mercurial/txnutil.py

tests: don't be as verbose in wireprotov2 tests

I don't think that printing low-level I/O and frames is beneficial to
testing command-level functionality. Protocol-level testing, yes. But
command-level functionality shouldn't care about low-level details in
most cases. This output makes tests more verbose and harder to read.
It also makes them harder to maintain, as you need to glob over various
dynamic width fields.

Let's remove these low-level details from many of the wireprotov2
tests.

Differential Revision: https://phab.mercurial-scm.org/D4861

# txnutil.py - transaction related utilities
#
#  Copyright FUJIWARA Katsunori <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import errno

from . import (
    encoding,
)

def mayhavepending(root):
    '''return whether 'root' may have pending changes, which are
    visible to this process.
    '''
    return root == encoding.environ.get('HG_PENDING')

def trypending(root, vfs, filename, **kwargs):
    '''Open  file to be read according to HG_PENDING environment variable

    This opens '.pending' of specified 'filename' only when HG_PENDING
    is equal to 'root'.

    This returns '(fp, is_pending_opened)' tuple.
    '''
    if mayhavepending(root):
        try:
            return (vfs('%s.pending' % filename, **kwargs), True)
        except IOError as inst:
            if inst.errno != errno.ENOENT:
                raise
    return (vfs(filename, **kwargs), False)