Replace RE2 import with a dependency

third_party/re2/re2/make_unicode_casefold.py

-#!/usr/bin/python
-# coding=utf-8
-#
-# Copyright 2008 The RE2 Authors.  All Rights Reserved.
-# Use of this source code is governed by a BSD-style
-# license that can be found in the LICENSE file.
-
-# See unicode_casefold.h for description of case folding tables.
-
-"""Generate C++ table for Unicode case folding."""
-
-import sys
-import unicode
-
-_header = """
-// GENERATED BY make_unicode_casefold.py; DO NOT EDIT.
-// make_unicode_casefold.py >unicode_casefold.cc
-
-#include "re2/unicode_casefold.h"
-
-namespace re2 {
-
-"""
-
-_trailer = """
-
-} // namespace re2
-
-"""
-
-def _Delta(a, b):
-  """Compute the delta for b - a.  Even/odd and odd/even
-     are handled specially, as described above."""
-  if a+1 == b:
-    if a%2 == 0:
-      return 'EvenOdd'
-    else:
-      return 'OddEven'
-  if a == b+1:
-    if a%2 == 0:
-      return 'OddEven'
-    else:
-      return 'EvenOdd'
-  return b - a
-
-def _AddDelta(a, delta):
-  """Return a + delta, handling EvenOdd and OddEven specially."""
-  if type(delta) == int:
-    return a+delta
-  if delta == 'EvenOdd':
-    if a%2 == 0:
-      return a+1
-    else:
-      return a-1
-  if delta == 'OddEven':
-    if a%2 == 1:
-      return a+1
-    else:
-      return a-1
-  print >>sys.stderr, "Bad Delta: ", delta
-  raise "Bad Delta"
-
-def _MakeRanges(pairs):
-  """Turn a list like [(65,97), (66, 98), ..., (90,122)]
-     into [(65, 90, +32)]."""
-  ranges = []
-  last = -100
-
-  def evenodd(last, a, b, r):
-    if a != last+1 or b != _AddDelta(a, r[2]):
-      return False
-    r[1] = a
-    return True
-
-  def evenoddpair(last, a, b, r):
-    if a != last+2:
-      return False
-    delta = r[2]
-    d = delta
-    if type(delta) is not str:
-      return False
-    if delta.endswith('Skip'):
-      d = delta[:-4]
-    else:
-      delta = d + 'Skip'
-    if b != _AddDelta(a, d):
-      return False
-    r[1] = a
-    r[2] = delta
-    return True
-
-  for a, b in pairs:
-    if ranges and evenodd(last, a, b, ranges[-1]):
-      pass
-    elif ranges and evenoddpair(last, a, b, ranges[-1]):
-      pass
-    else:
-      ranges.append([a, a, _Delta(a, b)])
-    last = a
-  return ranges
-
-# The maximum size of a case-folding group.
-# Case folding is implemented in parse.cc by a recursive process
-# with a recursion depth equal to the size of the largest
-# case-folding group, so it is important that this bound be small.
-# The current tables have no group bigger than 4.
-# If there are ever groups bigger than 10 or so, it will be
-# time to rework the code in parse.cc.
-MaxCasefoldGroup = 4
-
-def main():
-  lowergroups, casegroups = unicode.CaseGroups()
-  foldpairs = []
-  seen = {}
-  for c in casegroups:
-    if len(c) > MaxCasefoldGroup:
-      raise unicode.Error("casefold group too long: %s" % (c,))
-    for i in range(len(c)):
-      if c[i-1] in seen:
-        raise unicode.Error("bad casegroups %d -> %d" % (c[i-1], c[i]))
-      seen[c[i-1]] = True
-      foldpairs.append([c[i-1], c[i]])
-
-  lowerpairs = []
-  for lower, group in lowergroups.iteritems():
-    for g in group:
-      if g != lower:
-        lowerpairs.append([g, lower])
-
-  def printpairs(name, foldpairs):
-    foldpairs.sort()
-    foldranges = _MakeRanges(foldpairs)
-    print "// %d groups, %d pairs, %d ranges" % (len(casegroups), len(foldpairs), len(foldranges))
-    print "const CaseFold unicode_%s[] = {" % (name,)
-    for lo, hi, delta in foldranges:
-      print "\t{ %d, %d, %s }," % (lo, hi, delta)
-    print "};"
-    print "const int num_unicode_%s = %d;" % (name, len(foldranges),)
-    print ""
-
-  print _header
-  printpairs("casefold", foldpairs)
-  printpairs("tolower", lowerpairs)
-  print _trailer
-
-if __name__ == '__main__':
-  main()