public void GroupToDictionary_WithNonEmptyEnumerableAndIdentifyFunction_ExpectsDictionaryOfSingles()
        {
            var dictionary = ENMRBL_NON_EMPTY.GroupToDictionary(DefaultDelegates.IdentityFunction <MultiItems>());

            Equal(ENMRBL_NON_EMPTY.ToList(), dictionary.Keys);
            Utilities.AssertManySequencesEqual(
                ENMRBL_NON_EMPTY.Select(item => new[] { item }),
                dictionary.Values);
        }
 public void GroupToDictionary_WithNullValueSelector_Throws()
 => Throws <ArgumentNullException>(
     () => ENMRBL_NON_EMPTY.GroupToDictionary <MultiItems, MultiItems, MultiItems>(
         DefaultDelegates.IdentityFunction <MultiItems>(), null));
 public void GroupToDictionary_WithNullKeySelector_Throws()
 => Throws <ArgumentNullException>(
     () => ENMRBL_NON_EMPTY.GroupToDictionary <MultiItems, MultiItems>(null));