diff mercurial/encoding.py @ 33943:2c37f9dabc32

encoding: add fast path of jsonescape() (issue5533)

This isn't highly optimized as it copies characters one by one, but seems
reasonably simple and not slow.

  (with mercurial repo)
  $ export HGRCPATH=/dev/null HGPLAIN=
  $ hg log --time --config experimental.stabilization=all -Tjson > /dev/null

  (original)
  time: real 6.830 secs (user 6.740+0.000 sys 0.080+0.000)
  time: real 6.690 secs (user 6.650+0.000 sys 0.040+0.000)
  time: real 6.700 secs (user 6.640+0.000 sys 0.060+0.000)

  (this patch)
  time: real 5.630 secs (user 5.550+0.000 sys 0.070+0.000)
  time: real 5.700 secs (user 5.650+0.000 sys 0.050+0.000)
  time: real 5.690 secs (user 5.640+0.000 sys 0.050+0.000)

--- a/mercurial/encoding.py	Sun Apr 23 16:10:51 2017 +0900
+++ b/mercurial/encoding.py	Sun Apr 23 14:47:52 2017 +0900
@@ -26,7 +26,7 @@
 
 asciilower = charencode.asciilower
 asciiupper = charencode.asciiupper
-_jsonescapeu8fast = charencodepure.jsonescapeu8fast  # TODO: no "pure"
+_jsonescapeu8fast = charencode.jsonescapeu8fast
 
 _sysstr = pycompat.sysstr
 
@@ -404,8 +404,8 @@
     'this is a test'
     >>> jsonescape('escape characters: \\0 \\x0b \\x7f')
     'escape characters: \\\\u0000 \\\\u000b \\\\u007f'
-    >>> jsonescape('escape characters: \\t \\n \\r \\" \\\\')
-    'escape characters: \\\\t \\\\n \\\\r \\\\" \\\\\\\\'
+    >>> jsonescape('escape characters: \\b \\t \\n \\f \\r \\" \\\\')
+    'escape characters: \\\\b \\\\t \\\\n \\\\f \\\\r \\\\" \\\\\\\\'
     >>> jsonescape('a weird byte: \\xdd')
     'a weird byte: \\xed\\xb3\\x9d'
     >>> jsonescape('utf-8: caf\\xc3\\xa9')
@@ -416,6 +416,10 @@
     If paranoid, non-ascii and common troublesome characters are also escaped.
     This is suitable for web output.
 
+    >>> s = 'escape characters: \\0 \\x0b \\x7f'
+    >>> assert jsonescape(s) == jsonescape(s, paranoid=True)
+    >>> s = 'escape characters: \\b \\t \\n \\f \\r \\" \\\\'
+    >>> assert jsonescape(s) == jsonescape(s, paranoid=True)
     >>> jsonescape('escape boundary: \\x7e \\x7f \\xc2\\x80', paranoid=True)
     'escape boundary: ~ \\\\u007f \\\\u0080'
     >>> jsonescape('a weird byte: \\xdd', paranoid=True)