Add :fn/index as alias for :index in map syntax

[dgr]

The map syntax supports an :index key that operates similarly to the various :fn/* keywords.

Indeed, in impl/xpath.clj the clause multimethod has all the :fn/* keywords as method selectors as well as :index. This suggests that perhaps :fn/index should be added as an alias for :index and :index be deprecated.

If folks agree that this is the way to go, I can submit a PR.

[lread]

So nice to see you active and interested in Etaoin @dgr!

I had to refresh my brain on how this all works (@borkdude and I are not the original authors of Etaoin but volunteered to maintain the project under clj-commons). So the :fn/* is for map syntax queries.

I'm not sure why :index is not :fn/index. Maybe it did not feel like a function to the original author?

So, my question to you is, why do you want this change? Do you feel strongly about it?
Were you confused and thrown off by :index not being :fn/index?

[dgr]

I think it's just about consistency. It seems like the :fn/* keywords are there because other map keys other than :tag end up as attributes of the element that are searched for. I don't feel strongly about it one way or another if there is a good reason for it to be different. But again, deep in the code, it's handled exactly the same way when constructing xpath. For backward compatibility, I'd just add a duplicate method to the multimethod (with defmethods in imps/util.clj), that way existing code would continue to work.

If you look at the xpath, it's clear that :index is not handled the same way as other attributes.

etaoin.api> (query/expand driver {:tag :foo :attr "blah"})
["xpath" ".//foo[@attr=\"blah\"]"]
etaoin.api> (query/expand driver {:tag :foo :index 1})
["xpath" ".//foo[1]"]
etaoin.api> (query/expand driver {:tag :foo :fn/enabled true})
["xpath" ".//foo[@enabled=true()]"]
etaoin.api> (query/expand driver {:tag :foo :class "blah"})
["xpath" ".//foo[@class=\"blah\"]"]

[lread]

Thanks @dgr, adding a synonym sounds fine to me.

Probably no need to deprecate :index but docs could be updated to replace :index with :fn/index (and would not need to mention :index). Sound good?

[dgr]

That sounds fine to me. Do we need any more opinions before I create a PR, or should I just for it?

[lread]

Seems like a solid plan to me! Feel free to proceed with a PR!