git rev-parse argument are not files, no need to try to find abs-path

This was causing some error message on Windows

g

@@ -220,7 +220,11 @@ while shift ; do
                 exit 1
             }
         fi
-
+        if [ "$COMMAND" == "rev-parse" ] ; then
+            # this is not a file
+            FILES[$FILESNUM]="$PARAM"
+            FILESNUM=$(($FILESNUM+1))
+        else
             # make the paths absolute
             FILES[$FILESNUM]=$(perl -e 'use Cwd "abs_path"; print abs_path(shift);' "$PARAM")
             if [ -z "${FILES[$FILESNUM]}" -o ! -e "${FILES[$FILESNUM]}" ] ; then
@@ -229,6 +233,7 @@ while shift ; do
             fi
             FILESNUM=$(($FILESNUM+1))
        fi
+    fi
 done
 
 # do it!