What happened?

Description

It appears that this change is a breaking change in UrlHelper::isAbsoluteUrl()

In Craft 3/4, the following code:

        Craft::dd(UrlHelper::isAbsoluteUrl('C:\Users\joshcrawford\public_html\formie-craft5\vendor\verbb\formie\src\web\assets\forms\dist\manifest.json'));

...properly returns false

However on Craft 5 after the above change to UrlHelper::isAbsoluteUrl():

        Craft::dd(UrlHelper::isAbsoluteUrl('C:\Users\joshcrawford\public_html\formie-craft5\vendor\verbb\formie\src\web\assets\forms\dist\manifest.json'));

...returns true

Which I think is likely objectively wrong?

Yes, I know it's a file path that we're passing in, but in my case the param could be a URL or it could be a path, and I'm using UrlHelper::isAbsoluteUrl() to determine whether it's a fully qualified absolute URL, and if not, we assume it's a file path by the time we get there.

The change was made to fix #14830 but perhaps special-casing for mailto: or rejecting anything that begins with a capital letter and a colon would be less behavior braking?

I realize that arguably I should be testing to see whether it is a URL at all before passing it in to UrlHelper::isAbsoluteUrl() but I looked at the code for that function at the time, and figured it'd be as good of a way as any to determine whether it's a URL or path.

Even if I should not be using UrlHelper::isAbsoluteUrl() with a path to determine if it's an absolute URL, I'm not sure the current behavior should break?

Related issue: nystudio107/craft-plugin-vite#25

Steps to reproduce

1. Try using UrlHelper::isAbsoluteUrl() with a Window file path such as:

'C:\Users\joshcrawford\public_html\formie-craft5\vendor\verbb\formie\src\web\assets\forms\dist\manifest.json'

Expected behavior

It would return false for a Windows file system path

Actual behavior

It returns true

Craft CMS version

Craft 5

PHP version

n/a

Operating system and version

n/a

Database type and version

n/a

Image driver and version

n/a

Installed plugins and versions

• Vite plugin
• Any plugin that depends on craft-plugin-vite such as Formie, SEOmatic, Retour, etc.