GDScript: Fix multiline and trailing comma for assert

[vonagam]

Fixed parsing of assert with multiline and/or trailing comma.

Fixes #66535.

[kleonc]

Why are the trailing commas allowed? It doesn't make any sense to me, I'd expect an error when there's a trailing comma.

[adamscott]

I agree, the trailing comma doesn't really make sense.

[vonagam]

I'm not sure I understand the surprise:

func method(a, b = 'c',) -> void:
  print(a, b,)

func _ready() -> void:
  method('a',)
  method('a', 'b',)
  print(['a',],)

Trailing commas and multi-line are supported by method calls and arrays. That's just make it behave consistent with those. What am I missing?

[adamscott]

@vnen Is this a bug or a feature?

[vonagam]

It is a feature. Search for "// Allow for trailing comma." comment in parser - parse_call, parse_signal, parse_enum, parse_function_signature, parse_array, parse_dictionary all have that comment for code that allows trailing comma.

The utility is visual consistency and smaller more relevant diffs/blame in git. So for example, you can write code like:

assert(
  condition,
)

And then later in a separate commit add an error message, that would be 1 line addition instead of addition of 2 lines and removal of 1.

[anvilfolk]

LGTM! :) Batch reviewing these smaller PRs to see if we get some momentum going, hehe :)

[vnen]

Looks good to me.

[akien-mga]

Thanks!