Add test for max_level()

Author: borntyping

src/lib.rs

@@ -608,6 +608,12 @@ mod test {
         assert!(logger.enabled(&create_log("chatty_dependency::module", Level::Warn)));
     }
 
+    #[test]
+    fn test_max_level() {
+        let builder = SimpleLogger::new();
+        assert_eq!(builder.max_level(), LevelFilter::Trace);
+    }
+
     #[test]
     #[cfg(feature = "timestamps")]
     fn test_timestamps_defaults() {