text: // Copyright 2020 The XLS 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
  //
  //      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 "xls/common/logging/capture_stream.h"
  
  #include <cstdio>
  
  #include "gmock/gmock.h"
  #include "gtest/gtest.h"
  #include "absl/status/statusor.h"
  #include "xls/common/status/matchers.h"
  
  namespace xls {
  namespace testing {
  namespace {
  
  using status_testing::IsOkAndHolds;
  using ::testing::Eq;
  
  TEST(CaptureStreamTest, CaptureStdoutData) {
    absl::StatusOr<std::string> data = CaptureStream(STDOUT_FILENO, [] {
      fprintf(stdout, "Hello!");
      fprintf(stderr, "This should be ignored.");
    });
    EXPECT_THAT(data, IsOkAndHolds(Eq("Hello!")));
  }
  
  TEST(CaptureStreamTest, CaptureStderrData) {
    absl::StatusOr<std::string> data = CaptureStream(STDERR_FILENO, [] {
      fprintf(stderr, "Some output.\nHello!");
      fprintf(stdout, "This should be ignored.");
    });
    EXPECT_THAT(data, IsOkAndHolds(Eq("Some output.\nHello!")));
  }
  
  }  // namespace
  }  // namespace testing
  }  // namespace xls
  