branchcache: skip entries that are topological heads in the on disk file
In the majority of cases, topological heads are also branch heads. We have
efficient way to get the topological heads and efficient way to retrieve
their branch information. So there is little value in putting them in the branch
cache file explicitly. On the contrary, writing them explicitly tend to create
very large cache file that are inefficient to read and update.
So the branch cache v3 format is no longer including them. This changeset focus
on the format aspect and have no focus on the performance aspect. We will cover
that later.
#!/usr/bin/env python
"""
Tests the behavior of filelog w.r.t. data starting with '\1\n'
"""
from mercurial.node import hex
from mercurial import (
hg,
ui as uimod,
)
myui = uimod.ui.load()
repo = hg.repository(myui, path=b'.', create=True)
fl = repo.file(b'foobar')
def addrev(text, renamed=False):
if renamed:
# data doesn't matter. Just make sure filelog.renamed() returns True
meta = {b'copyrev': hex(repo.nullid), b'copy': b'bar'}
else:
meta = {}
lock = t = None
try:
lock = repo.lock()
t = repo.transaction(b'commit')
node = fl.add(text, meta, t, 0, repo.nullid, repo.nullid)
return node
finally:
if t:
t.close()
if lock:
lock.release()
def error(text):
print('ERROR: ' + text)
textwith = b'\1\nfoo'
without = b'foo'
node = addrev(textwith)
if not textwith == fl.read(node):
error('filelog.read for data starting with \\1\\n')
if fl.cmp(node, textwith) or not fl.cmp(node, without):
error('filelog.cmp for data starting with \\1\\n')
if fl.size(0) != len(textwith):
error(
'FIXME: This is a known failure of filelog.size for data starting '
'with \\1\\n'
)
node = addrev(textwith, renamed=True)
if not textwith == fl.read(node):
error('filelog.read for a renaming + data starting with \\1\\n')
if fl.cmp(node, textwith) or not fl.cmp(node, without):
error('filelog.cmp for a renaming + data starting with \\1\\n')
if fl.size(1) != len(textwith):
error('filelog.size for a renaming + data starting with \\1\\n')
print('OK.')