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.
from mercurial import minifileset
def check(text, truecases, falsecases):
f = minifileset.compile(text)
for args in truecases:
if not f(*args):
print('unexpected: %r should include %r' % (text, args))
for args in falsecases:
if f(*args):
print('unexpected: %r should exclude %r' % (text, args))
check(b'all()', [(b'a.php', 123), (b'b.txt', 0)], [])
check(b'none()', [], [(b'a.php', 123), (b'b.txt', 0)])
check(b'!!!!((!(!!all())))', [], [(b'a.php', 123), (b'b.txt', 0)])
check(
b'"path:a" & (**.b | **.c)', [(b'a/b.b', 0), (b'a/c.c', 0)], [(b'b/c.c', 0)]
)
check(
b'(path:a & **.b) | **.c', [(b'a/b.b', 0), (b'a/c.c', 0), (b'b/c.c', 0)], []
)
check(
b'**.bin - size("<20B")', [(b'b.bin', 21)], [(b'a.bin', 11), (b'b.txt', 21)]
)
check(
b'!!**.bin or size(">20B") + "path:bin" or !size(">10")',
[(b'a.bin', 11), (b'b.txt', 21), (b'bin/abc', 11)],
[(b'a.notbin', 11), (b'b.txt', 11), (b'bin2/abc', 11)],
)
check(
b'(**.php and size(">10KB")) | **.zip | ("path:bin" & !"path:bin/README") '
b' | size(">1M")',
[(b'a.php', 15000), (b'a.zip', 0), (b'bin/a', 0), (b'bin/README', 1e7)],
[(b'a.php', 5000), (b'b.zip2', 0), (b't/bin/a', 0), (b'bin/README', 1)],
)