view tests/test-filecache.py @ 18338:384df4db6520

merge: merge file flags together with file content

The 'x' flag and the 'l' flag are very different. It is usually not a problem
to change the 'x' flag of a normal file independent of the content, but one
does not simply change the type of a file to 'l' independent of the content.

This removes the fmerge function that merged both 'x' and 'l' independent of
content early in the merge process. This correctly introduces some conflicts
instead of silent incorrect merges. 3-way flag merge will now be done in the
resolve process, right next to file content merge. Conflicts can thus be
resolved with (slightly inconvenient) resolve commands like 'resolve f --tool
internal:other'. It thus brings us closer to be able to re-solve manifest merge
after the merge and avoid prompts during merge.

This also removes the "conflicting flags for a - (n)one, e(x)ec or sym(l)ink?"
prompt that nobody could answer and that made it easy to mix symlink targets
and file contents up. Instead it will give a file merge where a sufficiently
clever merge tool can help resolving the issue.

import sys, os, subprocess

if subprocess.call(['python', '%s/hghave' % os.environ['TESTDIR'],
                    'cacheable']):
    sys.exit(80)

from mercurial import util, scmutil, extensions, hg, ui

filecache = scmutil.filecache

class fakerepo(object):
    def __init__(self):
        self._filecache = {}

    def join(self, p):
        return p

    def sjoin(self, p):
        return p

    @filecache('x')
    def cached(self):
        print 'creating'

    def invalidate(self):
        for k in self._filecache:
            try:
                delattr(self, k)
            except AttributeError:
                pass

def basic(repo):
    # file doesn't exist, calls function
    repo.cached

    repo.invalidate()
    # file still doesn't exist, uses cache
    repo.cached

    # create empty file
    f = open('x', 'w')
    f.close()
    repo.invalidate()
    # should recreate the object
    repo.cached

    f = open('x', 'w')
    f.write('a')
    f.close()
    repo.invalidate()
    # should recreate the object
    repo.cached

    repo.invalidate()
    # stats file again, nothing changed, reuses object
    repo.cached

    # atomic replace file, size doesn't change
    # hopefully st_mtime doesn't change as well so this doesn't use the cache
    # because of inode change
    f = scmutil.opener('.')('x', 'w', atomictemp=True)
    f.write('b')
    f.close()

    repo.invalidate()
    repo.cached

def fakeuncacheable():
    def wrapcacheable(orig, *args, **kwargs):
        return False

    def wrapinit(orig, *args, **kwargs):
        pass

    originit = extensions.wrapfunction(util.cachestat, '__init__', wrapinit)
    origcacheable = extensions.wrapfunction(util.cachestat, 'cacheable',
                                            wrapcacheable)

    try:
        os.remove('x')
    except OSError:
        pass

    basic(fakerepo())

    util.cachestat.cacheable = origcacheable
    util.cachestat.__init__ = originit

def test_filecache_synced():
    # test old behaviour that caused filecached properties to go out of sync
    os.system('hg init && echo a >> a && hg ci -qAm.')
    repo = hg.repository(ui.ui())
    # first rollback clears the filecache, but changelog to stays in __dict__
    repo.rollback()
    repo.commit('.')
    # second rollback comes along and touches the changelog externally
    # (file is moved)
    repo.rollback()
    # but since changelog isn't under the filecache control anymore, we don't
    # see that it changed, and return the old changelog without reconstructing
    # it
    repo.commit('.')

def setbeforeget(repo):
    os.remove('x')
    repo.cached = 0
    repo.invalidate()
    print repo.cached
    repo.invalidate()
    f = open('x', 'w')
    f.write('a')
    f.close()
    print repo.cached

print 'basic:'
print
basic(fakerepo())
print
print 'fakeuncacheable:'
print
fakeuncacheable()
test_filecache_synced()
print
print 'setbeforeget:'
print
setbeforeget(fakerepo())