source_script: Use command for external commands

users might have functions in interactive shells shadowing system commands.

functions/source_script.fish

@@ -53,8 +53,8 @@ function source_script --description 'Source sh/csh file'
   if test "$ext"
     eval "exec $exe -c '$source $argv; exec fish'"
   else
-    set -l f1 (mktemp -t tmp.XXXXXXXXXX)
-    set -l f2 (mktemp -t tmp.XXXXXXXXXX)
+    set -l f1 (command mktemp -t tmp.XXXXXXXXXX)
+    set -l f2 (command mktemp -t tmp.XXXXXXXXXX)
     eval $exe -c "'env | sort > $f1; $source $argv; env | sort > $f2'"
 
     set -l filter "(^[^\+-]|^\+\+\+|^---|^[\+-]_|^[\+-]PIPESTATUS|^[\+-]COLUMNS)"
@@ -62,7 +62,7 @@ function source_script --description 'Source sh/csh file'
 
     set -l IFS '='
     set -l diffopts --old-line-format '-=%L' --new-line-format '+=%L' --unchanged-line-format ''
-    diff $diffopts $f1 $f2 | grep -vE $filter | while read -l state var value
+    command diff $diffopts $f1 $f2 | command grep -vE $filter | while read -l state var value
       switch $state$var
         case -PATH
         continue
@@ -75,23 +75,20 @@ function source_script --description 'Source sh/csh file'
                 echo "Unable to add '$pt' to \$PATH. Check existance."
                 continue
             end
-            #echo set -gx PATH $PATH $pt
             set -gx PATH $PATH $pt >  /dev/null
         end
 
         case '-*'
-        #echo unset $var
         set -e $var
 
         case '+*'
-        eval set -gx $var (echo $value | sed $pattern)
-        #echo Set $var to: (echo $value | sed $pattern)
+        eval set -gx $var (echo $value | command sed $pattern)
 
         case '*'
         echo Source error! Invalid case "'$state$var'"
       end
     end
 
-    rm $f1 $f2 > /dev/null
+    command rm $f1 $f2 > /dev/null
   end
 end