Wrapping of concatenated string literals

[Gama11]

Describe the bug

Another one from the vshaxe diff since 1.7.1:

Input file

class Main {
	static function main() {
		context.sendShowMessage(Error, 'Invalid compiler argument \'$option\' detected. '
			+ 'Please verify "haxe.configurations" and "haxe.displayServer.arguments".');
	}
}

Broken output

class Main {
	static function main() {
		context.sendShowMessage(Error,
			'Invalid compiler argument \'$option\' detected. ' + 'Please verify "haxe.configurations" and "haxe.displayServer.arguments".');
	}
}

Not sure if this is technically a bug, but the wrapping in the "before" snippet makes a lot more sense to me.

[AlexHaxe]

There are two wrapping rules that could apply to that line: call parameter and OpAdd chain, for now the first one wins.

Wrapping code currently doesn't have a weighting function or even a way to preview or play with different combinations of wrapping rules.

Creating a weighting function involves figuring out how to score different wrapping outcomes, so that "before" has a higher score than "broken".

[Gama11]

Should a single + already count as an OpAdd "chain"?

[AlexHaxe]

Well, + already implies two items.
And despite it being a valid OpAdd chain or not, wrapping at + and wrapping at , both produce a valid output below max line length.
So either way there needs to be some scoring for formatter to decide which wrapping to apply on a particular line that has two or more competing wrapping rules.