public void HasVariablesWithVariable()
{
Variable variable = new Variable("X");
MatchExpression expr = new MatchExpression(new VariableExpression(variable), new ConstantExpression(123));
Assert.IsTrue(expr.HasVariable());
}
public static List MakeList(IList<object> elements, Variable tail)
{
if (elements.Count == 1)
return new List(elements[0], tail);
return new List(elements[0], MakeList(elements.Skip(1).ToList(), tail));
}
public void CreateSimpleVariableExpression()
{
Variable variable = new Variable("X");
VariableExpression expression = new VariableExpression(variable);
Assert.AreEqual(variable, expression.Variable);
}
public void EvaluateUndefinedVariableExpression()
{
Variable variable = new Variable("X");
Context context = new Context();
VariableExpression expression = new VariableExpression(variable);
Assert.AreEqual(variable, expression.Evaluate(context, true));
}
public void EvaluateVariableExpression()
{
Variable variable = new Variable("X");
Context context = new Context();
context.SetValue("X", 1);
VariableExpression expression = new VariableExpression(variable);
Assert.AreEqual(1, expression.Evaluate(context));
}
public void RaiseIfEvaluateUndefinedVariableExpression()
{
Variable variable = new Variable("X");
Context context = new Context();
VariableExpression expression = new VariableExpression(variable);
try
{
expression.Evaluate(context, false);
Assert.Fail();
}
catch (Exception ex)
{
Assert.AreEqual("variable 'X' is unbound", ex.Message);
}
}
public void Equals()
{
Variable variable1 = new Variable("X");
Variable variable2 = new Variable("Y");
Variable variable3 = new Variable("X");
Assert.AreEqual(variable1, variable3);
Assert.AreEqual(variable3, variable1);
Assert.AreEqual(variable1.GetHashCode(), variable3.GetHashCode());
Assert.IsFalse(variable1.Equals(null));
Assert.IsFalse(variable1.Equals(123));
Assert.IsFalse(variable1.Equals("foo"));
Assert.AreNotEqual(variable1, variable2);
Assert.AreNotEqual(variable2, variable1);
}
public void MatchOneAtomAndTwoVariablesInTupleWithConcreteTuple()
{
Context context = new Context();
Atom p = new Atom("point");
Variable x = new Variable("X");
Variable y = new Variable("Y");
MatchExpression expr = new MatchExpression(new TupleExpression(new IExpression[] { new AtomExpression(p), new VariableExpression(x), new VariableExpression(y) }), new TupleExpression(new IExpression[] { new AtomExpression(new Atom("point")), new ConstantExpression(1), new ConstantExpression(2) }));
expr.Evaluate(context);
var result1 = context.GetValue("X");
var result2 = context.GetValue("Y");
Assert.IsNotNull(result1);
Assert.AreEqual(1, result1);
Assert.IsNotNull(result2);
Assert.AreEqual(2, result2);
}
public void MatchTwoVariablesWithList()
{
Context context = new Context();
Variable headvar = new Variable("H");
Variable tailvar = new Variable("T");
var list = new List(headvar, tailvar);
var list2 = new List(1, new List(2, new List(3, null)));
MatchExpression expr = new MatchExpression(new ConstantExpression(list), new ConstantExpression(list2));
expr.Evaluate(context);
var result1 = context.GetValue("H");
var result2 = context.GetValue("T");
Assert.IsNotNull(result1);
Assert.AreEqual(1, result1);
Assert.IsNotNull(result2);
Assert.IsInstanceOfType(result2, typeof(List));
Assert.AreEqual("[2,3]", result2.ToString());
}
public void RaiseIfMatchVariableInTupleWithTwoDifferentValues()
{
Context context = new Context();
Variable x = new Variable("X");
MatchExpression expr = new MatchExpression(new TupleExpression(new IExpression[] { new VariableExpression(x), new VariableExpression(x) }), new TupleExpression(new IExpression[] { new ConstantExpression(1), new ConstantExpression(2) }));
try
{
expr.Evaluate(context);
Assert.Fail();
}
catch (Exception ex)
{
Assert.IsInstanceOfType(ex, typeof(InvalidOperationException));
Assert.AreEqual("no match of right hand side value {1,2}", ex.Message);
}
}
public void RaiseIfMatchBoundVariableWithInteger()
{
Context context = new Context();
Variable variable = new Variable("X");
context.SetValue("X", 1);
MatchExpression expr = new MatchExpression(new VariableExpression(variable), new ConstantExpression(123));
try
{
expr.Evaluate(context);
Assert.Fail();
}
catch (Exception ex)
{
Assert.IsInstanceOfType(ex, typeof(InvalidOperationException));
Assert.AreEqual("no match of right hand side value 123", ex.Message);
}
}
public void MatchVariableWithInteger()
{
Context context = new Context();
Variable variable = new Variable("X");
MatchExpression expr = new MatchExpression(new VariableExpression(variable), new ConstantExpression(123));
Assert.AreEqual(123, expr.Evaluate(context));
Assert.AreEqual(123, context.GetValue("X"));
}
public void VariableToString()
{
Variable variable = new Variable("X");
Assert.AreEqual("X", variable.ToString());
}
public void FirstVariable()
{
Variable variable = new Variable("X");
Assert.AreEqual(variable, variable.FirstVariable());
}
public void CreateSimpleVariable()
{
Variable variable = new Variable("X");
Assert.AreEqual("X", variable.Name);
}
public VariableExpression(Variable variable)
{
this.variable = variable;
}
