view tests/test-context-metadata.t @ 44311:2b72c4ff8ed1

nodemap: use an intermediate "docket" file to carry small metadata

This intermediate file will make mmapping, transaction and content validation
easier. (Most of this usefulness will arrive gradually in later changeset). In
particular it will become very useful to append new data are the end of raw file
instead of rewriting on the file on each transaction.

See in code comments for details.

Differential Revision: https://phab.mercurial-scm.org/D7838

Tests about metadataonlyctx

  $ hg init
  $ echo A > A
  $ hg commit -A A -m 'Add A'
  $ echo B > B
  $ hg commit -A B -m 'Add B'
  $ hg rm A
  $ echo C > C
  $ echo B2 > B
  $ hg add C -q
  $ hg commit -m 'Remove A'

  $ cat > metaedit.py <<EOF
  > from __future__ import absolute_import
  > from mercurial import context, pycompat, registrar
  > cmdtable = {}
  > command = registrar.command(cmdtable)
  > @command(b'metaedit')
  > def metaedit(ui, repo, arg):
  >     # Modify commit message to "FOO"
  >     with repo.wlock(), repo.lock(), repo.transaction(b'metaedit'):
  >         old = repo[b'.']
  >         kwargs = dict(s.split(b'=', 1) for s in arg.split(b';'))
  >         if b'parents' in kwargs:
  >             kwargs[b'parents'] = map(int, kwargs[b'parents'].split(b','))
  >         new = context.metadataonlyctx(repo, old,
  >                                       **pycompat.strkwargs(kwargs))
  >         new.commit()
  > EOF
  $ hg --config extensions.metaedit=$TESTTMP/metaedit.py metaedit 'text=Changed'
  $ hg log -r tip
  changeset:   3:ad83e9e00ec9
  tag:         tip
  parent:      1:3afb7afe6632
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Changed
  
  $ hg --config extensions.metaedit=$TESTTMP/metaedit.py metaedit 'parents=0' 2>&1 | egrep '^RuntimeError'
  RuntimeError: can't reuse the manifest: its p1 doesn't match the new ctx p1

  $ hg --config extensions.metaedit=$TESTTMP/metaedit.py metaedit 'user=foo <[e-mail]>'
  $ hg log -r tip
  changeset:   4:1f86eaeca92b
  tag:         tip
  parent:      1:3afb7afe6632
  user:        foo <[e-mail]>
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Remove A