tests/test-filelog.py

context: introduce merge.preferancestor for controlling which ancestor to pick

Multiple revisions can be specified in merge.preferancestor, separated by
whitespace. First match wins.

This makes it possible to overrule the default of picking the common ancestor
with the lowest hash value among the "best" (introduced in 3605d4e7e618).

This can for instance help with some merges where the 'wrong' ancestor is used.
There will thus be some overlap between this and the problems that can be
solved with a future 'consensus merge'.

Mercurial will show a note like
  note: using 40663881a6dd as ancestor of 3b08d01b0ab5 and adfe50279922
        alternatively, use --config merge.preferancestor=0f6b37dbe527
when the option is available, listing all the alternative ancestors.

#!/usr/bin/env python
"""
Tests the behaviour of filelog w.r.t. data starting with '\1\n'
"""
from mercurial import ui, hg
from mercurial.node import nullid, hex

myui = ui.ui()
repo = hg.repository(myui, path='.', create=True)

fl = repo.file('foobar')

def addrev(text, renamed=False):
    if renamed:
        # data doesn't matter. Just make sure filelog.renamed() returns True
        meta = {'copyrev': hex(nullid), 'copy': 'bar'}
    else:
        meta = {}

    lock = t = None
    try:
        lock = repo.lock()
        t = repo.transaction('commit')
        node = fl.add(text, meta, t, 0, nullid, nullid)
        return node
    finally:
        if t:
            t.close()
        if lock:
            lock.release()

def error(text):
    print 'ERROR: ' + text

textwith = '\1\nfoo'
without = '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.'