dirstate: add a `get_entry` method to the dirstate

This method give access to the underlying `DirstateEntry` object (or an empty
one if None was there). It should allow us to use the more semantic property of
the entry instead of the state where we needs it.

Differential Revision: https://phab.mercurial-scm.org/D11522

mercurial/dirstate.py

@@ -332,6 +332,13 b' class dirstate(object):'
             return entry.state
         return b'?'
 
+    def get_entry(self, path):
+        """return a DirstateItem for the associated path"""
+        entry = self._map.get(path)
+        if entry is None:
+            return DirstateItem()
+        return entry
+
     def __contains__(self, key):
         return key in self._map