branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
import os
import winreg # pytype: disable=import-error
from typing import (
List,
TYPE_CHECKING,
Tuple,
)
from . import (
encoding,
pycompat,
util,
win32,
)
if TYPE_CHECKING:
from . import ui as uimod
# MS-DOS 'more' is the only pager available by default on Windows.
fallbackpager = b'more'
def systemrcpath() -> List[bytes]:
'''return default os-specific hgrc search path'''
rcpath = []
filename = win32.executablepath()
# Use mercurial.ini found in directory with hg.exe
progrc = os.path.join(os.path.dirname(filename), b'mercurial.ini')
rcpath.append(progrc)
def _processdir(progrcd: bytes) -> None:
if os.path.isdir(progrcd):
for f, kind in sorted(util.listdir(progrcd)):
if f.endswith(b'.rc'):
rcpath.append(os.path.join(progrcd, f))
# Use hgrc.d found in directory with hg.exe
_processdir(os.path.join(os.path.dirname(filename), b'hgrc.d'))
# treat a PROGRAMDATA directory as equivalent to /etc/mercurial
programdata = encoding.environ.get(b'PROGRAMDATA')
if programdata:
programdata = os.path.join(programdata, b'Mercurial')
_processdir(os.path.join(programdata, b'hgrc.d'))
ini = os.path.join(programdata, b'mercurial.ini')
if os.path.isfile(ini):
rcpath.append(ini)
ini = os.path.join(programdata, b'hgrc')
if os.path.isfile(ini):
rcpath.append(ini)
# next look for a system rcpath in the registry
value = util.lookupreg(
# pytype: disable=module-attr
b'SOFTWARE\\Mercurial',
None,
winreg.HKEY_LOCAL_MACHINE
# pytype: enable=module-attr
)
if value and isinstance(value, bytes):
value = util.localpath(value)
for p in value.split(pycompat.ospathsep):
if p.lower().endswith(b'mercurial.ini'):
rcpath.append(p)
else:
_processdir(p)
return rcpath
def userrcpath() -> List[bytes]:
'''return os-specific hgrc search path to the user dir'''
home = _legacy_expanduser(b'~')
path = [os.path.join(home, b'mercurial.ini'), os.path.join(home, b'.hgrc')]
userprofile = encoding.environ.get(b'USERPROFILE')
if userprofile and userprofile != home:
path.append(os.path.join(userprofile, b'mercurial.ini'))
path.append(os.path.join(userprofile, b'.hgrc'))
return path
def _legacy_expanduser(path: bytes) -> bytes:
"""Expand ~ and ~user constructs in the pre 3.8 style"""
# Python 3.8+ changed the expansion of '~' from HOME to USERPROFILE. See
# https://bugs.python.org/issue36264. It also seems to capitalize the drive
# letter, as though it was processed through os.path.realpath().
if not path.startswith(b'~'):
return path
i, n = 1, len(path)
while i < n and path[i] not in b'\\/':
i += 1
if b'HOME' in encoding.environ:
userhome = encoding.environ[b'HOME']
elif b'USERPROFILE' in encoding.environ:
userhome = encoding.environ[b'USERPROFILE']
elif b'HOMEPATH' not in encoding.environ:
return path
else:
try:
drive = encoding.environ[b'HOMEDRIVE']
except KeyError:
drive = b''
userhome = os.path.join(drive, encoding.environ[b'HOMEPATH'])
if i != 1: # ~user
userhome = os.path.join(os.path.dirname(userhome), path[1:i])
return userhome + path[i:]
def termsize(ui: "uimod.ui") -> Tuple[int, int]:
return win32.termsize()