用cpp做C单元测试

发布: 2008-2-03 13:58 | 作者: 网络转载 | 来源: 网络转载 | 查看: 160次 | 进入软件测试论坛讨论

编写测试用例

　　一旦我们知道我们要测什么之后，我们就可以写测试用例了。我们能够执行所有的我们需要的操作：使用普通库函数，第三方库，win32api库函数，或简单使用c++内部操作

　　有时候，我们需要调用外部辅助文件或者数据库，比较外部文件和内部数据是否一致。

　　每发现一个错误时9比如发现内部数据和外部数据不同我们就创建一个异常，使用 CPPUNIT_FAIL(message) 来显示异常信息。

　　检测一个条件就使用
CPPUNIT_ASSERT(condition):如果为false就抛出异常
CPPUNIT_ASSERT_MESSAGE(message, condition): 如果为false就抛出制定的信息。
CPPUNIT_ASSERT_EQUAL(expected,current): 检测期望值
CPPUNIT_ASSERT_EQUAL_MESSAGE(message,expected,current): 当比较值不相等时候抛出的制定的信息。
CPPUNIT_ASSERT_DOUBLES_EQUAL(expected,current,delta): 带精度的比较
　　下面是测试loadTest的例子，
//
// These are correct values stored in auxiliar file
//
#define AUX_FILENAME "ok_data.dat"
#define FILE_NUMBER 19
#define FILE_STRING "this is correct text stored in auxiliar file"

void DiskDataTestCase::loadTest()
{
// convert from relative to absolute path
TCHAR absoluteFilename[MAX_PATH];
DWORD size = MAX_PATH;

strcpy(absoluteFilename, AUX_FILENAME);
CPPUNIT_ASSERT( RelativeToAbsolutePath(absoluteFilename, &size) );

// executes action
CPPUNIT_ASSERT( fixture-＞load(absoluteFilename) );

// ...and check results with assertions
LPDATA loadedData = fixture-＞getData();

CPPUNIT_ASSERT(loadedData != NULL);
CPPUNIT_ASSERT_EQUAL(FILE_NUMBER, loadedData-＞number);
CPPUNIT_ASSERT( 0 == strcmp(FILE_STRING,
fixture-＞getData()-＞string) );
}

　　在这个case我们得到四个可能的错误：

load method's return value
getData method's return value
number structure member's value
string structure member's value

　　第二个用例也是相似的。但是困难点，我们需要使用已知的数据来填充fixture，把它存在磁盘临时文件里，然后打开两个文件（新的和辅助文件），读并比较内容，两者如一致就正确

void DiskDataTestCase::storeTest()
{
DATA d;
DWORD tmpSize, auxSize;
BYTE *tmpBuff, *auxBuff;
TCHAR absoluteFilename[MAX_PATH];
DWORD size = MAX_PATH;

// configures structure with known data
d.number = FILE_NUMBER;
strcpy(d.string, FILE_STRING);

// convert from relative to absolute path

strcpy(absoluteFilename, AUX_FILENAME);
CPPUNIT_ASSERT( RelativeToAbsolutePath(absoluteFilename, &size) );

// executes action
fixture-＞setData(&d);
CPPUNIT_ASSERT( fixture-＞store("data.tmp") );

// Read both files contents and check results
// ReadAllFileInMemory is an auxiliar function which allocates a buffer
// and save all file content inside it. Caller should release the buffer.
tmpSize = ReadAllFileInMemory("data.tmp", tmpBuff);
auxSize = ReadAllFileInMemory(absoluteFilename, auxBuff);

// files must exist
CPPUNIT_ASSERT_MESSAGE("New file doesn't exists?", tmpSize ＞ 0);
CPPUNIT_ASSERT_MESSAGE("Aux file doesn't exists?", auxSize ＞ 0);

// sizes must be valid
CPPUNIT_ASSERT(tmpSize != 0xFFFFFFFF);
CPPUNIT_ASSERT(auxSize != 0xFFFFFFFF);

// buffers must be valid
CPPUNIT_ASSERT(tmpBuff != NULL);
CPPUNIT_ASSERT(auxBuff != NULL);

// both file's sizes must be the same as DATA's size
CPPUNIT_ASSERT_EQUAL((DWORD) sizeof(DATA), tmpSize);
CPPUNIT_ASSERT_EQUAL(auxSize, tmpSize);

// both files content must be the same
CPPUNIT_ASSERT( 0 == memcmp(tmpBuff, auxBuff, sizeof(DATA)) );

delete [] tmpBuff;
delete [] auxBuff;

::DeleteFile("data.tmp");
}

调用用户接口

　　最后，我们看看用一个mfc 对话框（TestRunner.dll）用来说明。

　　我们需要在我们的初始化函数中做如下初始化

#include ＜cppunit/ui/mfc/TestRunner.h＞
#include ＜cppunit/extensions/TestFactoryRegistry.h＞

BOOL CMy_TestsApp::InitInstance()
{
....

// declare a test runner, fill it with our registered tests and run them
CppUnit::MfcUi::TestRunner runner;

runner.addTest( CppUnit::TestFactoryRegistry::getRegistry().makeTest() );

runner.run();

return TRUE;
}

　　只要定义一个test的实例，然后注册所有用例，在跑case。