Mercurial > hg
view tests/hypothesishelpers.py @ 35190:bd8875b6473c
run-tests: mechanism to report exceptions during test execution
Sometimes when running tests you introduce a ton of exceptions.
The most extreme example of this is running Mercurial with Python 3,
which currently spews thousands of exceptions when running the test
harness.
This commit adds an opt-in feature to run-tests.py to aggregate
exceptions encountered by `hg` when running tests.
When --exceptions is used, the test harness enables the
"logexceptions" extension in the test environment. This extension
wraps the Mercurial function to handle exceptions and writes
information about the exception to a random filename in a directory
defined by the test harness via an environment variable. At the
end of the test harness, these files are parsed, aggregated, and
a list of all unique Mercurial frames triggering exceptions is
printed in order of frequency.
This feature is intended to aid Python 3 development. I've only
really tested it on Python 3. There is no shortage of improvements
that could be made. e.g. we could write a separate file containing
the exception report - maybe even an HTML report. We also don't
capture which tests demonstrate the exceptions, so there's no turnkey
way to test whether a code change made an exception disappear.
Perfect is the enemy of good. I think the current patch is useful
enough to land. Whoever uses it can send patches to imprve its
usefulness.
Differential Revision: https://phab.mercurial-scm.org/D1477
author | Gregory Szorc <gregory.szorc@gmail.com> |
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date | Mon, 20 Nov 2017 23:02:32 -0800 |
parents | 8699c89f3ae9 |
children | 2372284d9457 |
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# Helper module to use the Hypothesis tool in tests # # Copyright 2015 David R. MacIver # # For details see http://hypothesis.readthedocs.org from __future__ import absolute_import, print_function import os import sys import traceback try: # hypothesis 2.x from hypothesis.configuration import set_hypothesis_home_dir from hypothesis import settings except ImportError: # hypothesis 1.x from hypothesis.settings import set_hypothesis_home_dir from hypothesis import Settings as settings import hypothesis.strategies as st from hypothesis import given # hypothesis store data regarding generate example and code set_hypothesis_home_dir(os.path.join( os.getenv('TESTTMP'), ".hypothesis" )) def check(*args, **kwargs): """decorator to make a function a hypothesis test Decorated function are run immediately (to be used doctest style)""" def accept(f): # Workaround for https://github.com/DRMacIver/hypothesis/issues/206 # Fixed in version 1.13 (released 2015 october 29th) f.__module__ = '__anon__' try: with settings(max_examples=2000): given(*args, **kwargs)(f)() except Exception: traceback.print_exc(file=sys.stdout) sys.exit(1) return accept def roundtrips(data, decode, encode): """helper to tests function that must do proper encode/decode roundtripping """ @given(data) def testroundtrips(value): encoded = encode(value) decoded = decode(encoded) if decoded != value: raise ValueError( "Round trip failed: %s(%r) -> %s(%r) -> %r" % ( encode.__name__, value, decode.__name__, encoded, decoded )) try: testroundtrips() except Exception: # heredoc swallow traceback, we work around it traceback.print_exc(file=sys.stdout) raise print("Round trip OK") # strategy for generating bytestring that might be an issue for Mercurial bytestrings = ( st.builds(lambda s, e: s.encode(e), st.text(), st.sampled_from([ 'utf-8', 'utf-16', ]))) | st.binary()