revlogutils: move the NodeMap class in a dedicated nodemap module

We will introduce more nodemap related code, so it make sense to move the
existing code in that module first.

Differential Revision: https://phab.mercurial-scm.org/D7809

mercurial/revlogutils/nodemap.py

@@ -0,0 +1,15 b''
+# nodemap.py - nodemap related code and utilities
+#
+# Copyright 2019 Pierre-Yves David <[e-mail]>
+# Copyright 2019 George Racinet <[e-mail]>
+#
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2 or any later version.
+
+from __future__ import absolute_import
+from .. import error
+
+
+class NodeMap(dict):
+    def __missing__(self, x):
+        raise error.RevlogError(b'unknown node: %s' % x)

mercurial/pure/parsers.py

@@ -13,10 +13,11 b' import zlib'
 from ..node import nullid, nullrev
 from .. import (
     pycompat,
-    revlogutils,
     util,
 )
 
+from ..revlogutils import nodemap as nodemaputil
+
 stringio = pycompat.bytesio
 
 
@@ -55,7 +56,7 b' class BaseIndexObject(object):'
 
     @util.propertycache
     def _nodemap(self):
-        nodemap = revlogutils.NodeMap({nullid: nullrev})
+        nodemap = nodemaputil.NodeMap({nullid: nullrev})
         for r in range(0, len(self)):
             n = self[r][7]
             nodemap[n] = r

mercurial/revlog.py

@@ -65,7 +65,6 b' from . import ('
     mdiff,
     policy,
     pycompat,
-    revlogutils,
     templatefilters,
     util,
 )
@@ -76,6 +75,7 b' from .interfaces import ('
 from .revlogutils import (
     deltas as deltautil,
     flagutil,
+    nodemap as nodemaputil,
     sidedata as sidedatautil,
 )
 from .utils import (
@@ -224,7 +224,7 b' class revlogoldindex(list):'
 
     @util.propertycache
     def _nodemap(self):
-        nodemap = revlogutils.NodeMap({nullid: nullrev})
+        nodemap = nodemaputil.NodeMap({nullid: nullrev})
         for r in range(0, len(self)):
             n = self[r][7]
             nodemap[n] = r
@@ -273,7 +273,7 b' class revlogoldio(object):'
     def parseindex(self, data, inline):
         s = self.size
         index = []
-        nodemap = revlogutils.NodeMap({nullid: nullrev})
+        nodemap = nodemaputil.NodeMap({nullid: nullrev})
         n = off = 0
         l = len(data)
         while off + s <= l:

mercurial/revlogutils/__init__.py

@@ -6,9 +6,3 b''
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import
-from .. import error
-
-
-class NodeMap(dict):
-    def __missing__(self, x):
-        raise error.RevlogError(b'unknown node: %s' % x)