/usr/share/fish/completions/apt-file.fish is in fish-common 2.2.0-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 | #apt-file
complete -c apt-file -s h -l help --description "Display help and exit"
complete -x -c apt-file -a update --description "Resync package contents from source"
complete -r -c apt-file -a search --description "Search package containing pattern"
complete -r -c apt-file -a list --description "List contents of a package matching pattern"
complete -x -c apt-file -a purge --description "Remove all gz files from cache"
complete -r -c apt-file -s c -l cache --description "Set cache dir"
complete -f -c apt-file -s v -l verbose --description "Verbose mode"
complete -c apt-file -s d -l cdrom-mount --description "Use cdrom-mount-point"
complete -f -c apt-file -s i -l ignore-case --description "Do not expand pattern"
complete -f -c apt-file -s x -l regexp --description "Pattern is regexp"
complete -f -c apt-file -s V -l version --description "Display version and exit"
complete -f -c apt-file -s a -l architecture --description "Set arch"
complete -r -c apt-file -s s -l sources-list -a "(ls /etc/apt)" --description "Set sources.list file"
complete -f -c apt-file -s l -l package-only --description "Only display package name"
complete -f -c apt-file -s F -l fixed-string --description "Do not expand pattern"
complete -f -c apt-file -s y -l dummy --description "Run in dummy mode"
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