Improve eopkg completions by using the --installed flag (#5089)

Utilized the `--install` flag added in commit #8c09d6e.

Limit `eopkg remove/autoremove/check ...` completions to installed packages.
Limit `eopkg install/upgrade/info ...` completions to available packages.

CHANGELOG.md

@@ -163,6 +163,7 @@ Xcode builds and macOS packages could not be produced with 2.7b1, but this is fi
   - `apt`
   - `cd` (#4061)
   - `composer` (#4295)
+  - `eopkg`
   - `flatpak` (#4456)
   - `git` (#4117, #4147, #4329, #4368)
   - `gphoto2`

share/completions/eopkg.fish

@@ -39,7 +39,8 @@ end
 
 # Setup additional completion
 complete -f -c eopkg -n '__fish_seen_subcommand_from remove-repo rr enable-repo er disable-repo dr list-available la' -a "(__fish_eopkg_print_repos)" -d "Repository"
-complete -f -c eopkg -n '__fish_seen_subcommand_from upgrade up remove rm autoremove rmf install it info check' -a "(__fish_print_packages)" -d "Package"
+complete -f -c eopkg -n '__fish_seen_subcommand_from upgrade up install it info' -a "(__fish_print_packages)" -d "Available Package"
+complete -f -c eopkg -n '__fish_seen_subcommand_from remove rm autoremove rmf check' -a "(__fish_print_packages --installed)" -d "Installed Package"
 complete -f -c eopkg -n '__fish_seen_subcommand_from upgrade up remove rm install it info check list-available la list-installed li list-upgrades lu' -s c -l component -a "(__fish_eopkg_print_components)" -d "Component"
 
 # Setup eopkg subcommand with shortcut

share/functions/__fish_print_packages.fish

@@ -145,8 +145,24 @@ function __fish_print_packages
     if type -q -f eopkg
 
         # If the cache is less than max_age, we do not recalculate it
+        # Determine whether to print installed/available packages
 
-        set cache_file $XDG_CACHE_HOME/.eopkg-cache.$USER
+        if set -q only_installed
+            set cache_file $XDG_CACHE_HOME/.eopkg-installed-cache.$USER
+            if test -f $cache_file
+                cat $cache_file
+                set age (math (date +%s) - (stat -c '%Y' $cache_file))
+                set max_age 500
+                if test $age -lt $max_age
+                    return
+                end
+            end
+
+            # Remove package version information from output and pipe into cache file
+            eopkg list-installed -N | cut -d ' ' -f 1 >$cache_file &
+            return
+        else
+            set cache_file $XDG_CACHE_HOME/.eopkg-available-cache.$USER
             if test -f $cache_file
                 cat $cache_file
                 set age (math (date +%s) - (stat -c '%Y' $cache_file))
@@ -160,6 +176,7 @@ function __fish_print_packages
             eopkg list-available -N | cut -d ' ' -f 1 >$cache_file &
             return
         end
+    end
 
     # This completes the package name from the portage tree.
     # True for installing new packages. Function for printing