better tests

subject_source/tests/option.rs

@@ -1,15 +1,27 @@
 use subject_source::errors::option as opt;
 
 #[test]
-pub fn is_some() {
+pub fn is_some_none() {
     assert!(!opt::is_some(&None));
+}
+
+#[test]
+pub fn is_some_some() {
     assert!(opt::is_some(&Some(0)));
 }
 
 #[test]
-pub fn get_or_default() {
+pub fn get_or_default_none() {
     assert_eq!(opt::get_or_default(None, 1), 1);
+}
+
+#[test]
+pub fn get_or_default_some_same() {
     assert_eq!(opt::get_or_default(Some(1), 1), 1);
+}
+
+#[test]
+pub fn get_or_default_some_diff() {
     assert_eq!(opt::get_or_default(Some(2), 1), 2);
 }