dirstate-item: use an explicit __init__ function instead of the attrs one

dirstate-item: use an explicit __init__ function instead of the attrs one

For now, this is not doing anything special, however we plan to make it different in the future. So we start simple.

Differential Revision: https://phab.mercurial-scm.org/D11117

--- a/mercurial/pure/parsers.py	Thu Jul 08 10:28:20 2021 +0200
+++ b/mercurial/pure/parsers.py	Tue Jul 13 13:04:49 2021 +0200
@@ -44,7 +44,7 @@
 AMBIGUOUS_TIME = -1
 
 
-@attr.s(slots=True)
+@attr.s(slots=True, init=False)
 class DirstateItem(object):
     """represent a dirstate entry
 
@@ -61,6 +61,12 @@
     _size = attr.ib()
     _mtime = attr.ib()
 
+    def __init__(self, state, mode, size, mtime):
+        self._state = state
+        self._mode = mode
+        self._size = size
+        self._mtime = mtime
+
     def __getitem__(self, idx):
         if idx == 0 or idx == -4:
             msg = b"do not use item[x], use item.state"