view tests/test-mq-qrefresh-replace-log-message.t @ 30779:38aa1ca97b6a

repair: migrate revlogs during upgrade

Our next step for in-place upgrade is to migrate store data. Revlogs
are the biggest source of data within the store and a store is useless
without them, so we implement their migration first.

Our strategy for migrating revlogs is to walk the store and call
`revlog.clone()` on each revlog. There are some minor complications.

Because revlogs have different storage options (e.g. changelog has
generaldelta and delta chains disabled), we need to obtain the
correct class of revlog so inserted data is encoded properly for its
type.

Various attempts at implementing progress indicators that didn't lead
to frustration from false "it's almost done" indicators were made.

I initially used a single progress bar based on number of revlogs.
However, this quickly churned through all filelogs, got to 99% then
effectively froze at 99.99% when it got to the manifest.

So I converted the progress bar to total revision count. This was a
little bit better. But the manifest was still significantly slower
than filelogs and it took forever to process the last few percent.

I then tried both revision/chunk bytes and raw bytes as the
denominator. This had the opposite effect: because so much data is in
manifests, it would churn through filelogs without showing much
progress. When it got to manifests, it would fill in 90+% of the
progress bar.

I finally gave up having a unified progress bar and instead implemented
3 progress bars: 1 for filelog revisions, 1 for manifest revisions, and
1 for changelog revisions. I added extra messages indicating the total
number of revisions of each so users know there are more progress bars
coming.

I also added extra messages before and after each stage to give extra
details about what is happening. Strictly speaking, this isn't
necessary. But the numbers are impressive. For example, when converting
a non-generaldelta mozilla-central repository, the messages you see are:

   migrating 2475593 total revisions (1833043 in filelogs, 321156 in manifests, 321394 in changelog)
   migrating 1.67 GB in store; 2508 GB tracked data
   migrating 267868 filelogs containing 1833043 revisions (1.09 GB in store; 57.3 GB tracked data)
   finished migrating 1833043 filelog revisions across 267868 filelogs; change in size: -415776 bytes
   migrating 1 manifests containing 321156 revisions (518 MB in store; 2451 GB tracked data)

That "2508 GB" figure really blew me away. I had no clue that the raw
tracked data in mozilla-central was that large. Granted, 2451 GB is in
the manifest and "only" 57.3 GB is in filelogs. But still.

It's worth noting that gratuitous loading of source revlogs in order
to display numbers and progress bars does serve a purpose: it ensures
we can open all source revlogs. We don't want to spend several minutes
copying revlogs only to encounter a permissions error or similar later.

As part of this commit, we also add swapping of the store directory
to the upgrade function. After revlogs are converted, we move the
old store into the backup directory then move the temporary repo's
store into the old store's location. On well-behaved systems, this
should be 2 atomic operations and the window of inconsistency show be
very narrow.

There are still a few improvements to be made to store copying and
upgrading. But this commit gets the bulk of the work out of the way.

Environment setup for MQ

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "mq=" >> $HGRCPATH
  $ cat >> $HGRCPATH <<EOF
  > [defaults]
  > # explicit date to commit with fixed hashid
  > qnew = -d "0 0"
  > qrefresh = -d "0 0"
  > qfold = -d "0 0"
  > EOF
  $ hg init
  $ hg qinit

Should fail if no patches applied
(this tests also that editor is not invoked if '--edit' is not
specified)

  $ hg qrefresh
  no patches applied
  [1]
  $ hg qrefresh -e
  no patches applied
  [1]
  $ hg qnew -m "First commit message" first-patch
  $ echo aaaa > file
  $ hg add file
  $ HGEDITOR=cat hg qrefresh

Should display 'First commit message'

  $ hg log -l1 --template "{desc}\n"
  First commit message

Testing changing message with -m
(this tests also that '--edit' can be used with '--message', and
that '[committemplate] changeset' definition and commit log specific
template keyword 'extramsg' work well)

  $ cat >> .hg/hgrc <<EOF
  > [committemplate]
  > listupfiles = {file_adds %
  >    "HG: added {file}\n"     }{file_mods %
  >    "HG: changed {file}\n"   }{file_dels %
  >    "HG: removed {file}\n"   }{if(files, "",
  >    "HG: no files changed\n")}
  > 
  > changeset = HG: this is customized commit template
  >     {desc}\n\n
  >     HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  >     HG: {extramsg}
  >     HG: --
  >     HG: user: {author}
  >     HG: branch '{branch}'\n{listupfiles}
  > EOF

  $ echo bbbb > file
  $ HGEDITOR=cat hg qrefresh -m "Second commit message" -e
  HG: this is customized commit template
  Second commit message
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to use default message.
  HG: --
  HG: user: test
  HG: branch 'default'
  HG: added file

  $ cat >> .hg/hgrc <<EOF
  > # disable customizing for subsequent tests
  > [committemplate]
  > changeset =
  > EOF

Should display 'Second commit message'

  $ hg log -l1 --template "{desc}\n"
  Second commit message

Testing changing message with -l

  $ echo "Third commit message" > logfile
  $ echo " This is the 3rd log message" >> logfile
  $ echo bbbb > file
  $ hg qrefresh -l logfile

Should display 'Third commit message\\\n This is the 3rd log message'

  $ hg log -l1 --template "{desc}\n"
  Third commit message
   This is the 3rd log message

Testing changing message with -l-

  $ hg qnew -m "First commit message" second-patch
  $ echo aaaa > file2
  $ hg add file2
  $ echo bbbb > file2
  $ (echo "Fifth commit message"; echo " This is the 5th log message") | hg qrefresh -l-

Should display 'Fifth commit message\\\n This is the 5th log message'

  $ hg log -l1 --template "{desc}\n"
  Fifth commit message
   This is the 5th log message

Test saving last-message.txt:

  $ cat > $TESTTMP/editor.sh << EOF
  > echo "==== before editing"
  > cat \$1
  > echo "===="
  > (echo; echo "test saving last-message.txt") >> \$1
  > EOF

  $ 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

  $ hg qapplied
  first-patch
  second-patch
  $ hg tip --template "{files}\n"
  file2

(test that editor is not invoked before transaction starting)

  $ rm -f .hg/last-message.txt
  $ HGEDITOR="sh $TESTTMP/editor.sh" hg qrefresh -e
  qrefresh interrupted while patch was popped! (revert --all, qpush to recover)
  abort: emulating unexpected abort
  [255]
  $ test -f .hg/last-message.txt
  [1]

(reset applied patches and directory status)

  $ cat >> .hg/hgrc <<EOF
  > [extensions]
  > commitfailure = !
  > EOF

  $ hg qapplied
  first-patch
  $ hg status -A file2
  ? file2
  $ rm file2
  $ hg qpush -q second-patch
  now at: second-patch

(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

  $ rm -f .hg/last-message.txt
  $ hg status --rev "second-patch^1" -arm
  A file2
  $ HGEDITOR="sh $TESTTMP/editor.sh" hg qrefresh -e
  ==== before editing
  Fifth commit message
   This is the 5th log message
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to use default message.
  HG: --
  HG: user: test
  HG: branch 'default'
  HG: added file2
  ====
  note: commit message saved in .hg/last-message.txt
  transaction abort!
  rollback completed
  qrefresh interrupted while patch was popped! (revert --all, qpush to recover)
  abort: pretxncommit.unexpectedabort hook exited with status 1
  [255]
  $ cat .hg/last-message.txt
  Fifth commit message
   This is the 5th log message
  
  
  
  test saving last-message.txt

Test visibility of in-memory dirstate changes outside transaction to
external process

  $ cat > $TESTTMP/checkvisibility.sh <<EOF
  > echo "===="
  > hg parents --template "{rev}:{node|short}\n"
  > hg status -arm
  > echo "===="
  > EOF

== test visibility to external editor

  $ hg update -C -q first-patch
  $ rm -f file2
  $ hg qpush -q second-patch --config hooks.pretxncommit.unexpectedabort=
  now at: second-patch
  $ echo bbbb >> file2

  $ sh "$TESTTMP/checkvisibility.sh"
  ====
  1:e30108269082
  M file2
  ====

  $ HGEDITOR="sh \"$TESTTMP/checkvisibility.sh\"" hg qrefresh -e
  ====
  0:25e397dabed2
  A file2
  ====
  note: commit message saved in .hg/last-message.txt
  transaction abort!
  rollback completed
  qrefresh interrupted while patch was popped! (revert --all, qpush to recover)
  abort: pretxncommit.unexpectedabort hook exited with status 1
  [255]

(rebuilding at failure of qrefresh bases on rev #0, and it causes
dropping status of "file2")

  $ sh "$TESTTMP/checkvisibility.sh"
  ====
  0:25e397dabed2
  ====

== test visibility to precommit external hook

  $ hg update -C -q
  $ rm -f file2
  $ hg qpush -q second-patch --config hooks.pretxncommit.unexpectedabort=
  now at: second-patch
  $ echo bbbb >> file2

  $ cat >> .hg/hgrc <<EOF
  > [hooks]
  > precommit.checkvisibility = sh "$TESTTMP/checkvisibility.sh"
  > EOF

  $ sh "$TESTTMP/checkvisibility.sh"
  ====
  1:e30108269082
  M file2
  ====

  $ hg qrefresh
  ====
  0:25e397dabed2
  A file2
  ====
  transaction abort!
  rollback completed
  qrefresh interrupted while patch was popped! (revert --all, qpush to recover)
  abort: pretxncommit.unexpectedabort hook exited with status 1
  [255]

  $ sh "$TESTTMP/checkvisibility.sh"
  ====
  0:25e397dabed2
  ====

  $ cat >> .hg/hgrc <<EOF
  > [hooks]
  > precommit.checkvisibility =
  > EOF

== test visibility to pretxncommit external hook

  $ hg update -C -q
  $ rm -f file2
  $ hg qpush -q second-patch --config hooks.pretxncommit.unexpectedabort=
  now at: second-patch
  $ echo bbbb >> file2

  $ cat >> .hg/hgrc <<EOF
  > [hooks]
  > pretxncommit.checkvisibility = sh "$TESTTMP/checkvisibility.sh"
  > # make checkvisibility run before unexpectedabort
  > priority.pretxncommit.checkvisibility = 10
  > EOF

  $ sh "$TESTTMP/checkvisibility.sh"
  ====
  1:e30108269082
  M file2
  ====

  $ hg qrefresh
  ====
  0:25e397dabed2
  A file2
  ====
  transaction abort!
  rollback completed
  qrefresh interrupted while patch was popped! (revert --all, qpush to recover)
  abort: pretxncommit.unexpectedabort hook exited with status 1
  [255]

  $ sh "$TESTTMP/checkvisibility.sh"
  ====
  0:25e397dabed2
  ====

  $ cat >> .hg/hgrc <<EOF
  > [hooks]
  > pretxncommit.checkvisibility =
  > EOF