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We make selective use of doctests__. In general they should provide
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*examples* within the API documentation which can incidentally be tested. We
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don't try to test every important case using doctests |--| regular Python
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tests are generally a better solution. That is, we just use doctests to
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make our documentation testable, rather than as a way to make tests.
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tests are generally a better solution. That is, we just use doctests to make
333
our documentation testable, rather than as a way to make tests. Be aware that
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doctests are not as well isolated as the unit tests, if you need more
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isolation, you're likely want to write unit tests anyway if only to get a
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better control of the test environment.
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Most of these are in ``bzrlib/doc/api``. More additions are welcome.
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__ http://docs.python.org/lib/module-doctest.html
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There is an `assertDoctestExampleMatches` method in
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`bzrlib.tests.TestCase` that allows you to match against doctest-style
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string templates (including ``...`` to skip sections) from regular Python
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``bzrlib/tests/script.py`` allows users to write tests in a syntax very close to a shell session,
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using a restricted and limited set of commands that should be enough to mimic
345
most of the behaviours.
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``bzrlib/tests/script.py`` allows users to write tests in a syntax very
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close to a shell session, using a restricted and limited set of commands
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that should be enough to mimic most of the behaviours.
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A script is a set of commands, each command is composed of:
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375
The execution stops as soon as an expected output or an expected error is not
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When no output is specified, any ouput from the command is accepted
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and execution continue.
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If output occurs and no output is expected, the execution stops and the
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test fails. If unexpected output occurs on the standard error, then
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execution stops and the test fails.
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If an error occurs and no expected error is specified, the execution stops.
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You can run files containing shell-like scripts with::
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$ bzr test-script <script>
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where ``<script>`` is the path to the file containing the shell-like script.
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The actual use of ScriptRunner within a TestCase looks something like
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def test_unshelve_keep(self):
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# some setup here
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script.run_script(self, '''
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$ bzr shelve --all -m Foo
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$ bzr shelve -q --all -m Foo
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$ bzr shelve --list
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$ bzr unshelve --keep
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$ bzr unshelve -q --keep
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$ bzr shelve --list
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You can also test commands that read user interaction::
472
def test_confirm_action(self):
473
"""You can write tests that demonstrate user confirmation"""
474
commands.builtin_command_registry.register(cmd_test_confirm)
475
self.addCleanup(commands.builtin_command_registry.remove, 'test-confirm')
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2>Really do it? [y/n]:
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To avoid having to specify "-q" for all commands whose output is
484
irrelevant, the run_script() method may be passed the keyword argument
485
``null_output_matches_anything=True``. For example::
487
def test_ignoring_null_output(self):
490
$ bzr ci -m 'first revision' --unchanged
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""", null_output_matches_anything=True)
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Import tariff tests
451
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-------------------
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745
_test_needs_features = [features.apport]
748
Testing deprecated code
749
-----------------------
751
When code is deprecated, it is still supported for some length of time,
752
usually until the next major version. The ``applyDeprecated`` helper
753
wraps calls to deprecated code to verify that it is correctly issuing the
754
deprecation warning, and also prevents the warnings from being printed
757
Typically patches that apply the ``@deprecated_function`` decorator should
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update the accompanying tests to use the ``applyDeprecated`` wrapper.
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``applyDeprecated`` is defined in ``bzrlib.tests.TestCase``. See the API
761
docs for more details.
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764
Testing exceptions and errors
703
765
-----------------------------
777
839
whether a test should be added for that particular implementation,
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840
or for all implementations of the interface.
780
The multiplication of tests for different implementations is normally
781
accomplished by overriding the ``load_tests`` function used to load tests
782
from a module. This function typically loads all the tests, then applies
783
a TestProviderAdapter to them, which generates a longer suite containing
784
all the test variations.
786
842
See also `Per-implementation tests`_ (above).
845
Test scenarios and variations
846
-----------------------------
792
848
Some utilities are provided for generating variations of tests. This can
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be used for per-implementation tests, or other cases where the same test
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854
values to which the test should be applied. The test suite should then
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also provide a list of scenarios in which to run the tests.
801
Typically ``multiply_tests_from_modules`` should be called from the test
802
module's ``load_tests`` function.
857
A single *scenario* is defined by a `(name, parameter_dict)` tuple. The
858
short string name is combined with the name of the test method to form the
859
test instance name. The parameter dict is merged into the instance's
864
load_tests = load_tests_apply_scenarios
866
class TestCheckout(TestCase):
868
scenarios = multiply_scenarios(
869
VaryByRepositoryFormat(),
873
The `load_tests` declaration or definition should be near the top of the
874
file so its effect can be seen.
905
977
Please see bzrlib.treebuilder for more details.
982
PreviewTrees are based on TreeTransforms. This means they can represent
983
virtually any state that a WorkingTree can have, including unversioned files.
984
They can be used to test the output of anything that produces TreeTransforms,
985
such as merge algorithms and revert. They can also be used to test anything
986
that takes arbitrary Trees as its input.
990
# Get an empty tree to base the transform on.
991
b = self.make_branch('.')
992
empty_tree = b.repository.revision_tree(_mod_revision.NULL_REVISION)
993
tt = TransformPreview(empty_tree)
994
self.addCleanup(tt.finalize)
995
# Empty trees don't have a root, so add it first.
996
root = tt.new_directory('', ROOT_PARENT, 'tree-root')
997
# Set the contents of a file.
998
tt.new_file('new-file', root, 'contents', 'file-id')
999
preview = tt.get_preview_tree()
1000
# Test the contents.
1001
self.assertEqual('contents', preview.get_file_text('file-id'))
1003
PreviewTrees can stack, with each tree falling back to the previous::
1005
tt2 = TransformPreview(preview)
1006
self.addCleanup(tt2.finalize)
1007
tt2.new_file('new-file2', tt2.root, 'contents2', 'file-id2')
1008
preview2 = tt2.get_preview_tree()
1009
self.assertEqual('contents', preview2.get_file_text('file-id'))
1010
self.assertEqual('contents2', preview2.get_file_text('file-id2'))
908
1013
Temporarily changing state
909
1014
~~~~~~~~~~~~~~~~~~~~~~~~~~
914
1019
self.overrideAttr(osutils, '_cached_user_encoding', 'latin-1')
1021
Temporarily changing environment variables
1022
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1024
If yout test needs to temporarily change some environment variable value
1025
(which generally means you want it restored at the end), you can use::
1027
self.overrideEnv('BZR_ENV_VAR', 'new_value')
1029
If you want to remove a variable from the environment, you should use the
1030
special ``None`` value::
1032
self.overrideEnv('PATH', None)
1034
If you add a new feature which depends on a new environment variable, make
1035
sure it behaves properly when this variable is not defined (if applicable) and
1036
if you need to enforce a specific default value, check the
1037
``TestCase._cleanEnvironment`` in ``bzrlib.tests.__init__.py`` which defines a
1038
proper set of values for all tests.
added
removed
doc/developers/testing.txt
