604 lines
20 KiB
Python
604 lines
20 KiB
Python
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# traceback_exception_init() adapted from trio
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#
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# _ExceptionPrintContext and traceback_exception_format() copied from the standard
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# library
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from __future__ import annotations
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import collections.abc
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import sys
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import textwrap
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import traceback
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from functools import singledispatch
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from types import TracebackType
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from typing import Any, List, Optional
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from ._exceptions import BaseExceptionGroup
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max_group_width = 15
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max_group_depth = 10
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_cause_message = (
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"\nThe above exception was the direct cause of the following exception:\n\n"
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)
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_context_message = (
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"\nDuring handling of the above exception, another exception occurred:\n\n"
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)
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def _format_final_exc_line(etype, value):
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valuestr = _safe_string(value, "exception")
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if value is None or not valuestr:
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line = f"{etype}\n"
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else:
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line = f"{etype}: {valuestr}\n"
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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 BaseException:
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return f"<{what} {func.__name__}() failed>"
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class _ExceptionPrintContext:
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def __init__(self):
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self.seen = set()
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self.exception_group_depth = 0
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self.need_close = False
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def indent(self):
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return " " * (2 * self.exception_group_depth)
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def emit(self, text_gen, margin_char=None):
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if margin_char is None:
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margin_char = "|"
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indent_str = self.indent()
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if self.exception_group_depth:
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indent_str += margin_char + " "
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if isinstance(text_gen, str):
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yield textwrap.indent(text_gen, indent_str, lambda line: True)
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else:
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for text in text_gen:
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yield textwrap.indent(text, indent_str, lambda line: True)
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def exceptiongroup_excepthook(
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etype: type[BaseException], value: BaseException, tb: TracebackType | None
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) -> None:
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sys.stderr.write("".join(traceback.format_exception(etype, value, tb)))
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class PatchedTracebackException(traceback.TracebackException):
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def __init__(
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self,
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exc_type: type[BaseException],
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exc_value: BaseException,
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exc_traceback: TracebackType | None,
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*,
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limit: int | None = None,
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lookup_lines: bool = True,
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capture_locals: bool = False,
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compact: bool = False,
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_seen: set[int] | None = None,
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) -> None:
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kwargs: dict[str, Any] = {}
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if sys.version_info >= (3, 10):
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kwargs["compact"] = compact
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is_recursive_call = _seen is not None
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if _seen is None:
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_seen = set()
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_seen.add(id(exc_value))
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self.stack = traceback.StackSummary.extract(
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traceback.walk_tb(exc_traceback),
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limit=limit,
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lookup_lines=lookup_lines,
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capture_locals=capture_locals,
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)
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self.exc_type = exc_type
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# Capture now to permit freeing resources: only complication is in the
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# unofficial API _format_final_exc_line
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self._str = _safe_string(exc_value, "exception")
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try:
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self.__notes__ = getattr(exc_value, "__notes__", None)
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except KeyError:
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# Workaround for https://github.com/python/cpython/issues/98778 on Python
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# <= 3.9, and some 3.10 and 3.11 patch versions.
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HTTPError = getattr(sys.modules.get("urllib.error", None), "HTTPError", ())
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if sys.version_info[:2] <= (3, 11) and isinstance(exc_value, HTTPError):
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self.__notes__ = None
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else:
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raise
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if exc_type and issubclass(exc_type, SyntaxError):
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# Handle SyntaxError's specially
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self.filename = exc_value.filename
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lno = exc_value.lineno
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self.lineno = str(lno) if lno is not None else None
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self.text = exc_value.text
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self.offset = exc_value.offset
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self.msg = exc_value.msg
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if sys.version_info >= (3, 10):
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end_lno = exc_value.end_lineno
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self.end_lineno = str(end_lno) if end_lno is not None else None
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self.end_offset = exc_value.end_offset
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elif (
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exc_type
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and issubclass(exc_type, (NameError, AttributeError))
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and getattr(exc_value, "name", None) is not None
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):
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suggestion = _compute_suggestion_error(exc_value, exc_traceback)
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if suggestion:
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self._str += f". Did you mean: '{suggestion}'?"
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if lookup_lines:
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# Force all lines in the stack to be loaded
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for frame in self.stack:
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frame.line
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self.__suppress_context__ = (
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exc_value.__suppress_context__ if exc_value is not None else False
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)
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# Convert __cause__ and __context__ to `TracebackExceptions`s, use a
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# queue to avoid recursion (only the top-level call gets _seen == None)
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if not is_recursive_call:
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queue = [(self, exc_value)]
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while queue:
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te, e = queue.pop()
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if e and e.__cause__ is not None and id(e.__cause__) not in _seen:
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cause = PatchedTracebackException(
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type(e.__cause__),
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e.__cause__,
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e.__cause__.__traceback__,
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limit=limit,
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lookup_lines=lookup_lines,
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capture_locals=capture_locals,
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_seen=_seen,
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)
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else:
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cause = None
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if compact:
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need_context = (
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cause is None and e is not None and not e.__suppress_context__
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)
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else:
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need_context = True
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if (
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e
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and e.__context__ is not None
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and need_context
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and id(e.__context__) not in _seen
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):
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context = PatchedTracebackException(
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type(e.__context__),
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e.__context__,
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e.__context__.__traceback__,
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limit=limit,
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lookup_lines=lookup_lines,
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capture_locals=capture_locals,
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_seen=_seen,
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)
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else:
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context = None
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# Capture each of the exceptions in the ExceptionGroup along with each
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# of their causes and contexts
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if e and isinstance(e, BaseExceptionGroup):
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exceptions = []
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for exc in e.exceptions:
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texc = PatchedTracebackException(
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type(exc),
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exc,
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exc.__traceback__,
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lookup_lines=lookup_lines,
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capture_locals=capture_locals,
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_seen=_seen,
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)
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exceptions.append(texc)
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else:
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exceptions = None
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te.__cause__ = cause
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te.__context__ = context
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te.exceptions = exceptions
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if cause:
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queue.append((te.__cause__, e.__cause__))
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if context:
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queue.append((te.__context__, e.__context__))
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if exceptions:
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queue.extend(zip(te.exceptions, e.exceptions))
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def format(self, *, chain=True, _ctx=None):
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if _ctx is None:
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_ctx = _ExceptionPrintContext()
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output = []
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exc = self
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if chain:
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while exc:
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if exc.__cause__ is not None:
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chained_msg = _cause_message
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chained_exc = exc.__cause__
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elif exc.__context__ is not None and not exc.__suppress_context__:
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chained_msg = _context_message
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chained_exc = exc.__context__
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else:
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chained_msg = None
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chained_exc = None
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output.append((chained_msg, exc))
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exc = chained_exc
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else:
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output.append((None, exc))
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for msg, exc in reversed(output):
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if msg is not None:
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yield from _ctx.emit(msg)
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if exc.exceptions is None:
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if exc.stack:
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yield from _ctx.emit("Traceback (most recent call last):\n")
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yield from _ctx.emit(exc.stack.format())
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yield from _ctx.emit(exc.format_exception_only())
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elif _ctx.exception_group_depth > max_group_depth:
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# exception group, but depth exceeds limit
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yield from _ctx.emit(f"... (max_group_depth is {max_group_depth})\n")
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else:
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# format exception group
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is_toplevel = _ctx.exception_group_depth == 0
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if is_toplevel:
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_ctx.exception_group_depth += 1
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if exc.stack:
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yield from _ctx.emit(
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"Exception Group Traceback (most recent call last):\n",
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margin_char="+" if is_toplevel else None,
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)
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yield from _ctx.emit(exc.stack.format())
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yield from _ctx.emit(exc.format_exception_only())
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num_excs = len(exc.exceptions)
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if num_excs <= max_group_width:
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n = num_excs
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else:
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n = max_group_width + 1
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_ctx.need_close = False
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for i in range(n):
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last_exc = i == n - 1
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if last_exc:
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# The closing frame may be added by a recursive call
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_ctx.need_close = True
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if max_group_width is not None:
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truncated = i >= max_group_width
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else:
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truncated = False
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title = f"{i + 1}" if not truncated else "..."
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yield (
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_ctx.indent()
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+ ("+-" if i == 0 else " ")
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+ f"+---------------- {title} ----------------\n"
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)
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_ctx.exception_group_depth += 1
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if not truncated:
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yield from exc.exceptions[i].format(chain=chain, _ctx=_ctx)
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else:
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remaining = num_excs - max_group_width
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plural = "s" if remaining > 1 else ""
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yield from _ctx.emit(
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f"and {remaining} more exception{plural}\n"
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)
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if last_exc and _ctx.need_close:
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yield _ctx.indent() + "+------------------------------------\n"
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_ctx.need_close = False
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_ctx.exception_group_depth -= 1
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if is_toplevel:
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assert _ctx.exception_group_depth == 1
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_ctx.exception_group_depth = 0
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def format_exception_only(self):
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"""Format the exception part of the traceback.
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The return value is a generator of strings, each ending in a newline.
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Normally, the generator emits a single string; however, for
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SyntaxError exceptions, it emits several lines that (when
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printed) display detailed information about where the syntax
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error occurred.
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The message indicating which exception occurred is always the last
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string in the output.
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"""
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if self.exc_type is None:
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yield traceback._format_final_exc_line(None, self._str)
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return
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stype = self.exc_type.__qualname__
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smod = self.exc_type.__module__
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if smod not in ("__main__", "builtins"):
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if not isinstance(smod, str):
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smod = "<unknown>"
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stype = smod + "." + stype
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if not issubclass(self.exc_type, SyntaxError):
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yield _format_final_exc_line(stype, self._str)
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elif traceback_exception_format_syntax_error is not None:
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yield from traceback_exception_format_syntax_error(self, stype)
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else:
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yield from traceback_exception_original_format_exception_only(self)
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if isinstance(self.__notes__, collections.abc.Sequence):
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for note in self.__notes__:
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note = _safe_string(note, "note")
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yield from [line + "\n" for line in note.split("\n")]
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elif self.__notes__ is not None:
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yield _safe_string(self.__notes__, "__notes__", func=repr)
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traceback_exception_original_format = traceback.TracebackException.format
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traceback_exception_original_format_exception_only = (
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traceback.TracebackException.format_exception_only
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)
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traceback_exception_format_syntax_error = getattr(
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traceback.TracebackException, "_format_syntax_error", None
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)
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if sys.excepthook is sys.__excepthook__:
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traceback.TracebackException.__init__ = ( # type: ignore[assignment]
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PatchedTracebackException.__init__
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)
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traceback.TracebackException.format = ( # type: ignore[assignment]
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PatchedTracebackException.format
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)
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traceback.TracebackException.format_exception_only = ( # type: ignore[assignment]
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PatchedTracebackException.format_exception_only
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)
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sys.excepthook = exceptiongroup_excepthook
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# Ubuntu's system Python has a sitecustomize.py file that imports
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# apport_python_hook and replaces sys.excepthook.
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#
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# The custom hook captures the error for crash reporting, and then calls
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# sys.__excepthook__ to actually print the error.
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#
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# We don't mind it capturing the error for crash reporting, but we want to
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# take over printing the error. So we monkeypatch the apport_python_hook
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# module so that instead of calling sys.__excepthook__, it calls our custom
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# hook.
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#
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# More details: https://github.com/python-trio/trio/issues/1065
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if getattr(sys.excepthook, "__name__", None) in (
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"apport_excepthook",
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# on ubuntu 22.10 the hook was renamed to partial_apport_excepthook
|
||
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|
"partial_apport_excepthook",
|
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|
):
|
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|
# patch traceback like above
|
||
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|
traceback.TracebackException.__init__ = ( # type: ignore[assignment]
|
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|
|
PatchedTracebackException.__init__
|
||
|
|
)
|
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|
|
traceback.TracebackException.format = ( # type: ignore[assignment]
|
||
|
|
PatchedTracebackException.format
|
||
|
|
)
|
||
|
|
traceback.TracebackException.format_exception_only = ( # type: ignore[assignment]
|
||
|
|
PatchedTracebackException.format_exception_only
|
||
|
|
)
|
||
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|
||
|
|
from types import ModuleType
|
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|
|
|
||
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|
import apport_python_hook
|
||
|
|
|
||
|
|
assert sys.excepthook is apport_python_hook.apport_excepthook
|
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|
|
|
||
|
|
# monkeypatch the sys module that apport has imported
|
||
|
|
fake_sys = ModuleType("exceptiongroup_fake_sys")
|
||
|
|
fake_sys.__dict__.update(sys.__dict__)
|
||
|
|
fake_sys.__excepthook__ = exceptiongroup_excepthook
|
||
|
|
apport_python_hook.sys = fake_sys
|
||
|
|
|
||
|
|
|
||
|
|
@singledispatch
|
||
|
|
def format_exception_only(__exc: BaseException) -> List[str]:
|
||
|
|
return list(
|
||
|
|
PatchedTracebackException(
|
||
|
|
type(__exc), __exc, None, compact=True
|
||
|
|
).format_exception_only()
|
||
|
|
)
|
||
|
|
|
||
|
|
|
||
|
|
@format_exception_only.register
|
||
|
|
def _(__exc: type, value: BaseException) -> List[str]:
|
||
|
|
return format_exception_only(value)
|
||
|
|
|
||
|
|
|
||
|
|
@singledispatch
|
||
|
|
def format_exception(
|
||
|
|
__exc: BaseException,
|
||
|
|
limit: Optional[int] = None,
|
||
|
|
chain: bool = True,
|
||
|
|
) -> List[str]:
|
||
|
|
return list(
|
||
|
|
PatchedTracebackException(
|
||
|
|
type(__exc), __exc, __exc.__traceback__, limit=limit, compact=True
|
||
|
|
).format(chain=chain)
|
||
|
|
)
|
||
|
|
|
||
|
|
|
||
|
|
@format_exception.register
|
||
|
|
def _(
|
||
|
|
__exc: type,
|
||
|
|
value: BaseException,
|
||
|
|
tb: TracebackType,
|
||
|
|
limit: Optional[int] = None,
|
||
|
|
chain: bool = True,
|
||
|
|
) -> List[str]:
|
||
|
|
return format_exception(value, limit, chain)
|
||
|
|
|
||
|
|
|
||
|
|
@singledispatch
|
||
|
|
def print_exception(
|
||
|
|
__exc: BaseException,
|
||
|
|
limit: Optional[int] = None,
|
||
|
|
file: Any = None,
|
||
|
|
chain: bool = True,
|
||
|
|
) -> None:
|
||
|
|
if file is None:
|
||
|
|
file = sys.stderr
|
||
|
|
|
||
|
|
for line in PatchedTracebackException(
|
||
|
|
type(__exc), __exc, __exc.__traceback__, limit=limit
|
||
|
|
).format(chain=chain):
|
||
|
|
print(line, file=file, end="")
|
||
|
|
|
||
|
|
|
||
|
|
@print_exception.register
|
||
|
|
def _(
|
||
|
|
__exc: type,
|
||
|
|
value: BaseException,
|
||
|
|
tb: TracebackType,
|
||
|
|
limit: Optional[int] = None,
|
||
|
|
file: Any = None,
|
||
|
|
chain: bool = True,
|
||
|
|
) -> None:
|
||
|
|
print_exception(value, limit, file, chain)
|
||
|
|
|
||
|
|
|
||
|
|
def print_exc(
|
||
|
|
limit: Optional[int] = None,
|
||
|
|
file: Any | None = None,
|
||
|
|
chain: bool = True,
|
||
|
|
) -> None:
|
||
|
|
value = sys.exc_info()[1]
|
||
|
|
print_exception(value, limit, file, chain)
|
||
|
|
|
||
|
|
|
||
|
|
# Python levenshtein edit distance code for NameError/AttributeError
|
||
|
|
# suggestions, backported from 3.12
|
||
|
|
|
||
|
|
_MAX_CANDIDATE_ITEMS = 750
|
||
|
|
_MAX_STRING_SIZE = 40
|
||
|
|
_MOVE_COST = 2
|
||
|
|
_CASE_COST = 1
|
||
|
|
_SENTINEL = object()
|
||
|
|
|
||
|
|
|
||
|
|
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 = getattr(exc_value, "name", None)
|
||
|
|
if wrong_name is None or not isinstance(wrong_name, str):
|
||
|
|
return None
|
||
|
|
if isinstance(exc_value, AttributeError):
|
||
|
|
obj = getattr(exc_value, "obj", _SENTINEL)
|
||
|
|
if obj is _SENTINEL:
|
||
|
|
return None
|
||
|
|
obj = exc_value.obj
|
||
|
|
try:
|
||
|
|
d = dir(obj)
|
||
|
|
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)
|
||
|
|
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
|