Mercurial > hg
view tests/hypothesishelpers.py @ 38893:23d582caae30
changegroup: capture revision delta in a data structure
The current changegroup generation code is tightly coupled to
the revlog API. This tight coupling makes it difficult to implement
alternate storage backends without requiring a large surface area
of the revlog API to be exposed. This is not desirable.
In order to support changegroup generation with non-revlog storage,
we'll need to abstract the concept of delta generation.
This commit is the first step down that road. We introduce a
data structure for representing a delta in a changegroup.
The API still leaves a lot to be desired. But at least we now
have separation between data and actions performed on it.
As part of this, we tweak behavior slightly: we no longer
concatenate the delta prefix with the metadata header. Instead,
we track and emit the prefix as a separate chunk. This shouldn't
have any meaningful impact since all the chunks just get sent to
the wire, the compressor, etc.
Because we're introducing a new object, this does add some
overhead to changegroup execution. `hg perfchangegroupchangelog`
on my clone of the Mercurial repo (~40,000 visible revisions in
the changelog) slows down a bit:
! wall 1.268600 comb 1.270000 user 1.270000 sys 0.000000 (best of 8)
! wall 1.419479 comb 1.410000 user 1.410000 sys 0.000000 (best of 8)
With for `hg bundle -t none-v2 -a /dev/null`:
before: real 6.610 secs (user 6.460+0.000 sys 0.140+0.000)
after: real 7.210 secs (user 7.060+0.000 sys 0.140+0.000)
I plan to claw back this regression in future commits. And I may
even do away with this data structure once the refactor is complete.
For now, it makes things easier to comprehend.
Differential Revision: https://phab.mercurial-scm.org/D4075
author | Gregory Szorc <gregory.szorc@gmail.com> |
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date | Fri, 03 Aug 2018 10:05:26 -0700 |
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()