view tests/hypothesishelpers.py @ 40623:7c5a922be068

tests: document a known failing interaction between narrow and lfs

This is one of the two remaining aborts I found looking into issue5794.  I've
got no idea what's wrong with the hook, since the changes there fixed the other
two problems noted in that bug report.  It seems like it might go away when the
narrow issue is fixed, but let's make sure this doesn't get lost.

The stacktrace for the hook seems to indicate that the missing file *is* in ctx:

  remote: Traceback (most recent call last):
  remote:   File "c:\Users\Matt\projects\hg\hgext\lfs\__init__.py", line 253, in checkrequireslfs
  remote:     if any(f in ctx and match(f) and ctx[f].islfs() for f in ctx.files()):
  remote:   File "c:\Users\Matt\projects\hg\hgext\lfs\__init__.py", line 253, in <genexpr>
  remote:     if any(f in ctx and match(f) and ctx[f].islfs() for f in ctx.files()):
  remote:   File "c:\Users\Matt\projects\hg\hgext\lfs\wrapper.py", line 191, in filectxislfs
  remote:     return _islfs(self.filelog(), self.filenode())
  remote:   File "c:\Users\Matt\projects\hg\mercurial\context.py", line 631, in filenode
  remote:     return self._filenode
  remote:   File "c:\Users\Matt\projects\hg\mercurial\util.py", line 1528, in __get__
  remote:     result = self.func(obj)
  remote:   File "c:\Users\Matt\projects\hg\mercurial\context.py", line 579, in _filenode
  remote:     return self._filelog.lookup(self._fileid)
  remote:   File "c:\Users\Matt\projects\hg\mercurial\filelog.py", line 68, in lookup
  remote:     self._revlog.indexfile)
  remote:   File "c:\Users\Matt\projects\hg\mercurial\utils\storageutil.py", line 218, in fileidlookup
  remote:     raise error.LookupError(fileid, identifier, _('no match found'))
  remote: LookupError: data/inside2/f.i@f59b4e021835: no match found

# 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()