shrink method

@override Iterable<Shrinkable<R>> shrink()

Generates an Iterable of Shrinkables that fulfill the following criteria:

• They are similar to this: They only differ in little ways.
• They are simpler than this: The transitive hull is finite acyclic. If you would call shrink on all returned values and on the values returned by them etc., this process should terminate sometime.

Implementation

@override
Iterable<Shrinkable<R>> shrink() {
  return originalValue.shrink().map((value) {
    return MappedShrinkableValue(value, mapper);
  });
}