### Question:
BaseProvider { public Set<String> getPropertyIds() { return propertyIds; } BaseProvider(Set<String> propertyIds); Set<String> checkPropertyIds(Set<String> propertyIds); Set<String> getPropertyIds(); Set<String> getCategoryIds();  }### Answer:
@Test public void testGetProperties() { Set<String> propertyIds = new HashSet<>(); propertyIds.add("foo"); propertyIds.add("bar"); propertyIds.add("cat1/prop1"); propertyIds.add("cat2/prop2"); propertyIds.add("cat3/subcat3/prop3"); BaseProvider provider = new TestProvider(propertyIds); Set<String> supportedPropertyIds = provider.getPropertyIds(); assertTrue(supportedPropertyIds.containsAll(propertyIds)); }