view tests/hypothesishelpers.py @ 44412:edc8504bc26b

exchange: turn on option that makes concurrent pushes work better

The motivation is simply to make hg work better out of the box.

This is a slight backwards compatibility break, because client
extensions could have assumed that the list of heads the client sees
during discovery will be the list of heads during the entirety of the
push. It seems unlikely to matter, and not worth mentioning.

There's a fair amount of diff in tests, but this is just due to
sending a few more bytes on the wire, except for test-acl.t.
The extra "invalid branch cache" lines in test-acl.t don't seem to
indicate a problem: the branchcache now get computed during the bundle
application (because of the check:updated-heads bundle part), but
doesn't get rolled back when transactions rollback, thus causing a
message in the next operation computing the branch cache. Before this
change, I assume the branchcache was only computed on transaction
commit, so not computed at all when the transactions roll back, thus
no messages.

Differential Revision: https://phab.mercurial-scm.org/D8202

# 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()