Add tests for rational ops

Author: unageek

.github/workflows/build.yml

@@ -26,7 +26,7 @@ jobs:
         run: cargo test --release
 
       - name: Clippy
-        run: cargo clippy -- -Dwarnings
+        run: cargo clippy --all-targets -- -Dwarnings
 
       - name: Check format
         run: cargo fmt -- --check