What do you think about adding an option indentChains optional/always/never?

Depending on your settings one of these might error.

something()
.one()
.two()

something()(
    .one()
    .two()

I think optional/always/never may be a bit confusing. Does optional mean it does not care how you indent or just mean indenting properly is optional, and does never mean it never enforces indenting or that you should never indent?

For example if spacing was 2 and you set indentChain to 'optional' what does this return?

testa.b()
     .c()
     .d()

The user has indented to line the dots up with the rest of the chain. Does this violate an 'optional' lint?

I think there is essentially 4 types we have to worry about. Assuming indent spacing value is .

• People who want strict enforcement of indents (indenting can only be indented exactly X from previous line, no more, no less)
• People who want loose enforcement of indents (indenting can be a multiple of X from the previous line, I believe this is currently how the code for this PR handles indenting)
• People who want no enforcement of indentation (so they could do something like my code example above, this is currently how the code in coffeelint handles indents in chains)
• People who want to enforce no indenting in chains. (Your first code example)

There are probably a couple more styles people will have to deal with, but I think after this people should just write their own rule to enforce it.

I think personally I would go with strict, loose, none, and no_indents/no_indents_allowed(?) for these four types.

Also worried that maybe having too many options will add more complexity of the rule...

I was only thinking of two styles, you either indent your chain the same way you indent a function or you don't. With optional it doesn't care either way, which seems to be the current behavior.

That's a good point about complexity. I'll just merge this as is and if someone wants to enforce one of those indention styles maybe it can be its own rule. I really don't think this already complex rule needs 4 more variations.