脓包

py.测试支持XFAIL/XPASS的技巧

sympy.testing.pytest.SKIP(reason)

类似 skip() ，但这是个装修工。

sympy.testing.pytest.nocache_fail(func)

虚拟装饰器，用于标记禁用缓存时失败的测试

sympy.testing.pytest.raises(expectedException, code=None)

测试 code 引发异常 expectedException .

code 可以是可调用的，例如lambda表达式或函数名。

如果 code 不给或不给， raises 将返回上下文管理器以在中使用 with 语句；然后要执行的代码来自 with .

raises() 如果callable引发预期的异常，则不执行任何操作，否则将引发AssertionError。

实例

>>> from sympy.testing.pytest import raises

>>> raises(ZeroDivisionError, lambda: 1/0)
<ExceptionInfo ZeroDivisionError(...)>
>>> raises(ZeroDivisionError, lambda: 1/2)
Traceback (most recent call last):
...
Failed: DID NOT RAISE

>>> with raises(ZeroDivisionError):
...     n = 1/0
>>> with raises(ZeroDivisionError):
...     n = 1/2
Traceback (most recent call last):
...
Failed: DID NOT RAISE

请注意，您不能通过 with raises ：

>>> with raises(ZeroDivisionError):
...     n = 1/0    # will execute and raise, aborting the ``with``
...     n = 9999/0 # never executed

这就是什么 with 假定管理器在第一个异常中处理异常：让异常在第一个异常中终止。

要测试多个语句，您需要一个单独的 with 每种：

>>> with raises(ZeroDivisionError):
...     n = 1/0    # will execute and raise
>>> with raises(ZeroDivisionError):
...     n = 9999/0 # will also execute and raise

sympy.testing.pytest.skip_under_pyodide(message)

Decorator to skip a test if running under pyodide.

sympy.testing.pytest.warns(warningcls, *, match='', test_stacklevel=True)

就像发出警告一样，但也会发出警告。

>>> from sympy.testing.pytest import warns
>>> import warnings

>>> with warns(UserWarning):
...     warnings.warn('deprecated', UserWarning, stacklevel=2)

>>> with warns(UserWarning):
...     pass
Traceback (most recent call last):
...
Failed: DID NOT WARN. No warnings of type UserWarning    was emitted. The list of emitted warnings is: [].

test_stacklevel makes it check that the stacklevel parameter to warn() is set so that the warning shows the user line of code (the code under the warns() context manager). Set this to False if this is ambiguous or if the context manager does not test the direct user code that emits the warning.

If the warning is a SymPyDeprecationWarning, this additionally tests that the active_deprecations_target is a real target in the active-deprecations.md file.

sympy.testing.pytest.warns_deprecated_sympy()

缩写为 warns(SymPyDeprecationWarning)

这是推荐的测试方法 SymPyDeprecationWarning 为SymPy中已弃用的功能发出。要测试其他警告，请使用 warns . 要在不声明发出警告的情况下抑制警告，请使用 ignore_warnings .

备注

warns_deprecated_sympy() is only intended for internal use in the SymPy test suite to test that a deprecation warning triggers properly. All other code in the SymPy codebase, including documentation examples, should not use deprecated behavior.

If you are a user of SymPy and you want to disable SymPyDeprecationWarnings, use warnings filters (see Silencing SymPy Deprecation Warnings).

>>> from sympy.testing.pytest import warns_deprecated_sympy
>>> from sympy.utilities.exceptions import sympy_deprecation_warning
>>> with warns_deprecated_sympy():
...     sympy_deprecation_warning("Don't use",
...        deprecated_since_version="1.0",
...        active_deprecations_target="active-deprecations")

>>> with warns_deprecated_sympy():
...     pass
Traceback (most recent call last):
...
Failed: DID NOT WARN. No warnings of type     SymPyDeprecationWarning was emitted. The list of emitted warnings is: [].

备注

Sometimes the stacklevel test will fail because the same warning is emitted multiple times. In this case, you can use sympy.utilities.exceptions.ignore_warnings() in the code to prevent the SymPyDeprecationWarning from being emitted again recursively. In rare cases it is impossible to have a consistent stacklevel for deprecation warnings because different ways of calling a function will produce different call stacks.. In those cases, use warns(SymPyDeprecationWarning) instead.

参见

sympy.utilities.exceptions.SymPyDeprecationWarning, sympy.utilities.exceptions.sympy_deprecation_warning, sympy.utilities.decorator.deprecated