view tests/hypothesishelpers.py @ 42415:c767e655ffda

narrow: use narrow_widen wireproto command to widen in case of ellipses

Few releases ago, we introduce narrow_widen wireproto command to be used to widen
narrow repositories. Before this patch, that was used in non-ellipses cases
only. In ellipses cases, we still do exchange.pull() which can pull more data
than required.

After this patch, the client will first check whether server supports doing
ellipses widening using wireproto command or not by checking server's wireproto
capability. If the server is upto date and support latest ellipses capability,
we call the wireproto command. Otherwise we fallback to exchange.pull() like
before.

The compat code make sure that things works even if one of the client or server
is old. The initial version of this patch does not had this compat code. It's
added to help Google release things smoothly internally. I plan to drop the
compat code before the upcoming major release.

Due to change to wireproto command, the code looks a bit dirty, next patches
will clean that up.

Differential Revision: https://phab.mercurial-scm.org/D6436

# 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()