branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
import os
import sys
from mercurial import dispatch
def printb(data, end=b'\n'):
out = getattr(sys.stdout, 'buffer', sys.stdout)
out.write(data + end)
out.flush()
def testdispatch(cmd):
"""Simple wrapper around dispatch.dispatch()
Prints command and result value, but does not handle quoting.
"""
printb(b"running: %s" % (cmd,))
req = dispatch.request(cmd.split())
result = dispatch.dispatch(req)
printb(b"result: %r" % (result,))
testdispatch(b"init test1")
os.chdir('test1')
# create file 'foo', add and commit
f = open('foo', 'wb')
f.write(b'foo\n')
f.close()
testdispatch(b"add foo")
testdispatch(b"commit -m commit1 -d 2000-01-01 foo")
# append to file 'foo' and commit
f = open('foo', 'ab')
f.write(b'bar\n')
f.close()
testdispatch(b"commit -m commit2 -d 2000-01-02 foo")
# check 88803a69b24 (fancyopts modified command table)
testdispatch(b"log -r 0")
testdispatch(b"log -r tip")