Self-referencing components are an undocumented breaking change

[palant]

The template compiler behavior changed for the following case:

<template>
  <custom-component />
</template>

With Vue 2 this would always resolve custom-component via component registration. With Vue 3, if this file is named CustomComponent.vue (camel-cased version of the tag name) this is automatically considered a self-reference, regardless of the component registration. While this behavior is intentional judging from the source code, it actually caused an infinite recursion in my code because of an unintended self-reference. So it needs to be documented in “Migration from Vue 2” at the very least.

For reference, the relevant commit: vuejs/core@67d1aac

[skirtles-code]

There does seem to be an open discussion about how exactly this should work: vuejs/core#2827 (comment). See also vuejs/core#2821.

[skirtles-code]

This has been changed in 3.0.8. It should now be consistent with Vue 2. The name of the file is now only taken into account if all else fails.