Extract function for calling mktemp

BSD mktemp doesn't support GNU mktemp's -t or --tmpdir option, so when
we want a named temporary file, we need to compute ${TMPDIR:-/tmp}
ourselves, see 5accc7c6c5 (Fix funced's tmpfile generation on OSX,
2016-05-23).

While at it, use template like "fish.XXXXXX"; seems like a good idea?

Take care to have edit_command_buffer use a pretty filename.

share/completions/scp.fish

@@ -47,7 +47,7 @@ complete -c scp -d "Local Path" -n "not string match @ -- (commandline -ct)"
 complete -c scp -d "Remote Path" -f -n "commandline -ct | string match -e ':'" -a '
     (__scp_remote_target):(
         if not set -q __fish_scp_sftp
-            set -l tmp (mktemp)
+            set -l tmp (__fish_mktemp fish-scp)
             if scp -P(__scp2ssh_port_number) -o "BatchMode yes" -q -O $tmp (__scp_remote_target):/dev/null
                 set -g __fish_scp_sftp true
             else

share/functions/__fish_mktemp_relative.fish

@@ -0,0 +1,22 @@
+function __fish_mktemp_relative
+    # OSX mktemp is rather restricted - no suffix, no way to automatically use TMPDIR
+    if not set -q TMPDIR[1]
+        set -f TMPDIR /tmp
+    end
+    # TODO use "argparse --move-unknown"
+    set -l mktemp_args
+    set -l found_positional false
+    for arg in $argv
+        switch $arg
+            case '-*'
+                set -a mktemp_args $arg
+            case '*'
+                set -a mktemp_args $TMPDIR/$arg.XXXXXX
+                set found_positional true
+        end
+    end
+    if not $found_positional
+        set -a mktemp_args $TMPDIR/fish.XXXXXX
+    end
+    mktemp $mktemp_args
+end

share/functions/edit_command_buffer.fish

@@ -1,9 +1,9 @@
 function edit_command_buffer --description 'Edit the command buffer in an external editor'
-    set -l f (mktemp)
+    set -l tmpdir (__fish_mktemp_relative -d fish)
     or return 1
-    if set -q f[1]
+    set -l f
-        command mv $f $f.fish
+    if set -q tmpdir[1]
-        set f $f.fish
+        set f $tmpdir/command-line.fish
     else
         # We should never execute this block but better to be paranoid.
         if set -q TMPDIR
@@ -11,9 +11,9 @@ function edit_command_buffer --description 'Edit the command buffer in an extern
         else
             set f /tmp/fish.$fish_pid.fish
         end
-        command touch $f
-        or return 1
     end
+    command touch $f
+    or return 1
 
     set -l editor (__fish_anyeditor)
     or return 1
@@ -52,13 +52,13 @@ function edit_command_buffer --description 'Edit the command buffer in an extern
                     set found true
                     break
                 end
-                set cursor_from_editor (mktemp)
+                set cursor_from_editor (__fish_mktemp_relative fish-edit_command_buffer)
                 set -a editor +$line "+norm! $col|" $f \
                     '+au VimLeave * ++once call writefile([printf("%s %s %s", shellescape(bufname()), line("."), col("."))], "'$cursor_from_editor'")'
             case emacs emacsclient gedit
                 set -a editor +$line:$col $f
             case kak
-                set cursor_from_editor (mktemp)
+                set cursor_from_editor (__fish_mktemp_relative fish-edit_command_buffer)
                 set -a editor +$line:$col $f -e "
                         hook -always -once global ClientClose %val{client} %{
                             echo -to-file $cursor_from_editor -quoting shell \
@@ -117,7 +117,7 @@ function edit_command_buffer --description 'Edit the command buffer in an extern
         end
         command rm $cursor_from_editor
     end
-    command rm $f
+    command rm -r (path dirname $f)
     # We've probably opened something that messed with the screen.
     # A repaint seems in order.
     commandline -f repaint

share/functions/fish_config.fish

@@ -26,7 +26,7 @@ function fish_config --description "Launch fish's web based configuration"
                     echo "Cannot find web configuration tool. Please check your fish installation."
                     return 1
                 end
-                set -l temp (mktemp -d)
+                set -l temp (__fish_mktemp_relative -d fish_config)
                 for dir in (status list-files tools/web_config | path dirname | path sort -u)
                     mkdir -p $temp/$dir
                     or return

share/functions/fish_update_completions.fish

@@ -11,7 +11,7 @@ function fish_update_completions --description "Update man-page based completion
             echo "Cannot find man page completion generator. Please check your fish installation."
             return 1
         end
-        set -l temp (mktemp -d)
+        set -l temp (__fish_mktemp_relative -d fish_update_completions)
         for file in create_manpage_completions.py deroff.py
             status get-file tools/$file >$temp/$file
             or return

share/functions/funced.fish

@@ -58,12 +58,9 @@ function funced --description 'Edit function definition'
         return 0
     end
 
-    # OS X (macOS) `mktemp` is rather restricted - no suffix, no way to automatically use TMPDIR.
+    # Create a directory so we can use a ".fish" suffix for the file -
-    # Create a directory so we can use a ".fish" suffix for the file - makes editors pick up that
+    # makes editors pick up that it's a fish file.
-    # it's a fish file.
+    set -l tmpdir (__fish_mktemp_relative -d fish-funced)
-    set -q TMPDIR
-    or set -l TMPDIR /tmp
-    set -l tmpdir (mktemp -d $TMPDIR/fish.XXXXXX)
     or return 1
     set -l tmpname $tmpdir/$funcname.fish
 

share/functions/help.fish

@@ -226,9 +226,7 @@ function help --description 'Show help for the fish shell'
         # trampoline (they're only needed if there's a fragment in the path)
         if set -l clean_url (string match -re '#' $page_url)
             # Write a temporary file that will redirect where we want.
-            set -q TMPDIR
+            set -l tmpdir (__fish_mktemp_relative -d fish-help)
-            or set -l TMPDIR /tmp
-            set -l tmpdir (mktemp -d $TMPDIR/help.XXXXXX)
             or return 1
             set -l tmpname $tmpdir/help.html
             echo '<meta http-equiv="refresh" content="0;URL=\''$clean_url'\'" />' >$tmpname

share/functions/psub.fish

@@ -17,15 +17,11 @@ function psub --description "Read from stdin into a file and output the filename
         return 1
     end
 
-    set -l tmpdir /tmp
-    set -q TMPDIR
-    and set tmpdir $TMPDIR
-
     if set -q _flag_fifo
         # Write output to pipe. This needs to be done in the background so
         # that the command substitution exits without needing to wait for
         # all the commands to exit.
-        set dirname (mktemp -d $tmpdir/.psub.XXXXXXXXXX)
+        set dirname (__fish_mktemp_relative -d .psub)
         or return 1
         set filename $dirname/psub.fifo"$_flag_suffix"
         command mkfifo $filename
@@ -34,11 +30,11 @@ function psub --description "Read from stdin into a file and output the filename
         # after the fork.
         command tee $filename >/dev/null &
     else if test -z "$_flag_suffix"
-        set filename (mktemp $tmpdir/.psub.XXXXXXXXXX)
+        set filename (__fish_mktemp_relative .psub)
         or return 1
         command cat >$filename
     else
-        set dirname (mktemp -d $tmpdir/.psub.XXXXXXXXXX)
+        set dirname (__fish_mktemp_relative -d .psub)
         or return 1
         set filename "$dirname/psub$_flag_suffix"
         command cat >$filename