stripping_test.cc | Explore in Territory

//
// Copyright 2022 The Abseil Authors.
//
// 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
//
//      https://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.
//
// Tests for stripping of literal strings.
// ---------------------------------------
//
// When a `LOG` statement can be trivially proved at compile time to never fire,
// e.g. due to `ABSL_MIN_LOG_LEVEL`, `NDEBUG`, or some explicit condition, data
// streamed in can be dropped from the compiled program completely if they are
// not used elsewhere.  This most commonly affects string literals, which users
// often want to strip to reduce binary size and/or redact information about
// their program's internals (e.g. in a release build).
//
// These tests log strings and then validate whether they appear in the compiled
// binary.  This is done by opening the file corresponding to the running test
// and running a simple string search on its contents.  The strings to be logged
// and searched for must be unique, and we must take care not to emit them into
// the binary in any other place, e.g. when searching for them.  The latter is
// accomplished by computing them using base64; the source string appears in the
// binary but the target string is computed at runtime.

#include <stdio.h>

#if defined(__MACH__)
#include <mach-o/dyld.h>
#elif defined(_WIN32)
#include <Windows.h>
#include <tchar.h>
#endif

#include <algorithm>
#include <functional>
#include <memory>
#include <ostream>
#include <string>

#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/base/internal/strerror.h"
#include "absl/base/log_severity.h"
#include "absl/flags/internal/program_name.h"
#include "absl/log/check.h"
#include "absl/log/internal/test_helpers.h"
#include "absl/log/log.h"
#include "absl/status/status.h"
#include "absl/strings/escaping.h"
#include "absl/strings/str_format.h"
#include "absl/strings/string_view.h"

// Set a flag that controls whether we actually execute fatal statements, but
// prevent the compiler from optimizing it out.
static volatile bool kReallyDie = …;

namespace {
_;
Eq;
NotNull;

kAbslMinLogLevel;

std::string Base64UnescapeOrDie(absl::string_view data) { … }

// -----------------------------------------------------------------------------
// A Googletest matcher which searches the running binary for a given string
// -----------------------------------------------------------------------------

// This matcher is used to validate that literal strings streamed into
// `LOG` statements that ought to be compiled out (e.g. `LOG_IF(INFO, false)`)
// do not appear in the binary.
//
// Note that passing the string to be sought directly to `FileHasSubstr()` all
// but forces its inclusion in the binary regardless of the logging library's
// behavior. For example:
//
//   LOG_IF(INFO, false) << "you're the man now dog";
//   // This will always pass:
//   // EXPECT_THAT(fp, FileHasSubstr("you're the man now dog"));
//   // So use this instead:
//   EXPECT_THAT(fp, FileHasSubstr(
//       Base64UnescapeOrDie("eW91J3JlIHRoZSBtYW4gbm93IGRvZw==")));

class FileHasSubstrMatcher final : public ::testing::MatcherInterface<FILE*> { … };

class StrippingTest : public ::testing::Test { … };

// This tests whether out methodology for testing stripping works on this
// platform by looking for one string that definitely ought to be there and one
// that definitely ought not to.  If this fails, none of the `StrippingTest`s
// are going to produce meaningful results.
TEST_F(StrippingTest, Control) { … }

TEST_F(StrippingTest, Literal) { … }

TEST_F(StrippingTest, LiteralInExpression) { … }

TEST_F(StrippingTest, Fatal) { … }

TEST_F(StrippingTest, DFatal) { … }

TEST_F(StrippingTest, Level) { … }

TEST_F(StrippingTest, Check) { … }

TEST_F(StrippingTest, CheckOp) { … }

TEST_F(StrippingTest, CheckStrOp) { … }

TEST_F(StrippingTest, CheckOk) { … }

}  // namespace
chromium/third_party/abseil-cpp/absl/log/stripping_test.cc
