Accept an insignificant comma where an array element would be - #238
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Accept an insignificant comma where an array element would be#238webdevred wants to merge 1 commit into
webdevred wants to merge 1 commit into
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BeamNG treats a comma as insignificant, so an array with a stray one where an element would be is a file the game reads. The grammar allows exactly one comma between elements and has nowhere to put a second, so the parse stops.
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Part of #230. A failing spec only, no fix yet, so it stays a draft until the question at the end is settled.
BeamNG treats a comma as insignificant, closer to whitespace than to structure. Stock files rely on that, and one of the shapes is a stray comma where an array element would be:
Our grammar allows exactly one comma between elements, and
separatorParserruns only between them, so a second one has nowhere to sit. The parse stops at it.The spec asserts only that the input is accepted. What the formatter writes back for the empty slot is a separate decision, and it needs its own spec once it is made. Two ways to go:
Drop it. The file means the same thing to the game, and the formatter already normalises whitespace, indentation and padding, so a comma carrying nothing falls in the same category.
collectElementsskips it and nothing else changes.Keep it.
ArrayValueholdsVector (Node, Bool)where the flag means "this element was followed by a comma", so a comma with no element has nowhere to live. Preserving it needs either a node that renders as nothing or a second field, andAutoPadderives column widths from the elements, so it would also have to learn that the slot is not a column.I lean towards dropping it.