Test: SquashFS required (clear error), check names of data/ files (error-filename)

[probonopd]

SquashFS only (error-not-squashfs)

• README: an AppImage must use SquashFS; DwarFS and others (e.g. from uruntime or quick-sharun) are not supported yet (see Add Mosaic Mod Manager #3868).
• Mount detection: the test used to take the last mount with "tmp" in it as the AppImage's contents. When the mount failed, that was an unrelated mount (/run/snapd/ns), and the test reported "AppRun is missing" there. It now waits for the mount of this AppImage, and if none appears, it prints the runtime's own message and ERROR: Could not mount the AppImage…. This gets the new label error-not-squashfs and a hint.
• Runtime output: the runtime's output now goes to a file instead of /dev/null, so its message is not lost.

Names of files in data/ (error-filename)

code/check-name.sh has rules derived from the ~1700 existing names. They are errors for files a PR adds, and warnings for existing entries, which may have older names:

Rule	Result
blanks (use _)	error
name of an AppImage file (.AppImage, x86_64, amd64, …)	error
"AppImage" or "Linux", unless part of the application's name in its desktop file	error
file extensions (.md, .txt, .yml, …)	error
existing entry with the same name in different capitalization	error
version numbers (numbers can be part of a name, e.g. Play_2048)	warning
unusual characters (EiskaltDC++, fre:ac)	warning
name does not match the application's name (82 existing entries, e.g. GIMP)	warning
"Linux" in the AppImage's own file name	warning

• Existing names under these rules: 22 would fail, all of them genuine: 7 case duplicates (e.g. digikam/digiKam), 5 file extensions, AppImage file names. 13 would get warnings.
• PR comment: shows the exact remarks under Names, accepting only lines of the known form.
• Label and README: new label error-filename; the README lists the rules.

Tested

On a throwaway PR (#3928, closed):

• a DwarFS AppImage → ERROR: Could not mount the AppImage…;
• data/Jorvik-linux-x86_64 → fails before downloading;
• data/Jorvik → passes, with no remarks.

Locally: check-name.sh on all existing names and on sample cases; shellcheck and actionlint are clean.

Hints, labels and the Names block in the comment take effect after merging (the publish workflow runs from master). The labels error-not-squashfs and error-filename already exist.

🤖 Generated with Claude Code

https://claude.ai/code/session_01DZvaN9tm5taf5avUvVtmyq

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Generated by Claude Code