tests/test-filelog.py

rhg: desambiguate status without decompressing filelog if possible

When status is unsure based on `stat()` and the dirstate if a file is clean
or modified, we need to compare it against the filelog.

This comparison can skip looking at contents if the lengths differ.
This changeset optimize this further to deduce what we can about the length
if the filelog without decompressing it or resolving deltas.

Differential Revision: https://phab.mercurial-scm.org/D11965

#!/usr/bin/env python
"""
Tests the behavior of filelog w.r.t. data starting with '\1\n'
"""
from __future__ import absolute_import, print_function

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.')