public void EvaluateConcatenateExpressionUsingNulls()
{
IExpression expression = new ConcatenateExpression(new ConstantExpression(null), new ConstantExpression(null));
Assert.AreEqual(string.Empty, expression.Evaluate(null));
expression = new ConcatenateExpression(new ConstantExpression("foo"), new ConstantExpression(null));
Assert.AreEqual("foo", expression.Evaluate(null));
expression = new ConcatenateExpression(new ConstantExpression(null), new ConstantExpression("bar"));
Assert.AreEqual("bar", expression.Evaluate(null));
}
public void EvaluateConcatenateExpressionUsingIntegers()
{
IExpression expression = new ConcatenateExpression(new ConstantExpression(12), new ConstantExpression(34));
Assert.AreEqual("1234", expression.Evaluate(null));
}