public void ForBreak()
{
var counter = new Counter();
var c = Expression.Parameter(typeof(Counter), "c");
var l = Expression.Parameter(typeof(int), "l");
var i = Expression.Variable(typeof(int), "i");
var for_break = Expression.Label("for_break");
var hitcounter = Expression.Lambda <Action <Counter, int> > (
CustomExpression.For(
i,
Expression.Constant(0),
Expression.LessThan(i, l),
Expression.PreIncrementAssign(i),
Expression.Block(
Expression.Condition(
Expression.LessThan(i, Expression.Constant(10)),
Expression.Call(c, typeof(Counter).GetMethod("Hit", Type.EmptyTypes)),
Expression.Goto(for_break))),
for_break),
c, l).Compile();
hitcounter(counter, 100);
Assert.AreEqual(10, counter.Count);
}
public void ForVisit()
{
var i = Expression.Variable(typeof(int), "i");
var for_break = Expression.Label("for_break");
var for_continue = Expression.Label("for_continue");
var forExpression = CustomExpression.For(
i,
Expression.Constant(0),
Expression.LessThan(i, Expression.Constant(1)),
Expression.PreIncrementAssign(i),
Expression.Constant(null),
for_break,
for_continue);
var visitedForExpression = (ForExpression)(new ReplaceNullByDefaultVisitor().Visit(forExpression));
Assert.AreNotEqual(forExpression, visitedForExpression);
Assert.AreEqual(forExpression.Variable, visitedForExpression.Variable);
Assert.AreEqual(forExpression.Initializer, visitedForExpression.Initializer);
Assert.AreEqual(forExpression.Test, visitedForExpression.Test);
Assert.AreEqual(forExpression.Step, visitedForExpression.Step);
Assert.AreEqual(ExpressionType.Default, visitedForExpression.Body.NodeType);
Assert.AreEqual(forExpression.BreakTarget, visitedForExpression.BreakTarget);
Assert.AreEqual(forExpression.ContinueTarget, visitedForExpression.ContinueTarget);
}
public void For()
{
var l = Expression.Parameter(typeof(int), "l");
var i = Expression.Variable(typeof(int), "i");
var lambda = Expression.Lambda <Action <int> > (
CustomExpression.For(
i,
Expression.Constant(0),
Expression.LessThan(i, l),
Expression.PreIncrementAssign(i),
Expression.Call(typeof(Console).GetMethod("WriteLine", new [] { typeof(int) }), i)),
l);
AssertExpression(@"
void (int l)
{
for (int i = 0; i < l; ++i)
{
Console.WriteLine(i);
}
}
", lambda);
}
public ForExpression Update(ParameterExpression variable, Expression initializer, Expression test, Expression step, Expression body, LabelTarget breakTarget, LabelTarget continueTarget)
{
if (this.variable == variable && this.initializer == initializer && this.test == test && this.step == step && this.body == body && this.break_target == breakTarget && this.continue_target == continueTarget)
{
return(this);
}
return(CustomExpression.For(variable, initializer, test, step, body, breakTarget, continueTarget));
}
public void Never()
{
var counter = new Counter();
var c = Expression.Parameter(typeof(Counter), "c");
var l = Expression.Parameter(typeof(int), "l");
var i = Expression.Variable(typeof(int), "i");
var hitcounter = Expression.Lambda <Action <Counter, int> > (
CustomExpression.For(
i,
Expression.Constant(0),
Expression.LessThan(i, l),
Expression.PreIncrementAssign(i),
Expression.Call(c, typeof(Counter).GetMethod("Hit", Type.EmptyTypes))),
c, l).Compile();
hitcounter(counter, 0);
Assert.AreEqual(0, counter.Count);
}
