view tests/blackbox-readonly-dispatch.py @ 44333:50ad851efd9b

nodemap: introduce append-only incremental update of the persistent data

Rewriting the full nodemap for each transaction has a cost we would like to
avoid. We introduce a new way to write persistent nodemap data by adding new
information at the end for file. Any new and updated block as added at the end
of the file. The last block is the new root node.

With this method, some of the block already on disk get "dereferenced" and
become dead data. In later changesets, We'll start tracking the amount of dead
data to eventually re-generate a full nodemap.

Differential Revision: https://phab.mercurial-scm.org/D7886

from __future__ import absolute_import
import os
from mercurial import (
    dispatch,
    extensions,
    ui as uimod,
)


def testdispatch(cmd):
    """Simple wrapper around dispatch.dispatch()

    Prints command and result value, but does not handle quoting.
    """
    ui = uimod.ui.load()
    extensions.populateui(ui)
    ui.statusnoi18n(b"running: %s\n" % cmd)
    req = dispatch.request(cmd.split(), ui)
    result = dispatch.dispatch(req)
    ui.statusnoi18n(b"result: %r\n" % result)


# create file 'foo', add and commit
f = open(b'foo', 'wb')
f.write(b'foo\n')
f.close()
testdispatch(b"--debug add foo")
testdispatch(b"--debug commit -m commit1 -d 2000-01-01 foo")

# append to file 'foo' and commit
f = open(b'foo', 'ab')
f.write(b'bar\n')
f.close()
# remove blackbox.log directory (proxy for readonly log file)
os.rmdir(b".hg/blackbox.log")
# replace it with the real blackbox.log file
os.rename(b".hg/blackbox.log-", b".hg/blackbox.log")
testdispatch(b"--debug commit -m commit2 -d 2000-01-02 foo")

# check 88803a69b24 (fancyopts modified command table)
testdispatch(b"--debug log -r 0")
testdispatch(b"--debug log -r tip")