Marking test functions with attributes

By using the pytest.mark helper you can easily set metadata on your test functions. There are some builtin markers, for example:

• skipif - skip a test function if a certain condition is met
• xfail - produce an “expected failure” outcome if a certain condition is met
• parametrize to perform multiple calls to the same test function.

It’s easy to create custom markers or to apply markers to whole test classes or modules. See Working with custom markers for examples which also serve as documentation.

API reference for mark related objects

class MarkGenerator

Factory for MarkDecorator objects - exposed as a pytest.mark singleton instance. Example:

import py
@pytest.mark.slowtest
def test_function():
   pass

will set a ‘slowtest’ MarkInfo object on the test_function object.

class MarkDecorator(name, args=None, kwargs=None)

A decorator for test functions and test classes. When applied it will create MarkInfo objects which may be retrieved by hooks as item keywords. MarkDecorator instances are often created like this:

mark1 = pytest.mark.NAME              # simple MarkDecorator
mark2 = pytest.mark.NAME(name1=value) # parametrized MarkDecorator

and can then be applied as decorators to test functions:

@mark2
def test_function():
    pass

When a MarkDecorator instance is called it does the following:

1. If called with a single class as its only positional argument and no additional keyword arguments, it attaches itself to the class so it gets applied automatically to all test cases found in that class.
2. If called with a single function as its only positional argument and no additional keyword arguments, it attaches a MarkInfo object to the function, containing all the arguments already stored internally in the MarkDecorator.
3. When called in any other case, it performs a ‘fake construction’ call, i.e. it returns a new MarkDecorator instance with the original MarkDecorator’s content updated with the arguments passed to this call.

Note: The rules above prevent MarkDecorator objects from storing only a single function or class reference as their positional argument with no additional keyword or positional arguments.

class MarkInfo(name, args, kwargs)

Marking object created by MarkDecorator instances.

name = None

name of attribute

args = None

positional argument list, empty if none specified

kwargs = None

keyword argument dictionary, empty if nothing specified

add(args, kwargs)

add a MarkInfo with the given args and kwargs.