Coverage for local/lib/python2.7/site-packages/sage/misc/sage_unittest.py : 76%
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r""" Unit testing for Sage objects """
#***************************************************************************** # Copyright (C) 2009 Nicolas M. Thiery <nthiery at users.sf.net> # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 2 of the License, or # (at your option) any later version. # http://www.gnu.org/licenses/ #*****************************************************************************
import unittest import sys import traceback import random
class TestSuite(object): """ Test suites for Sage objects.
EXAMPLES::
sage: TestSuite(ZZ).run()
No output means that all tests passed. Which tests? In practice this calls all the methods ``._test_*`` of this object, in alphabetic order::
sage: TestSuite(1).run(verbose = True) running ._test_category() . . . pass running ._test_eq() . . . pass running ._test_new() . . . pass running ._test_nonzero_equal() . . . pass running ._test_not_implemented_methods() . . . pass running ._test_pickling() . . . pass
Those methods are typically implemented by abstract super classes, in particular via categories, in order to enforce standard behavior and API, or provide mathematical sanity checks. For example if ``self`` is in the category of finite semigroups, this checks that the multiplication is associative (at least on some elements)::
sage: S = FiniteSemigroups().example(alphabet = ('a', 'b')) sage: TestSuite(S).run(verbose = True) running ._test_an_element() . . . pass running ._test_associativity() . . . pass running ._test_cardinality() . . . pass running ._test_category() . . . pass running ._test_elements() . . . Running the test suite of self.an_element() running ._test_category() . . . pass running ._test_eq() . . . pass running ._test_new() . . . pass running ._test_not_implemented_methods() . . . pass running ._test_pickling() . . . pass pass running ._test_elements_eq_reflexive() . . . pass running ._test_elements_eq_symmetric() . . . pass running ._test_elements_eq_transitive() . . . pass running ._test_elements_neq() . . . pass running ._test_enumerated_set_contains() . . . pass running ._test_enumerated_set_iter_cardinality() . . . pass running ._test_enumerated_set_iter_list() . . . pass running ._test_eq() . . . pass running ._test_new() . . . pass running ._test_not_implemented_methods() . . . pass running ._test_pickling() . . . pass running ._test_some_elements() . . . pass
The different test methods can be called independently::
sage: S._test_associativity()
Debugging tip: in case of failure of some test, use ``%pdb on`` to turn on automatic debugging on error. Run the failing test independently: the debugger will stop right where the first assertion fails. Then, introspection can be used to analyse what exactly the problem is. See also the ``catch = False`` option to :meth:`.run`.
When meaningful, one can further customize on which elements the tests are run. Here, we use it to *prove* that the multiplication is indeed associative, by running the test on all the elements::
sage: S._test_associativity(elements = S)
Adding a new test boils down to adding a new method in the class of the object or any super class (e.g. in a category). This method should use the utility :meth:`._tester` to handle standard options and report test failures. See the code of :meth:`._test_an_element` for an example. Note: Python's testunit convention is to look for methods called ``.test*``; we use instead ``._test_*`` so as not to pollute the object's interface.
Eventually, every implementation of a :class:`SageObject` should run a :class:`TestSuite` on one of its instances in its doctest (replacing the current ``loads(dumps(x))`` tests).
Finally, running ``TestSuite`` on a standard Python object does some basic sanity checks::
sage: TestSuite(int(1)).run(verbose = True) running ._test_new() . . . pass running ._test_pickling() . . . pass
TODO:
- Allow for customized behavior in case of failing assertion (warning, error, statistic accounting). This involves reimplementing the methods fail / failIf / ... of unittest.TestCase in InstanceTester
- Don't catch the exceptions if ``TestSuite(..).run()`` is called under the debugger, or with ``%pdb`` on (how to detect this? see ``get_ipython()``, ``IPython.Magic.shell.call_pdb``, ...) In the mean time, see the ``catch=False`` option.
- Run the tests according to the inheritance order, from most generic to most specific, rather than alphabetically. Then, the first failure will be the most relevant, the others being usually consequences.
- Improve integration with doctests (statistics on failing/passing tests)
- Add proper support for nested testsuites.
- Integration with unittest: Make TestSuite inherit from unittest.TestSuite? Make ``.run(...)`` accept a result object
- Add some standard option ``proof = True``, asking for the test method to choose appropriately the elements so as to prove the desired property. The test method may assume that a parent implements properly all the super categories. For example, the ``_test_commutative`` method of the category ``CommutativeSemigroups()`` may just check that the provided generators commute, implicitly assuming that generators indeed generate the semigroup (as required by ``Semigroups()``). """
def __init__(self, instance): """ TESTS::
sage: TestSuite(ZZ) Test suite for Integer Ring """
def __repr__(self): """ TESTS::
sage: TestSuite(ZZ) Test suite for Integer Ring """
def run(self, category = None, skip = [], catch = True, raise_on_failure = False, **options): """ Run all the tests from this test suite:
INPUT:
- ``category`` - a category; reserved for future use - ``skip`` - a string or list (or iterable) of strings - ``raise_on_failure`` - a boolean (default: False) - ``catch`` - a boolean (default: True)
All other options are passed down to the individual tests.
EXAMPLES::
sage: TestSuite(ZZ).run()
We now use the ``verbose`` option::
sage: TestSuite(1).run(verbose = True) running ._test_category() . . . pass running ._test_eq() . . . pass running ._test_new() . . . pass running ._test_nonzero_equal() . . . pass running ._test_not_implemented_methods() . . . pass running ._test_pickling() . . . pass
Some tests may be skipped using the ``skip`` option::
sage: TestSuite(1).run(verbose = True, skip ="_test_pickling") running ._test_category() . . . pass running ._test_eq() . . . pass running ._test_new() . . . pass running ._test_nonzero_equal() . . . pass running ._test_not_implemented_methods() . . . pass sage: TestSuite(1).run(verbose = True, skip =["_test_pickling", "_test_category"]) running ._test_eq() . . . pass running ._test_new() . . . pass running ._test_nonzero_equal() . . . pass running ._test_not_implemented_methods() . . . pass
We now show (and test) some standard error reports::
sage: class Blah(SageObject): ....: def _test_a(self, tester): pass ....: def _test_b(self, tester): tester.fail() ....: def _test_c(self, tester): pass ....: def _test_d(self, tester): tester.fail()
sage: TestSuite(Blah()).run() Failure in _test_b: Traceback (most recent call last): ... AssertionError: None ------------------------------------------------------------ Failure in _test_d: Traceback (most recent call last): ... AssertionError: None ------------------------------------------------------------ Failure in _test_pickling: Traceback (most recent call last): ... PicklingError: Can't pickle <class '__main__.Blah'>: attribute lookup __main__.Blah failed ------------------------------------------------------------ The following tests failed: _test_b, _test_d, _test_pickling
sage: TestSuite(Blah()).run(verbose = True) running ._test_a() . . . pass running ._test_b() . . . fail Traceback (most recent call last): ... AssertionError: None ------------------------------------------------------------ running ._test_c() . . . pass running ._test_category() . . . pass running ._test_d() . . . fail Traceback (most recent call last): ... AssertionError: None ------------------------------------------------------------ running ._test_new() . . . pass running ._test_not_implemented_methods() . . . pass running ._test_pickling() . . . fail Traceback (most recent call last): ... PicklingError: Can't pickle <class '__main__.Blah'>: attribute lookup __main__.Blah failed ------------------------------------------------------------ The following tests failed: _test_b, _test_d, _test_pickling
File "/opt/sage/local/lib/python/site-packages/sage/misc/sage_unittest.py", line 183, in run test_method(tester = tester)
The ``catch=False`` option prevents ``TestSuite`` from catching exceptions::
sage: TestSuite(Blah()).run(catch=False) Traceback (most recent call last): ... File ..., in _test_b def _test_b(self, tester): tester.fail() ... AssertionError: None
In conjunction with ``%pdb on``, this allows for the debugger to jump directly to the first failure location. """ else:
# The class of exceptions that will be caught and reported; # other exceptions will get through. None catches nothing.
# TODO: improve pretty printing # could use the doc string of the test method? # The failure occured in a nested testsuite # which has already reported the details of # that failure else: else:
class TestSuiteFailure(AssertionError): pass
def instance_tester(instance, tester = None, **options): """ Returns a gadget attached to ``instance`` providing testing utilities.
EXAMPLES::
sage: from sage.misc.sage_unittest import instance_tester sage: tester = instance_tester(ZZ)
sage: tester.assertTrue(1 == 1) sage: tester.assertTrue(1 == 0) Traceback (most recent call last): ... AssertionError: False is not true sage: tester.assertTrue(1 == 0, "this is expected to fail") Traceback (most recent call last): ... AssertionError: this is expected to fail
sage: tester.assertEqual(1, 1) sage: tester.assertEqual(1, 0) Traceback (most recent call last): ... AssertionError: 1 != 0
The available assertion testing facilities are the same as in :class:`unittest.TestCase` [UNITTEST]_, which see (actually, by a slight abuse, tester is currently an instance of this class).
TESTS::
sage: instance_tester(ZZ, tester = tester) is tester True """ else:
class InstanceTester(unittest.TestCase): """ A gadget attached to an instance providing it with testing utilities.
EXAMPLES::
sage: from sage.misc.sage_unittest import InstanceTester sage: InstanceTester(instance = ZZ, verbose = True, elements = [1,2,3]) Testing utilities for Integer Ring
This is used by ``SageObject._tester``, which see::
sage: QQ._tester() Testing utilities for Rational Field """
def __init__(self, instance, elements = None, verbose = False, prefix = "", max_runs = 4096, max_samples = None, **options): """ A gadget attached to an instance providing it with testing utilities.
EXAMPLES::
sage: from sage.misc.sage_unittest import InstanceTester sage: InstanceTester(instance = ZZ, verbose = True, elements = [1,2,3]) Testing utilities for Integer Ring
This is used by ``SageObject._tester``, for example::
sage: QQ._tester() Testing utilities for Rational Field """
def runTest(self): """ Trivial implementation of :meth:`unittest.TestCase.runTest` to please the super class :class:`TestCase`. That's the price to pay for abusively inheriting from it.
EXAMPLES::
sage: from sage.misc.sage_unittest import InstanceTester sage: tester = InstanceTester(ZZ, verbose = True) sage: tester.runTest() """
def info(self, message, newline = True): """ Displays user information
EXAMPLES::
sage: from sage.misc.sage_unittest import InstanceTester sage: tester = InstanceTester(ZZ, verbose = True)
sage: tester.info("hello"); tester.info("world") hello world
sage: tester = InstanceTester(ZZ, verbose = False) sage: tester.info("hello"); tester.info("world")
sage: tester = InstanceTester(ZZ, verbose = True) sage: tester.info("hello", newline = False); tester.info(" world") hello world """ else:
def __repr__(self): """ EXAMPLES::
sage: from sage.misc.sage_unittest import InstanceTester sage: InstanceTester(ZZ, verbose = True) Testing utilities for Integer Ring
"""
def some_elements(self, S=None, repeat=None): """ Returns a list (or iterable) of elements of the instance on which the tests should be run. This is only meaningful for container objects like parents.
INPUT:
- ``S`` -- a set of elements to select from. By default this will use the elements passed to this tester at creation time, or the result of :meth:`.some_elements` if no elements were specified.
- ``repeat`` -- integer (default: None). If given, instead returns a list of tuples of length ``repeat`` from ``S``.
OUTPUT:
A list of at most ``self._max_runs`` elements of ``S^r``, or a sample of at most ``self._max_samples`` if that is not ``None``.
EXAMPLES:
By default, this calls :meth:`.some_elements` on the instance::
sage: from sage.misc.sage_unittest import InstanceTester sage: class MyParent(Parent): ....: def some_elements(self): ....: return [1,2,3,4,5] ... sage: tester = InstanceTester(MyParent()) sage: list(tester.some_elements()) [1, 2, 3, 4, 5]
sage: tester = InstanceTester(MyParent(), max_runs=3) sage: list(tester.some_elements()) [1, 2, 3]
sage: tester = InstanceTester(MyParent(), max_runs=7) sage: list(tester.some_elements()) [1, 2, 3, 4, 5]
sage: tester = InstanceTester(MyParent(), elements=[1,3,5]) sage: list(tester.some_elements()) [1, 3, 5]
sage: tester = InstanceTester(MyParent(), elements=[1,3,5], max_runs=2) sage: list(tester.some_elements()) [1, 3]
sage: tester = InstanceTester(FiniteEnumeratedSet(['a','b','c','d']), max_runs=3) sage: tester.some_elements() ['a', 'b', 'c']
sage: tester = InstanceTester(FiniteEnumeratedSet([])) sage: list(tester.some_elements()) []
sage: tester = InstanceTester(ZZ) sage: ZZ.some_elements() # yikes, shamelessly trivial ... <generator object _some_elements_from_iterator at 0x...> sage: list(tester.some_elements()) [0, 1, -1, 2, -2, ..., 49, -49, 50]
sage: tester = InstanceTester(ZZ, elements = ZZ, max_runs=5) sage: list(tester.some_elements()) [0, 1, -1, 2, -2]
sage: tester = InstanceTester(ZZ, elements = srange(100), max_runs=5) sage: list(tester.some_elements()) [0, 1, 2, 3, 4]
sage: tester = InstanceTester(ZZ, elements = srange(3), max_runs=5) sage: list(tester.some_elements()) [0, 1, 2]
The ``repeat`` keyword can give pairs or triples from ``S``::
sage: list(tester.some_elements(repeat=2)) [(0, 0), (0, 1), (0, 2), (1, 0), (1, 1)]
You can use ``max_samples`` to sample at random, instead of in order::
sage: tester = InstanceTester(ZZ, elements = srange(8), max_samples = 4) sage: list(tester.some_elements()) [0, 3, 7, 1] sage: list(tester.some_elements(repeat=2)) [(1, 4), (3, 1), (4, 5), (5, 0)]
Test for :trac:`15919`, :trac:`16244`::
sage: Z = IntegerModRing(25) # random.sample, which was used pre #16244, has a threshold at 21! sage: Z[1] # since #8389, indexed access is used for ring extensions Traceback (most recent call last): ... ValueError: variable name '1' does not start with a letter sage: tester = InstanceTester(Z, elements=Z, max_runs=5) sage: list(tester.some_elements()) [0, 1, 2, 3, 4]
sage: C = cartesian_product([Z]*4) sage: len(C) 390625 sage: tester = InstanceTester(C, elements = C, max_runs=4) sage: list(tester.some_elements()) [(0, 0, 0, 0), (0, 0, 0, 1), (0, 0, 0, 2), (0, 0, 0, 3)] """
class PythonObjectWithTests(object): """ Utility class for running basis tests on a plain Python object (that is not in SageObject). More test methods can be added here.
EXAMPLES::
sage: TestSuite("bla").run() """ def __init__(self, instance): """ EXAMPLES::
sage: from sage.misc.sage_unittest import PythonObjectWithTests sage: x = PythonObjectWithTests(int(1)); x <sage.misc.sage_unittest.PythonObjectWithTests object at ...> sage: TestSuite(x).run() """
def _test_pickling(self, **options): """ Checks that the instance in self can be pickled and unpickled properly.
EXAMPLES::
sage: from sage.misc.sage_unittest import PythonObjectWithTests sage: PythonObjectWithTests(int(1))._test_pickling()
.. SEEALSO::
:func:`dumps`, :func:`loads` """
def _test_new(self, **options): """ Check that ``cls.__new__(cls)`` does not crash Python, with ``cls`` either the tested instance (if it's a type) or the type of the instance.
It is perfectly legal for ``__new__`` to raise ordinary exceptions.
EXAMPLES::
sage: TestSuite(int(1)).run(verbose=True) running ._test_new() . . . pass running ._test_pickling() . . . pass sage: TestSuite(int).run(verbose=True) running ._test_new() . . . pass running ._test_pickling() . . . pass """ |