leveldb分析——单元测试工具

leveldb中自己实现了一个简单的单元测试工具,下面是一个对CRC类测试的一个例子

class CRC { };
TEST(CRC, Extend) {
   ASSERT_EQ(Value("hello world", 11),
   Extend(Value("hello ", 6), "world", 5));
}

 int main(int argc, char** argv) {
   return leveldb::test::RunAllTests();
 }

TEST() 和RunAllTests()空间是怎么实现的呢?我们来看看源码:

#define TEST(base,name)                                                 \
class TCONCAT(_Test_,name) : public base {                              \
 public:                                                                \
  void _Run();                                                          \
  static void _RunIt() {                                                \
    TCONCAT(_Test_,name) t;                                             \
    t._Run();                                                           \
  }                                                                     \
};                                                                      \
bool TCONCAT(_Test_ignored_,name) =                                     \
  ::leveldb::test::RegisterTest(#base, #name, &TCONCAT(_Test_,name)::_RunIt); \
void TCONCAT(_Test_,name)::_Run()

 对上面的测试程序实际展开后如下:

class _Test_Extend : public CRC {
 public:
  void _Run();
  static void _RunIt(){
    _Test_Extend t;
    t._Run();
  }
};
bool _Test_ignored_Extend = ::leveldb::test::Register("CRC","Extend",&_Test_Extend::_RunIt());
void _Test_Extend::Run(){
   ASSERT_EQ(Value("hello world", 11),
   Extend(Value("hello ", 6), "world", 5));
}

注册过程:

struct Test {
  const char* base;
  const char* name;
  void (*func)();
};
std::vector<Test>* tests;
}

bool RegisterTest(const char* base, const char* name, void (*func)()) {
  if (tests == NULL) {
    tests = new std::vector<Test>;
  }
  Test t;
  t.base = base;
  t.name = name;
  t.func = func;
  tests->push_back(t);
  return true;
}

 运行过程:

int RunAllTests() {
  int num = 0;
  if (tests != NULL) {
    for (int i = 0; i < tests->size(); i++) {
      const Test& t = (*tests)[i];
      }
      fprintf(stderr, "==== Test %s.%s\n", t.base, t.name);
      (*t.func)();
      ++num;
    }
  }
  fprintf(stderr, "==== PASSED %d tests\n", num);
  return 0;
}

 

posted @ 2016-01-21 22:32  xey_csu  阅读(566)  评论(0编辑  收藏  举报