GTEST安装以及简单实例使用指南

GTEST 编译过程错误

GTEST安装以及简单使用指南

很多博客都写了关于GTEST的安装指南，其实过程并不复杂，但其中有一些坑还是想说一下。

1 正常安装过程

git clone http://github.com/google/googletest
cd googletest
mkdir build && cd build
cmake ..
make
make install

2 ⚠️注意点

1. 安装gtest前确保安装了cmake
2. 在安装过程中如果有出现一下错误

fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.
make[2]: *** [googletest/CMakeFiles/gtest.dir/src/gtest-all.cc.o] Error 1
make[1]: *** [googletest/CMakeFiles/gtest.dir/all] Error 2
make: *** [all] Error 2

或者你应该可以看到，在上面的报错信息中有 xxx is a C++11 extenstion等等，请按如下代码进行编译，

git clone https://github.com/google/googletest.git
cd googletest
mkdir build
cd build
cmake -DCMAKE_CXX_COMPILER="c++" -DCMAKE_CXX_FLAGS="-std=c++11 -stdlib=libc++" ../
make
sudo make install

如果上述代码依然失败，请删除 -stdlib=libc++ 该选项。我是在删除该选项之后成功的，OS为MacOS，ubuntu应该同理。

3 简单示例

使用googletest文件下的googletest文件夹中的sample进行简单的测试。

我把代码贴在这里吧，

// Copyright 2005, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// A sample program demonstrating using Google C++ testing framework.

#ifndef GTEST_SAMPLES_SAMPLE2_H_
#define GTEST_SAMPLES_SAMPLE2_H_

#include <string.h>


// A simple string class.
class MyString {
 private:
  const char* c_string_;
  const MyString& operator=(const MyString& rhs);

 public:
  // Clones a 0-terminated C string, allocating memory using new.
  static const char* CloneCString(const char* a_c_string);

  ////////////////////////////////////////////////////////////
  //
  // C'tors

  // The default c'tor constructs a NULL string.
  MyString() : c_string_(nullptr) {}

  // Constructs a MyString by cloning a 0-terminated C string.
  explicit MyString(const char* a_c_string) : c_string_(nullptr) {
    Set(a_c_string);
  }

  // Copy c'tor
  MyString(const MyString& string) : c_string_(nullptr) {
    Set(string.c_string_);
  }

  ////////////////////////////////////////////////////////////
  //
  // D'tor.  MyString is intended to be a final class, so the d'tor
  // doesn't need to be virtual.
  ~MyString() { delete[] c_string_; }

  // Gets the 0-terminated C string this MyString object represents.
  const char* c_string() const { return c_string_; }

  size_t Length() const { return c_string_ == nullptr ? 0 : strlen(c_string_); }

  // Sets the 0-terminated C string this MyString object represents.
  void Set(const char* c_string);
};


#endif  // GTEST_SAMPLES_SAMPLE2_H_

#include "sample2.h"

#include <string.h>

// Clones a 0-terminated C string, allocating memory using new.
const char* MyString::CloneCString(const char* a_c_string) {
  if (a_c_string == nullptr) return nullptr;

  const size_t len = strlen(a_c_string);
  char* const clone = new char[ len + 1 ];
  memcpy(clone, a_c_string, len + 1);

  return clone;
}

// Sets the 0-terminated C string this MyString object
// represents.
void MyString::Set(const char* a_c_string) {
  // Makes sure this works when c_string == c_string_
  const char* const temp = MyString::CloneCString(a_c_string);
  delete[] c_string_;
  c_string_ = temp;
}

然后再编写一个自己的main文件即可，

#include "sample2.h"
#include<gtest/gtest.h>
int main(int argc,char* argv[])
{
	testing::InitGoogleTest();
	RUN_ALL_TESTS();
	return 0;
}

使用以下命令，或者根据实际情况修改文件名即可。

g++ test.cpp -std=c++11 -lgtest

最后的结果如下