环境搭建
gtest下载地址： https://github.com/google/googletest
下载方法是：git clone https://github.com/google/googletest.git
安装方法是：
$ cd googletest
注意：如果在make 过程中报错，可在CMakeLists.txt 中增加如下行，再执行下面的命令: SET(CMAKE_CXX_FLAGS "-std=c++11")
$ cmake .
$ make
然后在lib目录下会生成：libgmock.a libgmock_main.a libgtest.a libgtest_main.a
最后我们再sudo make install。
不需要自己写mian
g++ sample1.cc sample1_unittest.cc -lgtest -std=c++11 -lgtest_main -lpthread -o test1
#include "sample1.h"
// Returns n! (the factorial of n). For negative n, n! is defined to be 1.
int Factorial(int n) {
int result = 1;
for (int i = 1; i <= n; i++) {
result *= i;
}
return result;
}
// Returns true iff n is a prime number.
bool IsPrime(int n) {
// Trivial case 1: small numbers
if (n <= 1) return false;
// Trivial case 2: even numbers
if (n % 2 == 0) return n == 2;
// Now, we have that n is odd and n >= 3.
// Try to divide n by every odd number i, starting from 3
for (int i = 3; ; i += 2) {
// We only have to try i up to the square root of n
if (i > n/i) break;
// Now, we have i <= n/i < n.
// If n is divisible by i, n is not prime.
if (n % i == 0) return false;
}
// n has no integer factor in the range (1, n), and thus is prime.
return true;
}
//这两个函数定义在sample1.cc文件里，函数申明在sample1.h里：
#ifndef GTEST_SAMPLES_SAMPLE1_H_
#define GTEST_SAMPLES_SAMPLE1_H_
// Returns n! (the factorial of n). For negative n, n! is defined to be 1.
int Factorial(int n);
// Returns true iff n is a prime number.
bool IsPrime(int n);
#endif
自写测试用例
#include <limits.h>
#include "sample1.h"
#include "gtest/gtest.h"
namespace {
TEST(FactorialTest, Negative) {//测试对于复数得场景
// This test is named "Negative", and belongs to the "FactorialTest"
// test case.
EXPECT_EQ(1, Factorial(-5));//断言测试 参数1 断言返回是多少 参数2函数并带参数
EXPECT_EQ(1, Factorial(-1));
EXPECT_GT(Factorial(-10), 0);
}
TEST(FactorialTest, Zero) {//测试对正数得场景
EXPECT_EQ(1, Factorial(0));
}
TEST(FactorialTest, Positive) {
EXPECT_EQ(1, Factorial(1));
EXPECT_EQ(2, Factorial(2));
EXPECT_EQ(6, Factorial(3));
EXPECT_EQ(40320, Factorial(8));
}
// Tests IsPrime()
TEST(IsPrimeTest, Negative) {
EXPECT_FALSE(IsPrime(-1));
EXPECT_FALSE(IsPrime(-2));
EXPECT_FALSE(IsPrime(INT_MIN));
}
TEST(IsPrimeTest, Trivial) {
EXPECT_FALSE(IsPrime(0));//返回得是假
EXPECT_FALSE(IsPrime(1));
EXPECT_TRUE(IsPrime(2));//返回得是真
EXPECT_TRUE(IsPrime(3));
}
TEST(IsPrimeTest, Positive) {
EXPECT_FALSE(IsPrime(4));
EXPECT_TRUE(IsPrime(5));
EXPECT_FALSE(IsPrime(6));
EXPECT_TRUE(IsPrime(23));
}
} // namespace
TEST是gtest的测试宏，我们的测试用例必须按照这样格式写，
isPrimeTest是测试套的名字，一个测试套下可以有多个测试用例，
那么Positive、Trivial就是我们测试用例的名称，EXPECT_EQ、EXPECT_FALSE
和EXPECT_TRUE等等，都是gtest提供的测试断言，比如 EXPECT_EQ(1, Factorial(1));
就是表示Factorial(1)和1是不是相等的，如果是则表示EXPECT_EQ会返回成功，否则失败
，也即我们测试用例会失败或者成功。
