workingctx: override _matchstatus for parentworking case

This patch encapsulate the logic for changing the match.bad function when
comparing against the working directory's parent. Future patches will remove
more of the 'if ... else' blocks in localrepo.status that test for this working
directory parent case.

mercurial/context.py

@@ -1351,6 +1351,30 class workingctx(committablectx):
                                                      listunknown)
         return s
 
+    def _matchstatus(self, other, s, match, listignored, listclean,
+                     listunknown):
+        """override the match method with a filter for directory patterns
+
+        We use inheritance to customize the match.bad method only in cases of
+        workingctx since it belongs only to the working directory when
+        comparing against the parent changeset.
+
+        If we aren't comparing against the working directory's parent, then we
+        just use the default match object sent to us.
+        """
+        superself = super(workingctx, self)
+        match = superself._matchstatus(other, s, match, listignored, listclean,
+                                       listunknown)
+        if other != self._repo['.']:
+            def bad(f, msg):
+                # 'f' may be a directory pattern from 'match.files()',
+                # so 'f not in ctx1' is not enough
+                if f not in other and f not in other.dirs():
+                    self._repo.ui.warn('%s: %s\n' %
+                                       (self._repo.dirstate.pathto(f), msg))
+            match.bad = bad
+        return match
+
     def status(self, ignored=False, clean=False, unknown=False, match=None):
         """Explicit status query
         Unless this method is used to query the working copy status, the