Simplified check for done task.

Use simple comparison with slice of string (already used e.g. in _list()) instead of grep -c pipeline.

tests/t1500-do.sh

@@ -81,6 +81,6 @@ test_todo_session 'fail multiple do attempts' <<EOF
 TODO: 3 marked as done.
 
 >>> todo.sh -a do 3
-TODO: 3 is already marked done.
+3 is already marked done
 EOF
 test_done

tests/t1700-depri.sh

@@ -68,30 +68,4 @@ TODO: 2 deprioritized.
 TODO: 3 of 3 tasks shown
 EOF
 
-cat > todo.txt <<EOF
-(B) smell the uppercase Roses +flowers @outside
-(A) notice the sunflowers
-stop
-EOF
-test_todo_session 'depriority of unprioritized task' <<EOF
->>> todo.sh -p list
-2 (A) notice the sunflowers
-1 (B) smell the uppercase Roses +flowers @outside
-3 stop
---
-TODO: 3 of 3 tasks shown
-
->>> todo.sh depri 3 2
-TODO: 3 is not prioritized.
-2 notice the sunflowers
-TODO: 2 deprioritized.
-
->>> todo.sh -p list
-1 (B) smell the uppercase Roses +flowers @outside
-2 notice the sunflowers
-3 stop
---
-TODO: 3 of 3 tasks shown
-EOF
-
 test_done

todo.sh

@@ -921,7 +921,10 @@ case $action in
 	todo=$(sed "$item!d" "$TODO_FILE")
 	[ -z "$todo" ] && die "TODO: No task $item."
 
-	if sed "$item!d" "$TODO_FILE" | grep "^(.) " > /dev/null; then
+	sed -e $item"s/^(.) //" "$TODO_FILE" > /dev/null 2>&1
+
+	if [ "$?" -eq 0 ]; then
+	    #it's all good, continue
 	    sed -i.bak -e $item"s/^(.) //" "$TODO_FILE"
 	    if [ $TODOTXT_VERBOSE -gt 0 ]; then
 		NEWTODO=$(sed "$item!d" "$TODO_FILE")
@@ -929,7 +932,7 @@ case $action in
 		echo "TODO: $item deprioritized."
 	    fi
 	else
-	    echo "TODO: $item is not prioritized."
+	    die "$errmsg"
 	fi
     done
     ;;
@@ -950,7 +953,7 @@ case $action in
         [ -z "$todo" ] && die "TODO: No task $item."
 
         # Check if this item has already been done
-        if [ `echo $todo | grep -c "^x "` -eq 0 ] ; then
+        if [ "${todo:0:2}" != "x " ]; then
             now=`date '+%Y-%m-%d'`
             # remove priority once item is done
             sed -i.bak $item"s/^(.) //" "$TODO_FILE"
@@ -961,7 +964,7 @@ case $action in
                 echo "TODO: $item marked as done."
 	    fi
         else
-            echo "TODO: $item is already marked done."
+            echo "$item is already marked done"
         fi
     done