Add tests to `get_file_list`.

src/main.rs

@@ -134,3 +134,19 @@ fn full_name_test() {
 
     assert_eq!(replace_name(INPUT, PATTERN, REPLACEMENT), RESULT);
 }
+
+#[test]
+fn file_list_test() {
+    const DIRECTORY: &str = "src";
+    const WILDCARD: &str = "*.rs";
+
+    assert_eq!(get_file_list(DIRECTORY, WILDCARD), vec!["main.rs"]);
+}
+
+#[test]
+fn empty_file_list_test() {
+    const DIRECTORY: &str = "src";
+    const WILDCARD: &str = "*.exe";
+
+    assert_eq!(get_file_list(DIRECTORY, WILDCARD), Vec::<String>::new());
+}