hgext/strip.py

status: invalidate dirstate  on LockError

If we cannot take the lock, someone else is modifying the repository. Let us
discard dirstate uncommitted data before exiting the status code.

Having a clean dirstate after such operation seems safer.

Strictly speaking, there is a small behavior change in the following situation:

* process A call `status` outside of the `wlock`
* process B grab the `wlock`
* process A fails to acquires the lock to write status fixup
* process B release the `wlock` *without touching the dirstate*
* process A later grab the `wlock`
* process A can write dirstate update from earlier `status`

However this is a fairly hypothetical situation :
* process A has to be raced
* process B have to not update the dirstate
* process A has to run another *unrelated* operation later.

This seems rare enough to overlook.

I am stating that the two operations in process A has to be unrelated.
Otherwise,  collecting status data outside of the lock to use them inside the
lock is racy. Any other process could move things around (eg: the working copy)
making the data collected during status irrelevantor even harmful.

If such code exists, it should be fixed ASAP.

"""strip changesets and their descendants from history (DEPRECATED)

The functionality of this extension has been included in core Mercurial
since version 5.7. Please use :hg:`debugstrip ...` instead.

This extension allows you to strip changesets and all their descendants from the
repository. See the command help for details.
"""

from mercurial import commands

# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = b'ships-with-hg-core'

# This is a bit ugly, but a uisetup function that defines strip as an
# alias for debugstrip would override any user alias for strip,
# including aliases like "strip = strip --no-backup".
commands.command.rename(old=b'debugstrip', new=b'debugstrip|strip')