test: verify immutability of views on the context

Author: Pfeil

src/test/java/edu/kit/datamanager/ro_crate/context/ContextTest.java

@@ -261,6 +261,8 @@ void testReadKeys() {
     for (String key : expected) {
       assertTrue(given.contains(key), "Key " + key + " not found in the context");
     }
+    // prove immutability
+    assertThrows(UnsupportedOperationException.class, () -> given.add("newKey"));
   }
 
   @Test
@@ -273,5 +275,7 @@ void testReadPairs() {
       assertTrue(keys.contains(key), "Key " + key + " not found in the context");
       values.forEach(s -> assertFalse(s.isEmpty(), "Value for key " + key + " is empty"));
     }
+    // prove immutability
+    assertThrows(UnsupportedOperationException.class, () -> given.put("newKey", "newValue"));
   }
 }

src/test/java/edu/kit/datamanager/ro_crate/crate/TestRemoveAddContext.java

@@ -62,6 +62,8 @@ void testReadContextKeys() {
     for (String key : expected) {
         assertTrue(given.contains(key), "Key " + key + " not found in the context");
     }
+    // prove immutability
+    assertThrows(UnsupportedOperationException.class, () -> given.add("newKey"));
   }
 
   @Test
@@ -74,5 +76,7 @@ void testReadContextPairs() {
         assertTrue(keys.contains(key), "Key " + key + " not found in the context");
         values.forEach(s -> assertFalse(s.isEmpty(), "Value for key " + key + " is empty"));
     }
+    // prove immutability
+    assertThrows(UnsupportedOperationException.class, () -> given.put("newKey", "newValue"));
   }
 }