public void CollapsesPreviousWhiteSpace()
		{
			var factory = new Factory();
			
			// "Hello {{~test}}"
			var document = factory.Document(
				factory.Text("Hello"),
				factory.WhiteSpace(1),
				factory.Expression(
					factory.MetaCode("{{", T.OpenTag),
					factory.MetaCode("~", T.Tilde),
					factory.Span(SpanKind.Expression, factory.Symbol("this", T.Identifier)),
					factory.MetaCode("}}", T.CloseTag)));

			factory = new Factory();

			// "Hello{{~test}}"
			var expected = factory.Document(
				factory.Text("Hello"),
				factory.WhiteSpace(1, collapsed: true),
				factory.Expression(
					factory.MetaCode("{{", T.OpenTag),
					factory.MetaCode("~", T.Tilde),
					factory.Span(SpanKind.Expression, factory.Symbol("this", T.Identifier)),
					factory.MetaCode("}}", T.CloseTag)));

			var visitor = new WhiteSpaceCollapsingParserVisitor();
			visitor.VisitBlock(document);

			var builder = new StringBuilder();
			var comparer = new EquivalanceComparer(builder, 0);

			Assert.True(comparer.Equals(expected, document), builder.ToString());
		}