improve make target completion

- Support completing dynamic make targets.
- Support completing make targets when using -C/--directory.
- Support `-Cdir/path`, `-C dir/path`
- Support `--directory=dir/path`, `--directory dir/path`

This detects if the make command have the `-p` switch otherwise it
assumes it is BSD make and will run a different command to try to figure
out the available targets.

share/completions/make.fish

@@ -1,13 +1,21 @@
 # Completions for make
+function __fish_complete_make_targets
+    set directory (string replace -r '^make .*(-C ?|--directory[= ]?)([^ ]*) .*$' '$2' -- $argv)
+    if test $status -eq 0 -a -d $directory
+        __fish_print_make_targets $directory
+    else
+        __fish_print_make_targets
+    end
+end
 
 # This completion reenables file completion on
 # assignments, so e.g. 'make foo FILES=<tab>' will receive standard
 # filename completion.
 complete -c make -n 'commandline -ct | string match "*=*"'
 
-complete -x -c make -a "(__fish_print_make_targets)" --description "Target"
+complete -x -c make -a "(__fish_complete_make_targets (commandline -c))" --description "Target"
 complete -r -c make -s f --description "Use file as makefile" -r
-complete -x -c make -s C -x -a "(__fish_complete_directories (commandline -ct))" --description "Change directory"
+complete -x -c make -s C -l directory -x -a "(__fish_complete_directories (commandline -ct))" --description "Change directory"
 complete -c make -s d --description "Debug mode"
 complete -c make -s e --description "Environment before makefile"
 complete -c make -s i --description "Ignore errors"

share/functions/__fish_print_make_targets.fish

@@ -1,13 +1,26 @@
-function __fish_print_make_targets
-    # Some seds (e.g. on Mac OS X), don't support \n in the RHS
-    # Use a literal newline instead
-    # http://sed.sourceforge.net/sedfaq4.html#s4.1
-    # The 'rev | cut | rev' trick removes everything after the last colon
-    for file in GNUmakefile Makefile makefile
+function __fish_print_make_targets --argument directory
+    # Since we filter based on localized text, we need to ensure the
+    # text will be using the correct locale.
+    set -lx LC_ALL C
+
+    if test -z "$directory"
+        set directory '.'
+    end
+
+    set -l bsd_make
+    if make -C $directory -pn >/dev/null ^/dev/null
+        set bsd_make 0
+    else
+        set bsd_make 1
+    end
+
+    for file in $directory/{GNUmakefile,Makefile,makefile}
         if test -f $file
-            __fish_sgrep -h -o -E '^[^#%=$[:space:]][^#%=$]*:([^=]|$)' $file ^/dev/null | rev | cut -d ":" -f 2- | rev | sed -e 's/^ *//;s/ *$//;s/  */\\
-/g' ^/dev/null
-            # On case insensitive filesystems, Makefile and makefile are the same; stop now so we don't double-print 
+            if test "$bsd_make" = 0
+                make -C $directory -prRn | awk -v RS= -F: '/^# Files/,/^# Finished Make data base/ {if ($1 !~ "^[#.]") {print $1}}' ^/dev/null
+            else
+                make -C $directory -d g1 -rn >/dev/null ^| awk -F, '/^#\*\*\* Input graph:/,/^$/ {if ($1 !~ "^#... ") {gsub(/# /,"",$1); print $1}}' ^/dev/null
+            end
             break
         end
     end