Fix Python 3.11+ incompatibility: size int-like instruction args as one byte

[HansGR]

On Python 3.11+, -ruin/door-rando seeds (and any build whose event
layout places a multi-bit IntFlag arg before a forward label) can fail at
the final ROM write with:

TypeError: 'NoneType' object cannot be interpreted as an integer

Root cause: Python 3.11 added __len__ to enum.IntFlag, which returns
the number of set flags (popcount) instead of raising TypeError. The
byte-counting helpers in memory/space.py size flattened values with
try: n += len(value) except: n += 1, relying on len() raising for
scalar byte values. Instruction args that are IntFlag members are int
subclasses representing a single byte, but on 3.11+ len() now returns
their popcount, e.g.:

len(Flash.WHITE)  # 0xE0, 3 bits -> 3   (was: TypeError -> counted as 1)
len(Flash.NONE)   # 0x00, 0 bits -> 0   (was: TypeError -> counted as 1)

Flash is an IntFlag and is passed straight through to FlashScreen, so
field.FlashScreen(field.Flash.WHITE) makes _parse_labels over-count the
byte offset by 2. Every subsequent label pointer in that block is then
written two bytes past its placeholder, leaving unresolved None bytes in
the ROM data that surface at bytearray(self.data). (IntEnum, e.g.
Status, is unaffected -- only IntFlag gained __len__.)

Fix: treat int instances (which include IntEnum/IntFlag) as a single
byte in the three byte-counting sites -- _parse_labels, clear, and the
Write size pre-pass -- so counts match the bytes actually emitted on every
interpreter. No behavior change on 3.10; 3.11 and 3.12 now produce output
identical to each other.

Repro of the underlying enum change (no game data needed):

python3.10 -c "from enum import IntFlag; \
  class F(IntFlag): A=0x80;B=0x40;C=0x20; \
  print(len(F.A|F.B|F.C))"   # TypeError
python3.11 -c "from enum import IntFlag; \
  class F(IntFlag): A=0x80;B=0x40;C=0x20; \
  print(len(F.A|F.B|F.C))"   # 3

https://claude.ai/code/session_01Tvbr7PfXazsR3SAPXUMKmc

[gemini-code-assist]

Code Review

This pull request updates memory/space.py to ensure compatibility with Python 3.11+, where IntFlag objects implement len() to return a popcount. By introducing explicit isinstance(value, int) checks, the code avoids incorrect length calculations for integer-like values. The review feedback recommends replacing a bare except: clause in the clear method with specific exception handling (TypeError and ZeroDivisionError) to prevent catching system-interrupting exceptions.

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[gemini-code-assist]

Avoid using a bare except: clause as it can catch unexpected exceptions like SystemExit or KeyboardInterrupt, making debugging harder and preventing proper program interruption. Since len(value) can raise a TypeError (if the object has no length) or ZeroDivisionError (if the length is zero), it is better to catch these specific exceptions explicitly.

Suggested change

	try:
	values = [value] * (len(self) // len(value))
	except:
	values = [value] * len(self)
	try:
	values = [value] * (len(self) // len(value))
	except (TypeError, ZeroDivisionError):
	values = [value] * len(self)

References

1. PEP 8 recommends avoiding bare except clauses because they catch SystemExit and KeyboardInterrupt exceptions, making it harder to interrupt a program with Control-C. ^(link)