mirror of
https://github.com/python/cpython
synced 2024-07-20 09:45:46 +00:00
1596 lines
63 KiB
Python
1596 lines
63 KiB
Python
"""Extract, format and print information about Python stack traces."""
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import os
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import io
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import collections.abc
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import itertools
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import linecache
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import sys
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import textwrap
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import warnings
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from contextlib import suppress
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__all__ = ['extract_stack', 'extract_tb', 'format_exception',
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'format_exception_only', 'format_list', 'format_stack',
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'format_tb', 'print_exc', 'format_exc', 'print_exception',
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'print_last', 'print_stack', 'print_tb', 'clear_frames',
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'FrameSummary', 'StackSummary', 'TracebackException',
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'walk_stack', 'walk_tb']
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#
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# Formatting and printing lists of traceback lines.
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#
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_COLORIZE = True
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def print_list(extracted_list, file=None):
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"""Print the list of tuples as returned by extract_tb() or
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extract_stack() as a formatted stack trace to the given file."""
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if file is None:
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file = sys.stderr
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for item in StackSummary.from_list(extracted_list).format():
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print(item, file=file, end="")
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def format_list(extracted_list):
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"""Format a list of tuples or FrameSummary objects for printing.
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Given a list of tuples or FrameSummary objects as returned by
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extract_tb() or extract_stack(), return a list of strings ready
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for printing.
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Each string in the resulting list corresponds to the item with the
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same index in the argument list. Each string ends in a newline;
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the strings may contain internal newlines as well, for those items
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whose source text line is not None.
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"""
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return StackSummary.from_list(extracted_list).format()
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#
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# Printing and Extracting Tracebacks.
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#
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def print_tb(tb, limit=None, file=None):
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"""Print up to 'limit' stack trace entries from the traceback 'tb'.
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If 'limit' is omitted or None, all entries are printed. If 'file'
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is omitted or None, the output goes to sys.stderr; otherwise
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'file' should be an open file or file-like object with a write()
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method.
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"""
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print_list(extract_tb(tb, limit=limit), file=file)
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def format_tb(tb, limit=None):
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"""A shorthand for 'format_list(extract_tb(tb, limit))'."""
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return extract_tb(tb, limit=limit).format()
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def extract_tb(tb, limit=None):
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"""
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Return a StackSummary object representing a list of
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pre-processed entries from traceback.
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This is useful for alternate formatting of stack traces. If
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'limit' is omitted or None, all entries are extracted. A
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pre-processed stack trace entry is a FrameSummary object
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containing attributes filename, lineno, name, and line
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representing the information that is usually printed for a stack
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trace. The line is a string with leading and trailing
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whitespace stripped; if the source is not available it is None.
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"""
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return StackSummary._extract_from_extended_frame_gen(
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_walk_tb_with_full_positions(tb), limit=limit)
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#
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# Exception formatting and output.
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#
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_cause_message = (
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"\nThe above exception was the direct cause "
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"of the following exception:\n\n")
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_context_message = (
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"\nDuring handling of the above exception, "
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"another exception occurred:\n\n")
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class _Sentinel:
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def __repr__(self):
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return "<implicit>"
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_sentinel = _Sentinel()
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def _parse_value_tb(exc, value, tb):
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if (value is _sentinel) != (tb is _sentinel):
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raise ValueError("Both or neither of value and tb must be given")
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if value is tb is _sentinel:
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if exc is not None:
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if isinstance(exc, BaseException):
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return exc, exc.__traceback__
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raise TypeError(f'Exception expected for value, '
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f'{type(exc).__name__} found')
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else:
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return None, None
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return value, tb
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def print_exception(exc, /, value=_sentinel, tb=_sentinel, limit=None, \
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file=None, chain=True, **kwargs):
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"""Print exception up to 'limit' stack trace entries from 'tb' to 'file'.
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This differs from print_tb() in the following ways: (1) if
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traceback is not None, it prints a header "Traceback (most recent
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call last):"; (2) it prints the exception type and value after the
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stack trace; (3) if type is SyntaxError and value has the
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appropriate format, it prints the line where the syntax error
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occurred with a caret on the next line indicating the approximate
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position of the error.
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"""
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colorize = kwargs.get("colorize", False)
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value, tb = _parse_value_tb(exc, value, tb)
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te = TracebackException(type(value), value, tb, limit=limit, compact=True)
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te.print(file=file, chain=chain, colorize=colorize)
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BUILTIN_EXCEPTION_LIMIT = object()
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def _can_colorize():
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if sys.platform == "win32":
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try:
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import nt
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if not nt._supports_virtual_terminal():
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return False
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except (ImportError, AttributeError):
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return False
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if os.environ.get("PYTHON_COLORS") == "0":
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return False
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if os.environ.get("PYTHON_COLORS") == "1":
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return True
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if "NO_COLOR" in os.environ:
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return False
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if not _COLORIZE:
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return False
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if "FORCE_COLOR" in os.environ:
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return True
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if os.environ.get("TERM") == "dumb":
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return False
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try:
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return os.isatty(sys.stderr.fileno())
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except io.UnsupportedOperation:
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return sys.stderr.isatty()
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def _print_exception_bltin(exc, /):
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file = sys.stderr if sys.stderr is not None else sys.__stderr__
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colorize = _can_colorize()
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return print_exception(exc, limit=BUILTIN_EXCEPTION_LIMIT, file=file, colorize=colorize)
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def format_exception(exc, /, value=_sentinel, tb=_sentinel, limit=None, \
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chain=True):
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"""Format a stack trace and the exception information.
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The arguments have the same meaning as the corresponding arguments
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to print_exception(). The return value is a list of strings, each
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ending in a newline and some containing internal newlines. When
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these lines are concatenated and printed, exactly the same text is
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printed as does print_exception().
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"""
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value, tb = _parse_value_tb(exc, value, tb)
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te = TracebackException(type(value), value, tb, limit=limit, compact=True)
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return list(te.format(chain=chain))
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def format_exception_only(exc, /, value=_sentinel, *, show_group=False):
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"""Format the exception part of a traceback.
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The return value is a list of strings, each ending in a newline.
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The list contains the exception's message, which is
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normally a single string; however, for :exc:`SyntaxError` exceptions, it
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contains several lines that (when printed) display detailed information
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about where the syntax error occurred. Following the message, the list
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contains the exception's ``__notes__``.
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When *show_group* is ``True``, and the exception is an instance of
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:exc:`BaseExceptionGroup`, the nested exceptions are included as
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well, recursively, with indentation relative to their nesting depth.
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"""
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if value is _sentinel:
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value = exc
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te = TracebackException(type(value), value, None, compact=True)
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return list(te.format_exception_only(show_group=show_group))
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# -- not official API but folk probably use these two functions.
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def _format_final_exc_line(etype, value, *, insert_final_newline=True, colorize=False):
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valuestr = _safe_string(value, 'exception')
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end_char = "\n" if insert_final_newline else ""
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if colorize:
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if value is None or not valuestr:
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line = f"{_ANSIColors.BOLD_MAGENTA}{etype}{_ANSIColors.RESET}{end_char}"
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else:
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line = f"{_ANSIColors.BOLD_MAGENTA}{etype}{_ANSIColors.RESET}: {_ANSIColors.MAGENTA}{valuestr}{_ANSIColors.RESET}{end_char}"
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else:
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if value is None or not valuestr:
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line = f"{etype}{end_char}"
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else:
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line = f"{etype}: {valuestr}{end_char}"
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return line
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def _safe_string(value, what, func=str):
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try:
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return func(value)
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except:
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return f'<{what} {func.__name__}() failed>'
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# --
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def print_exc(limit=None, file=None, chain=True):
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"""Shorthand for 'print_exception(sys.exception(), limit, file, chain)'."""
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print_exception(sys.exception(), limit=limit, file=file, chain=chain)
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def format_exc(limit=None, chain=True):
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"""Like print_exc() but return a string."""
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return "".join(format_exception(sys.exception(), limit=limit, chain=chain))
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def print_last(limit=None, file=None, chain=True):
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"""This is a shorthand for 'print_exception(sys.last_exc, limit, file, chain)'."""
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if not hasattr(sys, "last_exc") and not hasattr(sys, "last_type"):
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raise ValueError("no last exception")
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if hasattr(sys, "last_exc"):
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print_exception(sys.last_exc, limit, file, chain)
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else:
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print_exception(sys.last_type, sys.last_value, sys.last_traceback,
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limit, file, chain)
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#
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# Printing and Extracting Stacks.
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#
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def print_stack(f=None, limit=None, file=None):
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"""Print a stack trace from its invocation point.
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The optional 'f' argument can be used to specify an alternate
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stack frame at which to start. The optional 'limit' and 'file'
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arguments have the same meaning as for print_exception().
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"""
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if f is None:
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f = sys._getframe().f_back
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print_list(extract_stack(f, limit=limit), file=file)
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def format_stack(f=None, limit=None):
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"""Shorthand for 'format_list(extract_stack(f, limit))'."""
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if f is None:
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f = sys._getframe().f_back
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return format_list(extract_stack(f, limit=limit))
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def extract_stack(f=None, limit=None):
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"""Extract the raw traceback from the current stack frame.
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The return value has the same format as for extract_tb(). The
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optional 'f' and 'limit' arguments have the same meaning as for
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print_stack(). Each item in the list is a quadruple (filename,
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line number, function name, text), and the entries are in order
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from oldest to newest stack frame.
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"""
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if f is None:
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f = sys._getframe().f_back
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stack = StackSummary.extract(walk_stack(f), limit=limit)
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stack.reverse()
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return stack
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def clear_frames(tb):
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"Clear all references to local variables in the frames of a traceback."
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while tb is not None:
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try:
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tb.tb_frame.clear()
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except RuntimeError:
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# Ignore the exception raised if the frame is still executing.
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pass
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tb = tb.tb_next
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class FrameSummary:
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"""Information about a single frame from a traceback.
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- :attr:`filename` The filename for the frame.
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- :attr:`lineno` The line within filename for the frame that was
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active when the frame was captured.
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- :attr:`name` The name of the function or method that was executing
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when the frame was captured.
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- :attr:`line` The text from the linecache module for the
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of code that was running when the frame was captured.
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- :attr:`locals` Either None if locals were not supplied, or a dict
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mapping the name to the repr() of the variable.
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"""
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__slots__ = ('filename', 'lineno', 'end_lineno', 'colno', 'end_colno',
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'name', '_lines', '_lines_dedented', 'locals')
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def __init__(self, filename, lineno, name, *, lookup_line=True,
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locals=None, line=None,
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end_lineno=None, colno=None, end_colno=None):
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"""Construct a FrameSummary.
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:param lookup_line: If True, `linecache` is consulted for the source
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code line. Otherwise, the line will be looked up when first needed.
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:param locals: If supplied the frame locals, which will be captured as
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object representations.
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:param line: If provided, use this instead of looking up the line in
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the linecache.
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"""
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self.filename = filename
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self.lineno = lineno
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self.end_lineno = lineno if end_lineno is None else end_lineno
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self.colno = colno
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self.end_colno = end_colno
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self.name = name
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self._lines = line
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self._lines_dedented = None
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if lookup_line:
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self.line
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self.locals = {k: _safe_string(v, 'local', func=repr)
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for k, v in locals.items()} if locals else None
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def __eq__(self, other):
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if isinstance(other, FrameSummary):
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return (self.filename == other.filename and
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self.lineno == other.lineno and
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self.name == other.name and
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self.locals == other.locals)
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if isinstance(other, tuple):
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return (self.filename, self.lineno, self.name, self.line) == other
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return NotImplemented
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def __getitem__(self, pos):
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return (self.filename, self.lineno, self.name, self.line)[pos]
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def __iter__(self):
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return iter([self.filename, self.lineno, self.name, self.line])
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def __repr__(self):
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return "<FrameSummary file {filename}, line {lineno} in {name}>".format(
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filename=self.filename, lineno=self.lineno, name=self.name)
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def __len__(self):
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return 4
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def _set_lines(self):
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if (
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self._lines is None
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and self.lineno is not None
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and self.end_lineno is not None
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):
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lines = []
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for lineno in range(self.lineno, self.end_lineno + 1):
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# treat errors (empty string) and empty lines (newline) as the same
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lines.append(linecache.getline(self.filename, lineno).rstrip())
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self._lines = "\n".join(lines) + "\n"
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@property
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def _original_lines(self):
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# Returns the line as-is from the source, without modifying whitespace.
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self._set_lines()
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return self._lines
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@property
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def _dedented_lines(self):
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# Returns _original_lines, but dedented
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self._set_lines()
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if self._lines_dedented is None and self._lines is not None:
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self._lines_dedented = textwrap.dedent(self._lines)
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return self._lines_dedented
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@property
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def line(self):
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self._set_lines()
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if self._lines is None:
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return None
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# return only the first line, stripped
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return self._lines.partition("\n")[0].strip()
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def walk_stack(f):
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"""Walk a stack yielding the frame and line number for each frame.
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This will follow f.f_back from the given frame. If no frame is given, the
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current stack is used. Usually used with StackSummary.extract.
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"""
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if f is None:
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f = sys._getframe().f_back.f_back.f_back.f_back
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while f is not None:
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yield f, f.f_lineno
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f = f.f_back
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def walk_tb(tb):
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"""Walk a traceback yielding the frame and line number for each frame.
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This will follow tb.tb_next (and thus is in the opposite order to
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walk_stack). Usually used with StackSummary.extract.
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"""
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while tb is not None:
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yield tb.tb_frame, tb.tb_lineno
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tb = tb.tb_next
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def _walk_tb_with_full_positions(tb):
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# Internal version of walk_tb that yields full code positions including
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# end line and column information.
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while tb is not None:
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positions = _get_code_position(tb.tb_frame.f_code, tb.tb_lasti)
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# Yield tb_lineno when co_positions does not have a line number to
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# maintain behavior with walk_tb.
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if positions[0] is None:
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yield tb.tb_frame, (tb.tb_lineno, ) + positions[1:]
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else:
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yield tb.tb_frame, positions
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tb = tb.tb_next
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def _get_code_position(code, instruction_index):
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if instruction_index < 0:
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return (None, None, None, None)
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positions_gen = code.co_positions()
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return next(itertools.islice(positions_gen, instruction_index // 2, None))
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_RECURSIVE_CUTOFF = 3 # Also hardcoded in traceback.c.
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class _ANSIColors:
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RED = '\x1b[31m'
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BOLD_RED = '\x1b[1;31m'
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MAGENTA = '\x1b[35m'
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BOLD_MAGENTA = '\x1b[1;35m'
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GREY = '\x1b[90m'
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RESET = '\x1b[0m'
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class StackSummary(list):
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"""A list of FrameSummary objects, representing a stack of frames."""
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@classmethod
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def extract(klass, frame_gen, *, limit=None, lookup_lines=True,
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capture_locals=False):
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"""Create a StackSummary from a traceback or stack object.
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:param frame_gen: A generator that yields (frame, lineno) tuples
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whose summaries are to be included in the stack.
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:param limit: None to include all frames or the number of frames to
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include.
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:param lookup_lines: If True, lookup lines for each frame immediately,
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otherwise lookup is deferred until the frame is rendered.
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:param capture_locals: If True, the local variables from each frame will
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be captured as object representations into the FrameSummary.
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"""
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def extended_frame_gen():
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for f, lineno in frame_gen:
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yield f, (lineno, None, None, None)
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return klass._extract_from_extended_frame_gen(
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extended_frame_gen(), limit=limit, lookup_lines=lookup_lines,
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capture_locals=capture_locals)
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@classmethod
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def _extract_from_extended_frame_gen(klass, frame_gen, *, limit=None,
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lookup_lines=True, capture_locals=False):
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# Same as extract but operates on a frame generator that yields
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# (frame, (lineno, end_lineno, colno, end_colno)) in the stack.
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# Only lineno is required, the remaining fields can be None if the
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# information is not available.
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builtin_limit = limit is BUILTIN_EXCEPTION_LIMIT
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if limit is None or builtin_limit:
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limit = getattr(sys, 'tracebacklimit', None)
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if limit is not None and limit < 0:
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limit = 0
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if limit is not None:
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if builtin_limit:
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frame_gen = tuple(frame_gen)
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frame_gen = frame_gen[len(frame_gen) - limit:]
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elif limit >= 0:
|
|
frame_gen = itertools.islice(frame_gen, limit)
|
|
else:
|
|
frame_gen = collections.deque(frame_gen, maxlen=-limit)
|
|
|
|
result = klass()
|
|
fnames = set()
|
|
for f, (lineno, end_lineno, colno, end_colno) in frame_gen:
|
|
co = f.f_code
|
|
filename = co.co_filename
|
|
name = co.co_name
|
|
fnames.add(filename)
|
|
linecache.lazycache(filename, f.f_globals)
|
|
# Must defer line lookups until we have called checkcache.
|
|
if capture_locals:
|
|
f_locals = f.f_locals
|
|
else:
|
|
f_locals = None
|
|
result.append(FrameSummary(
|
|
filename, lineno, name, lookup_line=False, locals=f_locals,
|
|
end_lineno=end_lineno, colno=colno, end_colno=end_colno))
|
|
for filename in fnames:
|
|
linecache.checkcache(filename)
|
|
|
|
# If immediate lookup was desired, trigger lookups now.
|
|
if lookup_lines:
|
|
for f in result:
|
|
f.line
|
|
return result
|
|
|
|
@classmethod
|
|
def from_list(klass, a_list):
|
|
"""
|
|
Create a StackSummary object from a supplied list of
|
|
FrameSummary objects or old-style list of tuples.
|
|
"""
|
|
# While doing a fast-path check for isinstance(a_list, StackSummary) is
|
|
# appealing, idlelib.run.cleanup_traceback and other similar code may
|
|
# break this by making arbitrary frames plain tuples, so we need to
|
|
# check on a frame by frame basis.
|
|
result = StackSummary()
|
|
for frame in a_list:
|
|
if isinstance(frame, FrameSummary):
|
|
result.append(frame)
|
|
else:
|
|
filename, lineno, name, line = frame
|
|
result.append(FrameSummary(filename, lineno, name, line=line))
|
|
return result
|
|
|
|
def format_frame_summary(self, frame_summary, **kwargs):
|
|
"""Format the lines for a single FrameSummary.
|
|
|
|
Returns a string representing one frame involved in the stack. This
|
|
gets called for every frame to be printed in the stack summary.
|
|
"""
|
|
colorize = kwargs.get("colorize", False)
|
|
row = []
|
|
filename = frame_summary.filename
|
|
if frame_summary.filename.startswith("<stdin>-"):
|
|
filename = "<stdin>"
|
|
if colorize:
|
|
row.append(' File {}"{}"{}, line {}{}{}, in {}{}{}\n'.format(
|
|
_ANSIColors.MAGENTA,
|
|
filename,
|
|
_ANSIColors.RESET,
|
|
_ANSIColors.MAGENTA,
|
|
frame_summary.lineno,
|
|
_ANSIColors.RESET,
|
|
_ANSIColors.MAGENTA,
|
|
frame_summary.name,
|
|
_ANSIColors.RESET,
|
|
)
|
|
)
|
|
else:
|
|
row.append(' File "{}", line {}, in {}\n'.format(
|
|
filename, frame_summary.lineno, frame_summary.name))
|
|
if frame_summary._dedented_lines and frame_summary._dedented_lines.strip():
|
|
if (
|
|
frame_summary.colno is None or
|
|
frame_summary.end_colno is None
|
|
):
|
|
# only output first line if column information is missing
|
|
row.append(textwrap.indent(frame_summary.line, ' ') + "\n")
|
|
else:
|
|
# get first and last line
|
|
all_lines_original = frame_summary._original_lines.splitlines()
|
|
first_line = all_lines_original[0]
|
|
# assume all_lines_original has enough lines (since we constructed it)
|
|
last_line = all_lines_original[frame_summary.end_lineno - frame_summary.lineno]
|
|
|
|
# character index of the start/end of the instruction
|
|
start_offset = _byte_offset_to_character_offset(first_line, frame_summary.colno)
|
|
end_offset = _byte_offset_to_character_offset(last_line, frame_summary.end_colno)
|
|
|
|
all_lines = frame_summary._dedented_lines.splitlines()[
|
|
:frame_summary.end_lineno - frame_summary.lineno + 1
|
|
]
|
|
|
|
# adjust start/end offset based on dedent
|
|
dedent_characters = len(first_line) - len(all_lines[0])
|
|
start_offset = max(0, start_offset - dedent_characters)
|
|
end_offset = max(0, end_offset - dedent_characters)
|
|
|
|
# When showing this on a terminal, some of the non-ASCII characters
|
|
# might be rendered as double-width characters, so we need to take
|
|
# that into account when calculating the length of the line.
|
|
dp_start_offset = _display_width(all_lines[0], offset=start_offset)
|
|
dp_end_offset = _display_width(all_lines[-1], offset=end_offset)
|
|
|
|
# get exact code segment corresponding to the instruction
|
|
segment = "\n".join(all_lines)
|
|
segment = segment[start_offset:len(segment) - (len(all_lines[-1]) - end_offset)]
|
|
|
|
# attempt to parse for anchors
|
|
anchors = None
|
|
with suppress(Exception):
|
|
anchors = _extract_caret_anchors_from_line_segment(segment)
|
|
|
|
# only use carets if there are anchors or the carets do not span all lines
|
|
show_carets = False
|
|
if anchors or all_lines[0][:start_offset].lstrip() or all_lines[-1][end_offset:].rstrip():
|
|
show_carets = True
|
|
|
|
result = []
|
|
|
|
# only display first line, last line, and lines around anchor start/end
|
|
significant_lines = {0, len(all_lines) - 1}
|
|
|
|
anchors_left_end_offset = 0
|
|
anchors_right_start_offset = 0
|
|
primary_char = "^"
|
|
secondary_char = "^"
|
|
if anchors:
|
|
anchors_left_end_offset = anchors.left_end_offset
|
|
anchors_right_start_offset = anchors.right_start_offset
|
|
# computed anchor positions do not take start_offset into account,
|
|
# so account for it here
|
|
if anchors.left_end_lineno == 0:
|
|
anchors_left_end_offset += start_offset
|
|
if anchors.right_start_lineno == 0:
|
|
anchors_right_start_offset += start_offset
|
|
|
|
# account for display width
|
|
anchors_left_end_offset = _display_width(
|
|
all_lines[anchors.left_end_lineno], offset=anchors_left_end_offset
|
|
)
|
|
anchors_right_start_offset = _display_width(
|
|
all_lines[anchors.right_start_lineno], offset=anchors_right_start_offset
|
|
)
|
|
|
|
primary_char = anchors.primary_char
|
|
secondary_char = anchors.secondary_char
|
|
significant_lines.update(
|
|
range(anchors.left_end_lineno - 1, anchors.left_end_lineno + 2)
|
|
)
|
|
significant_lines.update(
|
|
range(anchors.right_start_lineno - 1, anchors.right_start_lineno + 2)
|
|
)
|
|
|
|
# remove bad line numbers
|
|
significant_lines.discard(-1)
|
|
significant_lines.discard(len(all_lines))
|
|
|
|
def output_line(lineno):
|
|
"""output all_lines[lineno] along with carets"""
|
|
result.append(all_lines[lineno] + "\n")
|
|
if not show_carets:
|
|
return
|
|
num_spaces = len(all_lines[lineno]) - len(all_lines[lineno].lstrip())
|
|
carets = []
|
|
num_carets = dp_end_offset if lineno == len(all_lines) - 1 else _display_width(all_lines[lineno])
|
|
# compute caret character for each position
|
|
for col in range(num_carets):
|
|
if col < num_spaces or (lineno == 0 and col < dp_start_offset):
|
|
# before first non-ws char of the line, or before start of instruction
|
|
carets.append(' ')
|
|
elif anchors and (
|
|
lineno > anchors.left_end_lineno or
|
|
(lineno == anchors.left_end_lineno and col >= anchors_left_end_offset)
|
|
) and (
|
|
lineno < anchors.right_start_lineno or
|
|
(lineno == anchors.right_start_lineno and col < anchors_right_start_offset)
|
|
):
|
|
# within anchors
|
|
carets.append(secondary_char)
|
|
else:
|
|
carets.append(primary_char)
|
|
if colorize:
|
|
# Replace the previous line with a red version of it only in the parts covered
|
|
# by the carets.
|
|
line = result[-1]
|
|
colorized_line_parts = []
|
|
colorized_carets_parts = []
|
|
|
|
for color, group in itertools.groupby(itertools.zip_longest(line, carets, fillvalue=""), key=lambda x: x[1]):
|
|
caret_group = list(group)
|
|
if color == "^":
|
|
colorized_line_parts.append(_ANSIColors.BOLD_RED + "".join(char for char, _ in caret_group) + _ANSIColors.RESET)
|
|
colorized_carets_parts.append(_ANSIColors.BOLD_RED + "".join(caret for _, caret in caret_group) + _ANSIColors.RESET)
|
|
elif color == "~":
|
|
colorized_line_parts.append(_ANSIColors.RED + "".join(char for char, _ in caret_group) + _ANSIColors.RESET)
|
|
colorized_carets_parts.append(_ANSIColors.RED + "".join(caret for _, caret in caret_group) + _ANSIColors.RESET)
|
|
else:
|
|
colorized_line_parts.append("".join(char for char, _ in caret_group))
|
|
colorized_carets_parts.append("".join(caret for _, caret in caret_group))
|
|
|
|
colorized_line = "".join(colorized_line_parts)
|
|
colorized_carets = "".join(colorized_carets_parts)
|
|
result[-1] = colorized_line
|
|
result.append(colorized_carets + "\n")
|
|
else:
|
|
result.append("".join(carets) + "\n")
|
|
|
|
# display significant lines
|
|
sig_lines_list = sorted(significant_lines)
|
|
for i, lineno in enumerate(sig_lines_list):
|
|
if i:
|
|
linediff = lineno - sig_lines_list[i - 1]
|
|
if linediff == 2:
|
|
# 1 line in between - just output it
|
|
output_line(lineno - 1)
|
|
elif linediff > 2:
|
|
# > 1 line in between - abbreviate
|
|
result.append(f"...<{linediff - 1} lines>...\n")
|
|
output_line(lineno)
|
|
|
|
row.append(
|
|
textwrap.indent(textwrap.dedent("".join(result)), ' ', lambda line: True)
|
|
)
|
|
if frame_summary.locals:
|
|
for name, value in sorted(frame_summary.locals.items()):
|
|
row.append(' {name} = {value}\n'.format(name=name, value=value))
|
|
|
|
return ''.join(row)
|
|
|
|
def format(self, **kwargs):
|
|
"""Format the stack ready for printing.
|
|
|
|
Returns a list of strings ready for printing. Each string in the
|
|
resulting list corresponds to a single frame from the stack.
|
|
Each string ends in a newline; the strings may contain internal
|
|
newlines as well, for those items with source text lines.
|
|
|
|
For long sequences of the same frame and line, the first few
|
|
repetitions are shown, followed by a summary line stating the exact
|
|
number of further repetitions.
|
|
"""
|
|
colorize = kwargs.get("colorize", False)
|
|
result = []
|
|
last_file = None
|
|
last_line = None
|
|
last_name = None
|
|
count = 0
|
|
for frame_summary in self:
|
|
formatted_frame = self.format_frame_summary(frame_summary, colorize=colorize)
|
|
if formatted_frame is None:
|
|
continue
|
|
if (last_file is None or last_file != frame_summary.filename or
|
|
last_line is None or last_line != frame_summary.lineno or
|
|
last_name is None or last_name != frame_summary.name):
|
|
if count > _RECURSIVE_CUTOFF:
|
|
count -= _RECURSIVE_CUTOFF
|
|
result.append(
|
|
f' [Previous line repeated {count} more '
|
|
f'time{"s" if count > 1 else ""}]\n'
|
|
)
|
|
last_file = frame_summary.filename
|
|
last_line = frame_summary.lineno
|
|
last_name = frame_summary.name
|
|
count = 0
|
|
count += 1
|
|
if count > _RECURSIVE_CUTOFF:
|
|
continue
|
|
result.append(formatted_frame)
|
|
|
|
if count > _RECURSIVE_CUTOFF:
|
|
count -= _RECURSIVE_CUTOFF
|
|
result.append(
|
|
f' [Previous line repeated {count} more '
|
|
f'time{"s" if count > 1 else ""}]\n'
|
|
)
|
|
return result
|
|
|
|
|
|
def _byte_offset_to_character_offset(str, offset):
|
|
as_utf8 = str.encode('utf-8')
|
|
return len(as_utf8[:offset].decode("utf-8", errors="replace"))
|
|
|
|
|
|
_Anchors = collections.namedtuple(
|
|
"_Anchors",
|
|
[
|
|
"left_end_lineno",
|
|
"left_end_offset",
|
|
"right_start_lineno",
|
|
"right_start_offset",
|
|
"primary_char",
|
|
"secondary_char",
|
|
],
|
|
defaults=["~", "^"]
|
|
)
|
|
|
|
def _extract_caret_anchors_from_line_segment(segment):
|
|
"""
|
|
Given source code `segment` corresponding to a FrameSummary, determine:
|
|
- for binary ops, the location of the binary op
|
|
- for indexing and function calls, the location of the brackets.
|
|
`segment` is expected to be a valid Python expression.
|
|
"""
|
|
import ast
|
|
|
|
try:
|
|
# Without parentheses, `segment` is parsed as a statement.
|
|
# Binary ops, subscripts, and calls are expressions, so
|
|
# we can wrap them with parentheses to parse them as
|
|
# (possibly multi-line) expressions.
|
|
# e.g. if we try to highlight the addition in
|
|
# x = (
|
|
# a +
|
|
# b
|
|
# )
|
|
# then we would ast.parse
|
|
# a +
|
|
# b
|
|
# which is not a valid statement because of the newline.
|
|
# Adding brackets makes it a valid expression.
|
|
# (
|
|
# a +
|
|
# b
|
|
# )
|
|
# Line locations will be different than the original,
|
|
# which is taken into account later on.
|
|
tree = ast.parse(f"(\n{segment}\n)")
|
|
except SyntaxError:
|
|
return None
|
|
|
|
if len(tree.body) != 1:
|
|
return None
|
|
|
|
lines = segment.splitlines()
|
|
|
|
def normalize(lineno, offset):
|
|
"""Get character index given byte offset"""
|
|
return _byte_offset_to_character_offset(lines[lineno], offset)
|
|
|
|
def next_valid_char(lineno, col):
|
|
"""Gets the next valid character index in `lines`, if
|
|
the current location is not valid. Handles empty lines.
|
|
"""
|
|
while lineno < len(lines) and col >= len(lines[lineno]):
|
|
col = 0
|
|
lineno += 1
|
|
assert lineno < len(lines) and col < len(lines[lineno])
|
|
return lineno, col
|
|
|
|
def increment(lineno, col):
|
|
"""Get the next valid character index in `lines`."""
|
|
col += 1
|
|
lineno, col = next_valid_char(lineno, col)
|
|
return lineno, col
|
|
|
|
def nextline(lineno, col):
|
|
"""Get the next valid character at least on the next line"""
|
|
col = 0
|
|
lineno += 1
|
|
lineno, col = next_valid_char(lineno, col)
|
|
return lineno, col
|
|
|
|
def increment_until(lineno, col, stop):
|
|
"""Get the next valid non-"\\#" character that satisfies the `stop` predicate"""
|
|
while True:
|
|
ch = lines[lineno][col]
|
|
if ch in "\\#":
|
|
lineno, col = nextline(lineno, col)
|
|
elif not stop(ch):
|
|
lineno, col = increment(lineno, col)
|
|
else:
|
|
break
|
|
return lineno, col
|
|
|
|
def setup_positions(expr, force_valid=True):
|
|
"""Get the lineno/col position of the end of `expr`. If `force_valid` is True,
|
|
forces the position to be a valid character (e.g. if the position is beyond the
|
|
end of the line, move to the next line)
|
|
"""
|
|
# -2 since end_lineno is 1-indexed and because we added an extra
|
|
# bracket + newline to `segment` when calling ast.parse
|
|
lineno = expr.end_lineno - 2
|
|
col = normalize(lineno, expr.end_col_offset)
|
|
return next_valid_char(lineno, col) if force_valid else (lineno, col)
|
|
|
|
statement = tree.body[0]
|
|
match statement:
|
|
case ast.Expr(expr):
|
|
match expr:
|
|
case ast.BinOp():
|
|
# ast gives these locations for BinOp subexpressions
|
|
# ( left_expr ) + ( right_expr )
|
|
# left^^^^^ right^^^^^
|
|
lineno, col = setup_positions(expr.left)
|
|
|
|
# First operator character is the first non-space/')' character
|
|
lineno, col = increment_until(lineno, col, lambda x: not x.isspace() and x != ')')
|
|
|
|
# binary op is 1 or 2 characters long, on the same line,
|
|
# before the right subexpression
|
|
right_col = col + 1
|
|
if (
|
|
right_col < len(lines[lineno])
|
|
and (
|
|
# operator char should not be in the right subexpression
|
|
expr.right.lineno - 2 > lineno or
|
|
right_col < normalize(expr.right.lineno - 2, expr.right.col_offset)
|
|
)
|
|
and not (ch := lines[lineno][right_col]).isspace()
|
|
and ch not in "\\#"
|
|
):
|
|
right_col += 1
|
|
|
|
# right_col can be invalid since it is exclusive
|
|
return _Anchors(lineno, col, lineno, right_col)
|
|
case ast.Subscript():
|
|
# ast gives these locations for value and slice subexpressions
|
|
# ( value_expr ) [ slice_expr ]
|
|
# value^^^^^ slice^^^^^
|
|
# subscript^^^^^^^^^^^^^^^^^^^^
|
|
|
|
# find left bracket
|
|
left_lineno, left_col = setup_positions(expr.value)
|
|
left_lineno, left_col = increment_until(left_lineno, left_col, lambda x: x == '[')
|
|
# find right bracket (final character of expression)
|
|
right_lineno, right_col = setup_positions(expr, force_valid=False)
|
|
return _Anchors(left_lineno, left_col, right_lineno, right_col)
|
|
case ast.Call():
|
|
# ast gives these locations for function call expressions
|
|
# ( func_expr ) (args, kwargs)
|
|
# func^^^^^
|
|
# call^^^^^^^^^^^^^^^^^^^^^^^^
|
|
|
|
# find left bracket
|
|
left_lineno, left_col = setup_positions(expr.func)
|
|
left_lineno, left_col = increment_until(left_lineno, left_col, lambda x: x == '(')
|
|
# find right bracket (final character of expression)
|
|
right_lineno, right_col = setup_positions(expr, force_valid=False)
|
|
return _Anchors(left_lineno, left_col, right_lineno, right_col)
|
|
|
|
return None
|
|
|
|
_WIDE_CHAR_SPECIFIERS = "WF"
|
|
|
|
def _display_width(line, offset=None):
|
|
"""Calculate the extra amount of width space the given source
|
|
code segment might take if it were to be displayed on a fixed
|
|
width output device. Supports wide unicode characters and emojis."""
|
|
|
|
if offset is None:
|
|
offset = len(line)
|
|
|
|
# Fast track for ASCII-only strings
|
|
if line.isascii():
|
|
return offset
|
|
|
|
import unicodedata
|
|
|
|
return sum(
|
|
2 if unicodedata.east_asian_width(char) in _WIDE_CHAR_SPECIFIERS else 1
|
|
for char in line[:offset]
|
|
)
|
|
|
|
|
|
|
|
class _ExceptionPrintContext:
|
|
def __init__(self):
|
|
self.seen = set()
|
|
self.exception_group_depth = 0
|
|
self.need_close = False
|
|
|
|
def indent(self):
|
|
return ' ' * (2 * self.exception_group_depth)
|
|
|
|
def emit(self, text_gen, margin_char=None):
|
|
if margin_char is None:
|
|
margin_char = '|'
|
|
indent_str = self.indent()
|
|
if self.exception_group_depth:
|
|
indent_str += margin_char + ' '
|
|
|
|
if isinstance(text_gen, str):
|
|
yield textwrap.indent(text_gen, indent_str, lambda line: True)
|
|
else:
|
|
for text in text_gen:
|
|
yield textwrap.indent(text, indent_str, lambda line: True)
|
|
|
|
|
|
class TracebackException:
|
|
"""An exception ready for rendering.
|
|
|
|
The traceback module captures enough attributes from the original exception
|
|
to this intermediary form to ensure that no references are held, while
|
|
still being able to fully print or format it.
|
|
|
|
max_group_width and max_group_depth control the formatting of exception
|
|
groups. The depth refers to the nesting level of the group, and the width
|
|
refers to the size of a single exception group's exceptions array. The
|
|
formatted output is truncated when either limit is exceeded.
|
|
|
|
Use `from_exception` to create TracebackException instances from exception
|
|
objects, or the constructor to create TracebackException instances from
|
|
individual components.
|
|
|
|
- :attr:`__cause__` A TracebackException of the original *__cause__*.
|
|
- :attr:`__context__` A TracebackException of the original *__context__*.
|
|
- :attr:`exceptions` For exception groups - a list of TracebackException
|
|
instances for the nested *exceptions*. ``None`` for other exceptions.
|
|
- :attr:`__suppress_context__` The *__suppress_context__* value from the
|
|
original exception.
|
|
- :attr:`stack` A `StackSummary` representing the traceback.
|
|
- :attr:`exc_type` (deprecated) The class of the original traceback.
|
|
- :attr:`exc_type_str` String display of exc_type
|
|
- :attr:`filename` For syntax errors - the filename where the error
|
|
occurred.
|
|
- :attr:`lineno` For syntax errors - the linenumber where the error
|
|
occurred.
|
|
- :attr:`end_lineno` For syntax errors - the end linenumber where the error
|
|
occurred. Can be `None` if not present.
|
|
- :attr:`text` For syntax errors - the text where the error
|
|
occurred.
|
|
- :attr:`offset` For syntax errors - the offset into the text where the
|
|
error occurred.
|
|
- :attr:`end_offset` For syntax errors - the end offset into the text where
|
|
the error occurred. Can be `None` if not present.
|
|
- :attr:`msg` For syntax errors - the compiler error message.
|
|
"""
|
|
|
|
def __init__(self, exc_type, exc_value, exc_traceback, *, limit=None,
|
|
lookup_lines=True, capture_locals=False, compact=False,
|
|
max_group_width=15, max_group_depth=10, save_exc_type=True, _seen=None):
|
|
# NB: we need to accept exc_traceback, exc_value, exc_traceback to
|
|
# permit backwards compat with the existing API, otherwise we
|
|
# need stub thunk objects just to glue it together.
|
|
# Handle loops in __cause__ or __context__.
|
|
is_recursive_call = _seen is not None
|
|
if _seen is None:
|
|
_seen = set()
|
|
_seen.add(id(exc_value))
|
|
|
|
self.max_group_width = max_group_width
|
|
self.max_group_depth = max_group_depth
|
|
|
|
self.stack = StackSummary._extract_from_extended_frame_gen(
|
|
_walk_tb_with_full_positions(exc_traceback),
|
|
limit=limit, lookup_lines=lookup_lines,
|
|
capture_locals=capture_locals)
|
|
|
|
self._exc_type = exc_type if save_exc_type else None
|
|
|
|
# Capture now to permit freeing resources: only complication is in the
|
|
# unofficial API _format_final_exc_line
|
|
self._str = _safe_string(exc_value, 'exception')
|
|
try:
|
|
self.__notes__ = getattr(exc_value, '__notes__', None)
|
|
except Exception as e:
|
|
self.__notes__ = [
|
|
f'Ignored error getting __notes__: {_safe_string(e, '__notes__', repr)}']
|
|
|
|
self._is_syntax_error = False
|
|
self._have_exc_type = exc_type is not None
|
|
if exc_type is not None:
|
|
self.exc_type_qualname = exc_type.__qualname__
|
|
self.exc_type_module = exc_type.__module__
|
|
else:
|
|
self.exc_type_qualname = None
|
|
self.exc_type_module = None
|
|
|
|
if exc_type and issubclass(exc_type, SyntaxError):
|
|
# Handle SyntaxError's specially
|
|
self.filename = exc_value.filename
|
|
lno = exc_value.lineno
|
|
self.lineno = str(lno) if lno is not None else None
|
|
end_lno = exc_value.end_lineno
|
|
self.end_lineno = str(end_lno) if end_lno is not None else None
|
|
self.text = exc_value.text
|
|
self.offset = exc_value.offset
|
|
self.end_offset = exc_value.end_offset
|
|
self.msg = exc_value.msg
|
|
self._is_syntax_error = True
|
|
elif exc_type and issubclass(exc_type, ImportError) and \
|
|
getattr(exc_value, "name_from", None) is not None:
|
|
wrong_name = getattr(exc_value, "name_from", None)
|
|
suggestion = _compute_suggestion_error(exc_value, exc_traceback, wrong_name)
|
|
if suggestion:
|
|
self._str += f". Did you mean: '{suggestion}'?"
|
|
elif exc_type and issubclass(exc_type, (NameError, AttributeError)) and \
|
|
getattr(exc_value, "name", None) is not None:
|
|
wrong_name = getattr(exc_value, "name", None)
|
|
suggestion = _compute_suggestion_error(exc_value, exc_traceback, wrong_name)
|
|
if suggestion:
|
|
self._str += f". Did you mean: '{suggestion}'?"
|
|
if issubclass(exc_type, NameError):
|
|
wrong_name = getattr(exc_value, "name", None)
|
|
if wrong_name is not None and wrong_name in sys.stdlib_module_names:
|
|
if suggestion:
|
|
self._str += f" Or did you forget to import '{wrong_name}'?"
|
|
else:
|
|
self._str += f". Did you forget to import '{wrong_name}'?"
|
|
if lookup_lines:
|
|
self._load_lines()
|
|
self.__suppress_context__ = \
|
|
exc_value.__suppress_context__ if exc_value is not None else False
|
|
|
|
# Convert __cause__ and __context__ to `TracebackExceptions`s, use a
|
|
# queue to avoid recursion (only the top-level call gets _seen == None)
|
|
if not is_recursive_call:
|
|
queue = [(self, exc_value)]
|
|
while queue:
|
|
te, e = queue.pop()
|
|
if (e and e.__cause__ is not None
|
|
and id(e.__cause__) not in _seen):
|
|
cause = TracebackException(
|
|
type(e.__cause__),
|
|
e.__cause__,
|
|
e.__cause__.__traceback__,
|
|
limit=limit,
|
|
lookup_lines=lookup_lines,
|
|
capture_locals=capture_locals,
|
|
max_group_width=max_group_width,
|
|
max_group_depth=max_group_depth,
|
|
_seen=_seen)
|
|
else:
|
|
cause = None
|
|
|
|
if compact:
|
|
need_context = (cause is None and
|
|
e is not None and
|
|
not e.__suppress_context__)
|
|
else:
|
|
need_context = True
|
|
if (e and e.__context__ is not None
|
|
and need_context and id(e.__context__) not in _seen):
|
|
context = TracebackException(
|
|
type(e.__context__),
|
|
e.__context__,
|
|
e.__context__.__traceback__,
|
|
limit=limit,
|
|
lookup_lines=lookup_lines,
|
|
capture_locals=capture_locals,
|
|
max_group_width=max_group_width,
|
|
max_group_depth=max_group_depth,
|
|
_seen=_seen)
|
|
else:
|
|
context = None
|
|
|
|
if e and isinstance(e, BaseExceptionGroup):
|
|
exceptions = []
|
|
for exc in e.exceptions:
|
|
texc = TracebackException(
|
|
type(exc),
|
|
exc,
|
|
exc.__traceback__,
|
|
limit=limit,
|
|
lookup_lines=lookup_lines,
|
|
capture_locals=capture_locals,
|
|
max_group_width=max_group_width,
|
|
max_group_depth=max_group_depth,
|
|
_seen=_seen)
|
|
exceptions.append(texc)
|
|
else:
|
|
exceptions = None
|
|
|
|
te.__cause__ = cause
|
|
te.__context__ = context
|
|
te.exceptions = exceptions
|
|
if cause:
|
|
queue.append((te.__cause__, e.__cause__))
|
|
if context:
|
|
queue.append((te.__context__, e.__context__))
|
|
if exceptions:
|
|
queue.extend(zip(te.exceptions, e.exceptions))
|
|
|
|
@classmethod
|
|
def from_exception(cls, exc, *args, **kwargs):
|
|
"""Create a TracebackException from an exception."""
|
|
return cls(type(exc), exc, exc.__traceback__, *args, **kwargs)
|
|
|
|
@property
|
|
def exc_type(self):
|
|
warnings.warn('Deprecated in 3.13. Use exc_type_str instead.',
|
|
DeprecationWarning, stacklevel=2)
|
|
return self._exc_type
|
|
|
|
@property
|
|
def exc_type_str(self):
|
|
if not self._have_exc_type:
|
|
return None
|
|
stype = self.exc_type_qualname
|
|
smod = self.exc_type_module
|
|
if smod not in ("__main__", "builtins"):
|
|
if not isinstance(smod, str):
|
|
smod = "<unknown>"
|
|
stype = smod + '.' + stype
|
|
return stype
|
|
|
|
def _load_lines(self):
|
|
"""Private API. force all lines in the stack to be loaded."""
|
|
for frame in self.stack:
|
|
frame.line
|
|
|
|
def __eq__(self, other):
|
|
if isinstance(other, TracebackException):
|
|
return self.__dict__ == other.__dict__
|
|
return NotImplemented
|
|
|
|
def __str__(self):
|
|
return self._str
|
|
|
|
def format_exception_only(self, *, show_group=False, _depth=0, **kwargs):
|
|
"""Format the exception part of the traceback.
|
|
|
|
The return value is a generator of strings, each ending in a newline.
|
|
|
|
Generator yields the exception message.
|
|
For :exc:`SyntaxError` exceptions, it
|
|
also yields (before the exception message)
|
|
several lines that (when printed)
|
|
display detailed information about where the syntax error occurred.
|
|
Following the message, generator also yields
|
|
all the exception's ``__notes__``.
|
|
|
|
When *show_group* is ``True``, and the exception is an instance of
|
|
:exc:`BaseExceptionGroup`, the nested exceptions are included as
|
|
well, recursively, with indentation relative to their nesting depth.
|
|
"""
|
|
colorize = kwargs.get("colorize", False)
|
|
|
|
indent = 3 * _depth * ' '
|
|
if not self._have_exc_type:
|
|
yield indent + _format_final_exc_line(None, self._str, colorize=colorize)
|
|
return
|
|
|
|
stype = self.exc_type_str
|
|
if not self._is_syntax_error:
|
|
if _depth > 0:
|
|
# Nested exceptions needs correct handling of multiline messages.
|
|
formatted = _format_final_exc_line(
|
|
stype, self._str, insert_final_newline=False, colorize=colorize
|
|
).split('\n')
|
|
yield from [
|
|
indent + l + '\n'
|
|
for l in formatted
|
|
]
|
|
else:
|
|
yield _format_final_exc_line(stype, self._str, colorize=colorize)
|
|
else:
|
|
yield from [indent + l for l in self._format_syntax_error(stype, colorize=colorize)]
|
|
|
|
if (
|
|
isinstance(self.__notes__, collections.abc.Sequence)
|
|
and not isinstance(self.__notes__, (str, bytes))
|
|
):
|
|
for note in self.__notes__:
|
|
note = _safe_string(note, 'note')
|
|
yield from [indent + l + '\n' for l in note.split('\n')]
|
|
elif self.__notes__ is not None:
|
|
yield indent + "{}\n".format(_safe_string(self.__notes__, '__notes__', func=repr))
|
|
|
|
if self.exceptions and show_group:
|
|
for ex in self.exceptions:
|
|
yield from ex.format_exception_only(show_group=show_group, _depth=_depth+1, colorize=colorize)
|
|
|
|
def _format_syntax_error(self, stype, **kwargs):
|
|
"""Format SyntaxError exceptions (internal helper)."""
|
|
# Show exactly where the problem was found.
|
|
colorize = kwargs.get("colorize", False)
|
|
filename_suffix = ''
|
|
if self.lineno is not None:
|
|
if colorize:
|
|
yield ' File {}"{}"{}, line {}{}{}\n'.format(
|
|
_ANSIColors.MAGENTA,
|
|
self.filename or "<string>",
|
|
_ANSIColors.RESET,
|
|
_ANSIColors.MAGENTA,
|
|
self.lineno,
|
|
_ANSIColors.RESET,
|
|
)
|
|
else:
|
|
yield ' File "{}", line {}\n'.format(
|
|
self.filename or "<string>", self.lineno)
|
|
elif self.filename is not None:
|
|
filename_suffix = ' ({})'.format(self.filename)
|
|
|
|
text = self.text
|
|
if text is not None:
|
|
# text = " foo\n"
|
|
# rtext = " foo"
|
|
# ltext = "foo"
|
|
rtext = text.rstrip('\n')
|
|
ltext = rtext.lstrip(' \n\f')
|
|
spaces = len(rtext) - len(ltext)
|
|
if self.offset is None:
|
|
yield ' {}\n'.format(ltext)
|
|
else:
|
|
offset = self.offset
|
|
end_offset = self.end_offset if self.end_offset not in {None, 0} else offset
|
|
if self.text and offset > len(self.text):
|
|
offset = len(self.text) + 1
|
|
if self.text and end_offset > len(self.text):
|
|
end_offset = len(self.text) + 1
|
|
if offset >= end_offset or end_offset < 0:
|
|
end_offset = offset + 1
|
|
|
|
# Convert 1-based column offset to 0-based index into stripped text
|
|
colno = offset - 1 - spaces
|
|
end_colno = end_offset - 1 - spaces
|
|
caretspace = ' '
|
|
if colno >= 0:
|
|
# non-space whitespace (likes tabs) must be kept for alignment
|
|
caretspace = ((c if c.isspace() else ' ') for c in ltext[:colno])
|
|
start_color = end_color = ""
|
|
if colorize:
|
|
# colorize from colno to end_colno
|
|
ltext = (
|
|
ltext[:colno] +
|
|
_ANSIColors.BOLD_RED + ltext[colno:end_colno] + _ANSIColors.RESET +
|
|
ltext[end_colno:]
|
|
)
|
|
start_color = _ANSIColors.BOLD_RED
|
|
end_color = _ANSIColors.RESET
|
|
yield ' {}\n'.format(ltext)
|
|
yield ' {}{}{}{}\n'.format(
|
|
"".join(caretspace),
|
|
start_color,
|
|
('^' * (end_colno - colno)),
|
|
end_color,
|
|
)
|
|
else:
|
|
yield ' {}\n'.format(ltext)
|
|
msg = self.msg or "<no detail available>"
|
|
if colorize:
|
|
yield "{}{}{}: {}{}{}{}\n".format(
|
|
_ANSIColors.BOLD_MAGENTA,
|
|
stype,
|
|
_ANSIColors.RESET,
|
|
_ANSIColors.MAGENTA,
|
|
msg,
|
|
_ANSIColors.RESET,
|
|
filename_suffix)
|
|
else:
|
|
yield "{}: {}{}\n".format(stype, msg, filename_suffix)
|
|
|
|
def format(self, *, chain=True, _ctx=None, **kwargs):
|
|
"""Format the exception.
|
|
|
|
If chain is not *True*, *__cause__* and *__context__* will not be formatted.
|
|
|
|
The return value is a generator of strings, each ending in a newline and
|
|
some containing internal newlines. `print_exception` is a wrapper around
|
|
this method which just prints the lines to a file.
|
|
|
|
The message indicating which exception occurred is always the last
|
|
string in the output.
|
|
"""
|
|
colorize = kwargs.get("colorize", False)
|
|
if _ctx is None:
|
|
_ctx = _ExceptionPrintContext()
|
|
|
|
output = []
|
|
exc = self
|
|
if chain:
|
|
while exc:
|
|
if exc.__cause__ is not None:
|
|
chained_msg = _cause_message
|
|
chained_exc = exc.__cause__
|
|
elif (exc.__context__ is not None and
|
|
not exc.__suppress_context__):
|
|
chained_msg = _context_message
|
|
chained_exc = exc.__context__
|
|
else:
|
|
chained_msg = None
|
|
chained_exc = None
|
|
|
|
output.append((chained_msg, exc))
|
|
exc = chained_exc
|
|
else:
|
|
output.append((None, exc))
|
|
|
|
for msg, exc in reversed(output):
|
|
if msg is not None:
|
|
yield from _ctx.emit(msg)
|
|
if exc.exceptions is None:
|
|
if exc.stack:
|
|
yield from _ctx.emit('Traceback (most recent call last):\n')
|
|
yield from _ctx.emit(exc.stack.format(colorize=colorize))
|
|
yield from _ctx.emit(exc.format_exception_only(colorize=colorize))
|
|
elif _ctx.exception_group_depth > self.max_group_depth:
|
|
# exception group, but depth exceeds limit
|
|
yield from _ctx.emit(
|
|
f"... (max_group_depth is {self.max_group_depth})\n")
|
|
else:
|
|
# format exception group
|
|
is_toplevel = (_ctx.exception_group_depth == 0)
|
|
if is_toplevel:
|
|
_ctx.exception_group_depth += 1
|
|
|
|
if exc.stack:
|
|
yield from _ctx.emit(
|
|
'Exception Group Traceback (most recent call last):\n',
|
|
margin_char = '+' if is_toplevel else None)
|
|
yield from _ctx.emit(exc.stack.format(colorize=colorize))
|
|
|
|
yield from _ctx.emit(exc.format_exception_only(colorize=colorize))
|
|
num_excs = len(exc.exceptions)
|
|
if num_excs <= self.max_group_width:
|
|
n = num_excs
|
|
else:
|
|
n = self.max_group_width + 1
|
|
_ctx.need_close = False
|
|
for i in range(n):
|
|
last_exc = (i == n-1)
|
|
if last_exc:
|
|
# The closing frame may be added by a recursive call
|
|
_ctx.need_close = True
|
|
|
|
if self.max_group_width is not None:
|
|
truncated = (i >= self.max_group_width)
|
|
else:
|
|
truncated = False
|
|
title = f'{i+1}' if not truncated else '...'
|
|
yield (_ctx.indent() +
|
|
('+-' if i==0 else ' ') +
|
|
f'+---------------- {title} ----------------\n')
|
|
_ctx.exception_group_depth += 1
|
|
if not truncated:
|
|
yield from exc.exceptions[i].format(chain=chain, _ctx=_ctx)
|
|
else:
|
|
remaining = num_excs - self.max_group_width
|
|
plural = 's' if remaining > 1 else ''
|
|
yield from _ctx.emit(
|
|
f"and {remaining} more exception{plural}\n")
|
|
|
|
if last_exc and _ctx.need_close:
|
|
yield (_ctx.indent() +
|
|
"+------------------------------------\n")
|
|
_ctx.need_close = False
|
|
_ctx.exception_group_depth -= 1
|
|
|
|
if is_toplevel:
|
|
assert _ctx.exception_group_depth == 1
|
|
_ctx.exception_group_depth = 0
|
|
|
|
|
|
def print(self, *, file=None, chain=True, **kwargs):
|
|
"""Print the result of self.format(chain=chain) to 'file'."""
|
|
colorize = kwargs.get("colorize", False)
|
|
if file is None:
|
|
file = sys.stderr
|
|
for line in self.format(chain=chain, colorize=colorize):
|
|
print(line, file=file, end="")
|
|
|
|
|
|
_MAX_CANDIDATE_ITEMS = 750
|
|
_MAX_STRING_SIZE = 40
|
|
_MOVE_COST = 2
|
|
_CASE_COST = 1
|
|
|
|
|
|
def _substitution_cost(ch_a, ch_b):
|
|
if ch_a == ch_b:
|
|
return 0
|
|
if ch_a.lower() == ch_b.lower():
|
|
return _CASE_COST
|
|
return _MOVE_COST
|
|
|
|
|
|
def _compute_suggestion_error(exc_value, tb, wrong_name):
|
|
if wrong_name is None or not isinstance(wrong_name, str):
|
|
return None
|
|
if isinstance(exc_value, AttributeError):
|
|
obj = exc_value.obj
|
|
try:
|
|
d = dir(obj)
|
|
except Exception:
|
|
return None
|
|
elif isinstance(exc_value, ImportError):
|
|
try:
|
|
mod = __import__(exc_value.name)
|
|
d = dir(mod)
|
|
except Exception:
|
|
return None
|
|
else:
|
|
assert isinstance(exc_value, NameError)
|
|
# find most recent frame
|
|
if tb is None:
|
|
return None
|
|
while tb.tb_next is not None:
|
|
tb = tb.tb_next
|
|
frame = tb.tb_frame
|
|
d = (
|
|
list(frame.f_locals)
|
|
+ list(frame.f_globals)
|
|
+ list(frame.f_builtins)
|
|
)
|
|
|
|
# Check first if we are in a method and the instance
|
|
# has the wrong name as attribute
|
|
if 'self' in frame.f_locals:
|
|
self = frame.f_locals['self']
|
|
if hasattr(self, wrong_name):
|
|
return f"self.{wrong_name}"
|
|
|
|
try:
|
|
import _suggestions
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
return _suggestions._generate_suggestions(d, wrong_name)
|
|
|
|
# Compute closest match
|
|
|
|
if len(d) > _MAX_CANDIDATE_ITEMS:
|
|
return None
|
|
wrong_name_len = len(wrong_name)
|
|
if wrong_name_len > _MAX_STRING_SIZE:
|
|
return None
|
|
best_distance = wrong_name_len
|
|
suggestion = None
|
|
for possible_name in d:
|
|
if possible_name == wrong_name:
|
|
# A missing attribute is "found". Don't suggest it (see GH-88821).
|
|
continue
|
|
# No more than 1/3 of the involved characters should need changed.
|
|
max_distance = (len(possible_name) + wrong_name_len + 3) * _MOVE_COST // 6
|
|
# Don't take matches we've already beaten.
|
|
max_distance = min(max_distance, best_distance - 1)
|
|
current_distance = _levenshtein_distance(wrong_name, possible_name, max_distance)
|
|
if current_distance > max_distance:
|
|
continue
|
|
if not suggestion or current_distance < best_distance:
|
|
suggestion = possible_name
|
|
best_distance = current_distance
|
|
return suggestion
|
|
|
|
|
|
def _levenshtein_distance(a, b, max_cost):
|
|
# A Python implementation of Python/suggestions.c:levenshtein_distance.
|
|
|
|
# Both strings are the same
|
|
if a == b:
|
|
return 0
|
|
|
|
# Trim away common affixes
|
|
pre = 0
|
|
while a[pre:] and b[pre:] and a[pre] == b[pre]:
|
|
pre += 1
|
|
a = a[pre:]
|
|
b = b[pre:]
|
|
post = 0
|
|
while a[:post or None] and b[:post or None] and a[post-1] == b[post-1]:
|
|
post -= 1
|
|
a = a[:post or None]
|
|
b = b[:post or None]
|
|
if not a or not b:
|
|
return _MOVE_COST * (len(a) + len(b))
|
|
if len(a) > _MAX_STRING_SIZE or len(b) > _MAX_STRING_SIZE:
|
|
return max_cost + 1
|
|
|
|
# Prefer shorter buffer
|
|
if len(b) < len(a):
|
|
a, b = b, a
|
|
|
|
# Quick fail when a match is impossible
|
|
if (len(b) - len(a)) * _MOVE_COST > max_cost:
|
|
return max_cost + 1
|
|
|
|
# Instead of producing the whole traditional len(a)-by-len(b)
|
|
# matrix, we can update just one row in place.
|
|
# Initialize the buffer row
|
|
row = list(range(_MOVE_COST, _MOVE_COST * (len(a) + 1), _MOVE_COST))
|
|
|
|
result = 0
|
|
for bindex in range(len(b)):
|
|
bchar = b[bindex]
|
|
distance = result = bindex * _MOVE_COST
|
|
minimum = sys.maxsize
|
|
for index in range(len(a)):
|
|
# 1) Previous distance in this row is cost(b[:b_index], a[:index])
|
|
substitute = distance + _substitution_cost(bchar, a[index])
|
|
# 2) cost(b[:b_index], a[:index+1]) from previous row
|
|
distance = row[index]
|
|
# 3) existing result is cost(b[:b_index+1], a[index])
|
|
|
|
insert_delete = min(result, distance) + _MOVE_COST
|
|
result = min(insert_delete, substitute)
|
|
|
|
# cost(b[:b_index+1], a[:index+1])
|
|
row[index] = result
|
|
if result < minimum:
|
|
minimum = result
|
|
if minimum > max_cost:
|
|
# Everything in this row is too big, so bail early.
|
|
return max_cost + 1
|
|
return result
|