fish-shell/share/functions/__fish_apropos.fish
Rebecca Turner a6c8cd6e85 Fix man completions on macOS with symlinked manpath
When `manpath` prints a symlink to a directory, `/usr/libexec/makewhatis`
ignores the entire directory:

```
$ /usr/libexec/makewhatis -o /tmp/whatis \
    (/usr/bin/manpath | string split :)
makewhatis: /Users/wiggles/.nix-profile/share/man: Not a directory
```

This means that the built-in `man` completions will not index any commands in
these directories.

If we pass the directories to `readlink -f` first, `makewhatis` correctly
indexes the `man` pages.

```
$ /usr/libexec/makewhatis -o /tmp/whatis \
    (/usr/bin/manpath | string split : | xargs readlink -f)
```
2024-09-14 13:38:33 -07:00

54 lines
1.8 KiB
Fish

if not type -q apropos
function __fish_apropos
end
exit
end
# Check for macOS Catalina or above. This is Darwin 19.x or above. See unames reported here:
# https://en.wikipedia.org/wiki/Darwin_(operating_system)
set -l sysver (uname -sr | string match -r "(Darwin) (\d\d)"\.)
if test $status -eq 0 -a (count $sysver) -eq 3
and test $sysver[2] = Darwin -a $sysver[3] -ge 19
and test -x /usr/libexec/makewhatis
set -l dir
if test -n "$XDG_CACHE_HOME"
set dir $XDG_CACHE_HOME/fish
else
set dir (getconf DARWIN_USER_CACHE_DIR)"fish"
end
function __fish_apropos -V dir
# macOS 10.15 "Catalina" has a read only filesystem where the whatis database should be.
# The whatis database is non-existent, so apropos tries (and fails) to create it every time,
# which can take seconds.
#
# Instead, we build a whatis database in the user cache directory
# and override the MANPATH using that directory before we run `apropos`
#
# the cache is rebuilt once a week.
set -l whatis $dir/whatis
set -l max_age 600000 # like a week
set -l age $max_age
if test -f "$whatis"
set age (path mtime -R -- $whatis)
end
MANPATH="$dir" apropos "$argv"
if test $age -ge $max_age
test -d "$dir" || mkdir -m 700 -p $dir
/usr/libexec/makewhatis -o "$whatis" (/usr/bin/manpath | string split : | xargs readlink -f) >/dev/null 2>&1 </dev/null &
disown $last_pid
end
end
else
function __fish_apropos
# we only ever prefix match for completions. This also ensures results for bare apropos <TAB>
# (apropos '' gives no results, but apropos '^' lists all manpages)
apropos "$argv"
end
end