##// END OF EJS Templates
parsers: a C implementation of the new ancestors algorithm...
parsers: a C implementation of the new ancestors algorithm The performance of both the old and new Python ancestor algorithms depends on the number of revs they need to traverse. Although the new algorithm performs far better than the old when revs are numerically and topologically close, both algorithms become slow under other circumstances, taking up to 1.8 seconds to give answers in a Linux kernel repo. This C implementation of the new algorithm is a fairly straightforward transliteration. The only corner case of interest is that it raises an OverflowError if the number of GCA candidates found during the first pass is greater than 24, to avoid the dual perils of fixnum overflow and trying to allocate too much memory. (If this exception is raised, the Python implementation is used instead.) Performance numbers are good: in a Linux kernel repo, time for "hg debugancestors" on two distant revs (24bf01de7537 and c2a8808f5943) is as follows: Old Python: 0.36 sec New Python: 0.42 sec New C: 0.02 sec For a case where the new algorithm should perform well: Old Python: 1.84 sec New Python: 0.07 sec New C: measures as zero when using --time (This commit includes a paranoid cross-check to ensure that the Python and C implementations give identical answers. The above performance numbers were measured with that check disabled.)

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formatter.py
80 lines | 2.8 KiB | text/x-python | PythonLexer
# formatter.py - generic output formatting for mercurial
#
# Copyright 2012 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
class baseformatter(object):
def __init__(self, ui, topic, opts):
self._ui = ui
self._topic = topic
self._style = opts.get("style")
self._template = opts.get("template")
self._item = None
def __bool__(self):
'''return False if we're not doing real templating so we can
skip extra work'''
return True
def _showitem(self):
'''show a formatted item once all data is collected'''
pass
def startitem(self):
'''begin an item in the format list'''
if self._item is not None:
self._showitem()
self._item = {}
def data(self, **data):
'''insert data into item that's not shown in default output'''
self._item.update(data)
def write(self, fields, deftext, *fielddata, **opts):
'''do default text output while assigning data to item'''
for k, v in zip(fields.split(), fielddata):
self._item[k] = v
def condwrite(self, cond, fields, deftext, *fielddata, **opts):
'''do conditional write (primarily for plain formatter)'''
for k, v in zip(fields.split(), fielddata):
self._item[k] = v
def plain(self, text, **opts):
'''show raw text for non-templated mode'''
pass
def end(self):
'''end output for the formatter'''
if self._item is not None:
self._showitem()
class plainformatter(baseformatter):
'''the default text output scheme'''
def __init__(self, ui, topic, opts):
baseformatter.__init__(self, ui, topic, opts)
def __bool__(self):
return False
def startitem(self):
pass
def data(self, **data):
pass
def write(self, fields, deftext, *fielddata, **opts):
self._ui.write(deftext % fielddata, **opts)
def condwrite(self, cond, fields, deftext, *fielddata, **opts):
'''do conditional write'''
if cond:
self._ui.write(deftext % fielddata, **opts)
def plain(self, text, **opts):
self._ui.write(text, **opts)
def end(self):
pass
class debugformatter(baseformatter):
def __init__(self, ui, topic, opts):
baseformatter.__init__(self, ui, topic, opts)
self._ui.write("%s = {\n" % self._topic)
def _showitem(self):
self._ui.write(" " + repr(self._item) + ",\n")
def end(self):
baseformatter.end(self)
self._ui.write("}\n")
def formatter(ui, topic, opts):
if ui.configbool('ui', 'formatdebug'):
return debugformatter(ui, topic, opts)
return plainformatter(ui, topic, opts)