src/output_stream_test.cc

// Copyright 2025 Google Inc. All Rights Reserved.
//
// 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 "output_stream.h"

#include "test.h"

/// A class that wraps an integer token and provides a ToString() method.
/// Used to verify that OutputStream::operator<< correctly supports it.
struct TestToken {
  TestToken(int x) : x_(x) {}
  std::string ToString() const { return StringFormat("Token(%d)", x_); }
  int x_;
};

TEST(OutputStreamTest, StringOutputStream) {
  StringOutputStream s;

  EXPECT_TRUE(s.str().empty());

  s.Write("foobar", 6);
  EXPECT_EQ(s.str(), "foobar");
  EXPECT_EQ(s.Take(), "foobar");
  EXPECT_TRUE(s.str().empty());

  s.Write("Hello World!", 10);
  EXPECT_EQ(s.str(), "Hello Worl");
  EXPECT_EQ(s.Take(), "Hello Worl");

  s.Format("Hello %s", "World!");
  EXPECT_EQ(s.Take(), "Hello World!");

  s << int(10);
  EXPECT_EQ(s.Take(), "10");

  s << int(-42);
  EXPECT_EQ(s.Take(), "-42");

  s << char('c');
  EXPECT_EQ(s.Take(), "c");

  s << static_cast<unsigned char>('c');
  EXPECT_EQ(s.Take(), "99");

  s << true;
  EXPECT_EQ(s.Take(), "true");

  s << false;
  EXPECT_EQ(s.Take(), "false");

  s << "This is " << std::string("a") << " concatenation of " << 5 << " parts";
  EXPECT_EQ(s.Take(), "This is a concatenation of 5 parts");

  s << TestToken(10) << ", " << TestToken(20);
  EXPECT_EQ(s.Take(), "Token(10), Token(20)");
}