[FileFormats.MPS] allow spaces in NAME row

[odow]

Closes #2145

[mlubin]

Is this a fixed format vs free format issue? Do we support fixed format?

[odow]

So far we haven't made an explicit distinction between free and fixed format. The goal has been to be permissive in what we read, and restrictive in what we write. So everything gets written in fixed format where possible (except if there are long variable names).

The NAME row is pretty underspecified amongst solvers. They generally just say it's NAME followed by the name. I don't know why I originally enforced no spaces.

[mlubin]

Sounds fine to allow spaces in names. More generally, IIRC there are cases where you really need to know that you're parsing a fixed format file. They occur only for very old benchmark files. QPSReader has an option to force fixed format.

[odow]

More generally, IIRC there are cases where you really need to know that you're parsing a fixed format file. They occur only for very old benchmark files. QPSReader has an option to force fixed format.

I've been waiting for someone to complain or ask for this, but they haven't yet. It's just a matter of changing this line:

MathOptInterface.jl/src/FileFormats/MPS/MPS.jl

Lines 1134 to 1135 in 0adae07

	# TODO: split into hard fields based on column indices.
	items = line_to_items(line)