encoding: add fast path of from/toutf8b() for ASCII strings
See the previous patch for why.
The added test seems not making much sense because ASCII strings should
never contain "\xed" and be valid UTF-8.
(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)
(fast jsonescape)
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)
(this patch)
time: real 5.190 secs (user 5.120+0.000 sys 0.070+0.000)
time: real 5.230 secs (user 5.170+0.000 sys 0.050+0.000)
time: real 5.220 secs (user 5.150+0.000 sys 0.070+0.000)
syntax: glob
*.elc
*.tmp
*.orig
*.rej
*~
*.mergebackup
*.o
*.so
*.dll
*.exe
*.pyd
*.pyc
*.pyo
*$py.class
*.swp
*.prof
*.zip
\#*\#
.\#*
tests/.coverage*
tests/.testtimes*
tests/.hypothesis
tests/hypothesis-generated
tests/annotated
tests/*.err
tests/htmlcov
build
contrib/chg/chg
contrib/hgsh/hgsh
contrib/vagrant/.vagrant
contrib/docker/debian-*
contrib/docker/ubuntu-*
dist
packages
doc/common.txt
doc/*.[0-9]
doc/*.[0-9].txt
doc/*.[0-9].gendoc.txt
doc/*.[0-9].{x,ht}ml
MANIFEST
MANIFEST.in
patches
mercurial/__modulepolicy__.py
mercurial/__version__.py
mercurial/hgpythonlib.h
mercurial.egg-info
.DS_Store
tags
cscope.*
.idea/*
.asv/*
i18n/hg.pot
locale/*/LC_MESSAGES/hg.mo
hgext/__index__.py
# Generated wheels
wheelhouse/
syntax: regexp
^\.pc/
^\.(pydev)?project
# hackable windows distribution additions
^hg-python
^hg.py$