLineInterfaceTest, CorpusDoesNotContainSkippedInputs) {
  TempDir corpus_dir;
  // Although theoretically possible, it is extreme unlikely that the test would
  // find the crash without saving some corpus.
  auto [producer_status, producer_std_out, producer_std_err] =
      RunWith({{"fuzz", "MySuite.SkipInputs"}, {"fuzz_for", "10s"}},
              {{"FUZZTEST_TESTSUITE_OUT_DIR", corpus_dir.path()}});

  ASSERT_THAT_LOG(producer_std_err, HasSubstr("Skipped input"));

  auto [replayer_status, replayer_std_out, replayer_std_err] =
      RunWith({{"fuzz", "MySuite.SkipInputs"}},
              {{"FUZZTEST_REPLAY", corpus_dir.path()}});

  EXPECT_THAT(replayer_std_err, Not(HasSubstr("Skipped input")));
}

TEST_F(FuzzingModeCommandLineInterfaceTest, UsesCentipedeBinaryWhenEnvIsSet) {
#ifndef FUZZTEST_USE_CENTIPEDE
  GTEST_SKIP() << "Skipping Centipede-specific test";
#endif
  TempDir temp_dir;
  auto [status, std_out, std_err] = RunWith(
      {
          {"fuzz_for", "1s"},
          {"corpus_database", temp_dir.path()},
      },
      {{"FUZZTEST_CENTIPEDE_BINARY", CentipedePath()}},
      /*timeout=*/absl::Minutes(1), "testdata/unit_test_and_fuzz_tests");
  EXPECT_THAT_LOG(
      std_err,
      HasSubstr("Starting the update of the corpus database for fuzz tests"));
  EXPECT_THAT_LOG(std_err, HasSubstr("FuzzTest.AlwaysPasses"));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_F(FuzzingModeCommandLineInterfaceTest,
       UsesCentipedeBinaryWhenCentipedeBinaryPathFlagIsSet) {
#ifndef FUZZTEST_USE_CENTIPEDE
  GTEST_SKIP() << "Skipping Centipede-specific test";
#endif
  TempDir temp_dir;
  auto [status, std_out, std_err] = RunWith(
      {
          {"fuzz_for", "1s"},
          {"corpus_database", temp_dir.path()},
          {"internal_centipede_command", ShellEscape(CentipedePath())},
      },
      /*env=*/{},
      /*timeout=*/absl::Minutes(1), "testdata/unit_test_and_fuzz_tests");
  EXPECT_THAT_LOG(std_err, HasSubstr("Running Centipede command"));
  EXPECT_THAT_LOG(std_err, HasSubstr("FuzzTest.AlwaysPasses"));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

enum class ExecutionModelParam {
  kTestBinary,
  kTestBinaryInvokingCentipedeBinary,
  kCentipedeBinary,
};

std::vector<ExecutionModelParam> GetAvailableExecutionModels() {
  std::vector<ExecutionModelParam> results = {ExecutionModelParam::kTestBinary};
#ifdef FUZZTEST_USE_CENTIPEDE
  results.push_back(ExecutionModelParam::kTestBinaryInvokingCentipedeBinary);
  results.push_back(ExecutionModelParam::kCentipedeBinary);
#endif
  return results;
}

// Tests for the fixture logic in fuzzing mode, which can only run
// with coverage instrumentation enabled.
class FuzzingModeFixtureTest
    : public ::testing::TestWithParam<ExecutionModelParam> {
 protected:
  void SetUp() override {
#if defined(__GNUC__) && !defined(__clang__)
    GTEST_SKIP() << "No coverage instrumentation for GNU compiler yet: "
                    "skipping tests in fuzzing mode.";
#endif
#if defined(__has_feature)
#if !__has_feature(coverage_sanitizer)
    GTEST_SKIP() << "No coverage instrumentation: skipping the fuzzing mode "
                    "fixture tests. "
                    "Please run with --config=fuzztest or --config=centipede "
                    "to enable these tests!";
#endif
#endif
  }

  RunResults Run(absl::string_view test_name, int iterations) {
    switch (GetParam()) {
      case ExecutionModelParam::kTestBinary: {
        RunOptions run_options;
        run_options.fuzztest_flags = {{"fuzz", std::string(test_name)},
                                      {"print_subprocess_log", "true"}};
        run_options.env = {
            {"FUZZTEST_MAX_FUZZING_RUNS", absl::StrCat(iterations)}};
        run_options.timeout = absl::InfiniteDuration();
        return RunBinary(BinaryPath(kDefaultTargetBinary), run_options);
      }
      case ExecutionModelParam::kTestBinaryInvokingCentipedeBinary: {
        RunOptions run_options;
        run_options.fuzztest_flags = {
            {"fuzz", std::string(test_name)},
            {"print_subprocess_log", "true"},
            {"internal_centipede_command", ShellEscape(CentipedePath())}};
        run_options.env = {
            {"FUZZTEST_MAX_FUZZING_RUNS", absl::StrCat(iterations)}};
        run_options.timeout = absl::InfiniteDuration();
        return RunBinary(BinaryPath(kDefaultTargetBinary), run_options);
      }
      case ExecutionModelParam::kCentipedeBinary: {
        TempDir workdir;
        RunOptions run_options;
        run_options.flags = {
            {"print_runner_log", "true"},
            {"exit_on_crash", "true"},
            {"workdir", workdir.path()},
            {"binary", absl::StrCat(BinaryPath(kDefaultTargetBinary), " ",
                                    CreateFuzzTestFlag("fuzz", test_name))},
            {"num_runs", absl::StrCat(iterations)}};
        run_options.timeout = absl::InfiniteDuration();
        return RunBinary(CentipedePath(), run_options);
      }
    }
    FUZZTEST_LOG(FATAL) << "Unsupported execution model!\n";
  }
};

TEST_P(FuzzingModeFixtureTest, GlobalEnvironmentIsSetUpForFailingTest) {
  auto [status, std_out, std_err] =
      Run("MySuite.GoogleTestExpect", /*iterations=*/10);
  EXPECT_GT(CountTargetRuns(std_err), 0);
  EXPECT_EQ(
      CountTargetRuns(std_err),
      CountSubstrs(std_err, "<<GlobalEnvironment::GlobalEnvironment()>>"));
  EXPECT_EQ(CountTargetRuns(std_err),
            CountSubstrs(std_err, "<<GlobalEnvironment::SetUp()>>"));
}

TEST_P(FuzzingModeFixtureTest,
       GlobalEnvironmentGoesThroughCompleteLifecycleForSuccessfulTest) {
  auto [status, std_out, std_err] =
      Run("MySuite.GoogleTestNeverFails", /*iterations=*/10);
  EXPECT_GT(CountTargetRuns(std_err), 0);
  EXPECT_EQ(
      CountTargetRuns(std_err),
      CountSubstrs(std_err, "<<GlobalEnvironment::GlobalEnvironment()>>"));
  EXPECT_EQ(CountTargetRuns(std_err),
            CountSubstrs(std_err, "<<GlobalEnvironment::SetUp()>>"));
  EXPECT_EQ(CountTargetRuns(std_err),
            CountSubstrs(std_err, "<<GlobalEnvironment::TearDown()>>"));
  EXPECT_EQ(
      CountTargetRuns(std_err),
      CountSubstrs(std_err, "<<GlobalEnvironment::~GlobalEnvironment()>>"));
}

TEST_P(FuzzingModeFixtureTest, FixtureGoesThroughCompleteLifecycle) {
  auto [status, std_out, std_err] = Run("FixtureTest.NeverFails",
                                        /*iterations=*/10);
#ifdef FUZZTEST_USE_CENTIPEDE
  // In the single binary execution model there is a target process running in
  // controller mode, where no FuzzTest fixture object is created.
  const int target_controller_runs =
      GetParam() == ExecutionModelParam::kTestBinary ||
      GetParam() == ExecutionModelParam::kTestBinaryInvokingCentipedeBinary;
#else
  const int target_controller_runs = 0;
#endif
  EXPECT_GT(CountTargetRuns(std_err) - target_controller_runs, 0);
  EXPECT_EQ(CountTargetRuns(std_err) - target_controller_runs,
            CountSubstrs(std_err, "<<FixtureTest::FixtureTest()>>"));
  EXPECT_EQ(CountTargetRuns(std_err) - target_controller_runs,
            CountSubstrs(std_err, "<<FixtureTest::~FixtureTest()>>"));
}

TEST_P(FuzzingModeFixtureTest,
       GoogleTestPerIterationFixtureInstantiatedOncePerIteration) {
  auto [status, std_out, std_err] =
      Run("CallCountPerIteration."
          "CallCountIsAlwaysIncrementedFromInitialValue",
          /*iterations=*/10);
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_P(FuzzingModeFixtureTest,
       GoogleTestPerFuzzTestFixtureInstantiatedOncePerFuzzTest) {
  auto [status, std_out, std_err] =
      Run("CallCountPerFuzzTest.CallCountPerFuzzTestEqualsToGlobalCount",
          /*iterations=*/10);
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_P(FuzzingModeFixtureTest, GoogleTestStaticTestSuiteFunctionsCalledOnce) {
  auto [status, std_out, std_err] =
      Run("CountPerFuzzTest.CallCountPerFuzzTestEqualsToGlobalCount",
          /*iterations=*/10);
  EXPECT_GT(CountTargetRuns(std_err), 0);
  EXPECT_EQ(CountTargetRuns(std_err),
            CountSubstrs(std_err, "<<CallCountGoogleTest::SetUpTestSuite()>>"));
  EXPECT_EQ(
      CountTargetRuns(std_err),
      CountSubstrs(std_err, "<<CallCountGoogleTest::TearDownTestSuite()>>"));
}

TEST_P(FuzzingModeFixtureTest, TestIsSkippedWhenRequestedInFixturePerTest) {
  auto [status, std_out, std_err] =
      Run("SkippedTestFixturePerTest.SkippedTest", /*iterations=*/10);
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("Skipping SkippedTestFixturePerTest.SkippedTest"));
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("SkippedTest should not be run")));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_P(FuzzingModeFixtureTest,
       TestIsSkippedWhenRequestedInFixturePerIteration) {
  auto [status, std_out, std_err] =
      Run("SkippedTestFixturePerIteration.SkippedTest", /*iterations=*/10);
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("SkippedTest should not be run")));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

INSTANTIATE_TEST_SUITE_P(FuzzingModeFixtureTestWithExecutionModel,
                         FuzzingModeFixtureTest,
                         testing::ValuesIn(GetAvailableExecutionModels()));

// Tests for the crash finding ability of the fuzzing mode, which can
// only run with coverage instrumentation enabled.
class FuzzingModeCrashFindingTest
    : public ::testing::TestWithParam<ExecutionModelParam> {
 protected:
  void SetUp() override {
#if defined(__GNUC__) && !defined(__clang__)
    GTEST_SKIP() << "No coverage instrumentation for GNU compiler yet: "
                    "skipping tests in fuzzing mode.";
#endif
#if defined(__has_feature)
#if !__has_feature(coverage_sanitizer)
    GTEST_SKIP() << "No coverage instrumentation: skipping the fuzzing mode "
                    "crash finding tests. "
                    "Please run with --config=fuzztest or --config=centipede "
                    "to enable these tests!";
#endif
#endif
  }

  RunResults Run(absl::string_view test_name,
                 absl::string_view target_binary = kDefaultTargetBinary,
                 absl::flat_hash_map<std::string, std::string> env = {},
                 absl::Duration timeout = absl::InfiniteDuration()) {
    // We start the test binaries with `env` passed by the caller, but without
    // propagating env vars set by Bazel, such as TEST_SHARD_INDEX,
    // TEST_TOTAL_SHARDS, TEST_PREMATURE_EXIT_FILE, TEST_WARNINGS_OUTPUT_FILE,
    // etc. (See
    // https://bazel.build/reference/test-encyclopedia#initial-conditions.)
    // There are however env vars that we do want to propagate, which
    // we now need to do explicitly.
    env = WithTestSanitizerOptions(std::move(env));
    if (GetParam() == ExecutionModelParam::kCentipedeBinary) {
      TempDir workdir;
      RunOptions run_options;
      run_options.flags = {
          {"exit_on_crash", "true"},
          {"timeout_per_input", "0"},
          {"stop_at", absl::StrCat(absl::Now() + timeout)},
          {"workdir", workdir.path()},
          {"binary", absl::StrCat(BinaryPath(target_binary), " ",
                                  CreateFuzzTestFlag("fuzz", test_name))}};
      run_options.env = std::move(env);
      run_options.timeout = timeout + absl::Seconds(10);
      return RunBinary(CentipedePath(), run_options);
    }
    RunOptions run_options;
    run_options.fuzztest_flags = {{"fuzz", std::string(test_name)},
                                  {"fuzz_for", absl::StrCat(timeout)}};
    run_options.env = std::move(env);
    run_options.timeout = timeout + absl::Seconds(10);
    if (GetParam() == ExecutionModelParam::kTestBinaryInvokingCentipedeBinary) {
      run_options.fuzztest_flags["internal_centipede_command"] =
          ShellEscape(CentipedePath());
    }
    return RunBinary(BinaryPath(target_binary), run_options);
  }
};

TEST_P(FuzzingModeCrashFindingTest,
       BufferOverflowIsDetectedWithStringViewInFuzzingMode) {
#ifndef ADDRESS_SANITIZER
  GTEST_SKIP() << "Skipping crash finding test for ASAN errors without ASAN";
#endif
  auto [status, std_out, std_err] = Run("MySuite.BufferOverreadWithStringView");
  EXPECT_THAT_LOG(
      std_err,
      AnyOf(HasSubstr("ERROR: AddressSanitizer: container-overflow"),
            HasSubstr("ERROR: AddressSanitizer: heap-buffer-overflow")));
  EXPECT_THAT(status, Ne(ExitCode(0)));
}

TEST_P(FuzzingModeCrashFindingTest,
       UninitializedReadIsDetectedWithStringInFuzzingMode) {
#ifndef MEMORY_SANITIZER
  GTEST_SKIP() << "Skipping crash finding test for MSAN errors without MSAN";
#endif
  auto [status, std_out, std_err] = Run("MySuite.UninitializedReadWithString");
  EXPECT_THAT_LOG(
      std_err,
      AllOf(HasSubstr("MemorySanitizer: use-of-uninitialized-value"),
            Not(HasSubstr(
                "MemorySanitizer: nested bug in the same thread, aborting."))));
  EXPECT_THAT(status, Ne(ExitCode(0)));
}

TEST_P(FuzzingModeCrashFindingTest,
       DereferencingEmptyOptionalTriggersLibcppAssertionsWhenEnabled) {
#if defined(_LIBCPP_VERSION) && defined(_LIBCPP_ENABLE_ASSERTIONS)
  auto [status, std_out, std_err] = Run("MySuite.DereferenceEmptyOptional");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: std::nullopt"));
  ExpectTargetAbort(status, std_err);
#endif
}

TEST_P(FuzzingModeCrashFindingTest,
       BufferOverflowIsDetectedWithStringInFuzzingMode) {
#ifndef ADDRESS_SANITIZER
  GTEST_SKIP() << "Skipping crash finding test for ASAN errors without ASAN";
#endif
  auto [status, std_out, std_err] = Run("MySuite.BufferOverreadWithString");
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("ERROR: AddressSanitizer: heap-buffer-overflow"));
  EXPECT_THAT(status, Ne(ExitCode(0)));
}

TEST_P(FuzzingModeCrashFindingTest,
       BufferOverflowIsDetectedWithStringAndLvalueStringViewRef) {
#ifndef ADDRESS_SANITIZER
  GTEST_SKIP() << "Skipping crash finding test for ASAN errors without ASAN";
#endif
  auto [status, std_out, std_err] =
      Run("MySuite.BufferOverreadWithStringAndLvalueStringViewRef");
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("ERROR: AddressSanitizer: heap-buffer-overflow"));
  EXPECT_THAT(status, Ne(ExitCode(0)));
}

TEST_P(FuzzingModeCrashFindingTest,
       BufferOverflowIsDetectedWithStringAndRvalueStringViewRef) {
#ifndef ADDRESS_SANITIZER
  GTEST_SKIP() << "Skipping crash finding test for ASAN errors without ASAN";
#endif
  auto [status, std_out, std_err] =
      Run("MySuite.BufferOverreadWithStringAndRvalueStringViewRef");
  EXPECT_THAT_LOG(std_err,
                  HasSubstr("ERROR: AddressSanitizer: heap-buffer-overflow"));
  EXPECT_THAT(status, Ne(ExitCode(0)));
}

TEST_P(FuzzingModeCrashFindingTest, DivByZeroTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.DivByZero");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 1: 0"));
#if defined(ADDRESS_SANITIZER) || defined(MEMORY_SANITIZER)
  EXPECT_THAT(status, Ne(ExitCode(0))) << std_err;
#else
  EXPECT_THAT(status, Eq(Signal(SIGFPE))) << std_err;
#endif
}

TEST_P(FuzzingModeCrashFindingTest, Int32ValueTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.Int32ValueTest");
  // -559038737 is 0xdeadbeef in int32_t.
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: -559038737"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, CoverageTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.Coverage");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: 'F'"));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 1: 'u'"));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 2: 'z'"));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 3: 'z'"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, StringTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.String");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"Fuzz"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest,
       StringAsciiOnlyTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.StringAsciiOnly");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"Fuzz"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, StringRegexpTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.StringRegexp");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"Fuzz"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, StringViewTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.StringView");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"Fuzz"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, StrCmpTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.StrCmp");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"Hello!"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, BitFlagsFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.BitFlags");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: 21"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, EnumTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.EnumValue");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: Color{0}"));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 1: Color{1}"));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 2: Color{2}"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, EnumClassTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.EnumClassValue");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: ColorClass{0}"));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 1: ColorClass{1}"));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 2: ColorClass{2}"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, ProtoTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.Proto");
  EXPECT_THAT_LOG(std_err,
                  ContainsRegex(R"(argument 0: \((.*\n.*)?b:\s+true)"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, BitvectorValueTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.BitvectorValue");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: {true"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, VectorValueTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.VectorValue");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: {'F'"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, BitGenRefTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.BitGenRef");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: absl::BitGenRef{}"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest,
       FixedSizeVectorValueTestFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] = Run("MySuite.FixedSizeVectorValue");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: {'F'"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, GoogleTestExpectationsStopTheFuzzer) {
  auto [status, std_out, std_err] = Run("MySuite.GoogleTestExpect");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  ExpectTargetAbort(status, std_err);

#ifndef FUZZTEST_USE_CENTIPEDE
  // There is a stack both on stdout and stderr.
  EXPECT_THAT_LOG(std_out, HasSubstr("GoogleTestExpect("));
  EXPECT_THAT_LOG(std_err, HasSubstr("GoogleTestExpect("));

  // There is the repro example only on stderr.
  EXPECT_THAT_LOG(std_out,
                  Not(HasReproducerTest("MySuite", "GoogleTestExpect", ".*")));
#endif
  EXPECT_THAT_LOG(std_err,
                  HasReproducerTest("MySuite", "GoogleTestExpect", ".*"));
}

TEST_P(FuzzingModeCrashFindingTest, GoogleTestAssertionsStopTheFuzzer) {
  auto [status, std_out, std_err] = Run("MySuite.GoogleTestAssert");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  ExpectTargetAbort(status, std_err);

#ifndef FUZZTEST_USE_CENTIPEDE
  // There is a stack both on stdout and stderr.
  EXPECT_THAT_LOG(std_out, HasSubstr("GoogleTestAssert("));
  EXPECT_THAT_LOG(std_err, HasSubstr("GoogleTestAssert("));

  // There is the repro example only on stderr.
  EXPECT_THAT_LOG(std_out,
                  Not(HasReproducerTest("MySuite", "GoogleTestAssert", ".*")));

#endif
  EXPECT_THAT_LOG(std_err,
                  HasReproducerTest("MySuite", "GoogleTestAssert", ".*"));
}

TEST_P(FuzzingModeCrashFindingTest, MappedDomainShowsMappedValue) {
  auto [status, std_out, std_err] = Run("MySuite.Mapping");
  EXPECT_THAT_LOG(
      std_err,
      AllOf(
          HasSubstr("argument 0: \"12 monkeys\""),
          HasReproducerTest(
              "MySuite", "Mapping",
              // Account for the possibility that the symbol
              // NumberOfAnimalsToString may be mangled.
              R"re(.*NumberOfAnimalsToString.*\(TimesTwo\(6\), "monkey"\))re")));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, FlatMappedDomainShowsMappedValue) {
  auto [status, std_out, std_err] = Run("MySuite.FlatMapping");
  EXPECT_THAT_LOG(std_err, AllOf(HasSubstr("argument 0: {\"abc\", 2}"),
                                 HasReproducerTest("MySuite", "FlatMapping",
                                                   "{\"abc\", 2}")));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, FlatMapPassesWhenCorrect) {
  auto [status, std_out, std_err] =
      Run("MySuite.FlatMapPassesWhenCorrect", kDefaultTargetBinary,
          /*env=*/{}, /*timeout=*/absl::Seconds(10));
  EXPECT_THAT(status, Eq(ExitCode(0)));
}

TEST_P(FuzzingModeCrashFindingTest, FilterDomainShowsOnlyFilteredValues) {
  auto [status, std_out, std_err] = Run("MySuite.Filtering");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: 8"));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 1: 9"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, BadFilterTriggersAnAbort) {
  auto [status, std_out, std_err] = Run("MySuite.BadFilter");
  EXPECT_THAT_LOG(std_err, HasSubstr("Ineffective use of Filter()"));
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("argument 0:")));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, BadWithMinSizeTriggersAnAbort) {
  auto [status, std_out, std_err] = Run("MySuite.BadWithMinSize");
  EXPECT_THAT_LOG(std_err, HasSubstr("Ineffective use of WithSize()"));
  EXPECT_THAT_LOG(std_err, Not(HasSubstr("argument 0:")));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, SmartPointer) {
  auto [status, std_out, std_err] = Run("MySuite.SmartPointer");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: (1"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, UnprintableTypeRunsAndPrintsSomething) {
  auto [status, std_out, std_err] = Run("MySuite.UsesUnprintableType");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: <unprintable value>"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, MyStructTestArbitraryCanPrint) {
  auto [status, std_out, std_err] = Run("MySuite.MyStructArbitrary");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: MyStruct{0, \"X"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, MyStructTestWithDomainsCanPrint) {
  auto [status, std_out, std_err] = Run("MySuite.MyStructWithDomains");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: MyStruct{0, \"X"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, ConstructorPrintsSomething) {
  auto [status, std_out, std_err] = Run("MySuite.ConstructorWithDomains");
  EXPECT_THAT_LOG(std_err, HasSubstr("\"ccc\""));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, SeedInputIsUsed) {
  auto [status, std_out, std_err] = Run("MySuite.SeedInputIsUsed");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: {9439518, 21, 49153}"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest,
       SeedInputIsUsedInProtobufsWithInternalMappings) {
  auto [status, std_out, std_err] =
      Run("MySuite.SeedInputIsUsedInProtobufsWithInternalMappings");
  EXPECT_THAT_LOG(std_err, HasSubstr("subproto_i32: 9439518"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, SeedInputIsUsedForMutation) {
  auto [status, std_out, std_err] = Run("MySuite.SeedInputIsUsedForMutation");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: {1979, 9791, 1234, 6789"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, UsesManualDictionary) {
  auto [status, std_out, std_err] = Run("MySuite.StringPermutationTest");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"9876543210\""));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, UsesSeededDomain) {
  auto [status, std_out, std_err] = Run("MySuite.StringPermutationWithSeeds");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"9876543210\""));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, UsesSeedFromSeedProvider) {
  auto [status, std_out, std_err] =
      Run("MySuite.StringPermutationWithSeedProvider");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"9876543210\""));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, UsesSeedFromSeedProviderOnFixture) {
  auto [status, std_out, std_err] =
      Run("SeededFixture.StringPermutationWithSeedProvider");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"9876543210\""));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest,
       FunctionPointerAliasFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] =
      Run("MySuite.FunctionPointerAliasesAreFuzzable");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest,
       FunctionReferenceAliasFindsAbortInFuzzingMode) {
  auto [status, std_out, std_err] =
      Run("MySuite.FunctionReferenceAliasesAreFuzzable");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, FuzzTestCanFindStackOverflows) {
  auto [status, std_out, std_err] = Run("MySuite.DataDependentStackOverflow");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: "));
  // 128 KiB is the default stack limit.
  ExpectStackLimitExceededMessage(std_err, 128 * 1024);
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest,
       StackCalculationWorksWithAlternateStackForSignalHandlers) {
  auto [status, std_out, std_err] =
      Run("AlternateSignalStackFixture."
          "StackCalculationWorksWithAlternateStackForSignalHandlers");
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: 123456789"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, InputsAreSkippedWhenRequestedInTests) {
  auto [status, std_out, std_err] =
      Run("MySuite.SkipInputs", kDefaultTargetBinary);
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: 123456789"));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, AsanCrashMetadataIsDumpedIfEnvVarIsSet) {
#ifndef ADDRESS_SANITIZER
  GTEST_SKIP() << "Skipping crash finding test for ASAN errors without ASAN";
#endif
  TempDir out_dir;
  const std::string crash_metadata_path = out_dir.path() / "crash_metadata";
  auto [status, std_out, std_err] =
      Run("MySuite.BufferOverreadWithString", kDefaultTargetBinary,
          {{"FUZZTEST_CRASH_METADATA_PATH", crash_metadata_path}});

  EXPECT_THAT(ReadFile(crash_metadata_path),
              Optional(Eq("heap-buffer-overflow")));
}

TEST_P(FuzzingModeCrashFindingTest, SignalCrashMetadataIsDumpedIfEnvVarIsSet) {
  TempDir out_dir;
  const std::string crash_metadata_path = out_dir.path() / "crash_metadata";
  auto [status, std_out, std_err] =
      Run("MySuite.Aborts", kDefaultTargetBinary,
          {{"FUZZTEST_CRASH_METADATA_PATH", crash_metadata_path}});

  EXPECT_THAT(ReadFile(crash_metadata_path), Optional(Eq("SIGABRT")));
}

TEST_P(FuzzingModeCrashFindingTest, GTestCrashMetadataIsDumpedIfEnvVarIsSet) {
  TempDir out_dir;
  const std::string crash_metadata_path = out_dir.path() / "crash_metadata";
  auto [status, std_out, std_err] =
      Run("MySuite.GoogleTestExpect", kDefaultTargetBinary,
          {{"FUZZTEST_CRASH_METADATA_PATH", crash_metadata_path}});

  EXPECT_THAT(ReadFile(crash_metadata_path),
              Optional(Eq("GoogleTest assertion failure")));
}

TEST_P(FuzzingModeCrashFindingTest,
       SetupFailureCrashMetadataIsDumpedIfEnvVarIsSet) {
  TempDir out_dir;
  const std::string crash_metadata_path = out_dir.path() / "crash_metadata";
  auto [status, std_out, std_err] =
      Run("FaultySetupTest.NoOp", kDefaultTargetBinary,
          {{"FUZZTEST_CRASH_METADATA_PATH", crash_metadata_path}});

  EXPECT_THAT(ReadFile(crash_metadata_path),
              Optional(Eq("SETUP FAILURE: SIGABRT")));
}

TEST_P(FuzzingModeCrashFindingTest,
       CustomMutatorAndMutateCalllbackWorksForLLVMFuzzer) {
  TempDir out_dir;
  auto [status, std_out, std_err] =
      Run("LLVMFuzzer.TestOneInput", "testdata/llvm_fuzzer_with_custom_mutator",
          /*env=*/
          {
          },
          /*timeout=*/absl::Seconds(30));
  EXPECT_THAT_LOG(std_err, HasSubstr("argument 0: \"ahmfn\""));
  ExpectTargetAbort(status, std_err);
}

TEST_P(FuzzingModeCrashFindingTest, FlatbuffersFailsWhenFieldsAreNotDefault) {
  TempDir out_dir;
  auto [status, std_out, std_err] =
      Run("MySuite.FlatbuffersFailsWhenFieldsAreNotDefault");
  EXPECT_THAT_LOG(std_err,
                  AllOf(HasSubstr("argument 0: {b: ("),  // b
                        HasSubstr("i8: ("),              // i8
                        HasSubstr("i16: ("),             // i16
                        HasSubstr("i32: ("),             // i32
                        HasSubstr("i64: ("),             // i64
                        HasSubstr("u8: ("),              // u8
                        HasSubstr("u16: ("),             // u16
                        HasSubstr("u32: ("),             // u32
                        HasSubstr("u64: ("),             // u64
                        HasSubstr("f: ("),               // f
                        HasSubstr("d: ("),               // d
                        HasSubstr("str: "),              // str
                        HasSubstr("ei8: ("),             // ei8
                        HasSubstr("ei16: ("),            // ei16
                        HasSubstr("ei32: ("),            // ei32
                        HasSubstr("ei64: ("),            // ei64
                        HasSubstr("eu8: ("),             // eu8
                        HasSubstr("eu16: ("),            // eu16
                        HasSubstr("eu32: ("),            // eu32
                        HasSubstr("eu64: (")));          // eu64
  ExpectTargetAbort(status, std_err);
}

INSTANTIATE_TEST_SUITE_P(FuzzingModeCrashFindingTestWithExecutionModel,
                         FuzzingModeCrashFindingTest,
                         testing::ValuesIn(GetAvailableExecutionModels()));

}  // namespace
}  // namespace fuzztest::internal