revlog: add a C implementation of `headrevsdiff`
Python implementation of `headrevsdiff` can be very slow in the worst
case compared with the `heads` computation it replaces, since the
latter is done in C.
Even the average case of this Python implementation is still
noticeable in the profiles.
This patch makes the computation much much faster by doing it in C.
import os
from mercurial import (
commands,
extensions,
ui as uimod,
)
ignore = {b'highlight', b'win32text', b'factotum', b'beautifygraph'}
try:
import sqlite3
del sqlite3 # unused, just checking that import works
except ImportError:
ignore.add(b'sqlitestore')
if os.name != 'nt':
ignore.add(b'win32mbcs')
disabled = [ext for ext in extensions.disabled().keys() if ext not in ignore]
hgrc = open(os.environ["HGRCPATH"], 'wb')
hgrc.write(b'[extensions]\n')
for ext in disabled:
hgrc.write(ext + b'=\n')
hgrc.close()
u = uimod.ui.load()
extensions.loadall(u)
extensions.populateui(u)
globalshort = set()
globallong = set()
for option in commands.globalopts:
option[0] and globalshort.add(option[0])
option[1] and globallong.add(option[1])
for cmd, entry in commands.table.items():
seenshort = globalshort.copy()
seenlong = globallong.copy()
for option in entry[1]:
if (option[0] and option[0] in seenshort) or (
option[1] and option[1] in seenlong
):
print("command '" + cmd + "' has duplicate option " + str(option))
seenshort.add(option[0])
seenlong.add(option[1])