public void ConstructorShouldCopySequence()
        {
            // arrange
            var expected = new[] { "1", "2", "3" };

            // act
            var target = new ObservableQueue<string>( expected );

            // assert
            Assert.Equal( 3, target.Count );
            Assert.True( expected.All( i => target.Contains( i ) ) );
        }
        public void ShouldContainItem( string value, bool expected )
        {
            // arrange
            var target = new ObservableQueue<string>();
            
            target.Enqueue( "One" );
            target.Enqueue( "Two" );
            target.Enqueue( "Three" );
            
            // act
            var actual = target.Contains( value );

            // assert
            Assert.Equal( expected, actual );
        }