Source code for hypothesis.control

# coding=utf-8
#
# This file is part of Hypothesis, which may be found at
# https://github.com/HypothesisWorks/hypothesis-python
#
# Most of this work is copyright (C) 2013-2017 David R. MacIver
# (david@drmaciver.com), but it contains contributions by others. See
# CONTRIBUTING.rst for a full list of people who may hold copyright, and
# consult the git log if you need to determine who owns an individual
# contribution.
#
# This Source Code Form is subject to the terms of the Mozilla Public License,
# v. 2.0. If a copy of the MPL was not distributed with this file, You can
# obtain one at http://mozilla.org/MPL/2.0/.
#
# END HEADER

from __future__ import division, print_function, absolute_import

import traceback

from hypothesis.errors import CleanupFailed, InvalidArgument, \
    UnsatisfiedAssumption
from hypothesis.reporting import report
from hypothesis.utils.dynamicvariables import DynamicVariable


def reject():
    raise UnsatisfiedAssumption()


[docs]def assume(condition): """``assume()`` is like an :ref:`assert <python:assert>` that marks the example as bad, rather than failing the test. This allows you to specify properties that you *assume* will be true, and let Hypothesis try to avoid similar examples in future. """ if not condition: raise UnsatisfiedAssumption() return True
_current_build_context = DynamicVariable(None) def current_build_context(): context = _current_build_context.value if context is None: raise InvalidArgument( u'No build context registered') return context class BuildContext(object): def __init__(self, data, is_final=False, close_on_capture=True): self.data = data self.tasks = [] self.is_final = is_final self.close_on_capture = close_on_capture self.close_on_del = False self.notes = [] def __enter__(self): self.assign_variable = _current_build_context.with_value(self) self.assign_variable.__enter__() return self def __exit__(self, exc_type, exc_value, tb): self.assign_variable.__exit__(exc_type, exc_value, tb) if self.close() and exc_type is None: raise CleanupFailed() def local(self): return _current_build_context.with_value(self) def close(self): any_failed = False for task in self.tasks: try: task() except BaseException: any_failed = True report(traceback.format_exc()) return any_failed def cleanup(teardown): """Register a function to be called when the current test has finished executing. Any exceptions thrown in teardown will be printed but not rethrown. Inside a test this isn't very interesting, because you can just use a finally block, but note that you can use this inside map, flatmap, etc. in order to e.g. insist that a value is closed at the end. """ context = _current_build_context.value if context is None: raise InvalidArgument( u'Cannot register cleanup outside of build context') context.tasks.append(teardown) def note(value): """Report this value in the final execution.""" context = _current_build_context.value if context is None: raise InvalidArgument( 'Cannot make notes outside of a test') context.notes.append(value) if context.is_final: report(value)
[docs]def event(value): """Record an event that occurred this test. Statistics on number of test runs with each event will be reported at the end if you run Hypothesis in statistics reporting mode. Events should be strings or convertible to them. """ context = _current_build_context.value if context is None: raise InvalidArgument( 'Cannot make record events outside of a test') if context.data is not None: context.data.note_event(value)