dirstatemap: add a common `_insert_entry` method for dirstatemap

This method is called to add a new DirstateItem to the map.

Each variant have a different implementation (which is … the point).

Differential Revision: https://phab.mercurial-scm.org/D11573

mercurial/dirstatemap.py

@@ -101,6 +101,12 b' class _dirstatemapcommon(object):'
     def _refresh_entry(self, f, entry):
         """record updated state of an entry"""
 
+    def _insert_entry(self, f, entry):
+        """add a new dirstate entry (or replace an unrelated one)
+
+        The fact it is actually new is the responsability of the caller
+        """
+
     ### method to manipulate the entries
 
     def set_untracked(self, f):
@@ -403,6 +409,9 b' class dirstatemap(_dirstatemapcommon):'
         if not entry.any_tracked:
             self._map.pop(f, None)
 
+    def _insert_entry(self, f, entry):
+        self._map[f] = entry
+
     def set_possibly_dirty(self, filename):
         """record that the current state of the file on disk is unknown"""
         self[filename].set_possibly_dirty()
@@ -784,6 +793,9 b' if rustmod is not None:'
             else:
                 self._map.addfile(f, entry)
 
+        def _insert_entry(self, f, entry):
+            self._map.addfile(f, entry)
+
         def set_possibly_dirty(self, filename):
             """record that the current state of the file on disk is unknown"""
             entry = self[filename]