Each collection.getAllSorted uses the same result object, needs to be a copy

[zachleat]

https://www.11ty.io/docs/collections/#getallsorted() and maybe other methods too, needs to be looked at.

Most of the time this might be okay (maybe? No one has noticed this but me 😅) but this is super intuitive when you use Array methods that perform operations in place, like .reverse(), it can give you unreliable results when you use it in two different calls.

Notably: the following will return two different results even though the code is the same 😭

eleventyConfig.addCollection("myPostsReverse", function(collection) {
  return collection.getAllSorted().reverse();
});
eleventyConfig.addCollection("myOtherPostsReverse", function(collection) {
  return collection.getAllSorted().reverse();
});

Workaround for now is to create a copy of your results like so:

eleventyConfig.addCollection("myPostsReverse", function(collection) {
  return collection.getAllSorted().slice(0).reverse();
});

The obvious fix here is to do this by default in the getAllSorted method.

[zachleat]

I lied, this was fixed awhile back in e4435f6

at https://github.com/11ty/eleventy/blob/master/src/Util/Sortable.js#L36 and https://github.com/11ty/eleventy/blob/master/src/TemplateCollection.js#L17

any calls to sort return a new array.