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"""Get useful information from live Python objects.
This module encapsulates the interface provided by the internal special
attributes (co_*, im_*, tb_*, etc.) in a friendlier fashion.
It also provides some help for examining source code and class layout.
Here are some of the useful functions provided by this module:
ismodule(), isclass(), ismethod(), ispackage(), isfunction(),
isgeneratorfunction(), isgenerator(), istraceback(), isframe(),
iscode(), isbuiltin(), isroutine() - check object types
getmembers() - get members of an object that satisfy a given condition
getfile(), getsourcefile(), getsource() - find an object's source code
getdoc(), getcomments() - get documentation on an object
getmodule() - determine the module that an object came from
getclasstree() - arrange classes so as to represent their hierarchy
getargvalues(), getcallargs() - get info about function arguments
getfullargspec() - same, with support for Python 3 features
formatargvalues() - format an argument spec
getouterframes(), getinnerframes() - get info about frames
currentframe() - get the current stack frame
stack(), trace() - get info about frames on the stack or in a traceback
signature() - get a Signature object for the callable
"""
# This module is in the public domain. No warranties.
__author__ = ('Ka-Ping Yee <ping@lfw.org>',
'Yury Selivanov <yselivanov@sprymix.com>')
__all__ = [
"AGEN_CLOSED",
"AGEN_CREATED",
"AGEN_RUNNING",
"AGEN_SUSPENDED",
"ArgInfo",
"Arguments",
"Attribute",
"BlockFinder",
"BoundArguments",
"BufferFlags",
"CORO_CLOSED",
"CORO_CREATED",
"CORO_RUNNING",
"CORO_SUSPENDED",
"CO_ASYNC_GENERATOR",
"CO_COROUTINE",
"CO_GENERATOR",
"CO_ITERABLE_COROUTINE",
"CO_NESTED",
"CO_NEWLOCALS",
"CO_NOFREE",
"CO_OPTIMIZED",
"CO_VARARGS",
"CO_VARKEYWORDS",
"CO_HAS_DOCSTRING",
"CO_METHOD",
"ClassFoundException",
"ClosureVars",
"EndOfBlock",
"FrameInfo",
"FullArgSpec",
"GEN_CLOSED",
"GEN_CREATED",
"GEN_RUNNING",
"GEN_SUSPENDED",
"Parameter",
"Signature",
"TPFLAGS_IS_ABSTRACT",
"Traceback",
"classify_class_attrs",
"cleandoc",
"currentframe",
"findsource",
"formatannotation",
"formatannotationrelativeto",
"formatargvalues",
"get_annotations",
"getabsfile",
"getargs",
"getargvalues",
"getasyncgenlocals",
"getasyncgenstate",
"getattr_static",
"getblock",
"getcallargs",
"getclasstree",
"getclosurevars",
"getcomments",
"getcoroutinelocals",
"getcoroutinestate",
"getdoc",
"getfile",
"getframeinfo",
"getfullargspec",
"getgeneratorlocals",
"getgeneratorstate",
"getinnerframes",
"getlineno",
"getmembers",
"getmembers_static",
"getmodule",
"getmodulename",
"getmro",
"getouterframes",
"getsource",
"getsourcefile",
"getsourcelines",
"indentsize",
"isabstract",
"isasyncgen",
"isasyncgenfunction",
"isawaitable",
"isbuiltin",
"isclass",
"iscode",
"iscoroutine",
"iscoroutinefunction",
"isdatadescriptor",
"isframe",
"isfunction",
"isgenerator",
"isgeneratorfunction",
"isgetsetdescriptor",
"ismemberdescriptor",
"ismethod",
"ismethoddescriptor",
"ismethodwrapper",
"ismodule",
"ispackage",
"isroutine",
"istraceback",
"markcoroutinefunction",
"signature",
"stack",
"trace",
"unwrap",
"walktree",
]
import abc
from annotationlib import Format, ForwardRef
from annotationlib import get_annotations # re-exported
import ast
import dis
import collections.abc
import enum
import importlib.machinery
import itertools
import linecache
import os
import re
import sys
import tokenize
import token
import types
import functools
import builtins
from keyword import iskeyword
from operator import attrgetter
from collections import namedtuple, OrderedDict
from weakref import ref as make_weakref
# Create constants for the compiler flags in Include/code.h
# We try to get them from dis to avoid duplication
mod_dict = globals()
for k, v in dis.COMPILER_FLAG_NAMES.items():
mod_dict["CO_" + v] = k
del k, v, mod_dict
# See Include/object.h
TPFLAGS_IS_ABSTRACT = 1 << 20
# ----------------------------------------------------------- type-checking
def ismodule(object):
"""Return true if the object is a module."""
return isinstance(object, types.ModuleType)
def isclass(object):
"""Return true if the object is a class."""
return isinstance(object, type)
def ismethod(object):
"""Return true if the object is an instance method."""
return isinstance(object, types.MethodType)
def ispackage(object):
"""Return true if the object is a package."""
return ismodule(object) and hasattr(object, "__path__")
def ismethoddescriptor(object):
"""Return true if the object is a method descriptor.
But not if ismethod() or isclass() or isfunction() are true.
This is new in Python 2.2, and, for example, is true of int.__add__.
An object passing this test has a __get__ attribute, but not a
__set__ attribute or a __delete__ attribute. Beyond that, the set
of attributes varies; __name__ is usually sensible, and __doc__
often is.
Methods implemented via descriptors that also pass one of the other
tests return false from the ismethoddescriptor() test, simply because
the other tests promise more -- you can, e.g., count on having the
__func__ attribute (etc) when an object passes ismethod()."""
if isclass(object) or ismethod(object) or isfunction(object):
# mutual exclusion
return False
tp = type(object)
return (hasattr(tp, "__get__")
and not hasattr(tp, "__set__")
and not hasattr(tp, "__delete__"))
def isdatadescriptor(object):
"""Return true if the object is a data descriptor.
Data descriptors have a __set__ or a __delete__ attribute. Examples are
properties (defined in Python) and getsets and members (defined in C).
Typically, data descriptors will also have __name__ and __doc__ attributes
(properties, getsets, and members have both of these attributes), but this
is not guaranteed."""
if isclass(object) or ismethod(object) or isfunction(object):
# mutual exclusion
return False
tp = type(object)
return hasattr(tp, "__set__") or hasattr(tp, "__delete__")
if hasattr(types, 'MemberDescriptorType'):
# CPython and equivalent
def ismemberdescriptor(object):
"""Return true if the object is a member descriptor.
Member descriptors are specialized descriptors defined in extension
modules."""
return isinstance(object, types.MemberDescriptorType)
else:
# Other implementations
def ismemberdescriptor(object):
"""Return true if the object is a member descriptor.
Member descriptors are specialized descriptors defined in extension
modules."""
return False
if hasattr(types, 'GetSetDescriptorType'):
# CPython and equivalent
def isgetsetdescriptor(object):
"""Return true if the object is a getset descriptor.
getset descriptors are specialized descriptors defined in extension
modules."""
return isinstance(object, types.GetSetDescriptorType)
else:
# Other implementations
def isgetsetdescriptor(object):
"""Return true if the object is a getset descriptor.
getset descriptors are specialized descriptors defined in extension
modules."""
return False
def isfunction(object):
"""Return true if the object is a user-defined function.
Function objects provide these attributes:
__doc__ documentation string
__name__ name with which this function was defined
__qualname__ qualified name of this function
__module__ name of the module the function was defined in or None
__code__ code object containing compiled function bytecode
__defaults__ tuple of any default values for arguments
__globals__ global namespace in which this function was defined
__annotations__ dict of parameter annotations
__kwdefaults__ dict of keyword only parameters with defaults
__dict__ namespace which is supporting arbitrary function attributes
__closure__ a tuple of cells or None
__type_params__ tuple of type parameters"""
return isinstance(object, types.FunctionType)
def _has_code_flag(f, flag):
"""Return true if ``f`` is a function (or a method or functools.partial
wrapper wrapping a function or a functools.partialmethod wrapping a
function) whose code object has the given ``flag``
set in its flags."""
f = functools._unwrap_partialmethod(f)
while ismethod(f):
f = f.__func__
f = functools._unwrap_partial(f)
if not (isfunction(f) or _signature_is_functionlike(f)):
return False
return bool(f.__code__.co_flags & flag)
def isgeneratorfunction(obj):
"""Return true if the object is a user-defined generator function.
Generator function objects provide the same attributes as functions.
See help(isfunction) for a list of attributes."""
return _has_code_flag(obj, CO_GENERATOR)
# A marker for markcoroutinefunction and iscoroutinefunction.
_is_coroutine_mark = object()
def _has_coroutine_mark(f):
while ismethod(f):
f = f.__func__
f = functools._unwrap_partial(f)
return getattr(f, "_is_coroutine_marker", None) is _is_coroutine_mark
def markcoroutinefunction(func):
"""
Decorator to ensure callable is recognised as a coroutine function.
"""
if hasattr(func, '__func__'):
func = func.__func__
func._is_coroutine_marker = _is_coroutine_mark
return func
def iscoroutinefunction(obj):
"""Return true if the object is a coroutine function.
Coroutine functions are normally defined with "async def" syntax, but may
be marked via markcoroutinefunction.
"""
return _has_code_flag(obj, CO_COROUTINE) or _has_coroutine_mark(obj)
def isasyncgenfunction(obj):
"""Return true if the object is an asynchronous generator function.
Asynchronous generator functions are defined with "async def"
syntax and have "yield" expressions in their body.
"""
return _has_code_flag(obj, CO_ASYNC_GENERATOR)
def isasyncgen(object):
"""Return true if the object is an asynchronous generator."""
return isinstance(object, types.AsyncGeneratorType)
def isgenerator(object):
"""Return true if the object is a generator.
Generator objects provide these attributes:
gi_code code object
gi_frame frame object or possibly None once the generator has
been exhausted
gi_running set to 1 when generator is executing, 0 otherwise
gi_suspended set to 1 when the generator is suspended at a yield point, 0 otherwise
gi_yieldfrom object being iterated by yield from or None
__iter__() defined to support iteration over container
close() raises a new GeneratorExit exception inside the
generator to terminate the iteration
send() resumes the generator and "sends" a value that becomes
the result of the current yield-expression
throw() used to raise an exception inside the generator"""
return isinstance(object, types.GeneratorType)
def iscoroutine(object):
"""Return true if the object is a coroutine."""
return isinstance(object, types.CoroutineType)
def isawaitable(object):
"""Return true if object can be passed to an ``await`` expression."""
return (isinstance(object, types.CoroutineType) or
isinstance(object, types.GeneratorType) and
bool(object.gi_code.co_flags & CO_ITERABLE_COROUTINE) or
isinstance(object, collections.abc.Awaitable))
def istraceback(object):
"""Return true if the object is a traceback.
Traceback objects provide these attributes:
tb_frame frame object at this level
tb_lasti index of last attempted instruction in bytecode
tb_lineno current line number in Python source code
tb_next next inner traceback object (called by this level)"""
return isinstance(object, types.TracebackType)
def isframe(object):
"""Return true if the object is a frame object.
Frame objects provide these attributes:
f_back next outer frame object (this frame's caller)
f_builtins built-in namespace seen by this frame
f_code code object being executed in this frame
f_globals global namespace seen by this frame
f_lasti index of last attempted instruction in bytecode
f_lineno current line number in Python source code
f_locals local namespace seen by this frame
f_trace tracing function for this frame, or None
f_trace_lines is a tracing event triggered for each source line?
f_trace_opcodes are per-opcode events being requested?
clear() used to clear all references to local variables"""
return isinstance(object, types.FrameType)
def iscode(object):
"""Return true if the object is a code object.
Code objects provide these attributes:
co_argcount number of arguments (not including *, ** args
or keyword only arguments)
co_code string of raw compiled bytecode
co_cellvars tuple of names of cell variables
co_consts tuple of constants used in the bytecode
co_filename name of file in which this code object was created
co_firstlineno number of first line in Python source code
co_flags bitmap: 1=optimized | 2=newlocals | 4=*arg | 8=**arg
| 16=nested | 32=generator | 64=nofree | 128=coroutine
| 256=iterable_coroutine | 512=async_generator
| 0x4000000=has_docstring
co_freevars tuple of names of free variables
co_posonlyargcount number of positional only arguments
co_kwonlyargcount number of keyword only arguments (not including ** arg)
co_lnotab encoded mapping of line numbers to bytecode indices
co_name name with which this code object was defined
co_names tuple of names other than arguments and function locals
co_nlocals number of local variables
co_stacksize virtual machine stack space required
co_varnames tuple of names of arguments and local variables
co_qualname fully qualified function name
co_lines() returns an iterator that yields successive bytecode ranges
co_positions() returns an iterator of source code positions for each bytecode instruction
replace() returns a copy of the code object with a new values"""
return isinstance(object, types.CodeType)
def isbuiltin(object):
"""Return true if the object is a built-in function or method.
Built-in functions and methods provide these attributes:
__doc__ documentation string
__name__ original name of this function or method
__self__ instance to which a method is bound, or None"""
return isinstance(object, types.BuiltinFunctionType)
def ismethodwrapper(object):
"""Return true if the object is a method wrapper."""
return isinstance(object, types.MethodWrapperType)
def isroutine(object):
"""Return true if the object is any kind of function or method."""
return (isbuiltin(object)
or isfunction(object)
or ismethod(object)
or ismethoddescriptor(object)
or ismethodwrapper(object)
or isinstance(object, functools._singledispatchmethod_get))
def isabstract(object):
"""Return true if the object is an abstract base class (ABC)."""
if not isinstance(object, type):
return False
if object.__flags__ & TPFLAGS_IS_ABSTRACT:
return True
if not issubclass(type(object), abc.ABCMeta):
return False
if hasattr(object, '__abstractmethods__'):
# It looks like ABCMeta.__new__ has finished running;
# TPFLAGS_IS_ABSTRACT should have been accurate.
return False
# It looks like ABCMeta.__new__ has not finished running yet; we're
# probably in __init_subclass__. We'll look for abstractmethods manually.
for name, value in object.__dict__.items():
if getattr(value, "__isabstractmethod__", False):
return True
for base in object.__bases__:
for name in getattr(base, "__abstractmethods__", ()):
value = getattr(object, name, None)
if getattr(value, "__isabstractmethod__", False):
return True
return False
def _getmembers(object, predicate, getter):
results = []
processed = set()
names = dir(object)
if isclass(object):
mro = getmro(object)
# add any DynamicClassAttributes to the list of names if object is a class;
# this may result in duplicate entries if, for example, a virtual
# attribute with the same name as a DynamicClassAttribute exists
try:
for base in object.__bases__:
for k, v in base.__dict__.items():
if isinstance(v, types.DynamicClassAttribute):
names.append(k)
except AttributeError:
pass
else:
mro = ()
for key in names:
# First try to get the value via getattr. Some descriptors don't
# like calling their __get__ (see bug #1785), so fall back to
# looking in the __dict__.
try:
value = getter(object, key)
# handle the duplicate key
if key in processed:
raise AttributeError
except AttributeError:
for base in mro:
if key in base.__dict__:
value = base.__dict__[key]
break
else:
# could be a (currently) missing slot member, or a buggy
# __dir__; discard and move on
continue
if not predicate or predicate(value):
results.append((key, value))
processed.add(key)
results.sort(key=lambda pair: pair[0])
return results
def getmembers(object, predicate=None):
"""Return all members of an object as (name, value) pairs sorted by name.
Optionally, only return members that satisfy a given predicate."""
return _getmembers(object, predicate, getattr)
def getmembers_static(object, predicate=None):
"""Return all members of an object as (name, value) pairs sorted by name
without triggering dynamic lookup via the descriptor protocol,
__getattr__ or __getattribute__. Optionally, only return members that
satisfy a given predicate.
Note: this function may not be able to retrieve all members
that getmembers can fetch (like dynamically created attributes)
and may find members that getmembers can't (like descriptors
that raise AttributeError). It can also return descriptor objects
instead of instance members in some cases.
"""
return _getmembers(object, predicate, getattr_static)
Attribute = namedtuple('Attribute', 'name kind defining_class object')
def classify_class_attrs(cls):
"""Return list of attribute-descriptor tuples.
For each name in dir(cls), the return list contains a 4-tuple
with these elements:
0. The name (a string).
1. The kind of attribute this is, one of these strings:
'class method' created via classmethod()
'static method' created via staticmethod()
'property' created via property()
'method' any other flavor of method or descriptor
'data' not a method
2. The class which defined this attribute (a class).
3. The object as obtained by calling getattr; if this fails, or if the
resulting object does not live anywhere in the class' mro (including
metaclasses) then the object is looked up in the defining class's
dict (found by walking the mro).
If one of the items in dir(cls) is stored in the metaclass it will now
be discovered and not have None be listed as the class in which it was
defined. Any items whose home class cannot be discovered are skipped.
"""
mro = getmro(cls)
metamro = getmro(type(cls)) # for attributes stored in the metaclass
metamro = tuple(cls for cls in metamro if cls not in (type, object))
class_bases = (cls,) + mro
all_bases = class_bases + metamro
names = dir(cls)
# :dd any DynamicClassAttributes to the list of names;
# this may result in duplicate entries if, for example, a virtual
# attribute with the same name as a DynamicClassAttribute exists.
for base in mro:
for k, v in base.__dict__.items():
if isinstance(v, types.DynamicClassAttribute) and v.fget is not None:
names.append(k)
result = []
processed = set()
for name in names:
# Get the object associated with the name, and where it was defined.
# Normal objects will be looked up with both getattr and directly in
# its class' dict (in case getattr fails [bug #1785], and also to look
# for a docstring).
# For DynamicClassAttributes on the second pass we only look in the
# class's dict.
#
# Getting an obj from the __dict__ sometimes reveals more than
# using getattr. Static and class methods are dramatic examples.
homecls = None
get_obj = None
dict_obj = None
if name not in processed:
try:
if name == '__dict__':
raise Exception("__dict__ is special, don't want the proxy")
get_obj = getattr(cls, name)
except Exception:
pass
else:
homecls = getattr(get_obj, "__objclass__", homecls)
if homecls not in class_bases:
# if the resulting object does not live somewhere in the
# mro, drop it and search the mro manually
homecls = None
last_cls = None
# first look in the classes
for srch_cls in class_bases:
srch_obj = getattr(srch_cls, name, None)
if srch_obj is get_obj:
last_cls = srch_cls
# then check the metaclasses
for srch_cls in metamro:
try:
srch_obj = srch_cls.__getattr__(cls, name)
except AttributeError:
continue
if srch_obj is get_obj:
last_cls = srch_cls
if last_cls is not None:
homecls = last_cls
for base in all_bases:
if name in base.__dict__:
dict_obj = base.__dict__[name]
if homecls not in metamro:
homecls = base
break
if homecls is None:
# unable to locate the attribute anywhere, most likely due to
# buggy custom __dir__; discard and move on
continue
obj = get_obj if get_obj is not None else dict_obj
# Classify the object or its descriptor.
if isinstance(dict_obj, (staticmethod, types.BuiltinMethodType)):
kind = "static method"
obj = dict_obj
elif isinstance(dict_obj, (classmethod, types.ClassMethodDescriptorType)):
kind = "class method"
obj = dict_obj
elif isinstance(dict_obj, property):
kind = "property"
obj = dict_obj
elif isroutine(obj):
kind = "method"
else:
kind = "data"
result.append(Attribute(name, kind, homecls, obj))
processed.add(name)
return result
# ----------------------------------------------------------- class helpers
def getmro(cls):
"Return tuple of base classes (including cls) in method resolution order."
return cls.__mro__
# -------------------------------------------------------- function helpers
def unwrap(func, *, stop=None):
"""Get the object wrapped by *func*.
Follows the chain of :attr:`__wrapped__` attributes returning the last
object in the chain.
*stop* is an optional callback accepting an object in the wrapper chain
as its sole argument that allows the unwrapping to be terminated early if
the callback returns a true value. If the callback never returns a true
value, the last object in the chain is returned as usual. For example,
:func:`signature` uses this to stop unwrapping if any object in the
chain has a ``__signature__`` attribute defined.
:exc:`ValueError` is raised if a cycle is encountered.
"""
f = func # remember the original func for error reporting
# Memoise by id to tolerate non-hashable objects, but store objects to
# ensure they aren't destroyed, which would allow their IDs to be reused.
memo = {id(f): f}
recursion_limit = sys.getrecursionlimit()
while not isinstance(func, type) and hasattr(func, '__wrapped__'):
if stop is not None and stop(func):
break
func = func.__wrapped__
id_func = id(func)
if (id_func in memo) or (len(memo) >= recursion_limit):
raise ValueError('wrapper loop when unwrapping {!r}'.format(f))
memo[id_func] = func
return func
# -------------------------------------------------- source code extraction
def indentsize(line):
"""Return the indent size, in spaces, at the start of a line of text."""
expline = line.expandtabs()
return len(expline) - len(expline.lstrip())
def _findclass(func):
cls = sys.modules.get(func.__module__)
if cls is None:
return None
for name in func.__qualname__.split('.')[:-1]:
cls = getattr(cls, name)
if not isclass(cls):
return None
return cls
def _finddoc(obj):
if isclass(obj):
for base in obj.__mro__:
if base is not object:
try:
doc = base.__doc__
except AttributeError:
continue
if doc is not None:
return doc
return None
if ismethod(obj):
name = obj.__func__.__name__
self = obj.__self__
if (isclass(self) and
getattr(getattr(self, name, None), '__func__') is obj.__func__):
# classmethod
cls = self
else:
cls = self.__class__
elif isfunction(obj):
name = obj.__name__
cls = _findclass(obj)
if cls is None or getattr(cls, name) is not obj:
return None
elif isbuiltin(obj):
name = obj.__name__
self = obj.__self__
if (isclass(self) and
self.__qualname__ + '.' + name == obj.__qualname__):
# classmethod
cls = self
else:
cls = self.__class__
# Should be tested before isdatadescriptor().
elif isinstance(obj, property):
name = obj.__name__
cls = _findclass(obj.fget)
if cls is None or getattr(cls, name) is not obj:
return None
elif ismethoddescriptor(obj) or isdatadescriptor(obj):
name = obj.__name__
cls = obj.__objclass__
if getattr(cls, name) is not obj:
return None
if ismemberdescriptor(obj):
slots = getattr(cls, '__slots__', None)
if isinstance(slots, dict) and name in slots:
return slots[name]
else:
return None
for base in cls.__mro__:
try:
doc = getattr(base, name).__doc__
except AttributeError:
continue
if doc is not None:
return doc
return None
def getdoc(object):
"""Get the documentation string for an object.
All tabs are expanded to spaces. To clean up docstrings that are
indented to line up with blocks of code, any whitespace than can be
uniformly removed from the second line onwards is removed."""
try:
doc = object.__doc__
except AttributeError:
return None
if doc is None:
try:
doc = _finddoc(object)
except (AttributeError, TypeError):
return None
if not isinstance(doc, str):
return None
return cleandoc(doc)
def cleandoc(doc):
"""Clean up indentation from docstrings.
Any whitespace that can be uniformly removed from the second line
onwards is removed."""
lines = doc.expandtabs().split('\n')
# Find minimum indentation of any non-blank lines after first line.
margin = sys.maxsize
for line in lines[1:]:
content = len(line.lstrip(' '))
if content:
indent = len(line) - content
margin = min(margin, indent)
# Remove indentation.
if lines:
lines[0] = lines[0].lstrip(' ')
if margin < sys.maxsize:
for i in range(1, len(lines)):
lines[i] = lines[i][margin:]
# Remove any trailing or leading blank lines.
while lines and not lines[-1]:
lines.pop()
while lines and not lines[0]:
lines.pop(0)
return '\n'.join(lines)
def getfile(object):
"""Work out which source or compiled file an object was defined in."""
if ismodule(object):
if getattr(object, '__file__', None):
return object.__file__
raise TypeError('{!r} is a built-in module'.format(object))
if isclass(object):
if hasattr(object, '__module__'):
module = sys.modules.get(object.__module__)
if getattr(module, '__file__', None):
return module.__file__
if object.__module__ == '__main__':
raise OSError('source code not available')
raise TypeError('{!r} is a built-in class'.format(object))
if ismethod(object):
object = object.__func__
if isfunction(object):
object = object.__code__
if istraceback(object):
object = object.tb_frame
if isframe(object):
object = object.f_code
if iscode(object):
return object.co_filename
raise TypeError('module, class, method, function, traceback, frame, or '
'code object was expected, got {}'.format(
type(object).__name__))
def getmodulename(path):
"""Return the module name for a given file, or None."""
fname = os.path.basename(path)
# Check for paths that look like an actual module file
suffixes = [(-len(suffix), suffix)
for suffix in importlib.machinery.all_suffixes()]
suffixes.sort() # try longest suffixes first, in case they overlap
for neglen, suffix in suffixes:
if fname.endswith(suffix):
return fname[:neglen]
return None
def getsourcefile(object):
"""Return the filename that can be used to locate an object's source.
Return None if no way can be identified to get the source.
"""
filename = getfile(object)
all_bytecode_suffixes = importlib.machinery.BYTECODE_SUFFIXES[:]
if any(filename.endswith(s) for s in all_bytecode_suffixes):
filename = (os.path.splitext(filename)[0] +
importlib.machinery.SOURCE_SUFFIXES[0])
elif any(filename.endswith(s) for s in
importlib.machinery.EXTENSION_SUFFIXES):
return None
elif filename.endswith(".fwork"):
# Apple mobile framework markers are another type of non-source file
return None
# return a filename found in the linecache even if it doesn't exist on disk
if filename in linecache.cache:
return filename
if os.path.exists(filename):
return filename
# only return a non-existent filename if the module has a PEP 302 loader
module = getmodule(object, filename)
if getattr(module, '__loader__', None) is not None:
return filename
elif getattr(getattr(module, "__spec__", None), "loader", None) is not None:
return filename
def getabsfile(object, _filename=None):
"""Return an absolute path to the source or compiled file for an object.
The idea is for each object to have a unique origin, so this routine
normalizes the result as much as possible."""
if _filename is None:
_filename = getsourcefile(object) or getfile(object)
return os.path.normcase(os.path.abspath(_filename))
modulesbyfile = {}
_filesbymodname = {}
def getmodule(object, _filename=None):
"""Return the module an object was defined in, or None if not found."""
if ismodule(object):
return object
if hasattr(object, '__module__'):
return sys.modules.get(object.__module__)
# Try the filename to modulename cache
if _filename is not None and _filename in modulesbyfile:
return sys.modules.get(modulesbyfile[_filename])
# Try the cache again with the absolute file name
try:
file = getabsfile(object, _filename)
except (TypeError, FileNotFoundError):
return None
if file in modulesbyfile:
return sys.modules.get(modulesbyfile[file])
# Update the filename to module name cache and check yet again
# Copy sys.modules in order to cope with changes while iterating
for modname, module in sys.modules.copy().items():
if ismodule(module) and hasattr(module, '__file__'):
f = module.__file__
if f == _filesbymodname.get(modname, None):
# Have already mapped this module, so skip it
continue
_filesbymodname[modname] = f
f = getabsfile(module)
# Always map to the name the module knows itself by
modulesbyfile[f] = modulesbyfile[
os.path.realpath(f)] = module.__name__
if file in modulesbyfile:
return sys.modules.get(modulesbyfile[file])
# Check the main module
main = sys.modules['__main__']
if not hasattr(object, '__name__'):
return None
if hasattr(main, object.__name__):
mainobject = getattr(main, object.__name__)
if mainobject is object:
return main
# Check builtins
builtin = sys.modules['builtins']
if hasattr(builtin, object.__name__):
builtinobject = getattr(builtin, object.__name__)
if builtinobject is object:
return builtin
class ClassFoundException(Exception):
pass
def findsource(object):
"""Return the entire source file and starting line number for an object.
The argument may be a module, class, method, function, traceback, frame,
or code object. The source code is returned as a list of all the lines
in the file and the line number indexes a line in that list. An OSError
is raised if the source code cannot be retrieved."""
file = getsourcefile(object)
if file:
# Invalidate cache if needed.
linecache.checkcache(file)
else:
file = getfile(object)
# Allow filenames in form of "<something>" to pass through.
# `doctest` monkeypatches `linecache` module to enable
# inspection, so let `linecache.getlines` to be called.
if (not (file.startswith('<') and file.endswith('>'))) or file.endswith('.fwork'):
raise OSError('source code not available')
module = getmodule(object, file)
if module:
lines = linecache.getlines(file, module.__dict__)
if not lines and file.startswith('<') and hasattr(object, "__code__"):
lines = linecache._getlines_from_code(object.__code__)
else:
lines = linecache.getlines(file)
if not lines:
raise OSError('could not get source code')
if ismodule(object):
return lines, 0
if isclass(object):
try:
lnum = vars(object)['__firstlineno__'] - 1
except (TypeError, KeyError):
raise OSError('source code not available')
if lnum >= len(lines):
raise OSError('lineno is out of bounds')
return lines, lnum
if ismethod(object):
object = object.__func__
if isfunction(object):
object = object.__code__
if istraceback(object):
object = object.tb_frame
if isframe(object):
object = object.f_code
if iscode(object):