};
    for (char surrogate : surrogates) {
      builder.add(newString(surrogate));
      builder.add(newString(surrogate, 'n'));
      builder.add(newString('n', surrogate));
      builder.add(newString(surrogate, surrogate));
    }
    builder.add(newString(MIN_LOW_SURROGATE, MAX_HIGH_SURROGATE));
    ILL_FORMED_STRINGS = builder.build();
  }

This is preferred for entirely new things:

```groovy
public interface NewThing {
    Property<String> getSomeProperty()
}

// in plugin
newThing = objects.newInstance(NewThing.class)
newThing.convention("some-value")
```

This is acceptable for existing things:

```groovy
public interface ExistingThing {