fails:Hash#store associates the key with the value and return the value
fails:Hash#store duplicates string keys using dup semantics
fails:Hash#store stores unequal keys that hash to the same value
fails:Hash#store accepts keys with private #hash method
fails:Hash#store duplicates and freezes string keys
fails:Hash#store doesn't duplicate and freeze already frozen string keys
fails:Hash#store raises a RuntimeError if called on a frozen instance
fails:Hash#store does not raise an exception if changing the value of an existing key during iteration
