300 lines
9.3 KiB
Python
300 lines
9.3 KiB
Python
|
# exceptions.py
|
||
|
|
|
||
|
|
import re
|
||
|
|
import sys
|
||
|
|
import typing
|
||
|
|
|
||
|
|
from .util import (
|
||
|
|
col,
|
||
|
|
line,
|
||
|
|
lineno,
|
||
|
|
_collapse_string_to_ranges,
|
||
|
|
replaced_by_pep8,
|
||
|
|
)
|
||
|
|
from .unicode import pyparsing_unicode as ppu
|
||
|
|
|
||
|
|
|
||
|
|
class ExceptionWordUnicode(ppu.Latin1, ppu.LatinA, ppu.LatinB, ppu.Greek, ppu.Cyrillic):
|
||
|
|
pass
|
||
|
|
|
||
|
|
|
||
|
|
_extract_alphanums = _collapse_string_to_ranges(ExceptionWordUnicode.alphanums)
|
||
|
|
_exception_word_extractor = re.compile("([" + _extract_alphanums + "]{1,16})|.")
|
||
|
|
|
||
|
|
|
||
|
|
class ParseBaseException(Exception):
|
||
|
|
"""base exception class for all parsing runtime exceptions"""
|
||
|
|
|
||
|
|
loc: int
|
||
|
|
msg: str
|
||
|
|
pstr: str
|
||
|
|
parser_element: typing.Any # "ParserElement"
|
||
|
|
args: typing.Tuple[str, int, typing.Optional[str]]
|
||
|
|
|
||
|
|
__slots__ = (
|
||
|
|
"loc",
|
||
|
|
"msg",
|
||
|
|
"pstr",
|
||
|
|
"parser_element",
|
||
|
|
"args",
|
||
|
|
)
|
||
|
|
|
||
|
|
# Performance tuning: we construct a *lot* of these, so keep this
|
||
|
|
# constructor as small and fast as possible
|
||
|
|
def __init__(
|
||
|
|
self,
|
||
|
|
pstr: str,
|
||
|
|
loc: int = 0,
|
||
|
|
msg: typing.Optional[str] = None,
|
||
|
|
elem=None,
|
||
|
|
):
|
||
|
|
self.loc = loc
|
||
|
|
if msg is None:
|
||
|
|
self.msg = pstr
|
||
|
|
self.pstr = ""
|
||
|
|
else:
|
||
|
|
self.msg = msg
|
||
|
|
self.pstr = pstr
|
||
|
|
self.parser_element = elem
|
||
|
|
self.args = (pstr, loc, msg)
|
||
|
|
|
||
|
|
@staticmethod
|
||
|
|
def explain_exception(exc, depth=16):
|
||
|
|
"""
|
||
|
|
Method to take an exception and translate the Python internal traceback into a list
|
||
|
|
of the pyparsing expressions that caused the exception to be raised.
|
||
|
|
|
||
|
|
Parameters:
|
||
|
|
|
||
|
|
- exc - exception raised during parsing (need not be a ParseException, in support
|
||
|
|
of Python exceptions that might be raised in a parse action)
|
||
|
|
- depth (default=16) - number of levels back in the stack trace to list expression
|
||
|
|
and function names; if None, the full stack trace names will be listed; if 0, only
|
||
|
|
the failing input line, marker, and exception string will be shown
|
||
|
|
|
||
|
|
Returns a multi-line string listing the ParserElements and/or function names in the
|
||
|
|
exception's stack trace.
|
||
|
|
"""
|
||
|
|
import inspect
|
||
|
|
from .core import ParserElement
|
||
|
|
|
||
|
|
if depth is None:
|
||
|
|
depth = sys.getrecursionlimit()
|
||
|
|
ret = []
|
||
|
|
if isinstance(exc, ParseBaseException):
|
||
|
|
ret.append(exc.line)
|
||
|
|
ret.append(" " * (exc.column - 1) + "^")
|
||
|
|
ret.append(f"{type(exc).__name__}: {exc}")
|
||
|
|
|
||
|
|
if depth > 0:
|
||
|
|
callers = inspect.getinnerframes(exc.__traceback__, context=depth)
|
||
|
|
seen = set()
|
||
|
|
for i, ff in enumerate(callers[-depth:]):
|
||
|
|
frm = ff[0]
|
||
|
|
|
||
|
|
f_self = frm.f_locals.get("self", None)
|
||
|
|
if isinstance(f_self, ParserElement):
|
||
|
|
if not frm.f_code.co_name.startswith(
|
||
|
|
("parseImpl", "_parseNoCache")
|
||
|
|
):
|
||
|
|
continue
|
||
|
|
if id(f_self) in seen:
|
||
|
|
continue
|
||
|
|
seen.add(id(f_self))
|
||
|
|
|
||
|
|
self_type = type(f_self)
|
||
|
|
ret.append(
|
||
|
|
f"{self_type.__module__}.{self_type.__name__} - {f_self}"
|
||
|
|
)
|
||
|
|
|
||
|
|
elif f_self is not None:
|
||
|
|
self_type = type(f_self)
|
||
|
|
ret.append(f"{self_type.__module__}.{self_type.__name__}")
|
||
|
|
|
||
|
|
else:
|
||
|
|
code = frm.f_code
|
||
|
|
if code.co_name in ("wrapper", "<module>"):
|
||
|
|
continue
|
||
|
|
|
||
|
|
ret.append(code.co_name)
|
||
|
|
|
||
|
|
depth -= 1
|
||
|
|
if not depth:
|
||
|
|
break
|
||
|
|
|
||
|
|
return "\n".join(ret)
|
||
|
|
|
||
|
|
@classmethod
|
||
|
|
def _from_exception(cls, pe):
|
||
|
|
"""
|
||
|
|
internal factory method to simplify creating one type of ParseException
|
||
|
|
from another - avoids having __init__ signature conflicts among subclasses
|
||
|
|
"""
|
||
|
|
return cls(pe.pstr, pe.loc, pe.msg, pe.parser_element)
|
||
|
|
|
||
|
|
@property
|
||
|
|
def line(self) -> str:
|
||
|
|
"""
|
||
|
|
Return the line of text where the exception occurred.
|
||
|
|
"""
|
||
|
|
return line(self.loc, self.pstr)
|
||
|
|
|
||
|
|
@property
|
||
|
|
def lineno(self) -> int:
|
||
|
|
"""
|
||
|
|
Return the 1-based line number of text where the exception occurred.
|
||
|
|
"""
|
||
|
|
return lineno(self.loc, self.pstr)
|
||
|
|
|
||
|
|
@property
|
||
|
|
def col(self) -> int:
|
||
|
|
"""
|
||
|
|
Return the 1-based column on the line of text where the exception occurred.
|
||
|
|
"""
|
||
|
|
return col(self.loc, self.pstr)
|
||
|
|
|
||
|
|
@property
|
||
|
|
def column(self) -> int:
|
||
|
|
"""
|
||
|
|
Return the 1-based column on the line of text where the exception occurred.
|
||
|
|
"""
|
||
|
|
return col(self.loc, self.pstr)
|
||
|
|
|
||
|
|
# pre-PEP8 compatibility
|
||
|
|
@property
|
||
|
|
def parserElement(self):
|
||
|
|
return self.parser_element
|
||
|
|
|
||
|
|
@parserElement.setter
|
||
|
|
def parserElement(self, elem):
|
||
|
|
self.parser_element = elem
|
||
|
|
|
||
|
|
def __str__(self) -> str:
|
||
|
|
if self.pstr:
|
||
|
|
if self.loc >= len(self.pstr):
|
||
|
|
foundstr = ", found end of text"
|
||
|
|
else:
|
||
|
|
# pull out next word at error location
|
||
|
|
found_match = _exception_word_extractor.match(self.pstr, self.loc)
|
||
|
|
if found_match is not None:
|
||
|
|
found = found_match.group(0)
|
||
|
|
else:
|
||
|
|
found = self.pstr[self.loc : self.loc + 1]
|
||
|
|
foundstr = (", found %r" % found).replace(r"\\", "\\")
|
||
|
|
else:
|
||
|
|
foundstr = ""
|
||
|
|
return f"{self.msg}{foundstr} (at char {self.loc}), (line:{self.lineno}, col:{self.column})"
|
||
|
|
|
||
|
|
def __repr__(self):
|
||
|
|
return str(self)
|
||
|
|
|
||
|
|
def mark_input_line(
|
||
|
|
self, marker_string: typing.Optional[str] = None, *, markerString: str = ">!<"
|
||
|
|
) -> str:
|
||
|
|
"""
|
||
|
|
Extracts the exception line from the input string, and marks
|
||
|
|
the location of the exception with a special symbol.
|
||
|
|
"""
|
||
|
|
markerString = marker_string if marker_string is not None else markerString
|
||
|
|
line_str = self.line
|
||
|
|
line_column = self.column - 1
|
||
|
|
if markerString:
|
||
|
|
line_str = "".join(
|
||
|
|
(line_str[:line_column], markerString, line_str[line_column:])
|
||
|
|
)
|
||
|
|
return line_str.strip()
|
||
|
|
|
||
|
|
def explain(self, depth=16) -> str:
|
||
|
|
"""
|
||
|
|
Method to translate the Python internal traceback into a list
|
||
|
|
of the pyparsing expressions that caused the exception to be raised.
|
||
|
|
|
||
|
|
Parameters:
|
||
|
|
|
||
|
|
- depth (default=16) - number of levels back in the stack trace to list expression
|
||
|
|
and function names; if None, the full stack trace names will be listed; if 0, only
|
||
|
|
the failing input line, marker, and exception string will be shown
|
||
|
|
|
||
|
|
Returns a multi-line string listing the ParserElements and/or function names in the
|
||
|
|
exception's stack trace.
|
||
|
|
|
||
|
|
Example::
|
||
|
|
|
||
|
|
expr = pp.Word(pp.nums) * 3
|
||
|
|
try:
|
||
|
|
expr.parse_string("123 456 A789")
|
||
|
|
except pp.ParseException as pe:
|
||
|
|
print(pe.explain(depth=0))
|
||
|
|
|
||
|
|
prints::
|
||
|
|
|
||
|
|
123 456 A789
|
||
|
|
^
|
||
|
|
ParseException: Expected W:(0-9), found 'A' (at char 8), (line:1, col:9)
|
||
|
|
|
||
|
|
Note: the diagnostic output will include string representations of the expressions
|
||
|
|
that failed to parse. These representations will be more helpful if you use `set_name` to
|
||
|
|
give identifiable names to your expressions. Otherwise they will use the default string
|
||
|
|
forms, which may be cryptic to read.
|
||
|
|
|
||
|
|
Note: pyparsing's default truncation of exception tracebacks may also truncate the
|
||
|
|
stack of expressions that are displayed in the ``explain`` output. To get the full listing
|
||
|
|
of parser expressions, you may have to set ``ParserElement.verbose_stacktrace = True``
|
||
|
|
"""
|
||
|
|
return self.explain_exception(self, depth)
|
||
|
|
|
||
|
|
# fmt: off
|
||
|
|
@replaced_by_pep8(mark_input_line)
|
||
|
|
def markInputline(self): ...
|
||
|
|
# fmt: on
|
||
|
|
|
||
|
|
|
||
|
|
class ParseException(ParseBaseException):
|
||
|
|
"""
|
||
|
|
Exception thrown when a parse expression doesn't match the input string
|
||
|
|
|
||
|
|
Example::
|
||
|
|
|
||
|
|
try:
|
||
|
|
Word(nums).set_name("integer").parse_string("ABC")
|
||
|
|
except ParseException as pe:
|
||
|
|
print(pe)
|
||
|
|
print("column: {}".format(pe.column))
|
||
|
|
|
||
|
|
prints::
|
||
|
|
|
||
|
|
Expected integer (at char 0), (line:1, col:1)
|
||
|
|
column: 1
|
||
|
|
|
||
|
|
"""
|
||
|
|
|
||
|
|
|
||
|
|
class ParseFatalException(ParseBaseException):
|
||
|
|
"""
|
||
|
|
User-throwable exception thrown when inconsistent parse content
|
||
|
|
is found; stops all parsing immediately
|
||
|
|
"""
|
||
|
|
|
||
|
|
|
||
|
|
class ParseSyntaxException(ParseFatalException):
|
||
|
|
"""
|
||
|
|
Just like :class:`ParseFatalException`, but thrown internally
|
||
|
|
when an :class:`ErrorStop<And._ErrorStop>` ('-' operator) indicates
|
||
|
|
that parsing is to stop immediately because an unbacktrackable
|
||
|
|
syntax error has been found.
|
||
|
|
"""
|
||
|
|
|
||
|
|
|
||
|
|
class RecursiveGrammarException(Exception):
|
||
|
|
"""
|
||
|
|
Exception thrown by :class:`ParserElement.validate` if the
|
||
|
|
grammar could be left-recursive; parser may need to enable
|
||
|
|
left recursion using :class:`ParserElement.enable_left_recursion<ParserElement.enable_left_recursion>`
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self, parseElementList):
|
||
|
|
self.parseElementTrace = parseElementList
|
||
|
|
|
||
|
|
def __str__(self) -> str:
|
||
|
|
return f"RecursiveGrammarException: {self.parseElementTrace}"
|