encoding: change jsonmap to a list indexed by code point
This is slightly faster and convenient to implement a paranoid escaping.
$ python -m timeit \
-s 'from mercurial import encoding; data = str(bytearray(xrange(128)))' \
'encoding.jsonescape(data)'
original: 100000 loops, best of 3: 15.1 usec per loop
this patch: 100000 loops, best of 3: 13.7 usec per loop
--- a/mercurial/encoding.py Tue Feb 02 15:24:11 2016 +0000
+++ b/mercurial/encoding.py Sat Jan 30 19:41:34 2016 +0900
@@ -378,7 +378,7 @@
upper = 1
other = 0
-_jsonmap = {}
+_jsonmap = []
def jsonescape(s):
'''returns a string suitable for JSON
@@ -408,21 +408,18 @@
'''
if not _jsonmap:
- for x in xrange(32):
- _jsonmap[chr(x)] = "\\u%04x" % x
- for x in xrange(32, 256):
- c = chr(x)
- _jsonmap[c] = c
- _jsonmap['\x7f'] = '\\u007f'
- _jsonmap['\t'] = '\\t'
- _jsonmap['\n'] = '\\n'
- _jsonmap['\"'] = '\\"'
- _jsonmap['\\'] = '\\\\'
- _jsonmap['\b'] = '\\b'
- _jsonmap['\f'] = '\\f'
- _jsonmap['\r'] = '\\r'
+ _jsonmap.extend("\\u%04x" % x for x in xrange(32))
+ _jsonmap.extend(chr(x) for x in xrange(32, 256))
+ _jsonmap[0x7f] = '\\u007f'
+ _jsonmap[0x09] = '\\t'
+ _jsonmap[0x0a] = '\\n'
+ _jsonmap[0x22] = '\\"'
+ _jsonmap[0x5c] = '\\\\'
+ _jsonmap[0x08] = '\\b'
+ _jsonmap[0x0c] = '\\f'
+ _jsonmap[0x0d] = '\\r'
- return ''.join(_jsonmap[c] for c in toutf8b(s))
+ return ''.join(_jsonmap[x] for x in bytearray(toutf8b(s)))
_utf8len = [0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 4]