Feature: MIME Association Reader

Purpose

The project must answer “which application opens this file type, and where is that decision recorded?” by resolving a MIME type through the MIME Applications Specification.

Requirements

• MIME-ASSOCIATION-READER-R001 — The reader must search mimeapps.list in this order: $XDG_CONFIG_HOME, each $XDG_CONFIG_DIRS entry, $XDG_DATA_HOME/applications, each $XDG_DATA_DIRS entry plus /applications.
• MIME-ASSOCIATION-READER-R002 — The reader must consult the deprecated defaults.list only after every mimeapps.list.
• MIME-ASSOCIATION-READER-R003 — The reader must read [Default Applications], [Added Associations], and [Removed Associations].
• MIME-ASSOCIATION-READER-R004 — The reader must treat a [Removed Associations] entry as removing an ID at that precedence or lower.
• MIME-ASSOCIATION-READER-R005 — The reader must resolve a desktop file ID through the application search path, including the prefix-to-subdirectory mapping.
• MIME-ASSOCIATION-READER-R006 — The reader must fall back to mimeinfo.cache in the application directories when no explicit default is recorded, because that is what the desktop uses.
• MIME-ASSOCIATION-READER-R007 — The reader must report the winning desktop ID, its resolved path, the source file, and the group.
• MIME-ASSOCIATION-READER-R008 — The reader must report the ordered list of files it searched.
• MIME-ASSOCIATION-READER-R009 — The reader must skip a missing or unreadable file without error.
• MIME-ASSOCIATION-READER-R010 — The reader must not throw.

Behavior

• Given a default recorded in $XDG_CONFIG_HOME/mimeapps.list, that file is the reported source.
• Given a default whose desktop file is absent, the next ID in the same value is tried.
• Given no recorded default but a mimeinfo.cache association, the cache association is reported.
• The answer matches xdg-mime query default for the same type.

Dependencies

• None.