tests/printrevset.py

errors: make exit codes class variables instead

Kyle pointed out to me that we can simply make the exit codes class
variables. Python provides some magic for making them accessible as
instance variables.

This also makes it easier to let subclasses of existing errors
override the exit codes by letting them simply define their own values
as class variables. That means that there's no need to pass them into
the superclass's constructor arguments, so the superclass doesn't need
to expose the them as arguments. (Making a subclass set a different
exit code for a subclass of `StorageError` was actually the goal with
my recent series.)

Differential Revision: https://phab.mercurial-scm.org/D10758

from __future__ import absolute_import
from mercurial.thirdparty import attr
from mercurial import (
    cmdutil,
    commands,
    extensions,
    logcmdutil,
    revsetlang,
    smartset,
)

from mercurial.utils import stringutil


def logrevset(repo, wopts):
    revs = logcmdutil._initialrevs(repo, wopts)
    if not revs:
        return None
    match, pats, slowpath = logcmdutil._makematcher(repo, revs, wopts)
    wopts = attr.evolve(wopts, pats=pats)
    return logcmdutil._makerevset(repo, wopts, slowpath)


def uisetup(ui):
    def printrevset(orig, repo, wopts):
        revs, filematcher = orig(repo, wopts)
        if wopts.opts.get(b'print_revset'):
            expr = logrevset(repo, wopts)
            if expr:
                tree = revsetlang.parse(expr)
                tree = revsetlang.analyze(tree)
            else:
                tree = []
            ui = repo.ui
            ui.write(b'%s\n' % stringutil.pprint(wopts.opts.get(b'rev', [])))
            ui.write(revsetlang.prettyformat(tree) + b'\n')
            ui.write(stringutil.prettyrepr(revs) + b'\n')
            revs = smartset.baseset()  # display no revisions
        return revs, filematcher

    extensions.wrapfunction(logcmdutil, 'getrevs', printrevset)
    aliases, entry = cmdutil.findcmd(b'log', commands.table)
    entry[1].append(
        (
            b'',
            b'print-revset',
            False,
            b'print generated revset and exit (DEPRECATED)',
        )
    )