demandimport: delay loading for "from a import b" with absolute_import
Before this patch, "from a import b" doesn't delay loading module "b",
if absolute_import is enabled, even though "from . import b" does.
For example:
- it is assumed that extension X has "from P import M" for module M
under package P with absolute_import feature
- if importing module M is already delayed before loading extension
X, loading module M in extension X is delayed until actually
referring
util, cmdutil, scmutil or so of Mercurial itself should be
imported by "from . import M" style before loading extension X
- otherwise, module M is loaded immediately at loading extension X,
even if extension X itself isn't used at that "hg" command invocation
Some minor modules (e.g. filemerge or so) of Mercurial itself
aren't imported by "from . import M" style before loading
extension X. And of course, external libraries aren't, too.
This might cause startup performance problem of hg command, because
many bundled extensions already enable absolute_import feature.
To delay loading module for "from a import b" with absolute_import
feature, this patch does below in "from a (or .a) import b" with
absolute_import case:
1. import root module of "name" by system built-in __import__
(referred as _origimport)
2. recurse down the module chain for hierarchical "name"
This logic can be shared with non absolute_import
case. Therefore, this patch also centralizes it into chainmodules().
3. and fall through to process elements in "fromlist" for the leaf
module of "name"
Processing elements in "fromlist" is executed in the code path
after "if _pypy: .... else: ..." clause. Therefore, this patch
replaces "if _pypy:" with "elif _pypy:" to share it.
At 4f1144c3c72b introducing original "work around" for "from a import
b" case, elements in "fromlist" were imported with "level=level". But
"level" might be grater than 1 (e.g. level=2 in "from .. import b"
case) at demandimport() invocation, and importing direct sub-module in
"fromlist" with level grater than 1 causes unexpected result.
IMHO, this seems main reason of "errors for unknown reason" described
in 4f1144c3c72b, and we don't have to worry about it, because this
issue was already fixed by 78d05778907b.
This is reason why this patch removes "errors for unknown reasons"
comment.
$ . "$TESTDIR/histedit-helpers.sh"
$ cat >> $HGRCPATH <<EOF
> [extensions]
> histedit=
> strip=
> EOF
$ initrepo ()
> {
> hg init r
> cd r
> for x in a b c d e f g; do
> echo $x > $x
> hg add $x
> hg ci -m $x
> done
> }
$ initrepo
log before edit
$ hg log --graph
@ changeset: 6:3c6a8ed2ebe8
| tag: tip
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: g
|
o changeset: 5:652413bf663e
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: f
|
o changeset: 4:e860deea161a
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: e
|
o changeset: 3:055a42cdd887
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: d
|
o changeset: 2:177f92b77385
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: c
|
o changeset: 1:d2ae7f538514
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: b
|
o changeset: 0:cb9a9f314b8b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: a
dirty a file
$ echo a > g
$ hg histedit 177f92b77385 --commands - 2>&1 << EOF
> EOF
abort: uncommitted changes
[255]
$ echo g > g
edit the history
$ hg histedit 177f92b77385 --commands - 2>&1 << EOF| fixbundle
> pick 177f92b77385 c
> pick 055a42cdd887 d
> edit e860deea161a e
> pick 652413bf663e f
> pick 3c6a8ed2ebe8 g
> EOF
0 files updated, 0 files merged, 3 files removed, 0 files unresolved
Editing (e860deea161a), you may commit or record as needed now.
(hg histedit --continue to resume)
try to update and get an error
$ hg update tip
abort: histedit in progress
(use 'hg histedit --continue' or 'hg histedit --abort')
[255]
edit the plan via the editor
$ cat >> $TESTTMP/editplan.sh <<EOF
> cat > \$1 <<EOF2
> drop e860deea161a e
> drop 652413bf663e f
> drop 3c6a8ed2ebe8 g
> EOF2
> EOF
$ HGEDITOR="sh $TESTTMP/editplan.sh" hg histedit --edit-plan
$ cat .hg/histedit-state
v1
055a42cdd88768532f9cf79daa407fc8d138de9b
3c6a8ed2ebe862cc949d2caa30775dd6f16fb799
False
3
drop
e860deea161a2f77de56603b340ebbb4536308ae
drop
652413bf663ef2a641cab26574e46d5f5a64a55a
drop
3c6a8ed2ebe862cc949d2caa30775dd6f16fb799
0
strip-backup/177f92b77385-0ebe6a8f-histedit.hg
edit the plan via --commands
$ hg histedit --edit-plan --commands - 2>&1 << EOF
> edit e860deea161a e
> pick 652413bf663e f
> drop 3c6a8ed2ebe8 g
> EOF
$ cat .hg/histedit-state
v1
055a42cdd88768532f9cf79daa407fc8d138de9b
3c6a8ed2ebe862cc949d2caa30775dd6f16fb799
False
3
edit
e860deea161a2f77de56603b340ebbb4536308ae
pick
652413bf663ef2a641cab26574e46d5f5a64a55a
drop
3c6a8ed2ebe862cc949d2caa30775dd6f16fb799
0
strip-backup/177f92b77385-0ebe6a8f-histedit.hg
Go at a random point and try to continue
$ hg id -n
3+
$ hg up 0
abort: histedit in progress
(use 'hg histedit --continue' or 'hg histedit --abort')
[255]
Try to delete necessary commit
$ hg strip -r 652413b
abort: histedit in progress, can't strip 652413bf663e
[255]
commit, then edit the revision
$ hg ci -m 'wat'
created new head
$ echo a > e
qnew should fail while we're in the middle of the edit step
$ hg --config extensions.mq= qnew please-fail
abort: histedit in progress
(use 'hg histedit --continue' or 'hg histedit --abort')
[255]
$ HGEDITOR='echo foobaz > ' hg histedit --continue 2>&1 | fixbundle
$ hg log --graph
@ changeset: 6:b5f70786f9b0
| tag: tip
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: f
|
o changeset: 5:a5e1ba2f7afb
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: foobaz
|
o changeset: 4:1a60820cd1f6
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: wat
|
o changeset: 3:055a42cdd887
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: d
|
o changeset: 2:177f92b77385
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: c
|
o changeset: 1:d2ae7f538514
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: b
|
o changeset: 0:cb9a9f314b8b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: a
$ hg cat e
a
Stripping necessary commits should not break --abort
$ hg histedit 1a60820cd1f6 --commands - 2>&1 << EOF| fixbundle
> edit 1a60820cd1f6 wat
> pick a5e1ba2f7afb foobaz
> pick b5f70786f9b0 g
> EOF
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
Editing (1a60820cd1f6), you may commit or record as needed now.
(hg histedit --continue to resume)
$ mv .hg/histedit-state .hg/histedit-state.bak
$ hg strip -q -r b5f70786f9b0
$ mv .hg/histedit-state.bak .hg/histedit-state
$ hg histedit --abort
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 3 files
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg log -r .
changeset: 6:b5f70786f9b0
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: f
check histedit_source
$ hg log --debug --rev 5
changeset: 5:a5e1ba2f7afb899ef1581cea528fd885d2fca70d
phase: draft
parent: 4:1a60820cd1f6004a362aa622ebc47d59bc48eb34
parent: -1:0000000000000000000000000000000000000000
manifest: 5:5ad3be8791f39117565557781f5464363b918a45
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: e
extra: branch=default
extra: histedit_source=e860deea161a2f77de56603b340ebbb4536308ae
description:
foobaz
$ hg histedit tip --commands - 2>&1 <<EOF| fixbundle
> edit b5f70786f9b0 f
> EOF
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
Editing (b5f70786f9b0), you may commit or record as needed now.
(hg histedit --continue to resume)
$ hg status
A f
$ hg summary
parent: 5:a5e1ba2f7afb
foobaz
branch: default
commit: 1 added (new branch head)
update: 1 new changesets (update)
phases: 7 draft
hist: 1 remaining (histedit --continue)
(test also that editor is invoked if histedit is continued for
"edit" action)
$ HGEDITOR='cat' hg histedit --continue
f
HG: Enter commit message. Lines beginning with 'HG:' are removed.
HG: Leave message empty to abort commit.
HG: --
HG: user: test
HG: branch 'default'
HG: added f
saved backup bundle to $TESTTMP/r/.hg/strip-backup/b5f70786f9b0-c28d9c86-backup.hg (glob)
$ hg status
log after edit
$ hg log --limit 1
changeset: 6:a107ee126658
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: f
say we'll change the message, but don't.
$ cat > ../edit.sh <<EOF
> cat "\$1" | sed s/pick/mess/ > tmp
> mv tmp "\$1"
> EOF
$ HGEDITOR="sh ../edit.sh" hg histedit tip 2>&1 | fixbundle
$ hg status
$ hg log --limit 1
changeset: 6:1fd3b2fe7754
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: f
modify the message
check saving last-message.txt, at first
$ cat > $TESTTMP/commitfailure.py <<EOF
> from mercurial import error
> def reposetup(ui, repo):
> class commitfailure(repo.__class__):
> def commit(self, *args, **kwargs):
> raise error.Abort('emulating unexpected abort')
> repo.__class__ = commitfailure
> EOF
$ cat >> .hg/hgrc <<EOF
> [extensions]
> # this failure occurs before editor invocation
> commitfailure = $TESTTMP/commitfailure.py
> EOF
$ cat > $TESTTMP/editor.sh <<EOF
> echo "==== before editing"
> cat \$1
> echo "===="
> echo "check saving last-message.txt" >> \$1
> EOF
(test that editor is not invoked before transaction starting)
$ rm -f .hg/last-message.txt
$ HGEDITOR="sh $TESTTMP/editor.sh" hg histedit tip --commands - 2>&1 << EOF | fixbundle
> mess 1fd3b2fe7754 f
> EOF
abort: emulating unexpected abort
$ test -f .hg/last-message.txt
[1]
$ cat >> .hg/hgrc <<EOF
> [extensions]
> commitfailure = !
> EOF
$ hg histedit --abort -q
(test that editor is invoked and commit message is saved into
"last-message.txt")
$ cat >> .hg/hgrc <<EOF
> [hooks]
> # this failure occurs after editor invocation
> pretxncommit.unexpectedabort = false
> EOF
$ hg status --rev '1fd3b2fe7754^1' --rev 1fd3b2fe7754
A f
$ rm -f .hg/last-message.txt
$ HGEDITOR="sh $TESTTMP/editor.sh" hg histedit tip --commands - 2>&1 << EOF
> mess 1fd3b2fe7754 f
> EOF
==== before editing
f
HG: Enter commit message. Lines beginning with 'HG:' are removed.
HG: Leave message empty to abort commit.
HG: --
HG: user: test
HG: branch 'default'
HG: added f
====
note: commit message saved in .hg/last-message.txt
transaction abort!
rollback completed
abort: pretxncommit.unexpectedabort hook exited with status 1
[255]
$ cat .hg/last-message.txt
f
check saving last-message.txt
(test also that editor is invoked if histedit is continued for "message"
action)
$ HGEDITOR=cat hg histedit --continue
f
HG: Enter commit message. Lines beginning with 'HG:' are removed.
HG: Leave message empty to abort commit.
HG: --
HG: user: test
HG: branch 'default'
HG: added f
note: commit message saved in .hg/last-message.txt
transaction abort!
rollback completed
abort: pretxncommit.unexpectedabort hook exited with status 1
[255]
$ cat >> .hg/hgrc <<EOF
> [hooks]
> pretxncommit.unexpectedabort =
> EOF
$ hg histedit --abort -q
then, check "modify the message" itself
$ hg histedit tip --commands - 2>&1 << EOF | fixbundle
> mess 1fd3b2fe7754 f
> EOF
$ hg status
$ hg log --limit 1
changeset: 6:62feedb1200e
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: f
rollback should not work after a histedit
$ hg rollback
no rollback information available
[1]
$ cd ..
$ hg clone -qr0 r r0
$ cd r0
$ hg phase -fdr0
$ hg histedit --commands - 0 2>&1 << EOF
> edit cb9a9f314b8b a > $EDITED
> EOF
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
adding a
Editing (cb9a9f314b8b), you may commit or record as needed now.
(hg histedit --continue to resume)
[1]
$ HGEDITOR=true hg histedit --continue
saved backup bundle to $TESTTMP/r0/.hg/strip-backup/cb9a9f314b8b-cc5ccb0b-backup.hg (glob)
$ hg log -G
@ changeset: 0:0efcea34f18a
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: a
$ echo foo >> b
$ hg addr
adding b
$ hg ci -m 'add b'
$ echo foo >> a
$ hg ci -m 'extend a'
$ hg phase --public 1
Attempting to fold a change into a public change should not work:
$ cat > ../edit.sh <<EOF
> cat "\$1" | sed s/pick/fold/ > tmp
> mv tmp "\$1"
> EOF
$ HGEDITOR="sh ../edit.sh" hg histedit 2
warning: histedit rules saved to: .hg/histedit-last-edit.txt
hg: parse error: cannot fold into public change 18aa70c8ad22
[255]
$ cat .hg/histedit-last-edit.txt
fold 0012be4a27ea 2 extend a
# Edit history between 0012be4a27ea and 0012be4a27ea
#
# Commits are listed from least to most recent
#
# You can reorder changesets by reordering the lines
#
# Commands:
#
# e, edit = use commit, but stop for amending
# m, mess = edit commit message without changing commit content
# p, fold = use commit
# d, drop = remove commit from history
# f, fold = use commit, but combine it with the one above
# r, roll = like fold, but discard this commit's description
#