tests/test-symlink-os-yes-fs-no.py

merge: before cd/dc prompt, check that changed side really changed

Before, merging would in some cases ask "wrong" questions about
"changed/deleted" conflicts ... and even do it before the resolve phase where
they can be postponed, re"resolved" or answered in bulk operations.

Instead, check that the content of the changed file really did change.

Reading and comparing file content is expensive and should be avoided before
the resolve phase. Prompting the user is however even more expensive. Checking
the content here is thus better.

The 'f in ancestors[0]' should not be necessary but is included to be extra
safe.

import os, sys, time
from mercurial import hg, ui, commands, util

TESTDIR = os.environ["TESTDIR"]
BUNDLEPATH = os.path.join(TESTDIR, 'bundles', 'test-no-symlinks.hg')

# only makes sense to test on os which supports symlinks
if not getattr(os, "symlink", False):
    sys.exit(80) # SKIPPED_STATUS defined in run-tests.py

u = ui.ui()
# hide outer repo
hg.peer(u, {}, '.', create=True)

# clone with symlink support
hg.clone(u, {}, BUNDLEPATH, 'test0')

repo = hg.repository(u, 'test0')

# wait a bit, or the status call wont update the dirstate
time.sleep(1)
commands.status(u, repo)

# now disable symlink support -- this is what os.symlink would do on a
# non-symlink file system
def symlink_failure(src, dst):
    raise OSError(1, "Operation not permitted")
os.symlink = symlink_failure

# dereference links as if a Samba server has exported this to a
# Windows client
for f in 'test0/a.lnk', 'test0/d/b.lnk':
    os.unlink(f)
    fp = open(f, 'wb')
    fp.write(util.readfile(f[:-4]))
    fp.close()

# reload repository
u = ui.ui()
repo = hg.repository(u, 'test0')
commands.status(u, repo)

# try cloning a repo which contains symlinks
u = ui.ui()
hg.clone(u, {}, BUNDLEPATH, 'test1')