"""
Pdb debugger class.
This is an extension to PDB which adds a number of new features.
Note that there is also the `IPython.terminal.debugger` class which provides UI
improvements.
We also strongly recommend to use this via the `ipdb` package, which provides
extra configuration options.
Among other things, this subclass of PDB:
- supports many IPython magics like pdef/psource
- hide frames in tracebacks based on `__tracebackhide__`
- allows to skip frames based on `__debuggerskip__`
Global Configuration
--------------------
The IPython debugger will by read the global ``~/.pdbrc`` file.
That is to say you can list all commands supported by ipdb in your `~/.pdbrc`
configuration file, to globally configure pdb.
Example::
# ~/.pdbrc
skip_predicates debuggerskip false
skip_hidden false
context 25
Features
--------
The IPython debugger can hide and skip frames when printing or moving through
the stack. This can have a performance impact, so can be configures.
The skipping and hiding frames are configurable via the `skip_predicates`
command.
By default, frames from readonly files will be hidden, frames containing
``__tracebackhide__ = True`` will be hidden.
Frames containing ``__debuggerskip__`` will be stepped over, frames whose parent
frames value of ``__debuggerskip__`` is ``True`` will also be skipped.
>>> def helpers_helper():
... pass
...
... def helper_1():
... print("don't step in me")
... helpers_helpers() # will be stepped over unless breakpoint set.
...
...
... def helper_2():
... print("in me neither")
...
One can define a decorator that wraps a function between the two helpers:
>>> def pdb_skipped_decorator(function):
...
...
... def wrapped_fn(*args, **kwargs):
... __debuggerskip__ = True
... helper_1()
... __debuggerskip__ = False
... result = function(*args, **kwargs)
... __debuggerskip__ = True
... helper_2()
... # setting __debuggerskip__ to False again is not necessary
... return result
...
... return wrapped_fn
When decorating a function, ipdb will directly step into ``bar()`` by
default:
>>> @foo_decorator
... def bar(x, y):
... return x * y
You can toggle the behavior with
ipdb> skip_predicates debuggerskip false
or configure it in your ``.pdbrc``
License
-------
Modified from the standard pdb.Pdb class to avoid including readline, so that
the command line completion of other programs which include this isn't
damaged.
In the future, this class will be expanded with improvements over the standard
pdb.
The original code in this file is mainly lifted out of cmd.py in Python 2.2,
with minor changes. Licensing should therefore be under the standard Python
terms. For details on the PSF (Python Software Foundation) standard license,
see:
https://docs.python.org/2/license.html
All the changes since then are under the same license as IPython.
"""
# *****************************************************************************
#
# This file is licensed under the PSF license.
#
# Copyright (C) 2001 Python Software Foundation, www.python.org
# Copyright (C) 2005-2006 Fernando Perez. <fperez@colorado.edu>
#
#
# *****************************************************************************
from __future__ import annotations
import inspect
import linecache
import os
import re
import sys
import warnings
from contextlib import contextmanager
from functools import lru_cache
from IPython import get_ipython
from IPython.core.debugger_backport import PdbClosureBackport
from IPython.utils import PyColorize
from IPython.utils.PyColorize import TokenStream
from typing import TYPE_CHECKING
from types import FrameType
# We have to check this directly from sys.argv, config struct not yet available
from pdb import Pdb as _OldPdb
from pygments.token import Token
if sys.version_info < (3, 13):
class OldPdb(PdbClosureBackport, _OldPdb):
pass
else:
OldPdb = _OldPdb
if TYPE_CHECKING:
# otherwise circular import
from IPython.core.interactiveshell import InteractiveShell
# skip module docstests
__skip_doctest__ = True
prompt = "ipdb> "
# Allow the set_trace code to operate outside of an ipython instance, even if
# it does so with some limitations. The rest of this support is implemented in
# the Tracer constructor.
DEBUGGERSKIP = "__debuggerskip__"
# this has been implemented in Pdb in Python 3.13 (https://github.com/python/cpython/pull/106676
# on lower python versions, we backported the feature.
CHAIN_EXCEPTIONS = sys.version_info < (3, 13)
def BdbQuit_excepthook(et, ev, tb, excepthook=None):
"""Exception hook which handles `BdbQuit` exceptions.
All other exceptions are processed using the `excepthook`
parameter.
"""
raise ValueError(
"`BdbQuit_excepthook` is deprecated since version 5.1. It is still around only because it is still imported by ipdb.",
)
RGX_EXTRA_INDENT = re.compile(r"(?<=\n)\s+")
def strip_indentation(multiline_string):
return RGX_EXTRA_INDENT.sub("", multiline_string)
def decorate_fn_with_doc(new_fn, old_fn, additional_text=""):
"""Make new_fn have old_fn's doc string. This is particularly useful
for the ``do_...`` commands that hook into the help system.
Adapted from from a comp.lang.python posting
by Duncan Booth."""
def wrapper(*args, **kw):
return new_fn(*args, **kw)
if old_fn.__doc__:
wrapper.__doc__ = strip_indentation(old_fn.__doc__) + additional_text
return wrapper
class Pdb(OldPdb):
"""Modified Pdb class, does not load readline.
for a standalone version that uses prompt_toolkit, see
`IPython.terminal.debugger.TerminalPdb` and
`IPython.terminal.debugger.set_trace()`
This debugger can hide and skip frames that are tagged according to some predicates.
See the `skip_predicates` commands.
"""
shell: InteractiveShell
_theme_name: str
_context: int
_chained_exceptions: tuple[Exception, ...]
_chained_exception_index: int
if CHAIN_EXCEPTIONS:
MAX_CHAINED_EXCEPTION_DEPTH = 999
default_predicates = {
"tbhide": True,
"readonly": False,
"ipython_internal": True,
"debuggerskip": True,
}
def __init__(
self,
completekey=None,
stdin=None,
stdout=None,
context: int | None | str = 5,
**kwargs,
):
"""Create a new IPython debugger.
Parameters
----------
completekey : default None
Passed to pdb.Pdb.
stdin : default None
Passed to pdb.Pdb.
stdout : default None
Passed to pdb.Pdb.
context : int
Number of lines of source code context to show when
displaying stacktrace information.
**kwargs
Passed to pdb.Pdb.
Notes
-----
The possibilities are python version dependent, see the python
docs for more info.
"""
# ipdb issue, see https://github.com/ipython/ipython/issues/14811
if context is None:
context = 5
if isinstance(context, str):
context = int(context)
self.context = context
# `kwargs` ensures full compatibility with stdlib's `pdb.Pdb`.
OldPdb.__init__(self, completekey, stdin, stdout, **kwargs)
# Python 3.15+ should define this, so no need to initialize
# this avoids some getattr(self, 'curframe')
if sys.version_info < (3, 15):
self.curframe = None
# IPython changes...
self.shell = get_ipython()
if self.shell is None:
save_main = sys.modules["__main__"]
# No IPython instance running, we must create one
from IPython.terminal.interactiveshell import TerminalInteractiveShell
self.shell = TerminalInteractiveShell.instance()
# needed by any code which calls __import__("__main__") after
# the debugger was entered. See also #9941.
sys.modules["__main__"] = save_main
self.aliases = {}
theme_name = self.shell.colors
assert isinstance(theme_name, str)
assert theme_name.lower() == theme_name
# Add a python parser so we can syntax highlight source while
# debugging.
self.parser = PyColorize.Parser(theme_name=theme_name)
self.set_theme_name(theme_name)
# Set the prompt - the default prompt is '(Pdb)'
self.prompt = prompt
self.skip_hidden = True
self.report_skipped = True
# list of predicates we use to skip frames
self._predicates = self.default_predicates
if CHAIN_EXCEPTIONS:
self._chained_exceptions = tuple()
self._chained_exception_index = 0
@property
def context(self) -> int:
return self._context
@context.setter
def context(self, value: int | str) -> None:
# ipdb issue see https://github.com/ipython/ipython/issues/14811
if not isinstance(value, int):
value = int(value)
assert isinstance(value, int)
assert value >= 0
self._context = value
def set_theme_name(self, name):
assert name.lower() == name
assert isinstance(name, str)
self._theme_name = name
self.parser.theme_name = name
@property
def theme(self):
return PyColorize.theme_table[self._theme_name]
#
def set_colors(self, scheme):
"""Shorthand access to the color table scheme selector method."""
warnings.warn(
"set_colors is deprecated since IPython 9.0, use set_theme_name instead",
DeprecationWarning,
stacklevel=2,
)
assert scheme == scheme.lower()
self._theme_name = scheme.lower()
self.parser.theme_name = scheme.lower()
def set_trace(self, frame=None):
if frame is None:
frame = sys._getframe().f_back
self.initial_frame = frame
return super().set_trace(frame)
def get_stack(self, *args, **kwargs):
stack, pos = super().get_stack(*args, **kwargs)
if len(stack) >= 0 and self._is_internal_frame(stack[0][0]):
stack.pop(0)
pos -= 1
return stack, pos
def _is_internal_frame(self, frame):
"""Determine if this frame should be skipped as internal"""
filename = frame.f_code.co_filename
# Skip bdb.py runcall and internal operations
if filename.endswith("bdb.py"):
func_name = frame.f_code.co_name
# Skip internal bdb operations but allow breakpoint hits
if func_name in ("runcall", "run", "runeval"):
return True
return False
def _hidden_predicate(self, frame):
"""
Given a frame return whether it it should be hidden or not by IPython.
"""
if self._predicates["readonly"]:
fname = frame.f_code.co_filename
# we need to check for file existence and interactively define
# function would otherwise appear as RO.
if os.path.isfile(fname) and not os.access(fname, os.W_OK):
return True
if self._predicates["tbhide"]:
if frame in (self.curframe, getattr(self, "initial_frame", None)):
return False
frame_locals = self._get_frame_locals(frame)
if "__tracebackhide__" not in frame_locals:
return False
return frame_locals["__tracebackhide__"]
return False
def hidden_frames(self, stack):
"""
Given an index in the stack return whether it should be skipped.
This is used in up/down and where to skip frames.
"""
# The f_locals dictionary is updated from the actual frame
# locals whenever the .f_locals accessor is called, so we
# avoid calling it here to preserve self.curframe_locals.
# Furthermore, there is no good reason to hide the current frame.
ip_hide = [self._hidden_predicate(s[0]) for s in stack]
ip_start = [i for i, s in enumerate(ip_hide) if s == "__ipython_bottom__"]
if ip_start and self._predicates["ipython_internal"]:
ip_hide = [h if i > ip_start[0] else True for (i, h) in enumerate(ip_hide)]
return ip_hide
if CHAIN_EXCEPTIONS:
def _get_tb_and_exceptions(self, tb_or_exc):
"""
Given a tracecack or an exception, return a tuple of chained exceptions
and current traceback to inspect.
This will deal with selecting the right ``__cause__`` or ``__context__``
as well as handling cycles, and return a flattened list of exceptions we
can jump to with do_exceptions.
"""
_exceptions = []
if isinstance(tb_or_exc, BaseException):
traceback, current = tb_or_exc.__traceback__, tb_or_exc
while current is not None:
if current in _exceptions:
break
_exceptions.append(current)
if current.__cause__ is not None:
current = current.__cause__
elif (
current.__context__ is not None
and not current.__suppress_context__
):
current = current.__context__
if len(_exceptions) >= self.MAX_CHAINED_EXCEPTION_DEPTH:
self.message(
f"More than {self.MAX_CHAINED_EXCEPTION_DEPTH}"
" chained exceptions found, not all exceptions"
"will be browsable with `exceptions`."
)
break
else:
traceback = tb_or_exc
return tuple(reversed(_exceptions)), traceback
@contextmanager
def _hold_exceptions(self, exceptions):
"""
Context manager to ensure proper cleaning of exceptions references
When given a chained exception instead of a traceback,
pdb may hold references to many objects which may leak memory.
We use this context manager to make sure everything is properly cleaned
"""
try:
self._chained_exceptions = exceptions
self._chained_exception_index = len(exceptions) - 1
yield
finally:
# we can't put those in forget as otherwise they would
# be cleared on exception change
self._chained_exceptions = tuple()
self._chained_exception_index = 0
def do_exceptions(self, arg):
"""exceptions [number]
List or change current exception in an exception chain.
Without arguments, list all the current exception in the exception
chain. Exceptions will be numbered, with the current exception indicated
with an arrow.
If given an integer as argument, switch to the exception at that index.
"""
if not self._chained_exceptions:
self.message(
"Did not find chained exceptions. To move between"
" exceptions, pdb/post_mortem must be given an exception"
" object rather than a traceback."
)
return
if not arg:
for ix, exc in enumerate(self._chained_exceptions):
prompt = ">" if ix == self._chained_exception_index else " "
rep = repr(exc)
if len(rep) > 80:
rep = rep[:77] + "..."
indicator = (
" -"
if self._chained_exceptions[ix].__traceback__ is None
else f"{ix:>3}"
)
self.message(f"{prompt} {indicator} {rep}")
else:
try:
number = int(arg)
except ValueError:
self.error("Argument must be an integer")
return
if 0 <= number < len(self._chained_exceptions):
if self._chained_exceptions[number].__traceback__ is None:
self.error(
"This exception does not have a traceback, cannot jump to it"
)
return
self._chained_exception_index = number
self.setup(None, self._chained_exceptions[number].__traceback__)
self.print_stack_entry(self.stack[self.curindex])
else:
self.error("No exception with that number")
def interaction(self, frame, tb_or_exc):
try:
if CHAIN_EXCEPTIONS:
# this context manager is part of interaction in 3.13
_chained_exceptions, tb = self._get_tb_and_exceptions(tb_or_exc)
if isinstance(tb_or_exc, BaseException):
assert tb is not None, "main exception must have a traceback"
with self._hold_exceptions(_chained_exceptions):
OldPdb.interaction(self, frame, tb)
else:
OldPdb.interaction(self, frame, tb_or_exc)
except KeyboardInterrupt:
self.stdout.write("\n" + self.shell.get_exception_only())
def precmd(self, line):
"""Perform useful escapes on the command before it is executed."""
if line.endswith("??"):
line = "pinfo2 " + line[:-2]
elif line.endswith("?"):
line = "pinfo " + line[:-1]
line = super().precmd(line)
return line
def new_do_quit(self, arg):
return OldPdb.do_quit(self, arg)
do_q = do_quit = decorate_fn_with_doc(new_do_quit, OldPdb.do_quit)
def print_stack_trace(self, context: int | None = None):
if context is None:
context = self.context
try:
skipped = 0
to_print = ""
for hidden, frame_lineno in zip(self.hidden_frames(self.stack), self.stack):
if hidden and self.skip_hidden:
skipped += 1
continue
if skipped:
to_print += self.theme.format(
[
(
Token.ExcName,
f" [... skipping {skipped} hidden frame(s)]",
),
(Token, "\n"),
]
)
skipped = 0
to_print += self.format_stack_entry(frame_lineno)
if skipped:
to_print += self.theme.format(
[
(
Token.ExcName,
f" [... skipping {skipped} hidden frame(s)]",
),
(Token, "\n"),
]
)
print(to_print, file=self.stdout)
except KeyboardInterrupt:
pass
def print_stack_entry(
self, frame_lineno: tuple[FrameType, int], prompt_prefix: str = "\n-> "
) -> None:
"""
Overwrite print_stack_entry from superclass (PDB)
"""
print(self.format_stack_entry(frame_lineno, ""), file=self.stdout)
frame, lineno = frame_lineno
filename = frame.f_code.co_filename
self.shell.hooks.synchronize_with_editor(filename, lineno, 0)
def _get_frame_locals(self, frame):
""" "
Accessing f_local of current frame reset the namespace, so we want to avoid
that or the following can happen
ipdb> foo
"old"
ipdb> foo = "new"
ipdb> foo
"new"
ipdb> where
ipdb> foo
"old"
So if frame is self.current_frame we instead return self.curframe_locals
"""
if frame is self.curframe:
return self.curframe_locals
else:
return frame.f_locals
def format_stack_entry(
self,
frame_lineno: tuple[FrameType, int], # type: ignore[override] # stubs are wrong
lprefix: str = ": ",
) -> str:
"""
overwrite from super class so must -> str
"""
context = self.context
try:
context = int(context)
if context <= 0:
print("Context must be a positive integer", file=self.stdout)
except (TypeError, ValueError):
print("Context must be a positive integer", file=self.stdout)
import reprlib
ret_tok = []
frame, lineno = frame_lineno
return_value = ""
loc_frame = self._get_frame_locals(frame)
if "__return__" in loc_frame:
rv = loc_frame["__return__"]
# return_value += '->'
return_value += reprlib.repr(rv) + "\n"
ret_tok.extend([(Token, return_value)])
# s = filename + '(' + `lineno` + ')'
filename = self.canonic(frame.f_code.co_filename)
link_tok = (Token.FilenameEm, filename)
if frame.f_code.co_name:
func = frame.f_code.co_name
else:
func = "<lambda>"
call_toks = []
if func != "?":
if "__args__" in loc_frame:
args = reprlib.repr(loc_frame["__args__"])
else:
args = "()"
call_toks = [(Token.VName, func), (Token.ValEm, args)]
# The level info should be generated in the same format pdb uses, to
# avoid breaking the pdbtrack functionality of python-mode in *emacs.
if frame is self.curframe:
ret_tok.append((Token.CurrentFrame, self.theme.make_arrow(2)))
else:
ret_tok.append((Token, " "))
ret_tok.extend(
[
link_tok,
(Token, "("),
(Token.Lineno, str(lineno)),
(Token, ")"),
*call_toks,
(Token, "\n"),
]
)
start = lineno - 1 - context // 2
lines = linecache.getlines(filename)
start = min(start, len(lines) - context)
start = max(start, 0)
lines = lines[start : start + context]
for i, line in enumerate(lines):
show_arrow = start + 1 + i == lineno
bp, num, colored_line = self.__line_content(
filename,
start + 1 + i,
line,
arrow=show_arrow,
)
if frame is self.curframe or show_arrow:
rlt = [
bp,
(Token.LinenoEm, num),
(Token, " "),
# TODO: investigate Toke.Line here, likely LineEm,
# Token is problematic here as line is already colored, a
# and this changes the full style of the colored line.
# ideally, __line_content returns the token and we modify the style.
(Token, colored_line),
]
else:
rlt = [
bp,
(Token.Lineno, num),
(Token, " "),
# TODO: investigate Toke.Line here, likely Line
# Token is problematic here as line is already colored, a
# and this changes the full style of the colored line.
# ideally, __line_content returns the token and we modify the style.
(Token.Line, colored_line),
]
ret_tok.extend(rlt)
return self.theme.format(ret_tok)
def __line_content(
self, filename: str, lineno: int, line: str, arrow: bool = False
):
bp_mark = ""
BreakpointToken = Token.Breakpoint
new_line, err = self.parser.format2(line, "str")
if not err:
assert new_line is not None
line = new_line
bp = None
if lineno in self.get_file_breaks(filename):
bps = self.get_breaks(filename, lineno)
bp = bps[-1]
if bp:
bp_mark = str(bp.number)
BreakpointToken = Token.Breakpoint.Enabled
if not bp.enabled:
BreakpointToken = Token.Breakpoint.Disabled
numbers_width = 7
if arrow:
# This is the line with the error
pad = numbers_width - len(str(lineno)) - len(bp_mark)
num = "%s%s" % (self.theme.make_arrow(pad), str(lineno))
else:
num = "%*s" % (numbers_width - len(bp_mark), str(lineno))
bp_str = (BreakpointToken, bp_mark)
return (bp_str, num, line)
def print_list_lines(self, filename: str, first: int, last: int) -> None:
"""The printing (as opposed to the parsing part of a 'list'
command."""
toks: TokenStream = []
try:
if filename == "<string>" and hasattr(self, "_exec_filename"):
filename = self._exec_filename
for lineno in range(first, last + 1):
line = linecache.getline(filename, lineno)
if not line:
break
assert self.curframe is not None
if lineno == self.curframe.f_lineno:
bp, num, colored_line = self.__line_content(
filename, lineno, line, arrow=True
)
toks.extend(
[
bp,
(Token.LinenoEm, num),
(Token, " "),
# TODO: investigate Token.Line here
(Token, colored_line),
]
)
else:
bp, num, colored_line = self.__line_content(
filename, lineno, line, arrow=False
)
toks.extend(
[
bp,
(Token.Lineno, num),
(Token, " "),
(Token, colored_line),
]
)
self.lineno = lineno
print(self.theme.format(toks), file=self.stdout)
except KeyboardInterrupt:
pass
def do_skip_predicates(self, args):
"""
Turn on/off individual predicates as to whether a frame should be hidden/skip.
The global option to skip (or not) hidden frames is set with skip_hidden
To change the value of a predicate
skip_predicates key [true|false]
Call without arguments to see the current values.
To permanently change the value of an option add the corresponding
command to your ``~/.pdbrc`` file. If you are programmatically using the
Pdb instance you can also change the ``default_predicates`` class
attribute.
"""
if not args.strip():
print("current predicates:")
for p, v in self._predicates.items():
print(" ", p, ":", v)
return
type_value = args.strip().split(" ")
if len(type_value) != 2:
print(
f"Usage: skip_predicates <type> <value>, with <type> one of {set(self._predicates.keys())}"
)
return
type_, value = type_value
if type_ not in self._predicates:
print(f"{type_!r} not in {set(self._predicates.keys())}")
return
if value.lower() not in ("true", "yes", "1", "no", "false", "0"):
print(
f"{value!r} is invalid - use one of ('true', 'yes', '1', 'no', 'false', '0')"
)
return
self._predicates[type_] = value.lower() in ("true", "yes", "1")
if not any(self._predicates.values()):
print(
"Warning, all predicates set to False, skip_hidden may not have any effects."
)
def do_skip_hidden(self, arg):
"""
Change whether or not we should skip frames with the
__tracebackhide__ attribute.
"""
if not arg.strip():
print(
f"skip_hidden = {self.skip_hidden}, use 'yes','no', 'true', or 'false' to change."
)
elif arg.strip().lower() in ("true", "yes"):
self.skip_hidden = True
elif arg.strip().lower() in ("false", "no"):
self.skip_hidden = False
if not any(self._predicates.values()):
print(
"Warning, all predicates set to False, skip_hidden may not have any effects."
)
def do_list(self, arg):
"""Print lines of code from the current stack frame"""
self.lastcmd = "list"
last = None
if arg and arg != ".":
try:
x = eval(arg, {}, {})
if type(x) == type(()):
first, last = x
first = int(first)
last = int(last)
if last < first:
# Assume it's a count
last = first + last
else:
first = max(1, int(x) - 5)
except:
print("*** Error in argument:", repr(arg), file=self.stdout)
return
elif self.lineno is None or arg == ".":
assert self.curframe is not None
first = max(1, self.curframe.f_lineno - 5)
else:
first = self.lineno + 1
if last is None:
last = first + 10
assert self.curframe is not None
self.print_list_lines(self.curframe.f_code.co_filename, first, last)
lineno = first
filename = self.curframe.f_code.co_filename
self.shell.hooks.synchronize_with_editor(filename, lineno, 0)
do_l = do_list
def getsourcelines(self, obj):
lines, lineno = inspect.findsource(obj)
if inspect.isframe(obj) and obj.f_globals is self._get_frame_locals(obj):
# must be a module frame: do not try to cut a block out of it
return lines, 1
elif inspect.ismodule(obj):
return lines, 1
return inspect.getblock(lines[lineno:]), lineno + 1
def do_longlist(self, arg):
"""Print lines of code from the current stack frame.
Shows more lines than 'list' does.
"""
self.lastcmd = "longlist"
try:
lines, lineno = self.getsourcelines(self.curframe)
except OSError as err:
self.error(str(err))
return
last = lineno + len(lines)
assert self.curframe is not None
self.print_list_lines(self.curframe.f_code.co_filename, lineno, last)
do_ll = do_longlist
def do_debug(self, arg):
"""debug code
Enter a recursive debugger that steps through the code
argument (which is an arbitrary expression or statement to be
executed in the current environment).
"""
trace_function = sys.gettrace()
sys.settrace(None)
assert self.curframe is not None
globals = self.curframe.f_globals
locals = self.curframe_locals
p = self.__class__(
completekey=self.completekey, stdin=self.stdin, stdout=self.stdout
)
p.use_rawinput = self.use_rawinput
p.prompt = "(%s) " % self.prompt.strip()
self.message("ENTERING RECURSIVE DEBUGGER")
sys.call_tracing(p.run, (arg, globals, locals))
self.message("LEAVING RECURSIVE DEBUGGER")
sys.settrace(trace_function)
self.lastcmd = p.lastcmd
def do_pdef(self, arg):
"""Print the call signature for any callable object.
The debugger interface to %pdef"""
assert self.curframe is not None
namespaces = [
("Locals", self.curframe_locals),
("Globals", self.curframe.f_globals),
]
self.shell.find_line_magic("pdef")(arg, namespaces=namespaces)
def do_pdoc(self, arg):
"""Print the docstring for an object.
The debugger interface to %pdoc."""
assert self.curframe is not None
namespaces = [
("Locals", self.curframe_locals),
("Globals", self.curframe.f_globals),
]
self.shell.find_line_magic("pdoc")(arg, namespaces=namespaces)
def do_pfile(self, arg):
"""Print (or run through pager) the file where an object is defined.
The debugger interface to %pfile.
"""
assert self.curframe is not None
namespaces = [
("Locals", self.curframe_locals),
("Globals", self.curframe.f_globals),
]
self.shell.find_line_magic("pfile")(arg, namespaces=namespaces)
def do_pinfo(self, arg):
"""Provide detailed information about an object.
The debugger interface to %pinfo, i.e., obj?."""
assert self.curframe is not None
namespaces = [
("Locals", self.curframe_locals),
("Globals", self.curframe.f_globals),
]
self.shell.find_line_magic("pinfo")(arg, namespaces=namespaces)
def do_pinfo2(self, arg):
"""Provide extra detailed information about an object.
The debugger interface to %pinfo2, i.e., obj??."""
assert self.curframe is not None
namespaces = [
("Locals", self.curframe_locals),
("Globals", self.curframe.f_globals),
]
self.shell.find_line_magic("pinfo2")(arg, namespaces=namespaces)
def do_psource(self, arg):
"""Print (or run through pager) the source code for an object."""
assert self.curframe is not None
namespaces = [
("Locals", self.curframe_locals),
("Globals", self.curframe.f_globals),
]
self.shell.find_line_magic("psource")(arg, namespaces=namespaces)
def do_where(self, arg: str):
"""w(here)
Print a stack trace, with the most recent frame at the bottom.
An arrow indicates the "current frame", which determines the
context of most commands. 'bt' is an alias for this command.
Take a number as argument as an (optional) number of context line to
print"""
if arg:
try:
context = int(arg)
except ValueError as err:
self.error(str(err))
return
self.print_stack_trace(context)
else:
self.print_stack_trace()
do_w = do_where
def break_anywhere(self, frame):
"""
_stop_in_decorator_internals is overly restrictive, as we may still want
to trace function calls, so we need to also update break_anywhere so
that is we don't `stop_here`, because of debugger skip, we may still
stop at any point inside the function
"""
sup = super().break_anywhere(frame)
if sup:
return sup
if self._predicates["debuggerskip"]:
if DEBUGGERSKIP in frame.f_code.co_varnames:
return True
if frame.f_back and self._get_frame_locals(frame.f_back).get(DEBUGGERSKIP):
return True
return False
def _is_in_decorator_internal_and_should_skip(self, frame):
"""
Utility to tell us whether we are in a decorator internal and should stop.
"""
# if we are disabled don't skip
if not self._predicates["debuggerskip"]:
return False
return self._cachable_skip(frame)
@lru_cache(1024)
def _cached_one_parent_frame_debuggerskip(self, frame):
"""
Cache looking up for DEBUGGERSKIP on parent frame.
This should speedup walking through deep frame when one of the highest
one does have a debugger skip.
This is likely to introduce fake positive though.
"""
while getattr(frame, "f_back", None):
frame = frame.f_back
if self._get_frame_locals(frame).get(DEBUGGERSKIP):
return True
return None
@lru_cache(1024)
def _cachable_skip(self, frame):
# if frame is tagged, skip by default.
if DEBUGGERSKIP in frame.f_code.co_varnames:
return True
# if one of the parent frame value set to True skip as well.
if self._cached_one_parent_frame_debuggerskip(frame):
return True
return False
def stop_here(self, frame):
if self._is_in_decorator_internal_and_should_skip(frame) is True:
return False
hidden = False
if self.skip_hidden:
hidden = self._hidden_predicate(frame)
if hidden:
if self.report_skipped:
print(
self.theme.format(
[
(
Token.ExcName,
" [... skipped 1 hidden frame(s)]",
),
(Token, "\n"),
]
)
)
if self.skip and self.is_skipped_module(frame.f_globals.get("__name__", "")):
print(
self.theme.format(
[
(
Token.ExcName,
" [... skipped 1 ignored module(s)]",
),
(Token, "\n"),
]
)
)
return False
return super().stop_here(frame)
def do_up(self, arg):
"""u(p) [count]
Move the current frame count (default one) levels up in the
stack trace (to an older frame).
Will skip hidden frames and ignored modules.
"""
# modified version of upstream that skips
# frames with __tracebackhide__ and ignored modules
if self.curindex == 0:
self.error("Oldest frame")
return
try:
count = int(arg or 1)
except ValueError:
self.error("Invalid frame count (%s)" % arg)
return
hidden_skipped = 0
module_skipped = 0
if count < 0:
_newframe = 0
else:
counter = 0
hidden_frames = self.hidden_frames(self.stack)
for i in range(self.curindex - 1, -1, -1):
should_skip_hidden = hidden_frames[i] and self.skip_hidden
should_skip_module = self.skip and self.is_skipped_module(
self.stack[i][0].f_globals.get("__name__", "")
)
if should_skip_hidden or should_skip_module:
if should_skip_hidden:
hidden_skipped += 1
if should_skip_module:
module_skipped += 1
continue
counter += 1
if counter >= count:
break
else:
# if no break occurred.
self.error(
"all frames above skipped (hidden frames and ignored modules). Use `skip_hidden False` for hidden frames or unignore_module for ignored modules."
)
return
_newframe = i
self._select_frame(_newframe)
total_skipped = hidden_skipped + module_skipped
if total_skipped:
print(
self.theme.format(
[
(
Token.ExcName,
f" [... skipped {total_skipped} frame(s): {hidden_skipped} hidden frames + {module_skipped} ignored modules]",
),
(Token, "\n"),
]
)
)
def do_down(self, arg):
"""d(own) [count]
Move the current frame count (default one) levels down in the
stack trace (to a newer frame).
Will skip hidden frames and ignored modules.
"""
if self.curindex + 1 == len(self.stack):
self.error("Newest frame")
return
try:
count = int(arg or 1)
except ValueError:
self.error("Invalid frame count (%s)" % arg)
return
if count < 0:
_newframe = len(self.stack) - 1
else:
counter = 0
hidden_skipped = 0
module_skipped = 0
hidden_frames = self.hidden_frames(self.stack)
for i in range(self.curindex + 1, len(self.stack)):
should_skip_hidden = hidden_frames[i] and self.skip_hidden
should_skip_module = self.skip and self.is_skipped_module(
self.stack[i][0].f_globals.get("__name__", "")
)
if should_skip_hidden or should_skip_module:
if should_skip_hidden:
hidden_skipped += 1
if should_skip_module:
module_skipped += 1
continue
counter += 1
if counter >= count:
break
else:
self.error(
"all frames below skipped (hidden frames and ignored modules). Use `skip_hidden False` for hidden frames or unignore_module for ignored modules."
)
return
total_skipped = hidden_skipped + module_skipped
if total_skipped:
print(
self.theme.format(
[
(
Token.ExcName,
f" [... skipped {total_skipped} frame(s): {hidden_skipped} hidden frames + {module_skipped} ignored modules]",
),
(Token, "\n"),
]
)
)
_newframe = i
self._select_frame(_newframe)
do_d = do_down
do_u = do_up
def _show_ignored_modules(self):
"""Display currently ignored modules."""
if self.skip:
print(f"Currently ignored modules: {sorted(self.skip)}")
else:
print("No modules are currently ignored.")
def do_ignore_module(self, arg):
"""ignore_module <module_name>
Add a module to the list of modules to skip when navigating frames.
When a module is ignored, the debugger will automatically skip over
frames from that module.
Supports wildcard patterns using fnmatch syntax:
Usage:
ignore_module threading # Skip threading module frames
ignore_module asyncio.\\* # Skip all asyncio submodules
ignore_module \\*.tests # Skip all test modules
ignore_module # List currently ignored modules
"""
if self.skip is None:
self.skip = set()
module_name = arg.strip()
if not module_name:
self._show_ignored_modules()
return
self.skip.add(module_name)
def do_unignore_module(self, arg):
"""unignore_module <module_name>
Remove a module from the list of modules to skip when navigating frames.
This will allow the debugger to step into frames from the specified module.
Usage:
unignore_module threading # Stop ignoring threading module frames
unignore_module asyncio.\\* # Remove asyncio.* pattern
unignore_module # List currently ignored modules
"""
if self.skip is None:
self.skip = set()
module_name = arg.strip()
if not module_name:
self._show_ignored_modules()
return
try:
self.skip.remove(module_name)
except KeyError:
print(f"Module {module_name} is not currently ignored")
self._show_ignored_modules()
def do_context(self, context: str):
"""context number_of_lines
Set the number of lines of source code to show when displaying
stacktrace information.
"""
try:
new_context = int(context)
if new_context <= 0:
raise ValueError()
self.context = new_context
except ValueError:
self.error(
f"The 'context' command requires a positive integer argument (current value {self.context})."
)
class InterruptiblePdb(Pdb):
"""Version of debugger where KeyboardInterrupt exits the debugger altogether."""
def cmdloop(self, intro=None):
"""Wrap cmdloop() such that KeyboardInterrupt stops the debugger."""
try:
return OldPdb.cmdloop(self, intro=intro)
except KeyboardInterrupt:
self.stop_here = lambda frame: False # type: ignore[method-assign]
self.do_quit("")
sys.settrace(None)
self.quitting = False
raise
def _cmdloop(self):
while True:
try:
# keyboard interrupts allow for an easy way to cancel
# the current command, so allow them during interactive input
self.allow_kbdint = True
self.cmdloop()
self.allow_kbdint = False
break
except KeyboardInterrupt:
self.message("--KeyboardInterrupt--")
raise
[docs]
def set_trace(frame=None, header=None):
"""
Start debugging from `frame`.
If frame is not specified, debugging starts from caller's frame.
"""
pdb = Pdb()
if header is not None:
pdb.message(header)
pdb.set_trace(frame or sys._getframe().f_back)