extensions: add detailed loading information
This lets you track down what exactly is happening during extension loading,
and how long various steps took.
# extensions.py - extension handling for mercurial
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import ast
import collections
import functools
import imp
import inspect
import os
from .i18n import (
_,
gettext,
)
from . import (
cmdutil,
configitems,
error,
pycompat,
util,
)
from .utils import (
stringutil,
)
_extensions = {}
_disabledextensions = {}
_aftercallbacks = {}
_order = []
_builtin = {
'hbisect',
'bookmarks',
'color',
'parentrevspec',
'progress',
'interhg',
'inotify',
'hgcia'
}
def extensions(ui=None):
if ui:
def enabled(name):
for format in ['%s', 'hgext.%s']:
conf = ui.config('extensions', format % name)
if conf is not None and not conf.startswith('!'):
return True
else:
enabled = lambda name: True
for name in _order:
module = _extensions[name]
if module and enabled(name):
yield name, module
def find(name):
'''return module with given extension name'''
mod = None
try:
mod = _extensions[name]
except KeyError:
for k, v in _extensions.iteritems():
if k.endswith('.' + name) or k.endswith('/' + name):
mod = v
break
if not mod:
raise KeyError(name)
return mod
def loadpath(path, module_name):
module_name = module_name.replace('.', '_')
path = util.normpath(util.expandpath(path))
module_name = pycompat.fsdecode(module_name)
path = pycompat.fsdecode(path)
if os.path.isdir(path):
# module/__init__.py style
d, f = os.path.split(path)
fd, fpath, desc = imp.find_module(f, [d])
return imp.load_module(module_name, fd, fpath, desc)
else:
try:
return imp.load_source(module_name, path)
except IOError as exc:
if not exc.filename:
exc.filename = path # python does not fill this
raise
def _importh(name):
"""import and return the <name> module"""
mod = __import__(pycompat.sysstr(name))
components = name.split('.')
for comp in components[1:]:
mod = getattr(mod, comp)
return mod
def _importext(name, path=None, reportfunc=None):
if path:
# the module will be loaded in sys.modules
# choose an unique name so that it doesn't
# conflicts with other modules
mod = loadpath(path, 'hgext.%s' % name)
else:
try:
mod = _importh("hgext.%s" % name)
except ImportError as err:
if reportfunc:
reportfunc(err, "hgext.%s" % name, "hgext3rd.%s" % name)
try:
mod = _importh("hgext3rd.%s" % name)
except ImportError as err:
if reportfunc:
reportfunc(err, "hgext3rd.%s" % name, name)
mod = _importh(name)
return mod
def _reportimporterror(ui, err, failed, next):
# note: this ui.debug happens before --debug is processed,
# Use --config ui.debug=1 to see them.
if ui.configbool('devel', 'debug.extensions'):
ui.debug('debug.extensions: - could not import %s (%s): trying %s\n'
% (failed, stringutil.forcebytestr(err), next))
if ui.debugflag:
ui.traceback()
def _rejectunicode(name, xs):
if isinstance(xs, (list, set, tuple)):
for x in xs:
_rejectunicode(name, x)
elif isinstance(xs, dict):
for k, v in xs.items():
_rejectunicode(name, k)
_rejectunicode(b'%s.%s' % (name, stringutil.forcebytestr(k)), v)
elif isinstance(xs, type(u'')):
raise error.ProgrammingError(b"unicode %r found in %s" % (xs, name),
hint="use b'' to make it byte string")
# attributes set by registrar.command
_cmdfuncattrs = ('norepo', 'optionalrepo', 'inferrepo')
def _validatecmdtable(ui, cmdtable):
"""Check if extension commands have required attributes"""
for c, e in cmdtable.iteritems():
f = e[0]
missing = [a for a in _cmdfuncattrs if not util.safehasattr(f, a)]
if not missing:
continue
raise error.ProgrammingError(
'missing attributes: %s' % ', '.join(missing),
hint="use @command decorator to register '%s'" % c)
def _validatetables(ui, mod):
"""Sanity check for loadable tables provided by extension module"""
for t in ['cmdtable', 'colortable', 'configtable']:
_rejectunicode(t, getattr(mod, t, {}))
for t in ['filesetpredicate', 'internalmerge', 'revsetpredicate',
'templatefilter', 'templatefunc', 'templatekeyword']:
o = getattr(mod, t, None)
if o:
_rejectunicode(t, o._table)
_validatecmdtable(ui, getattr(mod, 'cmdtable', {}))
def load(ui, name, path, log=lambda *a: None):
if name.startswith('hgext.') or name.startswith('hgext/'):
shortname = name[6:]
else:
shortname = name
if shortname in _builtin:
return None
if shortname in _extensions:
return _extensions[shortname]
log(' - loading extension: %r\n', shortname)
_extensions[shortname] = None
with util.timedcm() as stats:
mod = _importext(name, path, bind(_reportimporterror, ui))
log(' > %r extension loaded in %s\n', shortname, stats)
# Before we do anything with the extension, check against minimum stated
# compatibility. This gives extension authors a mechanism to have their
# extensions short circuit when loaded with a known incompatible version
# of Mercurial.
minver = getattr(mod, 'minimumhgversion', None)
if minver and util.versiontuple(minver, 2) > util.versiontuple(n=2):
ui.warn(_('(third party extension %s requires version %s or newer '
'of Mercurial; disabling)\n') % (shortname, minver))
return
log(' - validating extension tables: %r\n', shortname)
_validatetables(ui, mod)
_extensions[shortname] = mod
_order.append(shortname)
log(' - invoking registered callbacks: %r\n', shortname)
with util.timedcm() as stats:
for fn in _aftercallbacks.get(shortname, []):
fn(loaded=True)
log(' > callbacks completed in %s\n', stats)
return mod
def _runuisetup(name, ui):
uisetup = getattr(_extensions[name], 'uisetup', None)
if uisetup:
try:
uisetup(ui)
except Exception as inst:
ui.traceback(force=True)
msg = stringutil.forcebytestr(inst)
ui.warn(_("*** failed to set up extension %s: %s\n") % (name, msg))
return False
return True
def _runextsetup(name, ui):
extsetup = getattr(_extensions[name], 'extsetup', None)
if extsetup:
try:
try:
extsetup(ui)
except TypeError:
if pycompat.getargspec(extsetup).args:
raise
extsetup() # old extsetup with no ui argument
except Exception as inst:
ui.traceback(force=True)
msg = stringutil.forcebytestr(inst)
ui.warn(_("*** failed to set up extension %s: %s\n") % (name, msg))
return False
return True
def loadall(ui, whitelist=None):
if ui.configbool('devel', 'debug.extensions'):
log = lambda msg, *values: ui.debug('debug.extensions: ',
msg % values, label='debug.extensions')
else:
log = lambda *a, **kw: None
result = ui.configitems("extensions")
if whitelist is not None:
result = [(k, v) for (k, v) in result if k in whitelist]
newindex = len(_order)
log('loading %sextensions\n', 'additional ' if newindex else '')
log('- processing %d entries\n', len(result))
with util.timedcm() as stats:
for (name, path) in result:
if path:
if path[0:1] == '!':
if name not in _disabledextensions:
log(' - skipping disabled extension: %r\n', name)
_disabledextensions[name] = path[1:]
continue
try:
load(ui, name, path, log)
except Exception as inst:
msg = stringutil.forcebytestr(inst)
if path:
ui.warn(_("*** failed to import extension %s from %s: %s\n")
% (name, path, msg))
else:
ui.warn(_("*** failed to import extension %s: %s\n")
% (name, msg))
if isinstance(inst, error.Hint) and inst.hint:
ui.warn(_("*** (%s)\n") % inst.hint)
ui.traceback()
log('> loaded %d extensions, total time %s\n',
len(_order) - newindex, stats)
# list of (objname, loadermod, loadername) tuple:
# - objname is the name of an object in extension module,
# from which extra information is loaded
# - loadermod is the module where loader is placed
# - loadername is the name of the function,
# which takes (ui, extensionname, extraobj) arguments
#
# This one is for the list of item that must be run before running any setup
earlyextraloaders = [
('configtable', configitems, 'loadconfigtable'),
]
log('- loading configtable attributes\n')
_loadextra(ui, newindex, earlyextraloaders)
broken = set()
log('- executing uisetup hooks\n')
for name in _order[newindex:]:
log(' - running uisetup for %r\n', name)
with util.timedcm() as stats:
if not _runuisetup(name, ui):
log(' - the %r extension uisetup failed\n', name)
broken.add(name)
log(' > uisetup for %r took %s\n', name, stats)
log('- executing extsetup hooks\n')
for name in _order[newindex:]:
if name in broken:
continue
log(' - running extsetup for %r\n', name)
with util.timedcm() as stats:
if not _runextsetup(name, ui):
log(' - the %r extension extsetup failed\n', name)
broken.add(name)
log(' > extsetup for %r took %s\n', name, stats)
for name in broken:
log(' - disabling broken %r extension\n', name)
_extensions[name] = None
# Call aftercallbacks that were never met.
log('- executing remaining aftercallbacks\n')
with util.timedcm() as stats:
for shortname in _aftercallbacks:
if shortname in _extensions:
continue
for fn in _aftercallbacks[shortname]:
log(' - extension %r not loaded, notify callbacks\n',
shortname)
fn(loaded=False)
log('> remaining aftercallbacks completed in %s\n', stats)
# loadall() is called multiple times and lingering _aftercallbacks
# entries could result in double execution. See issue4646.
_aftercallbacks.clear()
# delay importing avoids cyclic dependency (especially commands)
from . import (
color,
commands,
filemerge,
fileset,
revset,
templatefilters,
templatefuncs,
templatekw,
)
# list of (objname, loadermod, loadername) tuple:
# - objname is the name of an object in extension module,
# from which extra information is loaded
# - loadermod is the module where loader is placed
# - loadername is the name of the function,
# which takes (ui, extensionname, extraobj) arguments
log('- loading extension registration objects\n')
extraloaders = [
('cmdtable', commands, 'loadcmdtable'),
('colortable', color, 'loadcolortable'),
('filesetpredicate', fileset, 'loadpredicate'),
('internalmerge', filemerge, 'loadinternalmerge'),
('revsetpredicate', revset, 'loadpredicate'),
('templatefilter', templatefilters, 'loadfilter'),
('templatefunc', templatefuncs, 'loadfunction'),
('templatekeyword', templatekw, 'loadkeyword'),
]
with util.timedcm() as stats:
_loadextra(ui, newindex, extraloaders)
log('> extension registration object loading took %s\n', stats)
log('extension loading complete\n')
def _loadextra(ui, newindex, extraloaders):
for name in _order[newindex:]:
module = _extensions[name]
if not module:
continue # loading this module failed
for objname, loadermod, loadername in extraloaders:
extraobj = getattr(module, objname, None)
if extraobj is not None:
getattr(loadermod, loadername)(ui, name, extraobj)
def afterloaded(extension, callback):
'''Run the specified function after a named extension is loaded.
If the named extension is already loaded, the callback will be called
immediately.
If the named extension never loads, the callback will be called after
all extensions have been loaded.
The callback receives the named argument ``loaded``, which is a boolean
indicating whether the dependent extension actually loaded.
'''
if extension in _extensions:
# Report loaded as False if the extension is disabled
loaded = (_extensions[extension] is not None)
callback(loaded=loaded)
else:
_aftercallbacks.setdefault(extension, []).append(callback)
def bind(func, *args):
'''Partial function application
Returns a new function that is the partial application of args and kwargs
to func. For example,
f(1, 2, bar=3) === bind(f, 1)(2, bar=3)'''
assert callable(func)
def closure(*a, **kw):
return func(*(args + a), **kw)
return closure
def _updatewrapper(wrap, origfn, unboundwrapper):
'''Copy and add some useful attributes to wrapper'''
try:
wrap.__name__ = origfn.__name__
except AttributeError:
pass
wrap.__module__ = getattr(origfn, '__module__')
wrap.__doc__ = getattr(origfn, '__doc__')
wrap.__dict__.update(getattr(origfn, '__dict__', {}))
wrap._origfunc = origfn
wrap._unboundwrapper = unboundwrapper
def wrapcommand(table, command, wrapper, synopsis=None, docstring=None):
'''Wrap the command named `command' in table
Replace command in the command table with wrapper. The wrapped command will
be inserted into the command table specified by the table argument.
The wrapper will be called like
wrapper(orig, *args, **kwargs)
where orig is the original (wrapped) function, and *args, **kwargs
are the arguments passed to it.
Optionally append to the command synopsis and docstring, used for help.
For example, if your extension wraps the ``bookmarks`` command to add the
flags ``--remote`` and ``--all`` you might call this function like so:
synopsis = ' [-a] [--remote]'
docstring = """
The ``remotenames`` extension adds the ``--remote`` and ``--all`` (``-a``)
flags to the bookmarks command. Either flag will show the remote bookmarks
known to the repository; ``--remote`` will also suppress the output of the
local bookmarks.
"""
extensions.wrapcommand(commands.table, 'bookmarks', exbookmarks,
synopsis, docstring)
'''
assert callable(wrapper)
aliases, entry = cmdutil.findcmd(command, table)
for alias, e in table.iteritems():
if e is entry:
key = alias
break
origfn = entry[0]
wrap = functools.partial(util.checksignature(wrapper),
util.checksignature(origfn))
_updatewrapper(wrap, origfn, wrapper)
if docstring is not None:
wrap.__doc__ += docstring
newentry = list(entry)
newentry[0] = wrap
if synopsis is not None:
newentry[2] += synopsis
table[key] = tuple(newentry)
return entry
def wrapfilecache(cls, propname, wrapper):
"""Wraps a filecache property.
These can't be wrapped using the normal wrapfunction.
"""
propname = pycompat.sysstr(propname)
assert callable(wrapper)
for currcls in cls.__mro__:
if propname in currcls.__dict__:
origfn = currcls.__dict__[propname].func
assert callable(origfn)
def wrap(*args, **kwargs):
return wrapper(origfn, *args, **kwargs)
currcls.__dict__[propname].func = wrap
break
if currcls is object:
raise AttributeError(r"type '%s' has no property '%s'" % (
cls, propname))
class wrappedfunction(object):
'''context manager for temporarily wrapping a function'''
def __init__(self, container, funcname, wrapper):
assert callable(wrapper)
self._container = container
self._funcname = funcname
self._wrapper = wrapper
def __enter__(self):
wrapfunction(self._container, self._funcname, self._wrapper)
def __exit__(self, exctype, excvalue, traceback):
unwrapfunction(self._container, self._funcname, self._wrapper)
def wrapfunction(container, funcname, wrapper):
'''Wrap the function named funcname in container
Replace the funcname member in the given container with the specified
wrapper. The container is typically a module, class, or instance.
The wrapper will be called like
wrapper(orig, *args, **kwargs)
where orig is the original (wrapped) function, and *args, **kwargs
are the arguments passed to it.
Wrapping methods of the repository object is not recommended since
it conflicts with extensions that extend the repository by
subclassing. All extensions that need to extend methods of
localrepository should use this subclassing trick: namely,
reposetup() should look like
def reposetup(ui, repo):
class myrepo(repo.__class__):
def whatever(self, *args, **kwargs):
[...extension stuff...]
super(myrepo, self).whatever(*args, **kwargs)
[...extension stuff...]
repo.__class__ = myrepo
In general, combining wrapfunction() with subclassing does not
work. Since you cannot control what other extensions are loaded by
your end users, you should play nicely with others by using the
subclass trick.
'''
assert callable(wrapper)
origfn = getattr(container, funcname)
assert callable(origfn)
if inspect.ismodule(container):
# origfn is not an instance or class method. "partial" can be used.
# "partial" won't insert a frame in traceback.
wrap = functools.partial(wrapper, origfn)
else:
# "partial" cannot be safely used. Emulate its effect by using "bind".
# The downside is one more frame in traceback.
wrap = bind(wrapper, origfn)
_updatewrapper(wrap, origfn, wrapper)
setattr(container, funcname, wrap)
return origfn
def unwrapfunction(container, funcname, wrapper=None):
'''undo wrapfunction
If wrappers is None, undo the last wrap. Otherwise removes the wrapper
from the chain of wrappers.
Return the removed wrapper.
Raise IndexError if wrapper is None and nothing to unwrap; ValueError if
wrapper is not None but is not found in the wrapper chain.
'''
chain = getwrapperchain(container, funcname)
origfn = chain.pop()
if wrapper is None:
wrapper = chain[0]
chain.remove(wrapper)
setattr(container, funcname, origfn)
for w in reversed(chain):
wrapfunction(container, funcname, w)
return wrapper
def getwrapperchain(container, funcname):
'''get a chain of wrappers of a function
Return a list of functions: [newest wrapper, ..., oldest wrapper, origfunc]
The wrapper functions are the ones passed to wrapfunction, whose first
argument is origfunc.
'''
result = []
fn = getattr(container, funcname)
while fn:
assert callable(fn)
result.append(getattr(fn, '_unboundwrapper', fn))
fn = getattr(fn, '_origfunc', None)
return result
def _disabledpaths():
'''find paths of disabled extensions. returns a dict of {name: path}'''
import hgext
extpath = os.path.dirname(
os.path.abspath(pycompat.fsencode(hgext.__file__)))
try: # might not be a filesystem path
files = os.listdir(extpath)
except OSError:
return {}
exts = {}
for e in files:
if e.endswith('.py'):
name = e.rsplit('.', 1)[0]
path = os.path.join(extpath, e)
else:
name = e
path = os.path.join(extpath, e, '__init__.py')
if not os.path.exists(path):
continue
if name in exts or name in _order or name == '__init__':
continue
exts[name] = path
for name, path in _disabledextensions.iteritems():
# If no path was provided for a disabled extension (e.g. "color=!"),
# don't replace the path we already found by the scan above.
if path:
exts[name] = path
return exts
def _moduledoc(file):
'''return the top-level python documentation for the given file
Loosely inspired by pydoc.source_synopsis(), but rewritten to
handle triple quotes and to return the whole text instead of just
the synopsis'''
result = []
line = file.readline()
while line[:1] == '#' or not line.strip():
line = file.readline()
if not line:
break
start = line[:3]
if start == '"""' or start == "'''":
line = line[3:]
while line:
if line.rstrip().endswith(start):
line = line.split(start)[0]
if line:
result.append(line)
break
elif not line:
return None # unmatched delimiter
result.append(line)
line = file.readline()
else:
return None
return ''.join(result)
def _disabledhelp(path):
'''retrieve help synopsis of a disabled extension (without importing)'''
try:
with open(path, 'rb') as src:
doc = _moduledoc(src)
except IOError:
return
if doc: # extracting localized synopsis
return gettext(doc)
else:
return _('(no help text available)')
def disabled():
'''find disabled extensions from hgext. returns a dict of {name: desc}'''
try:
from hgext import __index__
return dict((name, gettext(desc))
for name, desc in __index__.docs.iteritems()
if name not in _order)
except (ImportError, AttributeError):
pass
paths = _disabledpaths()
if not paths:
return {}
exts = {}
for name, path in paths.iteritems():
doc = _disabledhelp(path)
if doc:
exts[name] = doc.splitlines()[0]
return exts
def disabledext(name):
'''find a specific disabled extension from hgext. returns desc'''
try:
from hgext import __index__
if name in _order: # enabled
return
else:
return gettext(__index__.docs.get(name))
except (ImportError, AttributeError):
pass
paths = _disabledpaths()
if name in paths:
return _disabledhelp(paths[name])
def _walkcommand(node):
"""Scan @command() decorators in the tree starting at node"""
todo = collections.deque([node])
while todo:
node = todo.popleft()
if not isinstance(node, ast.FunctionDef):
todo.extend(ast.iter_child_nodes(node))
continue
for d in node.decorator_list:
if not isinstance(d, ast.Call):
continue
if not isinstance(d.func, ast.Name):
continue
if d.func.id != r'command':
continue
yield d
def _disabledcmdtable(path):
"""Construct a dummy command table without loading the extension module
This may raise IOError or SyntaxError.
"""
with open(path, 'rb') as src:
root = ast.parse(src.read(), path)
cmdtable = {}
for node in _walkcommand(root):
if not node.args:
continue
a = node.args[0]
if isinstance(a, ast.Str):
name = pycompat.sysbytes(a.s)
elif pycompat.ispy3 and isinstance(a, ast.Bytes):
name = a.s
else:
continue
cmdtable[name] = (None, [], b'')
return cmdtable
def _finddisabledcmd(ui, cmd, name, path, strict):
try:
cmdtable = _disabledcmdtable(path)
except (IOError, SyntaxError):
return
try:
aliases, entry = cmdutil.findcmd(cmd, cmdtable, strict)
except (error.AmbiguousCommand, error.UnknownCommand):
return
for c in aliases:
if c.startswith(cmd):
cmd = c
break
else:
cmd = aliases[0]
doc = _disabledhelp(path)
return (cmd, name, doc)
def disabledcmd(ui, cmd, strict=False):
'''find cmd from disabled extensions without importing.
returns (cmdname, extname, doc)'''
paths = _disabledpaths()
if not paths:
raise error.UnknownCommand(cmd)
ext = None
# first, search for an extension with the same name as the command
path = paths.pop(cmd, None)
if path:
ext = _finddisabledcmd(ui, cmd, cmd, path, strict=strict)
if not ext:
# otherwise, interrogate each extension until there's a match
for name, path in paths.iteritems():
ext = _finddisabledcmd(ui, cmd, name, path, strict=strict)
if ext:
break
if ext:
return ext
raise error.UnknownCommand(cmd)
def enabled(shortname=True):
'''return a dict of {name: desc} of extensions'''
exts = {}
for ename, ext in extensions():
doc = (gettext(ext.__doc__) or _('(no help text available)'))
if shortname:
ename = ename.split('.')[-1]
exts[ename] = doc.splitlines()[0].strip()
return exts
def notloaded():
'''return short names of extensions that failed to load'''
return [name for name, mod in _extensions.iteritems() if mod is None]
def moduleversion(module):
'''return version information from given module as a string'''
if (util.safehasattr(module, 'getversion')
and callable(module.getversion)):
version = module.getversion()
elif util.safehasattr(module, '__version__'):
version = module.__version__
else:
version = ''
if isinstance(version, (list, tuple)):
version = '.'.join(pycompat.bytestr(o) for o in version)
return version
def ismoduleinternal(module):
exttestedwith = getattr(module, 'testedwith', None)
return exttestedwith == "ships-with-hg-core"