Add new implementation of HasCommand

lib/common.go

@@ -50,6 +50,33 @@ func BuildURI(rawuri, rawpath string) string {
 	return u.String()
 }
 
+func HasCommand(s, prefix string) bool {
+	s = strings.TrimSpace(s)
+
+	if len(s) == 0 || len(prefix) == 0 {
+		return false
+	}
+
+	if !strings.HasPrefix(s, prefix) {
+		return false
+	}
+
+	// remove the command prefix
+	s = s[len(prefix):]
+
+	// multiple assignment trick
+	cmd, _ := func() (string, string) {
+		x := strings.SplitN(s, " ", 2)
+		if len(x) > 1 {
+			return x[0], x[1]
+		}
+
+		return x[0], ""
+	}()
+
+	return len(cmd) > 0
+}
+
 func ContainsCommand(s, prefix, cmd string) bool {
 	s = strings.TrimSpace(s)
 

lib/common_test.go

@@ -26,3 +26,30 @@ func TestContainsCommand(t *testing.T) {
 		}
 	}
 }
+
+func TestHasCommandCommand(t *testing.T) {
+	tables := []struct {
+		s      string
+		prefix string
+		want   bool
+	}{
+		{"!command", "!", true},
+		{"!command x y", "!", true},
+		{"!c x y", "!", true},
+		{"! x y", "!", false},
+		{"hey guy", "!", false},
+		{"hey", "!", false},
+		{"hey", "", false},
+		{"", "!", false},
+		{"", "", false},
+	}
+
+	for _, table := range tables {
+		if got, want := HasCommand(table.s, table.prefix), table.want; got != want {
+			t.Errorf(
+				"s: %s, prefix: %s, got: %t, want: %t",
+				table.s, table.prefix, got, want,
+			)
+		}
+	}
+}