localrepo: create new function for instantiating a local repo object
Today, there is a single local repository class - localrepository. Its
__init__ is responsible for loading the .hg/requires file and taking
different actions depending on what is present.
In addition, extensions may define a "reposetup" function that
monkeypatches constructed repository instances, often by implementing
a derived type and changing the __class__ of the repo instance.
Work around alternate storage backends and partial clone has made it
clear to me that shoehorning all this logic into __init__ and operating
on an existing instance is too convoluted. For example, localrepository
assumes revlog storage and swapping in non-revlog storage requires
overriding e.g. file() to return something that isn't a revlog. I've
authored various patches that either:
a) teach various methods (like file()) about different states and
taking the appropriate code path at run-time
b) create methods/attributes/callables used for instantiating things
and populating these in __init__
"a" incurs run-time performance penalties and makes code more
complicated since various functions have a bunch of "if storage is X"
branches.
"b" makes localrepository quickly explode in complexity.
My plan for tackling this problem is to make the local repository type
more dynamic. Instead of a static localrepository class/type that
supports all of the local repository configurations (revlogs vs other,
revlogs with ellipsis, revlog v1 versus revlog v2, etc), we'll
dynamically construct a type providing the implementations that are
needed for the repository on disk, derived from the .hg/requires file
and configuration options. The constructed repository type will be
specialized and methods won't need to be taught about different
implementations nor overloaded.
We may also leverage this functionality for building types that don't
implement all attributes. For example, the "intents" feature allows
commands to declare that they are read only. By dynamically
constructing a repository type, we could return a repository instance
with no attributes related to mutating the repository. This could
include things like a "changelog" property implementation that doesn't
check whether it needs to invalidate the hidden revisions set on every
access.
This commit establishes a function for building a local repository
instance. Future commits will start moving functionality from
localrepository.__init__ to this function. Then we'll start dynamically
changing the returned type depending on options that are present.
This change may seem radical. But it should be fully compatible with
the reposetup() model - at least for now.
Differential Revision: https://phab.mercurial-scm.org/D4563
Test alignment of multibyte characters
$ HGENCODING=utf-8
$ export HGENCODING
$ hg init t
$ cd t
$ $PYTHON << EOF
> # (byte, width) = (6, 4)
> s = b"\xe7\x9f\xad\xe5\x90\x8d"
> # (byte, width) = (7, 7): odd width is good for alignment test
> m = b"MIDDLE_"
> # (byte, width) = (18, 12)
> l = b"\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d"
> f = open('s', 'wb'); f.write(s); f.close()
> f = open('m', 'wb'); f.write(m); f.close()
> f = open('l', 'wb'); f.write(l); f.close()
> # instant extension to show list of options
> f = open('showoptlist.py', 'wb'); f.write(b"""# encoding: utf-8
> from mercurial import registrar
> cmdtable = {}
> command = registrar.command(cmdtable)
>
> @command(b'showoptlist',
> [('s', 'opt1', '', 'short width' + ' %(s)s' * 8, '%(s)s'),
> ('m', 'opt2', '', 'middle width' + ' %(m)s' * 8, '%(m)s'),
> ('l', 'opt3', '', 'long width' + ' %(l)s' * 8, '%(l)s')],
> '')
> def showoptlist(ui, repo, *pats, **opts):
> '''dummy command to show option descriptions'''
> return 0
> """ % globals())
> f.close()
> EOF
$ S=`cat s`
$ M=`cat m`
$ L=`cat l`
alignment of option descriptions in help
$ cat <<EOF > .hg/hgrc
> [extensions]
> ja_ext = `pwd`/showoptlist.py
> EOF
check alignment of option descriptions in help
$ hg help showoptlist
hg showoptlist
dummy command to show option descriptions
options:
-s --opt1 \xe7\x9f\xad\xe5\x90\x8d short width \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d \xe7\x9f\xad\xe5\x90\x8d (esc)
-m --opt2 MIDDLE_ middle width MIDDLE_ MIDDLE_ MIDDLE_ MIDDLE_ MIDDLE_
MIDDLE_ MIDDLE_ MIDDLE_
-l --opt3 \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d long width \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d (esc)
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d (esc)
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d (esc)
(some details hidden, use --verbose to show complete help)
$ rm -f s; touch s
$ rm -f m; touch m
$ rm -f l; touch l
add files
$ cp s $S
$ hg add $S
$ cp m $M
$ hg add $M
$ cp l $L
$ hg add $L
commit(1)
$ echo 'first line(1)' >> s; cp s $S
$ echo 'first line(2)' >> m; cp m $M
$ echo 'first line(3)' >> l; cp l $L
$ hg commit -m 'first commit' -u $S
commit(2)
$ echo 'second line(1)' >> s; cp s $S
$ echo 'second line(2)' >> m; cp m $M
$ echo 'second line(3)' >> l; cp l $L
$ hg commit -m 'second commit' -u $M
commit(3)
$ echo 'third line(1)' >> s; cp s $S
$ echo 'third line(2)' >> m; cp m $M
$ echo 'third line(3)' >> l; cp l $L
$ hg commit -m 'third commit' -u $L
check alignment of user names in annotate
$ hg annotate -u $M
\xe7\x9f\xad\xe5\x90\x8d: first line(2) (esc)
MIDDLE_: second line(2)
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d: third line(2) (esc)
check alignment of filenames in diffstat
$ hg diff -c tip --stat
MIDDLE_ | 1 +
\xe7\x9f\xad\xe5\x90\x8d | 1 + (esc)
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d | 1 + (esc)
3 files changed, 3 insertions(+), 0 deletions(-)
add branches/tags
$ hg branch $S
marked working directory as branch \xe7\x9f\xad\xe5\x90\x8d (esc)
(branches are permanent and global, did you want a bookmark?)
$ hg tag $S
$ hg book -f $S
$ hg branch $M
marked working directory as branch MIDDLE_
$ hg tag $M
$ hg book -f $M
$ hg branch $L
marked working directory as branch \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d (esc)
$ hg tag $L
$ hg book -f $L
check alignment of branches
$ hg branches
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d 5:d745ff46155b (esc)
MIDDLE_ 4:9259be597f19 (inactive)
\xe7\x9f\xad\xe5\x90\x8d 3:b06c5b6def9e (inactive) (esc)
default 2:64a70663cee8 (inactive)
check alignment of tags
$ hg tags
tip 5:d745ff46155b
\xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d 4:9259be597f19 (esc)
MIDDLE_ 3:b06c5b6def9e
\xe7\x9f\xad\xe5\x90\x8d 2:64a70663cee8 (esc)
check alignment of bookmarks
$ hg book
MIDDLE_ 5:d745ff46155b
\xe7\x9f\xad\xe5\x90\x8d 4:9259be597f19 (esc)
* \xe9\x95\xb7\xe3\x81\x84\xe9\x95\xb7\xe3\x81\x84\xe5\x90\x8d\xe5\x89\x8d 5:d745ff46155b (esc)