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1942 lines
55 KiB
1942 lines
55 KiB
# util/langhelpers.py
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# Copyright (C) 2005-2022 the SQLAlchemy authors and contributors
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# <see AUTHORS file>
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#
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# This module is part of SQLAlchemy and is released under
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# the MIT License: https://www.opensource.org/licenses/mit-license.php
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"""Routines to help with the creation, loading and introspection of
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modules, classes, hierarchies, attributes, functions, and methods.
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"""
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import collections
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from functools import update_wrapper
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import hashlib
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import inspect
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import itertools
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import operator
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import re
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import sys
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import textwrap
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import types
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import warnings
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from . import _collections
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from . import compat
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from .. import exc
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def md5_hex(x):
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if compat.py3k:
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x = x.encode("utf-8")
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m = hashlib.md5()
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m.update(x)
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return m.hexdigest()
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class safe_reraise(object):
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"""Reraise an exception after invoking some
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handler code.
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Stores the existing exception info before
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invoking so that it is maintained across a potential
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coroutine context switch.
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e.g.::
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try:
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sess.commit()
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except:
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with safe_reraise():
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sess.rollback()
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"""
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__slots__ = ("warn_only", "_exc_info")
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def __init__(self, warn_only=False):
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self.warn_only = warn_only
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def __enter__(self):
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self._exc_info = sys.exc_info()
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def __exit__(self, type_, value, traceback):
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# see #2703 for notes
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if type_ is None:
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exc_type, exc_value, exc_tb = self._exc_info
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self._exc_info = None # remove potential circular references
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if not self.warn_only:
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compat.raise_(
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exc_value,
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with_traceback=exc_tb,
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)
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else:
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if not compat.py3k and self._exc_info and self._exc_info[1]:
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# emulate Py3K's behavior of telling us when an exception
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# occurs in an exception handler.
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warn(
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"An exception has occurred during handling of a "
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"previous exception. The previous exception "
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"is:\n %s %s\n" % (self._exc_info[0], self._exc_info[1])
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)
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self._exc_info = None # remove potential circular references
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compat.raise_(value, with_traceback=traceback)
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def walk_subclasses(cls):
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seen = set()
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stack = [cls]
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while stack:
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cls = stack.pop()
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if cls in seen:
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continue
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else:
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seen.add(cls)
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stack.extend(cls.__subclasses__())
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yield cls
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def string_or_unprintable(element):
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if isinstance(element, compat.string_types):
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return element
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else:
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try:
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return str(element)
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except Exception:
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return "unprintable element %r" % element
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def clsname_as_plain_name(cls):
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return " ".join(
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n.lower() for n in re.findall(r"([A-Z][a-z]+)", cls.__name__)
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)
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def method_is_overridden(instance_or_cls, against_method):
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"""Return True if the two class methods don't match."""
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if not isinstance(instance_or_cls, type):
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current_cls = instance_or_cls.__class__
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else:
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current_cls = instance_or_cls
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method_name = against_method.__name__
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current_method = getattr(current_cls, method_name)
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return current_method != against_method
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def decode_slice(slc):
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"""decode a slice object as sent to __getitem__.
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takes into account the 2.5 __index__() method, basically.
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"""
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ret = []
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for x in slc.start, slc.stop, slc.step:
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if hasattr(x, "__index__"):
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x = x.__index__()
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ret.append(x)
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return tuple(ret)
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def _unique_symbols(used, *bases):
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used = set(used)
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for base in bases:
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pool = itertools.chain(
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(base,),
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compat.itertools_imap(lambda i: base + str(i), range(1000)),
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)
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for sym in pool:
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if sym not in used:
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used.add(sym)
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yield sym
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break
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else:
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raise NameError("exhausted namespace for symbol base %s" % base)
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def map_bits(fn, n):
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"""Call the given function given each nonzero bit from n."""
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while n:
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b = n & (~n + 1)
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yield fn(b)
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n ^= b
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def decorator(target):
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"""A signature-matching decorator factory."""
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def decorate(fn):
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if not inspect.isfunction(fn) and not inspect.ismethod(fn):
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raise Exception("not a decoratable function")
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spec = compat.inspect_getfullargspec(fn)
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env = {}
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spec = _update_argspec_defaults_into_env(spec, env)
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names = tuple(spec[0]) + spec[1:3] + (fn.__name__,)
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targ_name, fn_name = _unique_symbols(names, "target", "fn")
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metadata = dict(target=targ_name, fn=fn_name)
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metadata.update(format_argspec_plus(spec, grouped=False))
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metadata["name"] = fn.__name__
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code = (
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"""\
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def %(name)s(%(args)s):
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return %(target)s(%(fn)s, %(apply_kw)s)
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"""
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% metadata
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)
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env.update({targ_name: target, fn_name: fn, "__name__": fn.__module__})
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decorated = _exec_code_in_env(code, env, fn.__name__)
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decorated.__defaults__ = getattr(fn, "__func__", fn).__defaults__
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decorated.__wrapped__ = fn
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return update_wrapper(decorated, fn)
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return update_wrapper(decorate, target)
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def _update_argspec_defaults_into_env(spec, env):
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"""given a FullArgSpec, convert defaults to be symbol names in an env."""
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if spec.defaults:
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new_defaults = []
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i = 0
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for arg in spec.defaults:
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if type(arg).__module__ not in ("builtins", "__builtin__"):
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name = "x%d" % i
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env[name] = arg
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new_defaults.append(name)
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i += 1
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else:
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new_defaults.append(arg)
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elem = list(spec)
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elem[3] = tuple(new_defaults)
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return compat.FullArgSpec(*elem)
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else:
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return spec
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def _exec_code_in_env(code, env, fn_name):
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exec(code, env)
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return env[fn_name]
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def public_factory(target, location, class_location=None):
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"""Produce a wrapping function for the given cls or classmethod.
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Rationale here is so that the __init__ method of the
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class can serve as documentation for the function.
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"""
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if isinstance(target, type):
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fn = target.__init__
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callable_ = target
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doc = (
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"Construct a new :class:`%s` object. \n\n"
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"This constructor is mirrored as a public API function; "
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"see :func:`sqlalchemy%s` "
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"for a full usage and argument description."
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% (
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class_location if class_location else ".%s" % target.__name__,
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location,
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)
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)
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else:
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fn = callable_ = target
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doc = (
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"This function is mirrored; see :func:`sqlalchemy%s` "
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"for a description of arguments." % location
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)
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location_name = location.split(".")[-1]
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spec = compat.inspect_getfullargspec(fn)
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del spec[0][0]
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metadata = format_argspec_plus(spec, grouped=False)
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metadata["name"] = location_name
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code = (
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"""\
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def %(name)s(%(args)s):
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return cls(%(apply_kw)s)
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"""
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% metadata
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)
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env = {
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"cls": callable_,
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"symbol": symbol,
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"__name__": callable_.__module__,
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}
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exec(code, env)
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decorated = env[location_name]
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if hasattr(fn, "_linked_to"):
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linked_to, linked_to_location = fn._linked_to
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linked_to_doc = linked_to.__doc__
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if class_location is None:
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class_location = "%s.%s" % (target.__module__, target.__name__)
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linked_to_doc = inject_docstring_text(
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linked_to_doc,
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".. container:: inherited_member\n\n "
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"This documentation is inherited from :func:`sqlalchemy%s`; "
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"this constructor, :func:`sqlalchemy%s`, "
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"creates a :class:`sqlalchemy%s` object. See that class for "
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"additional details describing this subclass."
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% (linked_to_location, location, class_location),
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1,
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)
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decorated.__doc__ = linked_to_doc
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else:
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decorated.__doc__ = fn.__doc__
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decorated.__module__ = "sqlalchemy" + location.rsplit(".", 1)[0]
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if decorated.__module__ not in sys.modules:
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raise ImportError(
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"public_factory location %s is not in sys.modules"
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% (decorated.__module__,)
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)
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if compat.py2k or hasattr(fn, "__func__"):
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fn.__func__.__doc__ = doc
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if not hasattr(fn.__func__, "_linked_to"):
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fn.__func__._linked_to = (decorated, location)
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else:
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fn.__doc__ = doc
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if not hasattr(fn, "_linked_to"):
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fn._linked_to = (decorated, location)
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return decorated
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class PluginLoader(object):
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def __init__(self, group, auto_fn=None):
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self.group = group
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self.impls = {}
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self.auto_fn = auto_fn
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def clear(self):
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self.impls.clear()
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def load(self, name):
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if name in self.impls:
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return self.impls[name]()
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if self.auto_fn:
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loader = self.auto_fn(name)
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if loader:
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self.impls[name] = loader
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return loader()
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for impl in compat.importlib_metadata_get(self.group):
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if impl.name == name:
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self.impls[name] = impl.load
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return impl.load()
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raise exc.NoSuchModuleError(
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"Can't load plugin: %s:%s" % (self.group, name)
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)
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def register(self, name, modulepath, objname):
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def load():
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mod = compat.import_(modulepath)
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for token in modulepath.split(".")[1:]:
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mod = getattr(mod, token)
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return getattr(mod, objname)
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self.impls[name] = load
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def _inspect_func_args(fn):
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try:
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co_varkeywords = inspect.CO_VARKEYWORDS
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except AttributeError:
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# https://docs.python.org/3/library/inspect.html
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# The flags are specific to CPython, and may not be defined in other
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# Python implementations. Furthermore, the flags are an implementation
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# detail, and can be removed or deprecated in future Python releases.
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spec = compat.inspect_getfullargspec(fn)
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return spec[0], bool(spec[2])
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else:
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# use fn.__code__ plus flags to reduce method call overhead
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co = fn.__code__
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nargs = co.co_argcount
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return (
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list(co.co_varnames[:nargs]),
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bool(co.co_flags & co_varkeywords),
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)
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def get_cls_kwargs(cls, _set=None):
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r"""Return the full set of inherited kwargs for the given `cls`.
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Probes a class's __init__ method, collecting all named arguments. If the
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__init__ defines a \**kwargs catch-all, then the constructor is presumed
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to pass along unrecognized keywords to its base classes, and the
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collection process is repeated recursively on each of the bases.
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Uses a subset of inspect.getfullargspec() to cut down on method overhead,
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as this is used within the Core typing system to create copies of type
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objects which is a performance-sensitive operation.
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No anonymous tuple arguments please !
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"""
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toplevel = _set is None
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if toplevel:
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_set = set()
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ctr = cls.__dict__.get("__init__", False)
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has_init = (
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ctr
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and isinstance(ctr, types.FunctionType)
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and isinstance(ctr.__code__, types.CodeType)
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)
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if has_init:
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names, has_kw = _inspect_func_args(ctr)
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_set.update(names)
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if not has_kw and not toplevel:
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return None
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if not has_init or has_kw:
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for c in cls.__bases__:
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if get_cls_kwargs(c, _set) is None:
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break
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_set.discard("self")
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return _set
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def get_func_kwargs(func):
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"""Return the set of legal kwargs for the given `func`.
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Uses getargspec so is safe to call for methods, functions,
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etc.
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"""
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return compat.inspect_getfullargspec(func)[0]
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def get_callable_argspec(fn, no_self=False, _is_init=False):
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"""Return the argument signature for any callable.
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All pure-Python callables are accepted, including
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functions, methods, classes, objects with __call__;
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builtins and other edge cases like functools.partial() objects
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raise a TypeError.
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"""
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if inspect.isbuiltin(fn):
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raise TypeError("Can't inspect builtin: %s" % fn)
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elif inspect.isfunction(fn):
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if _is_init and no_self:
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spec = compat.inspect_getfullargspec(fn)
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return compat.FullArgSpec(
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spec.args[1:],
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spec.varargs,
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spec.varkw,
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spec.defaults,
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spec.kwonlyargs,
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spec.kwonlydefaults,
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spec.annotations,
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)
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else:
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return compat.inspect_getfullargspec(fn)
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elif inspect.ismethod(fn):
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if no_self and (_is_init or fn.__self__):
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spec = compat.inspect_getfullargspec(fn.__func__)
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return compat.FullArgSpec(
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spec.args[1:],
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spec.varargs,
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spec.varkw,
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spec.defaults,
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spec.kwonlyargs,
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spec.kwonlydefaults,
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spec.annotations,
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)
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else:
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return compat.inspect_getfullargspec(fn.__func__)
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elif inspect.isclass(fn):
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return get_callable_argspec(
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fn.__init__, no_self=no_self, _is_init=True
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)
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elif hasattr(fn, "__func__"):
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return compat.inspect_getfullargspec(fn.__func__)
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elif hasattr(fn, "__call__"):
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if inspect.ismethod(fn.__call__):
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return get_callable_argspec(fn.__call__, no_self=no_self)
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else:
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raise TypeError("Can't inspect callable: %s" % fn)
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else:
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raise TypeError("Can't inspect callable: %s" % fn)
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|
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def format_argspec_plus(fn, grouped=True):
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"""Returns a dictionary of formatted, introspected function arguments.
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A enhanced variant of inspect.formatargspec to support code generation.
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fn
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An inspectable callable or tuple of inspect getargspec() results.
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grouped
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Defaults to True; include (parens, around, argument) lists
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Returns:
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args
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Full inspect.formatargspec for fn
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self_arg
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The name of the first positional argument, varargs[0], or None
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if the function defines no positional arguments.
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apply_pos
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args, re-written in calling rather than receiving syntax. Arguments are
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passed positionally.
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apply_kw
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Like apply_pos, except keyword-ish args are passed as keywords.
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apply_pos_proxied
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Like apply_pos but omits the self/cls argument
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Example::
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>>> format_argspec_plus(lambda self, a, b, c=3, **d: 123)
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{'args': '(self, a, b, c=3, **d)',
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'self_arg': 'self',
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'apply_kw': '(self, a, b, c=c, **d)',
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'apply_pos': '(self, a, b, c, **d)'}
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"""
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if compat.callable(fn):
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spec = compat.inspect_getfullargspec(fn)
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else:
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spec = fn
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args = compat.inspect_formatargspec(*spec)
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apply_pos = compat.inspect_formatargspec(
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spec[0], spec[1], spec[2], None, spec[4]
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)
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if spec[0]:
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self_arg = spec[0][0]
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apply_pos_proxied = compat.inspect_formatargspec(
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spec[0][1:], spec[1], spec[2], None, spec[4]
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)
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elif spec[1]:
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# I'm not sure what this is
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self_arg = "%s[0]" % spec[1]
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apply_pos_proxied = apply_pos
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else:
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self_arg = None
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apply_pos_proxied = apply_pos
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num_defaults = 0
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if spec[3]:
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num_defaults += len(spec[3])
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if spec[4]:
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num_defaults += len(spec[4])
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name_args = spec[0] + spec[4]
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if num_defaults:
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defaulted_vals = name_args[0 - num_defaults :]
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else:
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defaulted_vals = ()
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apply_kw = compat.inspect_formatargspec(
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name_args,
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spec[1],
|
|
spec[2],
|
|
defaulted_vals,
|
|
formatvalue=lambda x: "=" + x,
|
|
)
|
|
|
|
if spec[0]:
|
|
apply_kw_proxied = compat.inspect_formatargspec(
|
|
name_args[1:],
|
|
spec[1],
|
|
spec[2],
|
|
defaulted_vals,
|
|
formatvalue=lambda x: "=" + x,
|
|
)
|
|
else:
|
|
apply_kw_proxied = apply_kw
|
|
|
|
if grouped:
|
|
return dict(
|
|
args=args,
|
|
self_arg=self_arg,
|
|
apply_pos=apply_pos,
|
|
apply_kw=apply_kw,
|
|
apply_pos_proxied=apply_pos_proxied,
|
|
apply_kw_proxied=apply_kw_proxied,
|
|
)
|
|
else:
|
|
return dict(
|
|
args=args[1:-1],
|
|
self_arg=self_arg,
|
|
apply_pos=apply_pos[1:-1],
|
|
apply_kw=apply_kw[1:-1],
|
|
apply_pos_proxied=apply_pos_proxied[1:-1],
|
|
apply_kw_proxied=apply_kw_proxied[1:-1],
|
|
)
|
|
|
|
|
|
def format_argspec_init(method, grouped=True):
|
|
"""format_argspec_plus with considerations for typical __init__ methods
|
|
|
|
Wraps format_argspec_plus with error handling strategies for typical
|
|
__init__ cases::
|
|
|
|
object.__init__ -> (self)
|
|
other unreflectable (usually C) -> (self, *args, **kwargs)
|
|
|
|
"""
|
|
if method is object.__init__:
|
|
args = "(self)" if grouped else "self"
|
|
proxied = "()" if grouped else ""
|
|
else:
|
|
try:
|
|
return format_argspec_plus(method, grouped=grouped)
|
|
except TypeError:
|
|
args = (
|
|
"(self, *args, **kwargs)"
|
|
if grouped
|
|
else "self, *args, **kwargs"
|
|
)
|
|
proxied = "(*args, **kwargs)" if grouped else "*args, **kwargs"
|
|
return dict(
|
|
self_arg="self",
|
|
args=args,
|
|
apply_pos=args,
|
|
apply_kw=args,
|
|
apply_pos_proxied=proxied,
|
|
apply_kw_proxied=proxied,
|
|
)
|
|
|
|
|
|
def create_proxy_methods(
|
|
target_cls,
|
|
target_cls_sphinx_name,
|
|
proxy_cls_sphinx_name,
|
|
classmethods=(),
|
|
methods=(),
|
|
attributes=(),
|
|
):
|
|
"""A class decorator that will copy attributes to a proxy class.
|
|
|
|
The class to be instrumented must define a single accessor "_proxied".
|
|
|
|
"""
|
|
|
|
def decorate(cls):
|
|
def instrument(name, clslevel=False):
|
|
fn = getattr(target_cls, name)
|
|
spec = compat.inspect_getfullargspec(fn)
|
|
env = {"__name__": fn.__module__}
|
|
|
|
spec = _update_argspec_defaults_into_env(spec, env)
|
|
caller_argspec = format_argspec_plus(spec, grouped=False)
|
|
|
|
metadata = {
|
|
"name": fn.__name__,
|
|
"apply_pos_proxied": caller_argspec["apply_pos_proxied"],
|
|
"apply_kw_proxied": caller_argspec["apply_kw_proxied"],
|
|
"args": caller_argspec["args"],
|
|
"self_arg": caller_argspec["self_arg"],
|
|
}
|
|
|
|
if clslevel:
|
|
code = (
|
|
"def %(name)s(%(args)s):\n"
|
|
" return target_cls.%(name)s(%(apply_kw_proxied)s)"
|
|
% metadata
|
|
)
|
|
env["target_cls"] = target_cls
|
|
else:
|
|
code = (
|
|
"def %(name)s(%(args)s):\n"
|
|
" return %(self_arg)s._proxied.%(name)s(%(apply_kw_proxied)s)" # noqa: E501
|
|
% metadata
|
|
)
|
|
|
|
proxy_fn = _exec_code_in_env(code, env, fn.__name__)
|
|
proxy_fn.__defaults__ = getattr(fn, "__func__", fn).__defaults__
|
|
proxy_fn.__doc__ = inject_docstring_text(
|
|
fn.__doc__,
|
|
".. container:: class_bases\n\n "
|
|
"Proxied for the %s class on behalf of the %s class."
|
|
% (target_cls_sphinx_name, proxy_cls_sphinx_name),
|
|
1,
|
|
)
|
|
|
|
if clslevel:
|
|
proxy_fn = classmethod(proxy_fn)
|
|
|
|
return proxy_fn
|
|
|
|
def makeprop(name):
|
|
attr = target_cls.__dict__.get(name, None)
|
|
|
|
if attr is not None:
|
|
doc = inject_docstring_text(
|
|
attr.__doc__,
|
|
".. container:: class_bases\n\n "
|
|
"Proxied for the %s class on behalf of the %s class."
|
|
% (
|
|
target_cls_sphinx_name,
|
|
proxy_cls_sphinx_name,
|
|
),
|
|
1,
|
|
)
|
|
else:
|
|
doc = None
|
|
|
|
code = (
|
|
"def set_(self, attr):\n"
|
|
" self._proxied.%(name)s = attr\n"
|
|
"def get(self):\n"
|
|
" return self._proxied.%(name)s\n"
|
|
"get.__doc__ = doc\n"
|
|
"getset = property(get, set_)"
|
|
) % {"name": name}
|
|
|
|
getset = _exec_code_in_env(code, {"doc": doc}, "getset")
|
|
|
|
return getset
|
|
|
|
for meth in methods:
|
|
if hasattr(cls, meth):
|
|
raise TypeError(
|
|
"class %s already has a method %s" % (cls, meth)
|
|
)
|
|
setattr(cls, meth, instrument(meth))
|
|
|
|
for prop in attributes:
|
|
if hasattr(cls, prop):
|
|
raise TypeError(
|
|
"class %s already has a method %s" % (cls, prop)
|
|
)
|
|
setattr(cls, prop, makeprop(prop))
|
|
|
|
for prop in classmethods:
|
|
if hasattr(cls, prop):
|
|
raise TypeError(
|
|
"class %s already has a method %s" % (cls, prop)
|
|
)
|
|
setattr(cls, prop, instrument(prop, clslevel=True))
|
|
|
|
return cls
|
|
|
|
return decorate
|
|
|
|
|
|
def getargspec_init(method):
|
|
"""inspect.getargspec with considerations for typical __init__ methods
|
|
|
|
Wraps inspect.getargspec with error handling for typical __init__ cases::
|
|
|
|
object.__init__ -> (self)
|
|
other unreflectable (usually C) -> (self, *args, **kwargs)
|
|
|
|
"""
|
|
try:
|
|
return compat.inspect_getfullargspec(method)
|
|
except TypeError:
|
|
if method is object.__init__:
|
|
return (["self"], None, None, None)
|
|
else:
|
|
return (["self"], "args", "kwargs", None)
|
|
|
|
|
|
def unbound_method_to_callable(func_or_cls):
|
|
"""Adjust the incoming callable such that a 'self' argument is not
|
|
required.
|
|
|
|
"""
|
|
|
|
if isinstance(func_or_cls, types.MethodType) and not func_or_cls.__self__:
|
|
return func_or_cls.__func__
|
|
else:
|
|
return func_or_cls
|
|
|
|
|
|
def generic_repr(obj, additional_kw=(), to_inspect=None, omit_kwarg=()):
|
|
"""Produce a __repr__() based on direct association of the __init__()
|
|
specification vs. same-named attributes present.
|
|
|
|
"""
|
|
if to_inspect is None:
|
|
to_inspect = [obj]
|
|
else:
|
|
to_inspect = _collections.to_list(to_inspect)
|
|
|
|
missing = object()
|
|
|
|
pos_args = []
|
|
kw_args = _collections.OrderedDict()
|
|
vargs = None
|
|
for i, insp in enumerate(to_inspect):
|
|
try:
|
|
spec = compat.inspect_getfullargspec(insp.__init__)
|
|
except TypeError:
|
|
continue
|
|
else:
|
|
default_len = spec.defaults and len(spec.defaults) or 0
|
|
if i == 0:
|
|
if spec.varargs:
|
|
vargs = spec.varargs
|
|
if default_len:
|
|
pos_args.extend(spec.args[1:-default_len])
|
|
else:
|
|
pos_args.extend(spec.args[1:])
|
|
else:
|
|
kw_args.update(
|
|
[(arg, missing) for arg in spec.args[1:-default_len]]
|
|
)
|
|
|
|
if default_len:
|
|
kw_args.update(
|
|
[
|
|
(arg, default)
|
|
for arg, default in zip(
|
|
spec.args[-default_len:], spec.defaults
|
|
)
|
|
]
|
|
)
|
|
output = []
|
|
|
|
output.extend(repr(getattr(obj, arg, None)) for arg in pos_args)
|
|
|
|
if vargs is not None and hasattr(obj, vargs):
|
|
output.extend([repr(val) for val in getattr(obj, vargs)])
|
|
|
|
for arg, defval in kw_args.items():
|
|
if arg in omit_kwarg:
|
|
continue
|
|
try:
|
|
val = getattr(obj, arg, missing)
|
|
if val is not missing and val != defval:
|
|
output.append("%s=%r" % (arg, val))
|
|
except Exception:
|
|
pass
|
|
|
|
if additional_kw:
|
|
for arg, defval in additional_kw:
|
|
try:
|
|
val = getattr(obj, arg, missing)
|
|
if val is not missing and val != defval:
|
|
output.append("%s=%r" % (arg, val))
|
|
except Exception:
|
|
pass
|
|
|
|
return "%s(%s)" % (obj.__class__.__name__, ", ".join(output))
|
|
|
|
|
|
class portable_instancemethod(object):
|
|
"""Turn an instancemethod into a (parent, name) pair
|
|
to produce a serializable callable.
|
|
|
|
"""
|
|
|
|
__slots__ = "target", "name", "kwargs", "__weakref__"
|
|
|
|
def __getstate__(self):
|
|
return {
|
|
"target": self.target,
|
|
"name": self.name,
|
|
"kwargs": self.kwargs,
|
|
}
|
|
|
|
def __setstate__(self, state):
|
|
self.target = state["target"]
|
|
self.name = state["name"]
|
|
self.kwargs = state.get("kwargs", ())
|
|
|
|
def __init__(self, meth, kwargs=()):
|
|
self.target = meth.__self__
|
|
self.name = meth.__name__
|
|
self.kwargs = kwargs
|
|
|
|
def __call__(self, *arg, **kw):
|
|
kw.update(self.kwargs)
|
|
return getattr(self.target, self.name)(*arg, **kw)
|
|
|
|
|
|
def class_hierarchy(cls):
|
|
"""Return an unordered sequence of all classes related to cls.
|
|
|
|
Traverses diamond hierarchies.
|
|
|
|
Fibs slightly: subclasses of builtin types are not returned. Thus
|
|
class_hierarchy(class A(object)) returns (A, object), not A plus every
|
|
class systemwide that derives from object.
|
|
|
|
Old-style classes are discarded and hierarchies rooted on them
|
|
will not be descended.
|
|
|
|
"""
|
|
if compat.py2k:
|
|
if isinstance(cls, types.ClassType):
|
|
return list()
|
|
|
|
hier = {cls}
|
|
process = list(cls.__mro__)
|
|
while process:
|
|
c = process.pop()
|
|
if compat.py2k:
|
|
if isinstance(c, types.ClassType):
|
|
continue
|
|
bases = (
|
|
_
|
|
for _ in c.__bases__
|
|
if _ not in hier and not isinstance(_, types.ClassType)
|
|
)
|
|
else:
|
|
bases = (_ for _ in c.__bases__ if _ not in hier)
|
|
|
|
for b in bases:
|
|
process.append(b)
|
|
hier.add(b)
|
|
|
|
if compat.py3k:
|
|
if c.__module__ == "builtins" or not hasattr(c, "__subclasses__"):
|
|
continue
|
|
else:
|
|
if c.__module__ == "__builtin__" or not hasattr(
|
|
c, "__subclasses__"
|
|
):
|
|
continue
|
|
|
|
for s in [_ for _ in c.__subclasses__() if _ not in hier]:
|
|
process.append(s)
|
|
hier.add(s)
|
|
return list(hier)
|
|
|
|
|
|
def iterate_attributes(cls):
|
|
"""iterate all the keys and attributes associated
|
|
with a class, without using getattr().
|
|
|
|
Does not use getattr() so that class-sensitive
|
|
descriptors (i.e. property.__get__()) are not called.
|
|
|
|
"""
|
|
keys = dir(cls)
|
|
for key in keys:
|
|
for c in cls.__mro__:
|
|
if key in c.__dict__:
|
|
yield (key, c.__dict__[key])
|
|
break
|
|
|
|
|
|
def monkeypatch_proxied_specials(
|
|
into_cls,
|
|
from_cls,
|
|
skip=None,
|
|
only=None,
|
|
name="self.proxy",
|
|
from_instance=None,
|
|
):
|
|
"""Automates delegation of __specials__ for a proxying type."""
|
|
|
|
if only:
|
|
dunders = only
|
|
else:
|
|
if skip is None:
|
|
skip = (
|
|
"__slots__",
|
|
"__del__",
|
|
"__getattribute__",
|
|
"__metaclass__",
|
|
"__getstate__",
|
|
"__setstate__",
|
|
)
|
|
dunders = [
|
|
m
|
|
for m in dir(from_cls)
|
|
if (
|
|
m.startswith("__")
|
|
and m.endswith("__")
|
|
and not hasattr(into_cls, m)
|
|
and m not in skip
|
|
)
|
|
]
|
|
|
|
for method in dunders:
|
|
try:
|
|
fn = getattr(from_cls, method)
|
|
if not hasattr(fn, "__call__"):
|
|
continue
|
|
fn = getattr(fn, "__func__", fn)
|
|
except AttributeError:
|
|
continue
|
|
try:
|
|
spec = compat.inspect_getfullargspec(fn)
|
|
fn_args = compat.inspect_formatargspec(spec[0])
|
|
d_args = compat.inspect_formatargspec(spec[0][1:])
|
|
except TypeError:
|
|
fn_args = "(self, *args, **kw)"
|
|
d_args = "(*args, **kw)"
|
|
|
|
py = (
|
|
"def %(method)s%(fn_args)s: "
|
|
"return %(name)s.%(method)s%(d_args)s" % locals()
|
|
)
|
|
|
|
env = from_instance is not None and {name: from_instance} or {}
|
|
compat.exec_(py, env)
|
|
try:
|
|
env[method].__defaults__ = fn.__defaults__
|
|
except AttributeError:
|
|
pass
|
|
setattr(into_cls, method, env[method])
|
|
|
|
|
|
def methods_equivalent(meth1, meth2):
|
|
"""Return True if the two methods are the same implementation."""
|
|
|
|
return getattr(meth1, "__func__", meth1) is getattr(
|
|
meth2, "__func__", meth2
|
|
)
|
|
|
|
|
|
def as_interface(obj, cls=None, methods=None, required=None):
|
|
"""Ensure basic interface compliance for an instance or dict of callables.
|
|
|
|
Checks that ``obj`` implements public methods of ``cls`` or has members
|
|
listed in ``methods``. If ``required`` is not supplied, implementing at
|
|
least one interface method is sufficient. Methods present on ``obj`` that
|
|
are not in the interface are ignored.
|
|
|
|
If ``obj`` is a dict and ``dict`` does not meet the interface
|
|
requirements, the keys of the dictionary are inspected. Keys present in
|
|
``obj`` that are not in the interface will raise TypeErrors.
|
|
|
|
Raises TypeError if ``obj`` does not meet the interface criteria.
|
|
|
|
In all passing cases, an object with callable members is returned. In the
|
|
simple case, ``obj`` is returned as-is; if dict processing kicks in then
|
|
an anonymous class is returned.
|
|
|
|
obj
|
|
A type, instance, or dictionary of callables.
|
|
cls
|
|
Optional, a type. All public methods of cls are considered the
|
|
interface. An ``obj`` instance of cls will always pass, ignoring
|
|
``required``..
|
|
methods
|
|
Optional, a sequence of method names to consider as the interface.
|
|
required
|
|
Optional, a sequence of mandatory implementations. If omitted, an
|
|
``obj`` that provides at least one interface method is considered
|
|
sufficient. As a convenience, required may be a type, in which case
|
|
all public methods of the type are required.
|
|
|
|
"""
|
|
if not cls and not methods:
|
|
raise TypeError("a class or collection of method names are required")
|
|
|
|
if isinstance(cls, type) and isinstance(obj, cls):
|
|
return obj
|
|
|
|
interface = set(methods or [m for m in dir(cls) if not m.startswith("_")])
|
|
implemented = set(dir(obj))
|
|
|
|
complies = operator.ge
|
|
if isinstance(required, type):
|
|
required = interface
|
|
elif not required:
|
|
required = set()
|
|
complies = operator.gt
|
|
else:
|
|
required = set(required)
|
|
|
|
if complies(implemented.intersection(interface), required):
|
|
return obj
|
|
|
|
# No dict duck typing here.
|
|
if not isinstance(obj, dict):
|
|
qualifier = complies is operator.gt and "any of" or "all of"
|
|
raise TypeError(
|
|
"%r does not implement %s: %s"
|
|
% (obj, qualifier, ", ".join(interface))
|
|
)
|
|
|
|
class AnonymousInterface(object):
|
|
"""A callable-holding shell."""
|
|
|
|
if cls:
|
|
AnonymousInterface.__name__ = "Anonymous" + cls.__name__
|
|
found = set()
|
|
|
|
for method, impl in dictlike_iteritems(obj):
|
|
if method not in interface:
|
|
raise TypeError("%r: unknown in this interface" % method)
|
|
if not compat.callable(impl):
|
|
raise TypeError("%r=%r is not callable" % (method, impl))
|
|
setattr(AnonymousInterface, method, staticmethod(impl))
|
|
found.add(method)
|
|
|
|
if complies(found, required):
|
|
return AnonymousInterface
|
|
|
|
raise TypeError(
|
|
"dictionary does not contain required keys %s"
|
|
% ", ".join(required - found)
|
|
)
|
|
|
|
|
|
class memoized_property(object):
|
|
"""A read-only @property that is only evaluated once."""
|
|
|
|
def __init__(self, fget, doc=None):
|
|
self.fget = fget
|
|
self.__doc__ = doc or fget.__doc__
|
|
self.__name__ = fget.__name__
|
|
|
|
def __get__(self, obj, cls):
|
|
if obj is None:
|
|
return self
|
|
obj.__dict__[self.__name__] = result = self.fget(obj)
|
|
return result
|
|
|
|
def _reset(self, obj):
|
|
memoized_property.reset(obj, self.__name__)
|
|
|
|
@classmethod
|
|
def reset(cls, obj, name):
|
|
obj.__dict__.pop(name, None)
|
|
|
|
|
|
def memoized_instancemethod(fn):
|
|
"""Decorate a method memoize its return value.
|
|
|
|
Best applied to no-arg methods: memoization is not sensitive to
|
|
argument values, and will always return the same value even when
|
|
called with different arguments.
|
|
|
|
"""
|
|
|
|
def oneshot(self, *args, **kw):
|
|
result = fn(self, *args, **kw)
|
|
|
|
def memo(*a, **kw):
|
|
return result
|
|
|
|
memo.__name__ = fn.__name__
|
|
memo.__doc__ = fn.__doc__
|
|
self.__dict__[fn.__name__] = memo
|
|
return result
|
|
|
|
return update_wrapper(oneshot, fn)
|
|
|
|
|
|
class HasMemoized(object):
|
|
"""A class that maintains the names of memoized elements in a
|
|
collection for easy cache clearing, generative, etc.
|
|
|
|
"""
|
|
|
|
__slots__ = ()
|
|
|
|
_memoized_keys = frozenset()
|
|
|
|
def _reset_memoizations(self):
|
|
for elem in self._memoized_keys:
|
|
self.__dict__.pop(elem, None)
|
|
|
|
def _assert_no_memoizations(self):
|
|
for elem in self._memoized_keys:
|
|
assert elem not in self.__dict__
|
|
|
|
def _set_memoized_attribute(self, key, value):
|
|
self.__dict__[key] = value
|
|
self._memoized_keys |= {key}
|
|
|
|
class memoized_attribute(object):
|
|
"""A read-only @property that is only evaluated once."""
|
|
|
|
def __init__(self, fget, doc=None):
|
|
self.fget = fget
|
|
self.__doc__ = doc or fget.__doc__
|
|
self.__name__ = fget.__name__
|
|
|
|
def __get__(self, obj, cls):
|
|
if obj is None:
|
|
return self
|
|
obj.__dict__[self.__name__] = result = self.fget(obj)
|
|
obj._memoized_keys |= {self.__name__}
|
|
return result
|
|
|
|
@classmethod
|
|
def memoized_instancemethod(cls, fn):
|
|
"""Decorate a method memoize its return value."""
|
|
|
|
def oneshot(self, *args, **kw):
|
|
result = fn(self, *args, **kw)
|
|
|
|
def memo(*a, **kw):
|
|
return result
|
|
|
|
memo.__name__ = fn.__name__
|
|
memo.__doc__ = fn.__doc__
|
|
self.__dict__[fn.__name__] = memo
|
|
self._memoized_keys |= {fn.__name__}
|
|
return result
|
|
|
|
return update_wrapper(oneshot, fn)
|
|
|
|
|
|
class MemoizedSlots(object):
|
|
"""Apply memoized items to an object using a __getattr__ scheme.
|
|
|
|
This allows the functionality of memoized_property and
|
|
memoized_instancemethod to be available to a class using __slots__.
|
|
|
|
"""
|
|
|
|
__slots__ = ()
|
|
|
|
def _fallback_getattr(self, key):
|
|
raise AttributeError(key)
|
|
|
|
def __getattr__(self, key):
|
|
if key.startswith("_memoized"):
|
|
raise AttributeError(key)
|
|
elif hasattr(self, "_memoized_attr_%s" % key):
|
|
value = getattr(self, "_memoized_attr_%s" % key)()
|
|
setattr(self, key, value)
|
|
return value
|
|
elif hasattr(self, "_memoized_method_%s" % key):
|
|
fn = getattr(self, "_memoized_method_%s" % key)
|
|
|
|
def oneshot(*args, **kw):
|
|
result = fn(*args, **kw)
|
|
|
|
def memo(*a, **kw):
|
|
return result
|
|
|
|
memo.__name__ = fn.__name__
|
|
memo.__doc__ = fn.__doc__
|
|
setattr(self, key, memo)
|
|
return result
|
|
|
|
oneshot.__doc__ = fn.__doc__
|
|
return oneshot
|
|
else:
|
|
return self._fallback_getattr(key)
|
|
|
|
|
|
# from paste.deploy.converters
|
|
def asbool(obj):
|
|
if isinstance(obj, compat.string_types):
|
|
obj = obj.strip().lower()
|
|
if obj in ["true", "yes", "on", "y", "t", "1"]:
|
|
return True
|
|
elif obj in ["false", "no", "off", "n", "f", "0"]:
|
|
return False
|
|
else:
|
|
raise ValueError("String is not true/false: %r" % obj)
|
|
return bool(obj)
|
|
|
|
|
|
def bool_or_str(*text):
|
|
"""Return a callable that will evaluate a string as
|
|
boolean, or one of a set of "alternate" string values.
|
|
|
|
"""
|
|
|
|
def bool_or_value(obj):
|
|
if obj in text:
|
|
return obj
|
|
else:
|
|
return asbool(obj)
|
|
|
|
return bool_or_value
|
|
|
|
|
|
def asint(value):
|
|
"""Coerce to integer."""
|
|
|
|
if value is None:
|
|
return value
|
|
return int(value)
|
|
|
|
|
|
def coerce_kw_type(kw, key, type_, flexi_bool=True, dest=None):
|
|
r"""If 'key' is present in dict 'kw', coerce its value to type 'type\_' if
|
|
necessary. If 'flexi_bool' is True, the string '0' is considered false
|
|
when coercing to boolean.
|
|
"""
|
|
|
|
if dest is None:
|
|
dest = kw
|
|
|
|
if (
|
|
key in kw
|
|
and (not isinstance(type_, type) or not isinstance(kw[key], type_))
|
|
and kw[key] is not None
|
|
):
|
|
if type_ is bool and flexi_bool:
|
|
dest[key] = asbool(kw[key])
|
|
else:
|
|
dest[key] = type_(kw[key])
|
|
|
|
|
|
def constructor_key(obj, cls):
|
|
"""Produce a tuple structure that is cacheable using the __dict__ of
|
|
obj to retrieve values
|
|
|
|
"""
|
|
names = get_cls_kwargs(cls)
|
|
return (cls,) + tuple(
|
|
(k, obj.__dict__[k]) for k in names if k in obj.__dict__
|
|
)
|
|
|
|
|
|
def constructor_copy(obj, cls, *args, **kw):
|
|
"""Instantiate cls using the __dict__ of obj as constructor arguments.
|
|
|
|
Uses inspect to match the named arguments of ``cls``.
|
|
|
|
"""
|
|
|
|
names = get_cls_kwargs(cls)
|
|
kw.update(
|
|
(k, obj.__dict__[k]) for k in names.difference(kw) if k in obj.__dict__
|
|
)
|
|
return cls(*args, **kw)
|
|
|
|
|
|
def counter():
|
|
"""Return a threadsafe counter function."""
|
|
|
|
lock = compat.threading.Lock()
|
|
counter = itertools.count(1)
|
|
|
|
# avoid the 2to3 "next" transformation...
|
|
def _next():
|
|
with lock:
|
|
return next(counter)
|
|
|
|
return _next
|
|
|
|
|
|
def duck_type_collection(specimen, default=None):
|
|
"""Given an instance or class, guess if it is or is acting as one of
|
|
the basic collection types: list, set and dict. If the __emulates__
|
|
property is present, return that preferentially.
|
|
"""
|
|
|
|
if hasattr(specimen, "__emulates__"):
|
|
# canonicalize set vs sets.Set to a standard: the builtin set
|
|
if specimen.__emulates__ is not None and issubclass(
|
|
specimen.__emulates__, set
|
|
):
|
|
return set
|
|
else:
|
|
return specimen.__emulates__
|
|
|
|
isa = isinstance(specimen, type) and issubclass or isinstance
|
|
if isa(specimen, list):
|
|
return list
|
|
elif isa(specimen, set):
|
|
return set
|
|
elif isa(specimen, dict):
|
|
return dict
|
|
|
|
if hasattr(specimen, "append"):
|
|
return list
|
|
elif hasattr(specimen, "add"):
|
|
return set
|
|
elif hasattr(specimen, "set"):
|
|
return dict
|
|
else:
|
|
return default
|
|
|
|
|
|
def assert_arg_type(arg, argtype, name):
|
|
if isinstance(arg, argtype):
|
|
return arg
|
|
else:
|
|
if isinstance(argtype, tuple):
|
|
raise exc.ArgumentError(
|
|
"Argument '%s' is expected to be one of type %s, got '%s'"
|
|
% (name, " or ".join("'%s'" % a for a in argtype), type(arg))
|
|
)
|
|
else:
|
|
raise exc.ArgumentError(
|
|
"Argument '%s' is expected to be of type '%s', got '%s'"
|
|
% (name, argtype, type(arg))
|
|
)
|
|
|
|
|
|
def dictlike_iteritems(dictlike):
|
|
"""Return a (key, value) iterator for almost any dict-like object."""
|
|
|
|
if compat.py3k:
|
|
if hasattr(dictlike, "items"):
|
|
return list(dictlike.items())
|
|
else:
|
|
if hasattr(dictlike, "iteritems"):
|
|
return dictlike.iteritems()
|
|
elif hasattr(dictlike, "items"):
|
|
return iter(dictlike.items())
|
|
|
|
getter = getattr(dictlike, "__getitem__", getattr(dictlike, "get", None))
|
|
if getter is None:
|
|
raise TypeError("Object '%r' is not dict-like" % dictlike)
|
|
|
|
if hasattr(dictlike, "iterkeys"):
|
|
|
|
def iterator():
|
|
for key in dictlike.iterkeys():
|
|
yield key, getter(key)
|
|
|
|
return iterator()
|
|
elif hasattr(dictlike, "keys"):
|
|
return iter((key, getter(key)) for key in dictlike.keys())
|
|
else:
|
|
raise TypeError("Object '%r' is not dict-like" % dictlike)
|
|
|
|
|
|
class classproperty(property):
|
|
"""A decorator that behaves like @property except that operates
|
|
on classes rather than instances.
|
|
|
|
The decorator is currently special when using the declarative
|
|
module, but note that the
|
|
:class:`~.sqlalchemy.ext.declarative.declared_attr`
|
|
decorator should be used for this purpose with declarative.
|
|
|
|
"""
|
|
|
|
def __init__(self, fget, *arg, **kw):
|
|
super(classproperty, self).__init__(fget, *arg, **kw)
|
|
self.__doc__ = fget.__doc__
|
|
|
|
def __get__(desc, self, cls):
|
|
return desc.fget(cls)
|
|
|
|
|
|
class hybridproperty(object):
|
|
def __init__(self, func):
|
|
self.func = func
|
|
self.clslevel = func
|
|
|
|
def __get__(self, instance, owner):
|
|
if instance is None:
|
|
clsval = self.clslevel(owner)
|
|
return clsval
|
|
else:
|
|
return self.func(instance)
|
|
|
|
def classlevel(self, func):
|
|
self.clslevel = func
|
|
return self
|
|
|
|
|
|
class hybridmethod(object):
|
|
"""Decorate a function as cls- or instance- level."""
|
|
|
|
def __init__(self, func):
|
|
self.func = self.__func__ = func
|
|
self.clslevel = func
|
|
|
|
def __get__(self, instance, owner):
|
|
if instance is None:
|
|
return self.clslevel.__get__(owner, owner.__class__)
|
|
else:
|
|
return self.func.__get__(instance, owner)
|
|
|
|
def classlevel(self, func):
|
|
self.clslevel = func
|
|
return self
|
|
|
|
|
|
class _symbol(int):
|
|
def __new__(self, name, doc=None, canonical=None):
|
|
"""Construct a new named symbol."""
|
|
assert isinstance(name, compat.string_types)
|
|
if canonical is None:
|
|
canonical = hash(name)
|
|
v = int.__new__(_symbol, canonical)
|
|
v.name = name
|
|
if doc:
|
|
v.__doc__ = doc
|
|
return v
|
|
|
|
def __reduce__(self):
|
|
return symbol, (self.name, "x", int(self))
|
|
|
|
def __str__(self):
|
|
return repr(self)
|
|
|
|
def __repr__(self):
|
|
return "symbol(%r)" % self.name
|
|
|
|
|
|
_symbol.__name__ = "symbol"
|
|
|
|
|
|
class symbol(object):
|
|
"""A constant symbol.
|
|
|
|
>>> symbol('foo') is symbol('foo')
|
|
True
|
|
>>> symbol('foo')
|
|
<symbol 'foo>
|
|
|
|
A slight refinement of the MAGICCOOKIE=object() pattern. The primary
|
|
advantage of symbol() is its repr(). They are also singletons.
|
|
|
|
Repeated calls of symbol('name') will all return the same instance.
|
|
|
|
The optional ``doc`` argument assigns to ``__doc__``. This
|
|
is strictly so that Sphinx autoattr picks up the docstring we want
|
|
(it doesn't appear to pick up the in-module docstring if the datamember
|
|
is in a different module - autoattribute also blows up completely).
|
|
If Sphinx fixes/improves this then we would no longer need
|
|
``doc`` here.
|
|
|
|
"""
|
|
|
|
symbols = {}
|
|
_lock = compat.threading.Lock()
|
|
|
|
def __new__(cls, name, doc=None, canonical=None):
|
|
with cls._lock:
|
|
sym = cls.symbols.get(name)
|
|
if sym is None:
|
|
cls.symbols[name] = sym = _symbol(name, doc, canonical)
|
|
return sym
|
|
|
|
@classmethod
|
|
def parse_user_argument(
|
|
cls, arg, choices, name, resolve_symbol_names=False
|
|
):
|
|
"""Given a user parameter, parse the parameter into a chosen symbol.
|
|
|
|
The user argument can be a string name that matches the name of a
|
|
symbol, or the symbol object itself, or any number of alternate choices
|
|
such as True/False/ None etc.
|
|
|
|
:param arg: the user argument.
|
|
:param choices: dictionary of symbol object to list of possible
|
|
entries.
|
|
:param name: name of the argument. Used in an :class:`.ArgumentError`
|
|
that is raised if the parameter doesn't match any available argument.
|
|
:param resolve_symbol_names: include the name of each symbol as a valid
|
|
entry.
|
|
|
|
"""
|
|
# note using hash lookup is tricky here because symbol's `__hash__`
|
|
# is its int value which we don't want included in the lookup
|
|
# explicitly, so we iterate and compare each.
|
|
for sym, choice in choices.items():
|
|
if arg is sym:
|
|
return sym
|
|
elif resolve_symbol_names and arg == sym.name:
|
|
return sym
|
|
elif arg in choice:
|
|
return sym
|
|
|
|
if arg is None:
|
|
return None
|
|
|
|
raise exc.ArgumentError("Invalid value for '%s': %r" % (name, arg))
|
|
|
|
|
|
_creation_order = 1
|
|
|
|
|
|
def set_creation_order(instance):
|
|
"""Assign a '_creation_order' sequence to the given instance.
|
|
|
|
This allows multiple instances to be sorted in order of creation
|
|
(typically within a single thread; the counter is not particularly
|
|
threadsafe).
|
|
|
|
"""
|
|
global _creation_order
|
|
instance._creation_order = _creation_order
|
|
_creation_order += 1
|
|
|
|
|
|
def warn_exception(func, *args, **kwargs):
|
|
"""executes the given function, catches all exceptions and converts to
|
|
a warning.
|
|
|
|
"""
|
|
try:
|
|
return func(*args, **kwargs)
|
|
except Exception:
|
|
warn("%s('%s') ignored" % sys.exc_info()[0:2])
|
|
|
|
|
|
def ellipses_string(value, len_=25):
|
|
try:
|
|
if len(value) > len_:
|
|
return "%s..." % value[0:len_]
|
|
else:
|
|
return value
|
|
except TypeError:
|
|
return value
|
|
|
|
|
|
class _hash_limit_string(compat.text_type):
|
|
"""A string subclass that can only be hashed on a maximum amount
|
|
of unique values.
|
|
|
|
This is used for warnings so that we can send out parameterized warnings
|
|
without the __warningregistry__ of the module, or the non-overridable
|
|
"once" registry within warnings.py, overloading memory,
|
|
|
|
|
|
"""
|
|
|
|
def __new__(cls, value, num, args):
|
|
interpolated = (value % args) + (
|
|
" (this warning may be suppressed after %d occurrences)" % num
|
|
)
|
|
self = super(_hash_limit_string, cls).__new__(cls, interpolated)
|
|
self._hash = hash("%s_%d" % (value, hash(interpolated) % num))
|
|
return self
|
|
|
|
def __hash__(self):
|
|
return self._hash
|
|
|
|
def __eq__(self, other):
|
|
return hash(self) == hash(other)
|
|
|
|
|
|
def warn(msg, code=None):
|
|
"""Issue a warning.
|
|
|
|
If msg is a string, :class:`.exc.SAWarning` is used as
|
|
the category.
|
|
|
|
"""
|
|
if code:
|
|
_warnings_warn(exc.SAWarning(msg, code=code))
|
|
else:
|
|
_warnings_warn(msg, exc.SAWarning)
|
|
|
|
|
|
def warn_limited(msg, args):
|
|
"""Issue a warning with a parameterized string, limiting the number
|
|
of registrations.
|
|
|
|
"""
|
|
if args:
|
|
msg = _hash_limit_string(msg, 10, args)
|
|
_warnings_warn(msg, exc.SAWarning)
|
|
|
|
|
|
def _warnings_warn(message, category=None, stacklevel=2):
|
|
|
|
# adjust the given stacklevel to be outside of SQLAlchemy
|
|
try:
|
|
frame = sys._getframe(stacklevel)
|
|
except ValueError:
|
|
# being called from less than 3 (or given) stacklevels, weird,
|
|
# but don't crash
|
|
stacklevel = 0
|
|
except:
|
|
# _getframe() doesn't work, weird interpreter issue, weird,
|
|
# ok, but don't crash
|
|
stacklevel = 0
|
|
else:
|
|
# using __name__ here requires that we have __name__ in the
|
|
# __globals__ of the decorated string functions we make also.
|
|
# we generate this using {"__name__": fn.__module__}
|
|
while frame is not None and re.match(
|
|
r"^(?:sqlalchemy\.|alembic\.)", frame.f_globals.get("__name__", "")
|
|
):
|
|
frame = frame.f_back
|
|
stacklevel += 1
|
|
|
|
if category is not None:
|
|
warnings.warn(message, category, stacklevel=stacklevel + 1)
|
|
else:
|
|
warnings.warn(message, stacklevel=stacklevel + 1)
|
|
|
|
|
|
def only_once(fn, retry_on_exception):
|
|
"""Decorate the given function to be a no-op after it is called exactly
|
|
once."""
|
|
|
|
once = [fn]
|
|
|
|
def go(*arg, **kw):
|
|
# strong reference fn so that it isn't garbage collected,
|
|
# which interferes with the event system's expectations
|
|
strong_fn = fn # noqa
|
|
if once:
|
|
once_fn = once.pop()
|
|
try:
|
|
return once_fn(*arg, **kw)
|
|
except:
|
|
if retry_on_exception:
|
|
once.insert(0, once_fn)
|
|
raise
|
|
|
|
return go
|
|
|
|
|
|
_SQLA_RE = re.compile(r"sqlalchemy/([a-z_]+/){0,2}[a-z_]+\.py")
|
|
_UNITTEST_RE = re.compile(r"unit(?:2|test2?/)")
|
|
|
|
|
|
def chop_traceback(tb, exclude_prefix=_UNITTEST_RE, exclude_suffix=_SQLA_RE):
|
|
"""Chop extraneous lines off beginning and end of a traceback.
|
|
|
|
:param tb:
|
|
a list of traceback lines as returned by ``traceback.format_stack()``
|
|
|
|
:param exclude_prefix:
|
|
a regular expression object matching lines to skip at beginning of
|
|
``tb``
|
|
|
|
:param exclude_suffix:
|
|
a regular expression object matching lines to skip at end of ``tb``
|
|
"""
|
|
start = 0
|
|
end = len(tb) - 1
|
|
while start <= end and exclude_prefix.search(tb[start]):
|
|
start += 1
|
|
while start <= end and exclude_suffix.search(tb[end]):
|
|
end -= 1
|
|
return tb[start : end + 1]
|
|
|
|
|
|
NoneType = type(None)
|
|
|
|
|
|
def attrsetter(attrname):
|
|
code = "def set(obj, value):" " obj.%s = value" % attrname
|
|
env = locals().copy()
|
|
exec(code, env)
|
|
return env["set"]
|
|
|
|
|
|
class EnsureKWArgType(type):
|
|
r"""Apply translation of functions to accept \**kw arguments if they
|
|
don't already.
|
|
|
|
"""
|
|
|
|
def __init__(cls, clsname, bases, clsdict):
|
|
fn_reg = cls.ensure_kwarg
|
|
if fn_reg:
|
|
for key in clsdict:
|
|
m = re.match(fn_reg, key)
|
|
if m:
|
|
fn = clsdict[key]
|
|
spec = compat.inspect_getfullargspec(fn)
|
|
if not spec.varkw:
|
|
clsdict[key] = wrapped = cls._wrap_w_kw(fn)
|
|
setattr(cls, key, wrapped)
|
|
super(EnsureKWArgType, cls).__init__(clsname, bases, clsdict)
|
|
|
|
def _wrap_w_kw(self, fn):
|
|
def wrap(*arg, **kw):
|
|
return fn(*arg)
|
|
|
|
return update_wrapper(wrap, fn)
|
|
|
|
|
|
def wrap_callable(wrapper, fn):
|
|
"""Augment functools.update_wrapper() to work with objects with
|
|
a ``__call__()`` method.
|
|
|
|
:param fn:
|
|
object with __call__ method
|
|
|
|
"""
|
|
if hasattr(fn, "__name__"):
|
|
return update_wrapper(wrapper, fn)
|
|
else:
|
|
_f = wrapper
|
|
_f.__name__ = fn.__class__.__name__
|
|
if hasattr(fn, "__module__"):
|
|
_f.__module__ = fn.__module__
|
|
|
|
if hasattr(fn.__call__, "__doc__") and fn.__call__.__doc__:
|
|
_f.__doc__ = fn.__call__.__doc__
|
|
elif fn.__doc__:
|
|
_f.__doc__ = fn.__doc__
|
|
|
|
return _f
|
|
|
|
|
|
def quoted_token_parser(value):
|
|
"""Parse a dotted identifier with accommodation for quoted names.
|
|
|
|
Includes support for SQL-style double quotes as a literal character.
|
|
|
|
E.g.::
|
|
|
|
>>> quoted_token_parser("name")
|
|
["name"]
|
|
>>> quoted_token_parser("schema.name")
|
|
["schema", "name"]
|
|
>>> quoted_token_parser('"Schema"."Name"')
|
|
['Schema', 'Name']
|
|
>>> quoted_token_parser('"Schema"."Name""Foo"')
|
|
['Schema', 'Name""Foo']
|
|
|
|
"""
|
|
|
|
if '"' not in value:
|
|
return value.split(".")
|
|
|
|
# 0 = outside of quotes
|
|
# 1 = inside of quotes
|
|
state = 0
|
|
result = [[]]
|
|
idx = 0
|
|
lv = len(value)
|
|
while idx < lv:
|
|
char = value[idx]
|
|
if char == '"':
|
|
if state == 1 and idx < lv - 1 and value[idx + 1] == '"':
|
|
result[-1].append('"')
|
|
idx += 1
|
|
else:
|
|
state ^= 1
|
|
elif char == "." and state == 0:
|
|
result.append([])
|
|
else:
|
|
result[-1].append(char)
|
|
idx += 1
|
|
|
|
return ["".join(token) for token in result]
|
|
|
|
|
|
def add_parameter_text(params, text):
|
|
params = _collections.to_list(params)
|
|
|
|
def decorate(fn):
|
|
doc = fn.__doc__ is not None and fn.__doc__ or ""
|
|
if doc:
|
|
doc = inject_param_text(doc, {param: text for param in params})
|
|
fn.__doc__ = doc
|
|
return fn
|
|
|
|
return decorate
|
|
|
|
|
|
def _dedent_docstring(text):
|
|
split_text = text.split("\n", 1)
|
|
if len(split_text) == 1:
|
|
return text
|
|
else:
|
|
firstline, remaining = split_text
|
|
if not firstline.startswith(" "):
|
|
return firstline + "\n" + textwrap.dedent(remaining)
|
|
else:
|
|
return textwrap.dedent(text)
|
|
|
|
|
|
def inject_docstring_text(doctext, injecttext, pos):
|
|
doctext = _dedent_docstring(doctext or "")
|
|
lines = doctext.split("\n")
|
|
if len(lines) == 1:
|
|
lines.append("")
|
|
injectlines = textwrap.dedent(injecttext).split("\n")
|
|
if injectlines[0]:
|
|
injectlines.insert(0, "")
|
|
|
|
blanks = [num for num, line in enumerate(lines) if not line.strip()]
|
|
blanks.insert(0, 0)
|
|
|
|
inject_pos = blanks[min(pos, len(blanks) - 1)]
|
|
|
|
lines = lines[0:inject_pos] + injectlines + lines[inject_pos:]
|
|
return "\n".join(lines)
|
|
|
|
|
|
_param_reg = re.compile(r"(\s+):param (.+?):")
|
|
|
|
|
|
def inject_param_text(doctext, inject_params):
|
|
doclines = collections.deque(doctext.splitlines())
|
|
lines = []
|
|
|
|
# TODO: this is not working for params like ":param case_sensitive=True:"
|
|
|
|
to_inject = None
|
|
while doclines:
|
|
line = doclines.popleft()
|
|
|
|
m = _param_reg.match(line)
|
|
|
|
if to_inject is None:
|
|
if m:
|
|
param = m.group(2).lstrip("*")
|
|
if param in inject_params:
|
|
# default indent to that of :param: plus one
|
|
indent = " " * len(m.group(1)) + " "
|
|
|
|
# but if the next line has text, use that line's
|
|
# indentation
|
|
if doclines:
|
|
m2 = re.match(r"(\s+)\S", doclines[0])
|
|
if m2:
|
|
indent = " " * len(m2.group(1))
|
|
|
|
to_inject = indent + inject_params[param]
|
|
elif m:
|
|
lines.extend(["\n", to_inject, "\n"])
|
|
to_inject = None
|
|
elif not line.rstrip():
|
|
lines.extend([line, to_inject, "\n"])
|
|
to_inject = None
|
|
elif line.endswith("::"):
|
|
# TODO: this still wont cover if the code example itself has blank
|
|
# lines in it, need to detect those via indentation.
|
|
lines.extend([line, doclines.popleft()])
|
|
continue
|
|
lines.append(line)
|
|
|
|
return "\n".join(lines)
|
|
|
|
|
|
def repr_tuple_names(names):
|
|
"""Trims a list of strings from the middle and return a string of up to
|
|
four elements. Strings greater than 11 characters will be truncated"""
|
|
if len(names) == 0:
|
|
return None
|
|
flag = len(names) <= 4
|
|
names = names[0:4] if flag else names[0:3] + names[-1:]
|
|
res = ["%s.." % name[:11] if len(name) > 11 else name for name in names]
|
|
if flag:
|
|
return ", ".join(res)
|
|
else:
|
|
return "%s, ..., %s" % (", ".join(res[0:3]), res[-1])
|
|
|
|
|
|
def has_compiled_ext():
|
|
try:
|
|
from sqlalchemy import cimmutabledict # noqa: F401
|
|
from sqlalchemy import cprocessors # noqa: F401
|
|
from sqlalchemy import cresultproxy # noqa: F401
|
|
|
|
return True
|
|
except ImportError:
|
|
return False
|