encoding: fix trim() to be O(n) instead of O(n^2)
`encoding.trim()` iterated over the possible lengths smaller than the
input and created a slice for each. It then calculated the column
width of the result, which is of course O(n), so the overall algorithm
was O(n). This patch rewrites it to iterate over the unicode
characters, keeping track of the length so far. Also, the old
algorithm started from the end of the string, which made it much worse
when the input is large and the limit is small (such as the typical 72
we pass to it).
You can time it by running something like this:
```
time python3 -c 'from mercurial.utils import stringutil; print(stringutil.ellipsis(b"0123456789" * 1000, 5))'
```
That drops from 4.05 s to 83 ms with this patch (and most of that is
of course startup time).
Differential Revision: https://phab.mercurial-scm.org/D12089
# this is hack to make sure no escape characters are inserted into the output
from __future__ import absolute_import
from __future__ import print_function
import doctest
import os
import re
import subprocess
import sys
ispy3 = sys.version_info[0] >= 3
if 'TERM' in os.environ:
del os.environ['TERM']
class py3docchecker(doctest.OutputChecker):
def check_output(self, want, got, optionflags):
want2 = re.sub(r'''\bu(['"])(.*?)\1''', r'\1\2\1', want) # py2: u''
got2 = re.sub(r'''\bb(['"])(.*?)\1''', r'\1\2\1', got) # py3: b''
# py3: <exc.name>: b'<msg>' -> <name>: <msg>
# <exc.name>: <others> -> <name>: <others>
got2 = re.sub(
r'''^mercurial\.\w+\.(\w+): (['"])(.*?)\2''',
r'\1: \3',
got2,
re.MULTILINE,
)
got2 = re.sub(r'^mercurial\.\w+\.(\w+): ', r'\1: ', got2, re.MULTILINE)
return any(
doctest.OutputChecker.check_output(self, w, g, optionflags)
for w, g in [(want, got), (want2, got2)]
)
def testmod(name, optionflags=0, testtarget=None):
__import__(name)
mod = sys.modules[name]
if testtarget is not None:
mod = getattr(mod, testtarget)
# minimal copy of doctest.testmod()
finder = doctest.DocTestFinder()
checker = None
if ispy3:
checker = py3docchecker()
runner = doctest.DocTestRunner(checker=checker, optionflags=optionflags)
for test in finder.find(mod, name):
runner.run(test)
runner.summarize()
DONT_RUN = []
# Exceptions to the defaults for a given detected module. The value for each
# module name is a list of dicts that specify the kwargs to pass to testmod.
# testmod is called once per item in the list, so an empty list will cause the
# module to not be tested.
testmod_arg_overrides = {
'i18n.check-translation': DONT_RUN, # may require extra installation
'mercurial.dagparser': [{'optionflags': doctest.NORMALIZE_WHITESPACE}],
'mercurial.keepalive': DONT_RUN, # >>> is an example, not a doctest
'mercurial.posix': DONT_RUN, # run by mercurial.platform
'mercurial.statprof': DONT_RUN, # >>> is an example, not a doctest
'mercurial.util': [{}, {'testtarget': 'platform'}], # run twice!
'mercurial.windows': DONT_RUN, # run by mercurial.platform
'tests.test-url': [{'optionflags': doctest.NORMALIZE_WHITESPACE}],
}
fileset = 'set:(**.py)'
cwd = os.path.dirname(os.environ["TESTDIR"])
if not os.path.isdir(os.path.join(cwd, ".hg")):
sys.exit(0)
files = subprocess.check_output(
"hg files --print0 \"%s\"" % fileset,
shell=True,
cwd=cwd,
).split(b'\0')
if sys.version_info[0] >= 3:
cwd = os.fsencode(cwd)
mods_tested = set()
for f in files:
if not f:
continue
with open(os.path.join(cwd, f), "rb") as fh:
if not re.search(br'\n\s*>>>', fh.read()):
continue
if ispy3:
f = f.decode()
modname = f.replace('.py', '').replace('\\', '.').replace('/', '.')
# Third-party modules aren't our responsibility to test, and the modules in
# contrib generally do not have doctests in a good state, plus they're hard
# to import if this test is running with py2, so we just skip both for now.
if modname.startswith('mercurial.thirdparty.') or modname.startswith(
'contrib.'
):
continue
for kwargs in testmod_arg_overrides.get(modname, [{}]):
mods_tested.add((modname, '%r' % (kwargs,)))
if modname.startswith('tests.'):
# On py2, we can't import from tests.foo, but it works on both py2
# and py3 with the way that PYTHONPATH is setup to import without
# the 'tests.' prefix, so we do that.
modname = modname[len('tests.') :]
testmod(modname, **kwargs)
# Meta-test: let's make sure that we actually ran what we expected to, above.
# Each item in the set is a 2-tuple of module name and stringified kwargs passed
# to testmod.
expected_mods_tested = set(
[
('hgext.convert.convcmd', '{}'),
('hgext.convert.cvsps', '{}'),
('hgext.convert.filemap', '{}'),
('hgext.convert.p4', '{}'),
('hgext.convert.subversion', '{}'),
('hgext.fix', '{}'),
('hgext.mq', '{}'),
('mercurial.changelog', '{}'),
('mercurial.cmdutil', '{}'),
('mercurial.color', '{}'),
('mercurial.dagparser', "{'optionflags': 4}"),
('mercurial.encoding', '{}'),
('mercurial.fancyopts', '{}'),
('mercurial.formatter', '{}'),
('mercurial.hg', '{}'),
('mercurial.hgweb.hgwebdir_mod', '{}'),
('mercurial.match', '{}'),
('mercurial.mdiff', '{}'),
('mercurial.minirst', '{}'),
('mercurial.parser', '{}'),
('mercurial.patch', '{}'),
('mercurial.pathutil', '{}'),
('mercurial.pycompat', '{}'),
('mercurial.revlogutils.deltas', '{}'),
('mercurial.revset', '{}'),
('mercurial.revsetlang', '{}'),
('mercurial.simplemerge', '{}'),
('mercurial.smartset', '{}'),
('mercurial.store', '{}'),
('mercurial.subrepo', '{}'),
('mercurial.templater', '{}'),
('mercurial.ui', '{}'),
('mercurial.util', "{'testtarget': 'platform'}"),
('mercurial.util', '{}'),
('mercurial.utils.dateutil', '{}'),
('mercurial.utils.stringutil', '{}'),
('mercurial.utils.urlutil', '{}'),
('tests.drawdag', '{}'),
('tests.test-run-tests', '{}'),
('tests.test-url', "{'optionflags': 4}"),
]
)
unexpectedly_run = mods_tested.difference(expected_mods_tested)
not_run = expected_mods_tested.difference(mods_tested)
if unexpectedly_run:
print('Unexpectedly ran (probably need to add to list):')
for r in sorted(unexpectedly_run):
print(' %r' % (r,))
if not_run:
print('Expected to run, but was not run (doctest removed?):')
for r in sorted(not_run):
print(' %r' % (r,))