display an error on malformed input

2 files changed, 17 insertions, 1 deletions

diff --git a/todolist/app.go b/todolist/app.go
index 24ebe4d..6d771ef 100644
--- a/todolist/app.go
+++ b/todolist/app.go
@@ -91,6 +91,18 @@ func (a *App) UnarchiveTodo(input string) {
 	fmt.Println("Todo unarchived.")
 }
 
+func (a *App) EditTodoSubject(input string) {
+	a.Load()
+	_, id, subject := Parser{input}.Parse()
+	id, todo := a.getId(input)
+	if id == -1 {
+		return
+	}
+	todo.Subject = subject
+	a.Save()
+	fmt.Println("Todo subject updated.")
+}
+
 func (a *App) EditTodoDue(input string) {
 	a.Load()
 	id, todo := a.getId(input)
diff --git a/todolist/parser.go b/todolist/parser.go
index d55ab3b..38bdb7f 100644
--- a/todolist/parser.go
+++ b/todolist/parser.go
@@ -34,10 +34,14 @@ func (p Parser) Parse() (string, int, string) {
 	input := p.input
 	r := regexp.MustCompile(`(\w+) (\d+) (.*)`)
 	matches := r.FindStringSubmatch(input)
+	if len(matches) < 4 {
+		fmt.Println("Could match command, id or subject")
+		return "", -1, input
+	}
 	id, err := strconv.Atoi(matches[2])
 	if err != nil {
 		fmt.Println("Invalid id.")
-		id = -1
+		return "", -1, input
 	}
 
 	return matches[1], id, matches[3]