index: don't include nullid in boundary check in pure code

Yet another change that should probably have been part of a3dacabd476b
(index: don't allow index[len(index)] to mean nullid, 2018-07-20).

Differential Revision: https://phab.mercurial-scm.org/D4333

mercurial/pure/parsers.py

@@ -1,176 +1,176 b''
 # parsers.py - Python implementation of parsers.c
 #
 # Copyright 2009 Matt Mackall <[e-mail]> and others
 #
 # 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
 
 import struct
 import zlib
 
 from ..node import nullid
 from .. import pycompat
 stringio = pycompat.bytesio
 
 
 _pack = struct.pack
 _unpack = struct.unpack
 _compress = zlib.compress
 _decompress = zlib.decompress
 
 # Some code below makes tuples directly because it's more convenient. However,
 # code outside this module should always use dirstatetuple.
 def dirstatetuple(*x):
     # x is a tuple
     return x
 
 indexformatng = ">Qiiiiii20s12x"
 indexfirst = struct.calcsize('Q')
 sizeint = struct.calcsize('i')
 indexsize = struct.calcsize(indexformatng)
 
 def gettype(q):
     return int(q & 0xFFFF)
 
 def offset_type(offset, type):
     return int(int(offset) << 16 | type)
 
 class BaseIndexObject(object):
     def __len__(self):
         return self._lgt + len(self._extra)
 
     def append(self, tup):
         self._extra.append(tup)
 
     def _fix_index(self, i):
         if not isinstance(i, int):
             raise TypeError("expecting int indexes")
-        if i < 0 or i >= len(self) + 1:
+        if i < 0 or i >= len(self):
             raise IndexError
         return i
 
     def __getitem__(self, i):
         if i == -1:
             return (0, 0, 0, -1, -1, -1, -1, nullid)
         i = self._fix_index(i)
         if i >= self._lgt:
             return self._extra[i - self._lgt]
         index = self._calculate_index(i)
         r = struct.unpack(indexformatng, self._data[index:index + indexsize])
         if i == 0:
             e = list(r)
             type = gettype(e[0])
             e[0] = offset_type(0, type)
             return tuple(e)
         return r
 
 class IndexObject(BaseIndexObject):
     def __init__(self, data):
         assert len(data) % indexsize == 0
         self._data = data
         self._lgt = len(data) // indexsize
         self._extra = []
 
     def _calculate_index(self, i):
         return i * indexsize
 
     def __delitem__(self, i):
         if not isinstance(i, slice) or not i.stop == -1 or i.step is not None:
             raise ValueError("deleting slices only supports a:-1 with step 1")
         i = self._fix_index(i.start)
         if i < self._lgt:
             self._data = self._data[:i * indexsize]
             self._lgt = i
             self._extra = []
         else:
             self._extra = self._extra[:i - self._lgt]
 
 class InlinedIndexObject(BaseIndexObject):
     def __init__(self, data, inline=0):
         self._data = data
         self._lgt = self._inline_scan(None)
         self._inline_scan(self._lgt)
         self._extra = []
 
     def _inline_scan(self, lgt):
         off = 0
         if lgt is not None:
             self._offsets = [0] * lgt
         count = 0
         while off <= len(self._data) - indexsize:
             s, = struct.unpack('>i',
                 self._data[off + indexfirst:off + sizeint + indexfirst])
             if lgt is not None:
                 self._offsets[count] = off
             count += 1
             off += indexsize + s
         if off != len(self._data):
             raise ValueError("corrupted data")
         return count
 
     def __delitem__(self, i):
         if not isinstance(i, slice) or not i.stop == -1 or i.step is not None:
             raise ValueError("deleting slices only supports a:-1 with step 1")
         i = self._fix_index(i.start)
         if i < self._lgt:
             self._offsets = self._offsets[:i]
             self._lgt = i
             self._extra = []
         else:
             self._extra = self._extra[:i - self._lgt]
 
     def _calculate_index(self, i):
         return self._offsets[i]
 
 def parse_index2(data, inline):
     if not inline:
         return IndexObject(data), None
     return InlinedIndexObject(data, inline), (0, data)
 
 def parse_dirstate(dmap, copymap, st):
     parents = [st[:20], st[20: 40]]
     # dereference fields so they will be local in loop
     format = ">cllll"
     e_size = struct.calcsize(format)
     pos1 = 40
     l = len(st)
 
     # the inner loop
     while pos1 < l:
         pos2 = pos1 + e_size
         e = _unpack(">cllll", st[pos1:pos2]) # a literal here is faster
         pos1 = pos2 + e[4]
         f = st[pos2:pos1]
         if '\0' in f:
             f, c = f.split('\0')
             copymap[f] = c
         dmap[f] = e[:4]
     return parents
 
 def pack_dirstate(dmap, copymap, pl, now):
     now = int(now)
     cs = stringio()
     write = cs.write
     write("".join(pl))
     for f, e in dmap.iteritems():
         if e[0] == 'n' and e[3] == now:
             # The file was last modified "simultaneously" with the current
             # write to dirstate (i.e. within the same second for file-
             # systems with a granularity of 1 sec). This commonly happens
             # for at least a couple of files on 'update'.
             # The user could change the file without changing its size
             # within the same second. Invalidate the file's mtime in
             # dirstate, forcing future 'status' calls to compare the
             # contents of the file if the size is the same. This prevents
             # mistakenly treating such files as clean.
             e = dirstatetuple(e[0], e[1], e[2], -1)
             dmap[f] = e
 
         if f in copymap:
             f = "%s\0%s" % (f, copymap[f])
         e = _pack(">cllll", e[0], e[1], e[2], e[3], len(f))
         write(e)
         write(f)
     return cs.getvalue()