# Upstream repository: <https://github.com/efficios/normand>.
__author__ = "Philippe Proulx"
-__version__ = "0.14.0"
+__version__ = "0.15.0"
__all__ = [
"__author__",
"__version__",
"LabelsT",
"parse",
"ParseError",
+ "ParseErrorMessage",
"ParseResult",
"TextLocation",
"VariablesT",
)
-# A parsing error containing a message and a text location.
+# A parsing error message: a string and a text location.
+class ParseErrorMessage:
+ @classmethod
+ def _create(cls, text: str, text_loc: TextLocation):
+ self = cls.__new__(cls)
+ self._init(text, text_loc)
+ return self
+
+ def __init__(self, *args, **kwargs): # type: ignore
+ raise NotImplementedError
+
+ def _init(self, text: str, text_loc: TextLocation):
+ self._text = text
+ self._text_loc = text_loc
+
+ # Message text.
+ @property
+ def text(self):
+ return self._text
+
+ # Source text location.
+ @property
+ def text_location(self):
+ return self._text_loc
+
+
+# A parsing error containing one or more messages (`ParseErrorMessage`).
class ParseError(RuntimeError):
@classmethod
def _create(cls, msg: str, text_loc: TextLocation):
def _init(self, msg: str, text_loc: TextLocation):
super().__init__(msg)
- self._text_loc = text_loc
+ self._msgs = [] # type: List[ParseErrorMessage]
+ self._add_msg(msg, text_loc)
- # Source text location.
+ def _add_msg(self, msg: str, text_loc: TextLocation):
+ self._msgs.append(
+ ParseErrorMessage._create( # pyright: ignore[reportPrivateUsage]
+ msg, text_loc
+ )
+ )
+
+ # Parsing error messages.
+ #
+ # The first message is the most specific one.
@property
- def text_loc(self):
- return self._text_loc
+ def messages(self):
+ return self._msgs
# Raises a parsing error, forwarding the parameters to the constructor.
raise ParseError._create(msg, text_loc) # pyright: ignore[reportPrivateUsage]
+# Adds a message to the parsing error `exc`.
+def _add_error_msg(exc: ParseError, msg: str, text_loc: TextLocation):
+ exc._add_msg(msg, text_loc) # pyright: ignore[reportPrivateUsage]
+
+
+# Appends a message to the parsing error `exc` and reraises it.
+def _augment_error(exc: ParseError, msg: str, text_loc: TextLocation) -> NoReturn:
+ _add_error_msg(exc, msg, text_loc)
+ raise exc
+
+
# Variables dictionary type (for type hints).
VariablesT = Dict[str, Union[int, float]]
# Fixed-length number item instance.
class _FlNumItemInst:
- def __init__(self, item: _FlNum, offset_in_data: int, state: _GenState):
+ def __init__(
+ self,
+ item: _FlNum,
+ offset_in_data: int,
+ state: _GenState,
+ parse_error_msgs: List[ParseErrorMessage],
+ ):
self._item = item
self._offset_in_data = offset_in_data
self._state = state
+ self._parse_error_msgs = parse_error_msgs
@property
def item(self):
def state(self):
return self._state
+ @property
+ def parse_error_msgs(self):
+ return self._parse_error_msgs
+
# Generator of data and final state from a group item.
#
# because the expression refers to a "future" label: save the current
# offset in `self._data` (generated data) and a snapshot of the
# current state within `self._fl_num_item_insts` (`_FlNumItemInst`
-# object). _gen_fl_num_item_insts() will deal with this later.
+# object). _gen_fl_num_item_insts() will deal with this later. A
+# `_FlNumItemInst` instance also contains a snapshot of the current
+# parsing error messages (`self._parse_error_msgs`) which need to be
+# taken into account when handling the instance later.
#
# When handling the items of a group, keep a map of immediate label
# names to their offset. Then, after having processed all the items,
# "future" labels from the point of view of some fixed-length number
# item instance.
#
-# If an evaluation fails at this point, then it's a user error.
+# If an evaluation fails at this point, then it's a user error. Add
+# to the parsing error all the saved parsing error messages of the
+# instance. Those additional messages add precious context to the
+# error.
class _Gen:
def __init__(
self,
):
self._macro_defs = macro_defs
self._fl_num_item_insts = [] # type: List[_FlNumItemInst]
+ self._parse_error_msgs = [] # type: List[ParseErrorMessage]
self._gen(group, _GenState(variables, labels, offset, bo))
# Generated bytes.
data = self._gen_fl_num_item_inst_data(item, state)
except Exception:
self._fl_num_item_insts.append(
- _FlNumItemInst(item, len(self._data), copy.deepcopy(state))
+ _FlNumItemInst(
+ item,
+ len(self._data),
+ copy.deepcopy(state),
+ copy.deepcopy(self._parse_error_msgs),
+ )
)
# Reserve space in `self._data` for this instance
# Handles the macro expansion item `item`.
def _handle_macro_exp_item(self, item: _MacroExp, state: _GenState):
- # New state
- exp_state = self._eval_macro_exp_params(item, state)
+ parse_error_msg_text = "While expanding the macro `{}`:".format(item.name)
- # Process the contained group
- init_data_size = len(self._data)
- self._handle_item(self._macro_defs[item.name].group, exp_state)
+ try:
+ # New state
+ exp_state = self._eval_macro_exp_params(item, state)
+
+ # Process the contained group
+ init_data_size = len(self._data)
+ parse_error_msg = (
+ ParseErrorMessage._create( # pyright: ignore[reportPrivateUsage]
+ parse_error_msg_text, item.text_loc
+ )
+ )
+ self._parse_error_msgs.append(parse_error_msg)
+ self._handle_item(self._macro_defs[item.name].group, exp_state)
+ self._parse_error_msgs.pop()
+ except ParseError as exc:
+ _augment_error(exc, parse_error_msg_text, item.text_loc)
# Update state offset and return
state.offset += len(self._data) - init_data_size
def _gen_fl_num_item_insts(self):
for inst in self._fl_num_item_insts:
# Generate bytes
- data = self._gen_fl_num_item_inst_data(inst.item, inst.state)
+ try:
+ data = self._gen_fl_num_item_inst_data(inst.item, inst.state)
+ except ParseError as exc:
+ # Add all the saved parse error messages for this
+ # instance.
+ for msg in reversed(inst.parse_error_msgs):
+ _add_error_msg(exc, msg.text, msg.text_location)
+
+ raise
# Insert bytes into `self._data`
self._data[inst.offset_in_data : inst.offset_in_data + len(data)] = data
)
-# Parses the command-line arguments.
+# Raises a command-line error with the message `msg`.
+def _raise_cli_error(msg: str) -> NoReturn:
+ raise RuntimeError("Command-line error: {}".format(msg))
+
+
+# Returns a dictionary of string to integers from the list of strings
+# `args` containing `NAME=VAL` entries.
+def _dict_from_arg(args: Optional[List[str]]):
+ d = {} # type: LabelsT
+
+ if args is None:
+ return d
+
+ for arg in args:
+ m = re.match(r"({})=(\d+)$".format(_py_name_pat.pattern), arg)
+
+ if m is None:
+ _raise_cli_error("Invalid assignment {}".format(arg))
+
+ d[m.group(1)] = int(m.group(2))
+
+ return d
+
+
+# Parses the command-line arguments and returns, in this order:
+#
+# 1. The input file path, or `None` if none.
+# 2. The Normand input text.
+# 3. The initial offset.
+# 4. The initial byte order.
+# 5. The initial variables.
+# 6. The initial labels.
def _parse_cli_args():
import argparse
)
# Parse
- return ap.parse_args()
-
-
-# Raises a command-line error with the message `msg`.
-def _raise_cli_error(msg: str) -> NoReturn:
- raise RuntimeError("Command-line error: {}".format(msg))
-
-
-# Returns a dictionary of string to integers from the list of strings
-# `args` containing `NAME=VAL` entries.
-def _dict_from_arg(args: Optional[List[str]]):
- d = {} # type: LabelsT
-
- if args is None:
- return d
-
- for arg in args:
- m = re.match(r"({})=(\d+)$".format(_py_name_pat.pattern), arg)
-
- if m is None:
- _raise_cli_error("Invalid assignment {}".format(arg))
-
- d[m.group(1)] = int(m.group(2))
-
- return d
-
-
-# CLI entry point without exception handling.
-def _try_run_cli():
- import os.path
-
- # Parse arguments
- args = _parse_cli_args()
+ args = ap.parse_args()
# Read input
if args.path is None:
assert args.byte_order == "le"
bo = ByteOrder.LE
- # Parse
- try:
- res = parse(normand, variables, labels, args.offset, bo)
- except ParseError as exc:
- prefix = ""
+ # Return input and initial state
+ return args.path, normand, args.offset, bo, variables, labels
- if args.path is not None:
- prefix = "{}:".format(os.path.abspath(args.path))
-
- _fail(
- "{}{}:{} - {}".format(
- prefix, exc.text_loc.line_no, exc.text_loc.col_no, str(exc)
- )
- )
- # Print
- sys.stdout.buffer.write(res.data)
+# CLI entry point without exception handling.
+def _run_cli_with_args(
+ normand: str,
+ offset: int,
+ bo: Optional[ByteOrder],
+ variables: VariablesT,
+ labels: LabelsT,
+):
+ sys.stdout.buffer.write(parse(normand, variables, labels, offset, bo).data)
# Prints the exception message `msg` and exits with status 1.
if not msg.endswith("."):
msg += "."
- print(msg, file=sys.stderr)
+ print(msg.strip(), file=sys.stderr)
sys.exit(1)
# CLI entry point.
def _run_cli():
try:
- _try_run_cli()
+ args = _parse_cli_args()
+ except Exception as exc:
+ _fail(str(exc))
+
+ try:
+ _run_cli_with_args(*args[1:])
+ except ParseError as exc:
+ import os.path
+
+ prefix = "" if args[0] is None else "{}:".format(os.path.abspath(args[0]))
+ fail_msg = ""
+
+ for msg in reversed(exc.messages):
+ fail_msg += "{}{}:{} - {}".format(
+ prefix,
+ msg.text_location.line_no,
+ msg.text_location.col_no,
+ msg.text,
+ )
+
+ if fail_msg[-1] not in ".:;":
+ fail_msg += "."
+
+ fail_msg += "\n"
+
+ _fail(fail_msg.strip())
except Exception as exc:
_fail(str(exc))
projects / normand.git / commitdiff
