brew Add appimage support for linux

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This adds support for the first linux-only cask stanza: app_image. We should probably add CI for Linux casks, but haven't been able to get that working yet.

Jul 30 '25 20:07 SMillerDev

We should probably add CI for Linux casks, but haven't been able to get that working yet.

Need CI before this PR is merged.

Where are the app images installed and is that an expected/sensible location?

Maybe we should reuse app for this on Linux (or is that too confusing)?

Jul 31 '25 09:07 MikeMcQuaid

Maybe we should reuse app for this on Linux

I considered it, but deemed it too confusing. Especially with it not working on macOS.

Where are the app images installed and is that an expected/sensible location?

In ~/Applications, their docs recommend it. https://docs.appimage.org/user-guide/faq.html#question-where-do-i-store-my-appimages

Jul 31 '25 09:07 SMillerDev

@SMillerDev sounds good 👍🏻

Jul 31 '25 11:07 MikeMcQuaid

I'm also considering adding a desktop file for these so the various Linux systems can pick it up easily.

Ref: https://specifications.freedesktop.org/desktop-entry-spec/latest/

Aug 01 '25 10:08 SMillerDev

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

Aug 23 '25 00:08 github-actions[bot]

This is waiting for the following pieces:

[ ] Adding integration tests to testbot so I don't break it again
[ ] Add cask change detection to testbot
[ ] Adding Linux CI to homebrew/cask

Aug 23 '25 06:08 SMillerDev

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

Sep 14 '25 00:09 github-actions[bot]

Not stale, but it is waiting for Linux CI for casks, and that's not going as fast as I'd like. So help would be much appreciated.

Sep 14 '25 08:09 SMillerDev

Okay, now that Linux CI for casks is merged I'm planning to:

[ ] make a PR that stops requiring --cask in Linux
[ ] Prepare this PR for review

Oct 05 '25 12:10 SMillerDev

I guess this is an implementation of https://github.com/Homebrew/brew/issues/15808

Oct 21 '25 15:10 SMillerDev

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

Nov 13 '25 00:11 github-actions[bot]

Planning to finish this after the 22nd when I'm back from holiday.

Nov 13 '25 05:11 SMillerDev

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

Dec 05 '25 00:12 github-actions[bot]