Subject: bug#60186: 29.0.60; ruby-mode indentation of multi-line expressions

From: Dmitry Gutov <[email-masked]>
Date: Wed, 28 Dec 2022 14:47:12 +0200

On 28/12/2022 05:47, Aaron Jensen wrote:
> On Tue, Dec 27, 2022 at 8:02 PM Dmitry Gutov <[email-masked]> wrote:
>>
>> On 28/12/2022 02:38, Aaron Jensen wrote:
>>
>>>> Or here's a step back: looking at how the two other user options I named
>>>> previously were ruby-method-params-indent and ruby-block-indent, the
>>>> latest might as well be called ruby-operator-indent, or
>>>> ruby-operator-indent and ruby-method-call-indent.
>>>>
>>>> I wasn't too crazy about those names originally, but the approach is
>>>> very extensible with styles by adding new symbols as possible values.
>>>
>>> This may end up being the right direction. If the values are symbols
>>> you can use things that are relative to one another like "simple".
>>> There could be a benefit to all of these having a "simple" option.
>>> What would it mean if it were nil?
>>> What's the current behavior called?
>>
>> For the sake of uniformity, I wanted to start with simple values -- t
>> and nil, and explain their meanings in the docstring.
>>
>> 't' would mean the current behavior, and I'd call it "structural", or
>> structure-based indentation. Or based on implicit expression grouping.
> 
> I'd typically not use t and nil on anything but a boolean and the name
> would be named after what t represents, but this may be an Emacs idiom
> that is OK. If so, and there's no better options (i.e., going against
> that idiom is worse than not), then that works for me.

I guess that particular trend started with ruby-method-params-indent, 
where I haven't managed to choose better names for the var, or the values.

>>> It may be that if we only intend to support two indentation schemes we
>>> just have default and simplified as you suggested and then we can use
>>> boolean values. I don't know how Emacs-like this is, but what if there
>>> were one variable like `ruby-indent-simple` that could either be `t`
>>> or a list of things to indent simply?
>>
>> That can work too, but what is "simple"? ;-)
>>
>> Further, I'm not sure if we're going to get more than 2 "things" this
>> way (operators and method calls). OTOH, if we have a separate var for
>> operators -- ruby-operator-indent -- we could enumerate which operators
>> to indent "structurally" after. Or something like that.
>>
>> Not sure which direction the feature requests will drive this extension
>> toward, though. Maybe mostly nowhere, given the previous history. But
>> Rubocop's example seems to indicate that there are many different styles
>> out there.
> 
> Yeah, hard to say, and it may eventually become less important if
> ruby-ts comes about and has enough options to satisfy folks with
> different ideas about indentation.

ruby-ts-mode might have extra flexibility down the line, but at the 
start I want to have it obey the same indentation options as ruby-mode.

BTW, you can check out its progress at 
https://github.com/pedz/ruby-ts-mode/.