Add Did+DidUrl toString() method test cases

Author: filip26

src/test/java/com/apicatalog/did/DidTest.java

@@ -55,6 +55,16 @@ void fromUri(String input, String method, String specificId) {
         assertEquals(specificId, did.getMethodSpecificId());
     }
 
+    @DisplayName("toString()")
+    @ParameterizedTest(name = "{0}")
+    @MethodSource({ "validVectors" })
+    void toString(String input, String method, String specificId) {
+        final Did did = Did.from(input);
+
+        assertNotNull(did);
+        assertEquals(input, did.toString());
+    }
+    
     @DisplayName("!from(URI)")
     @ParameterizedTest()
     @MethodSource({ "negativeVectors" })

src/test/java/com/apicatalog/did/DidUrlTest.java

@@ -71,6 +71,16 @@ void stringIsDid(String uri) {
     void uriIsDid(String uri) {
         assertTrue(DidUrl.isDidUrl(URI.create(uri)));
     }
+    
+    @DisplayName("toString()")
+    @ParameterizedTest(name = "{0}")
+    @MethodSource({ "validVectors" })
+    void toString(String input) {
+        final DidUrl didUrl = DidUrl.from(input);
+
+        assertNotNull(didUrl);
+        assertEquals(input, didUrl.toString());
+    }
 
     static Stream<String[]> validVectors() {
         return Arrays.stream(new String[][] {