subrepo: be more careful with deletions of .hgsub and .hgsubstate (issue2844)

subrepo: be more careful with deletions of .hgsub and .hgsubstate (issue2844)

We shouldn't try to process subrepos if .hgsub isn't present and we
should remove .hgsubstate if .hgsub is marked for removal.

--- a/mercurial/localrepo.py	Sun Jun 05 22:26:01 2011 +0200
+++ b/mercurial/localrepo.py	Mon Jun 06 15:17:40 2011 -0500
@@ -944,18 +944,28 @@
             # check subrepos
             subs = []
             removedsubs = set()
-            for p in wctx.parents():
-                removedsubs.update(s for s in p.substate if match(s))
-            for s in wctx.substate:
-                removedsubs.discard(s)
-                if match(s) and wctx.sub(s).dirty():
-                    subs.append(s)
-            if (subs or removedsubs):
-                if (not match('.hgsub') and
-                    '.hgsub' in (wctx.modified() + wctx.added())):
-                    raise util.Abort(_("can't commit subrepos without .hgsub"))
-                if '.hgsubstate' not in changes[0]:
-                    changes[0].insert(0, '.hgsubstate')
+            if '.hgsub' in wctx:
+                # only manage subrepos and .hgsubstate if .hgsub is present
+                for p in wctx.parents():
+                    removedsubs.update(s for s in p.substate if match(s))
+                for s in wctx.substate:
+                    removedsubs.discard(s)
+                    if match(s) and wctx.sub(s).dirty():
+                        subs.append(s)
+                if (subs or removedsubs):
+                    if (not match('.hgsub') and
+                        '.hgsub' in (wctx.modified() + wctx.added())):
+                        raise util.Abort(
+                            _("can't commit subrepos without .hgsub"))
+                    if '.hgsubstate' not in changes[0]:
+                        changes[0].insert(0, '.hgsubstate')
+                        if '.hgsubstate' in changes[2]:
+                            changes[2].remove('.hgsubstate')
+            elif '.hgsub' in changes[2]:
+                # clean up .hgsubstate when .hgsub is removed
+                if ('.hgsubstate' in wctx and
+                    '.hgsubstate' not in changes[0] + changes[1] + changes[2]):
+                    changes[2].insert(0, '.hgsubstate')
 
             if subs and not self.ui.configbool('ui', 'commitsubrepos', True):
                 changedsubs = [s for s in subs if wctx.sub(s).dirty(True)]

--- a/tests/test-subrepo.t	Sun Jun 05 22:26:01 2011 +0200
+++ b/tests/test-subrepo.t	Mon Jun 06 15:17:40 2011 -0500
@@ -500,6 +500,7 @@
   $ hg -R testdelete remove testdelete/.hgsub
   $ hg -R testdelete ci -m ".hgsub deleted"
   $ cat testdelete/.hgsubstate
+  bdf5c9a3103743d900b12ae0db3ffdcfd7b0d878 nested
 
 test repository cloning
 
@@ -823,3 +824,36 @@
   fc627a69481f
   $ hg -R t id 
   e95bcfa18a35
+
+Test that removing .hgsubstate doesn't break anything:
+
+  $ hg rm -f .hgsubstate
+  $ hg ci -mrm
+  committing subrepository s
+  committing subrepository t
+  created new head
+  $ hg log -vr tip
+  changeset:   14:3941e0aa5236
+  tag:         tip
+  parent:      11:365661e5936a
+  user:        test
+  date:        Thu Jan 01 00:00:00 1970 +0000
+  description:
+  rm
+  
+  
+
+Test that removing .hgsub removes .hgsubstate:
+
+  $ hg rm .hgsub
+  $ hg ci -mrm2
+  $ hg log -vr tip
+  changeset:   15:8b31de9d13d1
+  tag:         tip
+  user:        test
+  date:        Thu Jan 01 00:00:00 1970 +0000
+  files:       .hgsub .hgsubstate
+  description:
+  rm2
+  
+