如果你還沒有搭建gtest框架，可以參考我之前的博客：http://www.cnblogs.com/jycboy/p/6001153.html。。
你把github上的項目導來之後，github地址：https://github.com/google/googletest，在目錄：..(你的目錄)\googletest-master\googletest\samples是你的samples文件夾。
在VS中創建項目：GtestSamples
把對應的代碼加入到這裡邊：sample1.h、sample1.cc、sample1_unittest.cc.
在sample1.cc中是你要測試的函數：
// 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 squre 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;
}
在sample1_unittest.cc中，是你編寫的測試：
有兩個測試用例：Factorial、IsPrime;每個測試用例對應三個test。
extern int Factorial(int n);
extern bool IsPrime(int n);
// Tests Factorial().
// Tests factorial of negative numbers.
TEST(FactorialTest, Negative) {
// This test is named "Negative", and belongs to the "FactorialTest"
// test case.
EXPECT_EQ(1, Factorial(-5));
EXPECT_EQ(2, Factorial(-1)); //如果是ASSERT_EQ，後邊的EXPECT_GT將不在執行；如果是EXPECT_EQ，後邊的測試EXPECT_GT繼續執行
EXPECT_GT(Factorial(-10), 0);
ASSERT_EQ(3, Factorial(-1));
// <TechnicalDetails>
//
// EXPECT_EQ(expected, actual) is the same as
//
// EXPECT_TRUE((expected) == (actual))
//
// except that it will print both the expected value and the actual
// value when the assertion fails. This is very helpful for
// debugging. Therefore in this case EXPECT_EQ is preferred.
//
// On the other hand, EXPECT_TRUE accepts any Boolean expression,
// and is thus more general.
//
// </TechnicalDetails>
}
// Tests factorial of 0.
TEST(FactorialTest, Zero) {
EXPECT_EQ(1, Factorial(0));
}
// Tests factorial of positive numbers.
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()
// Tests negative input.
TEST(IsPrimeTest, Negative) {
// This test belongs to the IsPrimeTest test case.
EXPECT_FALSE(IsPrime(-1));
EXPECT_FALSE(IsPrime(-2));
EXPECT_FALSE(IsPrime(INT_MIN));
}
// Tests some trivial cases.
TEST(IsPrimeTest, Trivial) {
EXPECT_FALSE(IsPrime(0));
EXPECT_FALSE(IsPrime(1));
EXPECT_TRUE(IsPrime(2));
EXPECT_TRUE(IsPrime(3));
}
// Tests positive input.
TEST(IsPrimeTest, Positive) {
EXPECT_FALSE(IsPrime(4));
EXPECT_TRUE(IsPrime(5));
EXPECT_FALSE(IsPrime(6));
EXPECT_TRUE(IsPrime(23));
}
// Step 3. Call RUN_ALL_TESTS() in main().
//
// We do this by linking in src/gtest_main.cc file, which consists of
// a main() function which calls RUN_ALL_TESTS() for us.
//
// This runs all the tests you've defined, prints the result, and
// returns 0 if successful, or 1 otherwise.
//
// Did you notice that we didn't register the tests? The
// RUN_ALL_TESTS() macro magically knows about all the tests we
// defined. Isn't this convenient?
Step 1.包括必要的頭文件，以便聲明測試邏輯需要的東西。不要忘了 gtest.h
#include <limits.h> #include "sample1.h" #include <gtest/gtest.h>
Step 2. 使用TEST宏來定義測試。
TEST有兩個參數：測試用例名稱和測試名稱。
使用宏後，應該在一對大括號之間定義測試邏輯。 您可以使用一堆宏來指示測試的成功或失敗。 EXPECT_TRUE和EXPECT_EQ是此類宏的示例。 有關完整列表，請參閱gtest.h。
技術細節：
在Google Test中，測試分為多個測試用例。你應該將邏輯相關的測試放入同一個測試用例。
測試用例名和測試名都應該是有效的C ++標識符。 並且你不應該在名稱中使用下劃線（_）。
Google測試保證您定義的每個測試只運行一次，但不能保證測試執行的順序。 因此，您應該以這樣一種方式編寫測試，使得它們的結果不依賴於它們的順序。
TEST(FactorialTest, Negative) {
// This test is named "Negative", and belongs to the "FactorialTest"
// test case.
EXPECT_EQ(1, Factorial(-5));
EXPECT_EQ(2, Factorial(-1)); //如果是ASSERT_EQ，後邊的EXPECT_GT將不在執行；如果是EXPECT_EQ，後邊的測試EXPECT_GT繼續執行
EXPECT_GT(Factorial(-10), 0);
EXPECT_TRUE(2 == Factorial(-7));//這個錯誤失敗信息打印的是true或false，不會打印值
ASSERT_EQ(3, Factorial(-1));
}
技術細節：
上面的EXPECT_EQ(1, Factorial(-1))和EXPECT_TRUE(1==Factorial(-1))的作用是一樣的，但是當失敗時，EXPECT_EQ會打印期望值和實際值，而EXPECT_TRUE是會打印true、false。所以優先選用EXPECT_EQ。
Step 3. Call RUN_ALL_TESTS() in main().
int main(int argc, char **argv) {
//printf("Running main() from gtest_main.cc\n");
testing::InitGoogleTest(&argc,argv);
return RUN_ALL_TESTS();
}
**RUN_ALL_TESTS() 會自動調用所有的測試。
之前的兩篇博客：
之後會陸續更新，一直到GMock，但願我不會太懶，。。。。
