在 Python 的单元测试中添加元数据到 TestCase

Question

我想将元数据添加到我编写的TestCase中的各个测试中，以使用Python的unittest框架。 元数据(实际上是字符串(需要通过测试过程进行并输出到 XML 文件。

除了保留测试之外，数据不会被 unittest 使用，也不会被我的测试代码使用。 (我有一个程序将在之后运行，打开XML文件，然后去寻找元数据/字符串(。

我以前使用过 NUnit，它允许使用 C# 属性来执行此操作。 具体来说，你可以把它放在一个类上面：

[Property("SmartArrayAOD", -3)]

然后稍后在 XML 输出中找到它。

是否可以将元数据附加到 Python 单元测试中的测试中？

Answer 1

转

储XML的简单方法

如果你只想在每次单元测试后将内容写入XML文件，只需向测试类添加一个tearDown方法(例如，如果你有, give it a(。

class MyTest(unittest.TestCase):
def tearDown(self):
dump_xml_however_you_do()
def test_whatever(self):
pass

一般方法

如果您想要一种通用方法来收集和跟踪所有测试中的元数据并在最后返回它，请尝试在测试类的__init__()中创建一个 astropy 表，并在tearDown()期间向其添加行，然后从 unittest 中提取对测试类初始化实例的引用，如下所示：

第 1 步：设置一个可重用的unittest.TestCase子类，这样我们就不必复制表处理

(将所有示例代码放在同一个文件中或复制导入(

"""
Demonstration of adding and retrieving meta data from python unittest tests
"""
import sys
import warnings
import unittest
import copy
import time
import astropy
import astropy.table
if sys.version_info < (3, 0):
from StringIO import StringIO
else:
from io import StringIO

class DemoTest(unittest.TestCase):
"""
Demonstrates setup of an astropy table in __init__, adding data to the table in tearDown
"""
def __init__(self, *args, **kwargs):
super(DemoTest, self).__init__(*args, **kwargs)
# Storing results in a list made it convenient to aggregate them later
self.results_tables = [astropy.table.Table(
names=('Name', 'Result', 'Time', 'Notes'),
dtype=('S50', 'S30', 'f8', 'S50'),
)]
self.results_tables[0]['Time'].unit = 'ms'
self.results_tables[0]['Time'].format = '0.3e'
self.test_timing_t0 = 0
self.test_timing_t1 = 0
def setUp(self):
self.test_timing_t0 = time.time()
def tearDown(self):
test_name = '.'.join(self.id().split('.')[-2:])
self.test_timing_t1 = time.time()
dt = self.test_timing_t1 - self.test_timing_t0
# Check for errors/failures in order to get state & description.  https://stackoverflow.com/a/39606065/6605826
if hasattr(self, '_outcome'):  # Python 3.4+
result = self.defaultTestResult()  # these 2 methods have no side effects
self._feedErrorsToResult(result, self._outcome.errors)
problem = result.errors or result.failures
state = not problem
if result.errors:
exc_note = result.errors[0][1].split('n')[-2]
elif result.failures:
exc_note = result.failures[0][1].split('n')[-2]
else:
exc_note = ''
else:  # Python 3.2 - 3.3 or 3.0 - 3.1 and 2.7
# result = getattr(self, '_outcomeForDoCleanups', self._resultForDoCleanups)  # DOESN'T WORK RELIABLY
# This is probably only good for python 2.x, meaning python 3.0, 3.1, 3.2, 3.3 are not supported.
exc_type, exc_value, exc_traceback = sys.exc_info()
state = exc_type is None
exc_note = '' if exc_value is None else '{}: {}'.format(exc_type.__name__, exc_value)
# Add a row to the results table
self.results_tables[0].add_row()
self.results_tables[0][-1]['Time'] = dt*1000  # Convert to ms
self.results_tables[0][-1]['Result'] = 'pass' if state else 'FAIL'
with warnings.catch_warnings():
warnings.filterwarnings('ignore', category=astropy.table.StringTruncateWarning)
self.results_tables[0][-1]['Name'] = test_name
self.results_tables[0][-1]['Notes'] = exc_note

步骤 2：设置提取元数据的测试管理器

def manage_tests(tests):
"""
Function for running tests and extracting meta data
:param tests: list of classes sub-classed from DemoTest
:return: (TextTestResult, Table, string)
result returned by unittest
astropy table
string: formatted version of the table
"""
table_sorting_columns = ['Result', 'Time']
# Build test suite
suite_list = []
for test in tests:
suite_list.append(unittest.TestLoader().loadTestsFromTestCase(test))
combo_suite = unittest.TestSuite(suite_list)
# Run tests
results = [unittest.TextTestRunner(verbosity=1, stream=StringIO(), failfast=False).run(combo_suite)]
# Catch test classes
suite_tests = []
for suite in suite_list:
suite_tests += suite._tests
# Collect results tables
results_tables = []
for suite_test in suite_tests:
if getattr(suite_test, 'results_tables', [None])[0] is not None:
results_tables += copy.copy(suite_test.results_tables)
# Process tables, if any
if len(results_tables):
a = []
while (len(a) == 0) and len(results_tables):
a = results_tables.pop(0)  # Skip empty tables, if any
results_table = a
for rt in results_tables:
if len(rt):
with warnings.catch_warnings():
warnings.filterwarnings('ignore', category=DeprecationWarning)
results_table = astropy.table.join(results_table, rt, join_type='outer')
try:
results_table = results_table.group_by(table_sorting_columns)
except Exception:
print('Error sorting test results table. Columns may not be in the preferred order.')
column_names = list(results_table.columns.keys())
alignments = ['<' if cn == 'Notes' else '>' for cn in column_names]
if len(results_table):
rtf = 'n'.join(results_table.pformat(align=alignments, max_width=-1))
exp_res = sum([result.testsRun - len(result.skipped) for result in results])
if len(results_table) != exp_res:
print('ERROR forming results table. Expected {} results, but table length is {}.'.format(
exp_res, len(results_table),
))
else:
rtf = None
else:
results_table = rtf = None
return results, results_table, rtf

步骤 3：用法示例

class FunTest1(DemoTest):
@staticmethod
def test_pass_1():
pass
@staticmethod
def test_fail_1():
assert False, 'Meant to fail for demo 1'

class FunTest2(DemoTest):
@staticmethod
def test_pass_2():
pass
@staticmethod
def test_fail_2():
assert False, 'Meant to fail for demo 2'

res, tab, form = manage_tests([FunTest1, FunTest2])
print(form)
print('')
for r in res:
print(r)
for error in r.errors:
print(error[0])
print(error[1])

示例结果：

$ python unittest_metadata.py 
Name         Result    Time                    Notes                  
ms                                            
-------------------- ------ --------- ----------------------------------------
FunTest2.test_fail_2   FAIL 5.412e-02 AssertionError: Meant to fail for demo 2
FunTest1.test_fail_1   FAIL 1.118e-01 AssertionError: Meant to fail for demo 1
FunTest2.test_pass_2   pass 6.199e-03                                         
FunTest1.test_pass_1   pass 6.914e-03                                         
<unittest.runner.TextTestResult run=4 errors=0 failures=2>

应该适用于python 2.7或3.7。您可以向表中添加所需的任何列。你可以在setUp、tearDown，甚至在测试期间向表格中添加参数和东西。

警告：

此解决方案访问受保护的属性_testsunittest.suite.TestSuite，这可能会产生意外结果。这个特定的实现在 python2.7 和 python3.7 中按预期工作，但套件构建和询问方式的微小变化很容易导致奇怪的事情发生。但是，我无法找到另一种方法来提取对 unittest 使用的类实例的引用。