如何仅在测试错误或失败时运行pytest fixture清理

Question

我想仅在测试不成功时保存pytest测试运行的日志文件，这可能是由于测试fixture设置中的错误或测试本身的失败。

我的方法是创建一个测试装置，复制yield之后的日志，但我不知道如何使其以测试结果为条件。

@pytest.fixture
def setup():
do_setup()
yield
do_teardown()
@pytest.fixture
def get_logs():
yield
if not test_success: # how to know this condition?
copy_log_files()
def test_run(get_logs, setup):
do_test_stuff()

Answer 1

使用pytest_runtest_makereport

用于创建_pytest.reports。对于每个设置，调用并拆卸测试项目的运行测试阶段。

并将其与_Result.get_result()一起使用，以在Node/Item中添加结果。

我们实际上可以按照中记录的相同步骤在fixture

中提供测试结果信息conftest.py

import pytest

@pytest.hookimpl(tryfirst=True, hookwrapper=True)
def pytest_runtest_makereport(item, call):
# execute all other hooks to obtain the report object
outcome = yield
rep = outcome.get_result()
# set a report attribute for each phase of a call, which can
# be "setup", "call", "teardown"
setattr(item, "rep_" + rep.when, rep)

test_module.py

import pytest

@pytest.fixture
def get_logs(request):
yield
if request.node.rep_call.failed:
# Add code here to cleanup failure scenario
print("executing test failed")
elif request.node.rep_call.passed:
# Add code here to cleanup success scenario
print("executing test success")

def test_run1(get_logs):
print("Test 1")
assert 1

def test_run2(get_logs):
print("Test 2")
assert 0

def test_run3(get_logs):
print("Test 3")
assert 1

def test_run4(get_logs):
print("Test 4")
assert 0

$ pytest -rP test_module.py
test_module.py .F.F                                                                           [100%]
============================================= FAILURES ==============================================
_____________________________________________ test_run2 _____________________________________________
get_logs = None
def test_run2(get_logs):
print("Test 2")
>       assert 0
E       assert 0
test_module.py:21: AssertionError
--------------------------------------- Captured stdout call ----------------------------------------
Test 2
------------------------------------- Captured stdout teardown --------------------------------------
executing test failed
_____________________________________________ test_run4 _____________________________________________
get_logs = None
def test_run4(get_logs):
print("Test 4")
>       assert 0
E       assert 0
test_module.py:31: AssertionError
--------------------------------------- Captured stdout call ----------------------------------------
Test 4
------------------------------------- Captured stdout teardown --------------------------------------
executing test failed
============================================== PASSES ===============================================
_____________________________________________ test_run1 _____________________________________________
--------------------------------------- Captured stdout call ----------------------------------------
Test 1
------------------------------------- Captured stdout teardown --------------------------------------
executing test success
_____________________________________________ test_run3 _____________________________________________
--------------------------------------- Captured stdout call ----------------------------------------
Test 3
------------------------------------- Captured stdout teardown --------------------------------------
executing test success
==================================== 2 failed, 2 passed in 0.11s ====================================