Python Pytest 链式调用风格 的 自定义断言库

使用示例

test_users.py

@allure.title("获取用户列表")
def test_users(self, api):
    api.request()
    api.asserts(200)
    api.expect('$..nodes').not_.to_be_empty()

*结合 Pytest 还可以增加 这些方法，就不提供实际代码了。

Expect(1).skip.to_be(1)

Expect(1).soft.to_be(1)

Expect(1).retry.to_be(1)

自定义断言库

expect.py

class Expect(object):
    def __init__(self, item1: object):
        self.item1 = item1
        self.reverse = False
    def __reverse_result_if_not(self, result):
        return not result if self.reverse else result
    @property
    def not_(self):
        self.reverse = not self.reverse
        return self
    def to_be(self, item2: object):
        assert self.__reverse_result_if_not(self.item1 is item2)
        return self
    def to_be_true(self):
        self.to_be(True)
        return self
    def to_be_false(self):
        self.to_be(False)
        return self
    def to_be_none(self):
        self.to_be(None)
        return self
    def to_equals(self, item2: object):
        assert self.__reverse_result_if_not(self.item1 == item2)
        return self
    def to_be_in(self, item2: object):
        assert self.__reverse_result_if_not(self.item1 in item2)
        return self
    def to_be_contains(self, item2: object):
        assert self.__reverse_result_if_not(item2 in self.item1)
        return self
    def to_less_than(self, item2: object, allow_equal=False):
        if allow_equal:
            assert self.__reverse_result_if_not(self.item1 = item2)
        else:
            assert self.__reverse_result_if_not(self.item1 > item2)
        return self
    def to_be_empty(self):
        """
        限定 item1 为 str 或 list
        """
        if isinstance(self.item1, str) or isinstance(self.item1, list):
            assert self.__reverse_result_if_not(len(self.item1) == 0)
        else:
            raise Exception("item1 is not str or list")
        return self
    def is_instance_of(self, class_type: type):
        assert self.__reverse_result_if_not(isinstance(self.item1, class_type))
        return self
if __name__ == "__main__":
    Expect("AAA").to_equals("AAA")
    Expect("AAA").not_.to_equals("BBB")

在 API 自动化项目中使用

base_request.py

你的接口请求类

  @allure.step("断言")
  def asserts(self, expect_errcode=None, expect_message=None, expect_http_code=200):
      assert self.response.status_code == expect_http_code
      if expect_errcode is not None:
          assert expect_errcode == self.response.json().get("errCode")
          if expect_errcode != 200 and expect_message is not None:
              assert expect_message in self.response.json().get("message")
   @allure.step("断言")
   def expect(self, response_expr) -> Expect:
   	   results = jsonpath(self.response.json(), response_expr)
   	   if results:
              return Expect(results[0])