debug-discovery: also gather details on tree-discovery queries type
This is useful to understand the algorithm.
# state.py - writing and reading state files in Mercurial
#
# Copyright 2018 Pulkit Goyal <pulkitmgoyal@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""
This file contains class to wrap the state for commands and other
related logic.
All the data related to the command state is stored as dictionary in the object.
The class has methods using which the data can be stored to disk in a file under
.hg/ directory.
We store the data on disk in cbor, for which we use the CBOR format to encode
the data.
"""
import contextlib
from .i18n import _
from . import (
error,
pycompat,
util,
)
from .utils import cborutil
if pycompat.TYPE_CHECKING:
from typing import (
Any,
Dict,
)
for t in (Any, Dict):
assert t
class cmdstate:
"""a wrapper class to store the state of commands like `rebase`, `graft`,
`histedit`, `shelve` etc. Extensions can also use this to write state files.
All the data for the state is stored in the form of key-value pairs in a
dictionary.
The class object can write all the data to a file in .hg/ directory and
can populate the object data reading that file.
Uses cbor to serialize and deserialize data while writing and reading from
disk.
"""
def __init__(self, repo, fname):
"""repo is the repo object
fname is the file name in which data should be stored in .hg directory
"""
self._repo = repo
self.fname = fname
def read(self):
# type: () -> Dict[bytes, Any]
"""read the existing state file and return a dict of data stored"""
return self._read()
def save(self, version, data):
"""write all the state data stored to .hg/<filename> file
we use third-party library cbor to serialize data to write in the file.
"""
if not isinstance(version, int):
raise error.ProgrammingError(
b"version of state file should be an integer"
)
with self._repo.vfs(self.fname, b'wb', atomictemp=True) as fp:
fp.write(b'%d\n' % version)
for chunk in cborutil.streamencode(data):
fp.write(chunk)
def _read(self):
"""reads the state file and returns a dictionary which contain
data in the same format as it was before storing"""
with self._repo.vfs(self.fname, b'rb') as fp:
try:
int(fp.readline())
except ValueError:
raise error.CorruptedState(
b"unknown version of state file found"
)
return cborutil.decodeall(fp.read())[0]
def delete(self):
"""drop the state file if exists"""
util.unlinkpath(self._repo.vfs.join(self.fname), ignoremissing=True)
def exists(self):
"""check whether the state file exists or not"""
return self._repo.vfs.exists(self.fname)
class _statecheck:
"""a utility class that deals with multistep operations like graft,
histedit, bisect, update etc and check whether such commands
are in an unfinished conditition or not and return appropriate message
and hint.
It also has the ability to register and determine the states of any new
multistep operation or multistep command extension.
"""
def __init__(
self,
opname,
fname,
clearable,
allowcommit,
reportonly,
continueflag,
stopflag,
childopnames,
cmdmsg,
cmdhint,
statushint,
abortfunc,
continuefunc,
):
self._opname = opname
self._fname = fname
self._clearable = clearable
self._allowcommit = allowcommit
self._reportonly = reportonly
self._continueflag = continueflag
self._stopflag = stopflag
self._childopnames = childopnames
self._delegating = False
self._cmdmsg = cmdmsg
self._cmdhint = cmdhint
self._statushint = statushint
self.abortfunc = abortfunc
self.continuefunc = continuefunc
def statusmsg(self):
"""returns the hint message corresponding to the command for
hg status --verbose
"""
if not self._statushint:
hint = _(
b'To continue: hg %s --continue\n'
b'To abort: hg %s --abort'
) % (self._opname, self._opname)
if self._stopflag:
hint = hint + (
_(b'\nTo stop: hg %s --stop') % (self._opname)
)
return hint
return self._statushint
def hint(self):
"""returns the hint message corresponding to an interrupted
operation
"""
if not self._cmdhint:
if not self._stopflag:
return _(b"use 'hg %s --continue' or 'hg %s --abort'") % (
self._opname,
self._opname,
)
else:
return _(
b"use 'hg %s --continue', 'hg %s --abort', "
b"or 'hg %s --stop'"
) % (
self._opname,
self._opname,
self._opname,
)
return self._cmdhint
def msg(self):
"""returns the status message corresponding to the command"""
if not self._cmdmsg:
return _(b'%s in progress') % (self._opname)
return self._cmdmsg
def continuemsg(self):
"""returns appropriate continue message corresponding to command"""
return _(b'hg %s --continue') % (self._opname)
def isunfinished(self, repo):
"""determines whether a multi-step operation is in progress
or not
"""
if self._opname == b'merge':
return len(repo[None].parents()) > 1
elif self._delegating:
return False
else:
return repo.vfs.exists(self._fname)
# A list of statecheck objects for multistep operations like graft.
_unfinishedstates = []
_unfinishedstatesbyname = {}
def addunfinished(
opname,
fname,
clearable=False,
allowcommit=False,
reportonly=False,
continueflag=False,
stopflag=False,
childopnames=None,
cmdmsg=b"",
cmdhint=b"",
statushint=b"",
abortfunc=None,
continuefunc=None,
):
"""this registers a new command or operation to unfinishedstates
opname is the name the command or operation
fname is the file name in which data should be stored in .hg directory.
It is None for merge command.
clearable boolean determines whether or not interrupted states can be
cleared by running `hg update -C .` which in turn deletes the
state file.
allowcommit boolean decides whether commit is allowed during interrupted
state or not.
reportonly flag is used for operations like bisect where we just
need to detect the operation using 'hg status --verbose'
continueflag is a boolean determines whether or not a command supports
`--continue` option or not.
stopflag is a boolean that determines whether or not a command supports
--stop flag
childopnames is a list of other opnames this op uses as sub-steps of its
own execution. They must already be added.
cmdmsg is used to pass a different status message in case standard
message of the format "abort: cmdname in progress" is not desired.
cmdhint is used to pass a different hint message in case standard
message of the format "To continue: hg cmdname --continue
To abort: hg cmdname --abort" is not desired.
statushint is used to pass a different status message in case standard
message of the format ('To continue: hg cmdname --continue'
'To abort: hg cmdname --abort') is not desired
abortfunc stores the function required to abort an unfinished state.
continuefunc stores the function required to finish an interrupted
operation.
"""
childopnames = childopnames or []
statecheckobj = _statecheck(
opname,
fname,
clearable,
allowcommit,
reportonly,
continueflag,
stopflag,
childopnames,
cmdmsg,
cmdhint,
statushint,
abortfunc,
continuefunc,
)
if opname == b'merge':
_unfinishedstates.append(statecheckobj)
else:
# This check enforces that for any op 'foo' which depends on op 'bar',
# 'foo' comes before 'bar' in _unfinishedstates. This ensures that
# getrepostate() always returns the most specific applicable answer.
for childopname in childopnames:
if childopname not in _unfinishedstatesbyname:
raise error.ProgrammingError(
_(b'op %s depends on unknown op %s') % (opname, childopname)
)
_unfinishedstates.insert(0, statecheckobj)
if opname in _unfinishedstatesbyname:
raise error.ProgrammingError(_(b'op %s registered twice') % opname)
_unfinishedstatesbyname[opname] = statecheckobj
def _getparentandchild(opname, childopname):
p = _unfinishedstatesbyname.get(opname, None)
if not p:
raise error.ProgrammingError(_(b'unknown op %s') % opname)
if childopname not in p._childopnames:
raise error.ProgrammingError(
_(b'op %s does not delegate to %s') % (opname, childopname)
)
c = _unfinishedstatesbyname[childopname]
return p, c
@contextlib.contextmanager
def delegating(repo, opname, childopname):
"""context wrapper for delegations from opname to childopname.
requires that childopname was specified when opname was registered.
Usage:
def my_command_foo_that_uses_rebase(...):
...
with state.delegating(repo, 'foo', 'rebase'):
_run_rebase(...)
...
"""
p, c = _getparentandchild(opname, childopname)
if p._delegating:
raise error.ProgrammingError(
_(b'cannot delegate from op %s recursively') % opname
)
p._delegating = True
try:
yield
except error.ConflictResolutionRequired as e:
# Rewrite conflict resolution advice for the parent opname.
if e.opname == childopname:
raise error.ConflictResolutionRequired(opname)
raise e
finally:
p._delegating = False
def ischildunfinished(repo, opname, childopname):
"""Returns true if both opname and childopname are unfinished."""
p, c = _getparentandchild(opname, childopname)
return (p._delegating or p.isunfinished(repo)) and c.isunfinished(repo)
def continuechild(ui, repo, opname, childopname):
"""Checks that childopname is in progress, and continues it."""
p, c = _getparentandchild(opname, childopname)
if not ischildunfinished(repo, opname, childopname):
raise error.ProgrammingError(
_(b'child op %s of parent %s is not unfinished')
% (childopname, opname)
)
if not c.continuefunc:
raise error.ProgrammingError(
_(b'op %s has no continue function') % childopname
)
return c.continuefunc(ui, repo)
addunfinished(
b'update',
fname=b'updatestate',
clearable=True,
cmdmsg=_(b'last update was interrupted'),
cmdhint=_(b"use 'hg update' to get a consistent checkout"),
statushint=_(b"To continue: hg update ."),
)
addunfinished(
b'bisect',
fname=b'bisect.state',
allowcommit=True,
reportonly=True,
statushint=_(
b'To mark the changeset good: hg bisect --good\n'
b'To mark the changeset bad: hg bisect --bad\n'
b'To abort: hg bisect --reset\n'
),
)
def getrepostate(repo):
# experimental config: commands.status.skipstates
skip = set(repo.ui.configlist(b'commands', b'status.skipstates'))
for state in _unfinishedstates:
if state._opname in skip:
continue
if state.isunfinished(repo):
return (state._opname, state.statusmsg())