[PATCH] update: do not remove cwd

[Stanislau Hlebik]

Yeap, Augie already noted it.
Warning is probably fine (it’s better than nothing).
Another option is to try to save cwd before update and try to restore it after.

On 8/30/16, 5:45 PM, "Durham Goode" <durham at fb.com> wrote:

    
    
    On 8/29/16 11:50 AM, Stanislau Hlebik wrote:
    > # HG changeset patch
    > # User Stanislau Hlebik <stash at fb.com>
    > # Date 1472496038 25200
    > #      Mon Aug 29 11:40:38 2016 -0700
    > # Node ID e1962781ce84040746ef79c0084b8fd70cfcd4b4
    > # Parent  318e2b600b80e4ed3c6f37df46ec7544f60d4c0b
    > update: do not remove cwd
    >
    > During update directories are deleted as soon as they have no entries.
    > But current working directory shouldn't be deleted because it
    > causes problems for users after hg finishes. Also it makes complex commands
    > like 'hg split' fail.
    Won't this cause update to fail if the parent directory is to be deleted 
    and replaced with a file?  I'd almost err towards just printing a 
    warning message when the current working directory is deleted (and 
    recommending they cd to the root of their repo).
    >
    > diff --git a/mercurial/merge.py b/mercurial/merge.py
    > --- a/mercurial/merge.py
    > +++ b/mercurial/merge.py
    > @@ -1043,7 +1043,7 @@
    >               repo.ui.note(_("removing %s\n") % f)
    >           audit(f)
    >           try:
    > -            unlink(wjoin(f), ignoremissing=True)
    > +            unlink(wjoin(f), ignoremissing=True, donotremovecwd=True)
    >           except OSError as inst:
    >               repo.ui.warn(_("update failed to remove %s: %s!\n") %
    >                            (f, inst.strerror))
    > diff --git a/mercurial/posix.py b/mercurial/posix.py
    > --- a/mercurial/posix.py
    > +++ b/mercurial/posix.py
    > @@ -23,6 +23,7 @@
    >   from .i18n import _
    >   from . import (
    >       encoding,
    > +    osutil,
    >   )
    >   
    >   posixfile = open
    > @@ -496,7 +497,31 @@
    >   def makedir(path, notindexed):
    >       os.mkdir(path)
    >   
    > -def unlinkpath(f, ignoremissing=False):
    > +def removedirs(name, donotremovecwd=False):
    > +    """special version of os.removedirs that does not remove symlinked
    This mentions symlinks are also affected.  That seems unrelated to the 
    purpose of this patch though, and I think we do want to allow symlinks 
    to be deleted if their target contains files.
    > +    directories or junction points if they actually contain files"""
    > +    if not donotremovecwd:
    > +        return os.removedirs(name)
    > +
    > +    cwd = os.getcwd()
    > +    if cwd == name:
    > +        return
    > +    if osutil.listdir(name):
    > +        return
    > +    os.rmdir(name)
    > +    head, tail = os.path.split(name)
    > +    if not tail:
    > +        head, tail = os.path.split(head)
    > +    while head and tail:
    > +        try:
    > +            if osutil.listdir(head) or cwd == head:
    > +                return
    > +            os.rmdir(head)
    > +        except (ValueError, OSError):
    > +            break
    > +        head, tail = os.path.split(head)
    > +
    > +def unlinkpath(f, ignoremissing=False, donotremovecwd=False):
    >       """unlink and remove the directory if it is empty"""
    >       try:
    >           os.unlink(f)
    > @@ -505,7 +530,7 @@
    >               raise
    >       # try removing directories that might now be empty
    >       try:
    > -        os.removedirs(os.path.dirname(f))
    > +        removedirs(os.path.dirname(f), donotremovecwd)
    >       except OSError:
    >           pass
    >   
    > diff --git a/mercurial/windows.py b/mercurial/windows.py
    > --- a/mercurial/windows.py
    > +++ b/mercurial/windows.py
    > @@ -369,11 +369,14 @@
    >       If gid is None, return the name of the current group."""
    >       return None
    >   
    > -def removedirs(name):
    > +def removedirs(name, donotremovecwd=False):
    >       """special version of os.removedirs that does not remove symlinked
    >       directories or junction points if they actually contain files"""
    >       if osutil.listdir(name):
    >           return
    > +    cwd = os.getcwd()
    > +    if donotremovecwd and cwd == name:
    > +        return
    >       os.rmdir(name)
    >       head, tail = os.path.split(name)
    >       if not tail:
    > @@ -382,12 +385,14 @@
    >           try:
    >               if osutil.listdir(head):
    >                   return
    > +            if donotremovecwd and cwd == head:
    > +                return
    >               os.rmdir(head)
    >           except (ValueError, OSError):
    >               break
    >           head, tail = os.path.split(head)
    >   
    > -def unlinkpath(f, ignoremissing=False):
    > +def unlinkpath(f, ignoremissing=False, donotremovecwd=False):
    >       """unlink and remove the directory if it is empty"""
    >       try:
    >           unlink(f)
    > @@ -396,7 +401,7 @@
    >               raise
    >       # try removing directories that might now be empty
    >       try:
    > -        removedirs(os.path.dirname(f))
    > +        removedirs(os.path.dirname(f), donotremovecwd)
    >       except OSError:
    >           pass
    >   
    > diff --git a/tests/test-update-names.t b/tests/test-update-names.t
    > --- a/tests/test-update-names.t
    > +++ b/tests/test-update-names.t
    > @@ -72,3 +72,13 @@
    >     $ cd ..
    >   
    >   #endif
    > +
    > +Test that cwd is not deleted during update
    > +  $ hg init r4 && cd r4
    > +  $ mkdir dir
    > +  $ cd dir
    > +  $ echo a > a
    > +  $ hg add a
    > +  $ hg ci -m "file and dir"
    > +  $ hg up -q null
    > +  $ cd .