interface Result {
        /**
         * Returns the values snapshotted just now.
         */
        ImmutableSortedMap<String, ValueSnapshot> getValueSnapshots();

        /**
         * Returns all the value snapshots, including previously known ones.
         */
        ImmutableSortedMap<String, ValueSnapshot> getAllValueSnapshots();

        /**

            ImmutableSortedMap.of(),
            ImmutableSortedMap.of(),
            work::visitIdentityInputs
        );

        ImmutableSortedMap<String, ValueSnapshot> identityInputProperties = inputs.getValueSnapshots();
        ImmutableSortedMap<String, CurrentFileCollectionFingerprint> identityInputFileProperties = inputs.getFileFingerprints();
        Identity identity = work.identify(identityInputProperties, identityInputFileProperties);

            this.propertiesRequiringIsEmptyCheck = propertiesRequiringIsEmptyCheck;
        }

        @Override
        public ImmutableSortedMap<String, ValueSnapshot> getValueSnapshots() {
            return valueSnapshots;
        }

        @Override
        public ImmutableSortedMap<String, ValueSnapshot> getAllValueSnapshots() {

                    .map(InvalidUserDataException::new)
                    .collect(toImmutableList())
            );
        }

        for (Map.Entry<String, ValueSnapshot> entry : result.getValueSnapshots().entrySet()) {
            hasher.putString(entry.getKey());
            entry.getValue().appendToHasher(hasher);
        }