Always preload if using proc with multifetch cache#44616
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rails#31250 optimised rendering a collection with `cached: true`, but also with `cached: proc {}`. The problem is the proc may reference associations that should be preloaded to avoid n+1s in generating the cache key. For example: ```ruby @posts = Post.preload(:author) @view.render partial: "test/partial", collection: @post, cached: proc { |post| [post, post.author] } ``` This will n+1 on `post.author`. To fix this, this PR will always preload the collection if there's a proc given for `cached`. `cached: true` will still not preload unless it renders, as it did in rails#31250.
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#31250 optimised rendering a collection with
cached: true, but also when using a proc:cached: proc {}. The problem is the proc may reference associations that should be preloaded to avoid n+1s in generating the cache key.For example:
Since #31250, this will perform n+1 queries on
post.author.preload(:author)is never executed.To fix this, this PR will always preload the collection if there's a proc given for
cached.cached: truewill still not preload unless it renders, as it did in #31250.