我遇到了一个我无法理解的 pytest 参数化 fixture 的奇怪行为。
鉴于此 sample.py :
import pytest
import requests
import conftest
@pytest.mark.parametrize('handler_class', [conftest.Child])
def test_simple(my_fixture):
try:
requests.get("http://localhost:8000")
except:
pass
以及同一目录中的以下 conftest.py :
class Base(http.server.SimpleHTTPRequestHandler):
def __init__(self, request, client_address, server):
super().__init__(request, client_address, server)
self.value = 0
def do_GET(self):
print(self.value) # AttributeError: 'Child' object has no attribute 'value'
self.send_error(500)
class Child(Base):
def __init__(self, request, client_address, server):
super().__init__(request, client_address, server)
self.value = 1
@pytest.fixture
def my_fixture(handler_class):
handler = handler_class
httpd = http.server.HTTPServer(('', 8000), handler)
http_thread = threading.Thread(target=httpd.serve_forever)
http_thread.start()
yield
httpd.shutdown()
如果你跑
pytest -s sample.py
有一个异常(exception),“AttributeError: 'Child' object has no attribute 'value'” 为什么?类 Base 和 Child 都有一个 value 属性。
最佳答案
我的建议是该行 print(self.value)
在行之前到达 self.value = 0
在其他线程中,这就是发生此类错误的原因。你需要像这样重构你的代码:
class Base(http.server.SimpleHTTPRequestHandler):
def __init__(self, request, client_address, server, value=0):
self.value = value
super().__init__(request, client_address, server)
def do_GET(self):
print(self.value) # 1 when doing pytest -s sample.py
self.send_error(500)
class Child(Base):
def __init__(self, request, client_address, server):
super().__init__(request, client_address, server, value=1)
关于python - 具有继承性的 pytest 参数化 fixture - 子类没有属性,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/54790561/