Add reselect method

[willianveiga]

Allows you to change a previously set select statement:

Post.select(:title, :body).reselect(:created_at) # SELECT `posts.created_at` FROM `posts`

This is short-hand for unscope(:select).select(fields).

Note that we're unscoping the entire select statement.

def reselect(*fields)
  unscope(:select).select(*fields)
end

We already have rewhere and reorder. @brchristian said in #27340: "... I find it a helpful syntax to have, especially after getting used to the feel of the other two ..."

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[dillonwelch]

Never thought of that before but super cool idea. LGTM after a changelog entry! 👍

[willianveiga]

Never thought of that before but super cool idea. LGTM after a changelog entry!

Done, @oniofchaos. Thank you very much! 😄

[simi]

I think it will be great to mention this next to rewhere and reorder in ActiveRecord overriding conditions guides.

[willianveiga]

I've made it, @simi. Thank you very much! 😃

[dcangulo]

When will this get merged?

[dillonwelch]

Sadly there's a changelog merge conflict 😭

[willianveiga]

Sadly there's a changelog merge conflict

Not anymore! 😄

[g1938703]

What about now, @oniofchaos? When will it be merged?

[dillonwelch]

@g1938703 as I am not a maintainer I do not have merge capabilities. I am just helping out by providing reviews and commentary on PRs. It's ultimately up to that group, such as the assignee pixeltrix, when and if the PR gets merged.

Also, there's another merge conflict on the changelog :D

[willianveiga]

@oniofchaos, nice job helping people out! 😃

@pixeltrix, when will this get merged?

Thank you very much, guys!

[pixeltrix]

@willianveiga looking at the implementation for reorder and rewhere it seems to me that an implementation similar to reorder is more appropriate - unscope(:select).select(args) will create an extra relation instance compared to how reorder does it. The rewhere can't do it in the same way because it can redo a subset of conditions whereas reorder doesn't and reselect is the same.

[willianveiga]

Is that what you meant, @pixeltrix?

Thank you very much, Wilian.

[ericgulini]

When will it be merged? Thank you!

[bobbytables]

Is this ever going to be merged?

[pixeltrix]

@willianveiga thanks! 👍

[bogdanvlviv]

Would be great to move this changelog entry to the top of the file to point that this method will be available since the next Rails release.