hgext/bookflow.py

extdiff: refactor logic which does diff of patches

The current extdiff code is hard to understand on first look. Took me few hours
to grasp the code. Before adding more things, decided to do some refactoring.

Differential Revision: https://phab.mercurial-scm.org/D8686

"""implements bookmark-based branching (EXPERIMENTAL)

 - Disables creation of new branches (config: enable_branches=False).
 - Requires an active bookmark on commit (config: require_bookmark=True).
 - Doesn't move the active bookmark on update, only on commit.
 - Requires '--rev' for moving an existing bookmark.
 - Protects special bookmarks (config: protect=@).

 flow related commands

    :hg book NAME: create a new bookmark
    :hg book NAME -r REV: move bookmark to revision (fast-forward)
    :hg up|co NAME: switch to bookmark
    :hg push -B .: push active bookmark
"""
from __future__ import absolute_import

from mercurial.i18n import _
from mercurial import (
    bookmarks,
    commands,
    error,
    extensions,
    registrar,
)

MY_NAME = b'bookflow'

configtable = {}
configitem = registrar.configitem(configtable)

configitem(MY_NAME, b'protect', [b'@'])
configitem(MY_NAME, b'require-bookmark', True)
configitem(MY_NAME, b'enable-branches', False)

cmdtable = {}
command = registrar.command(cmdtable)


def commit_hook(ui, repo, **kwargs):
    active = repo._bookmarks.active
    if active:
        if active in ui.configlist(MY_NAME, b'protect'):
            raise error.Abort(
                _(b'cannot commit, bookmark %s is protected') % active
            )
        if not cwd_at_bookmark(repo, active):
            raise error.Abort(
                _(
                    b'cannot commit, working directory out of sync with active bookmark'
                ),
                hint=_(b"run 'hg up %s'") % active,
            )
    elif ui.configbool(MY_NAME, b'require-bookmark', True):
        raise error.Abort(_(b'cannot commit without an active bookmark'))
    return 0


def bookmarks_update(orig, repo, parents, node):
    if len(parents) == 2:
        # called during commit
        return orig(repo, parents, node)
    else:
        # called during update
        return False


def bookmarks_addbookmarks(
    orig, repo, tr, names, rev=None, force=False, inactive=False
):
    if not rev:
        marks = repo._bookmarks
        for name in names:
            if name in marks:
                raise error.Abort(
                    _(
                        b"bookmark %s already exists, to move use the --rev option"
                    )
                    % name
                )
    return orig(repo, tr, names, rev, force, inactive)


def commands_commit(orig, ui, repo, *args, **opts):
    commit_hook(ui, repo)
    return orig(ui, repo, *args, **opts)


def commands_pull(orig, ui, repo, *args, **opts):
    rc = orig(ui, repo, *args, **opts)
    active = repo._bookmarks.active
    if active and not cwd_at_bookmark(repo, active):
        ui.warn(
            _(
                b"working directory out of sync with active bookmark, run "
                b"'hg up %s'"
            )
            % active
        )
    return rc


def commands_branch(orig, ui, repo, label=None, **opts):
    if label and not opts.get('clean') and not opts.get('rev'):
        raise error.Abort(
            _(
                b"creating named branches is disabled and you should use bookmarks"
            ),
            hint=b"see 'hg help bookflow'",
        )
    return orig(ui, repo, label, **opts)


def cwd_at_bookmark(repo, mark):
    mark_id = repo._bookmarks[mark]
    cur_id = repo.lookup(b'.')
    return cur_id == mark_id


def uisetup(ui):
    extensions.wrapfunction(bookmarks, b'update', bookmarks_update)
    extensions.wrapfunction(bookmarks, b'addbookmarks', bookmarks_addbookmarks)
    extensions.wrapcommand(commands.table, b'commit', commands_commit)
    extensions.wrapcommand(commands.table, b'pull', commands_pull)
    if not ui.configbool(MY_NAME, b'enable-branches'):
        extensions.wrapcommand(commands.table, b'branch', commands_branch)