Add linter to detect scripts that should not be split over multiple lines

[himdel]

Hi,
if you have a multiline if statement in haml, for example:

- if false ||
-    true
    Wheee!

haml-lint outputs a bogus

foo.haml:1 [W] RuboCop: Syntax: unexpected token kEND

(In some cases it's $end instead of kEND.)

It's probably in RuboCop but since I can't figure out what actually gets passed to rubocop (the --debug output doesn't trigger it), I'm making an issue here.

Any thoughs please?

[sds]

I don't know if writing code this way always does what you want, and I would advise against it. I think haml-lint is actually doing the right thing here given the quick investigation I've done.

Consider the following code:

- if false ||
-    true
  Wheee!
- else
  Something else!

The above code fails to compile when run via haml itself:

haml test.haml
Syntax error on line 4: Got "else" with no preceding "if"

Why this works without the else is beyond the time I have to spare for this right now.

Just to drive the point home, consider another example:

= 1 +
= 2

Given your example above this should work, but it fails to compile. Spanning scripts across multiple lines doesn't do what you expect.

This does suggest we should add a linter for this situation, however. :)

[himdel]

Hi, I actually noticed the else problem with haml, and I obviously agree with your = 1 + counter-example, it's just that .. well, sometimes you really want to be able to do a multiline if, and the | haml operator doesn't seem to do the trick. But oh well, what can you do, back to rewriting.. :) I guess something like - tmp ||= subcondition might do the trick.

I do agree that there should be a linter since this is apparently not supported nor even mentioned in haml docs. Also, please note that code like - if foo || without any subsequent - line passes haml-lint checks as well.

[sds]

Quickly whipped together a solution that will probably catch most cases in 11ca42a.