public void ShouldTranslateALoopWithABreakStatement()
{
var intVariable = Expression.Variable(typeof(int), "i");
var intGreaterThanTwo = Expression.GreaterThan(intVariable, Expression.Constant(2));
var breakLoop = Expression.Break(Expression.Label());
var ifGreaterThanTwoBreak = Expression.IfThen(intGreaterThanTwo, breakLoop);
var writeLine = CreateLambda(() => Console.WriteLine());
var incrementVariable = Expression.Increment(intVariable);
var loopBody = Expression.Block(ifGreaterThanTwoBreak, writeLine.Body, incrementVariable);
var loop = Expression.Loop(loopBody, breakLoop.Target);
var translated = ToReadableString(loop);
const string EXPECTED = @"
while (true)
{
if (i > 2)
{
break;
}
Console.WriteLine();
++i;
}";
translated.ShouldBe(EXPECTED.TrimStart());
}
public void ShouldTranslateAMultipleLineIfStatementTest()
{
var intVariable = Expression.Variable(typeof(int), "i");
var one = Expression.Constant(1);
var intVariableLessThanOne = Expression.LessThan(intVariable, one);
var returnLabel = Expression.Label(typeof(bool), "Return");
var returnTrue = Expression.Return(returnLabel, Expression.Constant(true));
var ifLessThanOneReturnTrue = Expression.IfThen(intVariableLessThanOne, returnTrue);
var five = Expression.Constant(5);
var intVariableMoreThanFive = Expression.GreaterThan(intVariable, five);
var returnMoreThanFive = Expression.Label(returnLabel, intVariableMoreThanFive);
var testBlock = Expression.Block(ifLessThanOneReturnTrue, returnMoreThanFive);
var writeHello = CreateLambda(() => Console.WriteLine("Hello"));
var writeVariable = Expression.Variable(writeHello.Type, "write");
var assignWrite = Expression.Assign(writeVariable, writeHello);
var ifTestPassesThenWrite = Expression.IfThen(testBlock, assignWrite);
var translated = ToReadableString(ifTestPassesThenWrite);
const string EXPECTED = @"
if ({
if (i < 1)
{
return true;
}
return i > 5;
})
{
write = () => Console.WriteLine(""Hello"");
}";
translated.ShouldBe(EXPECTED.TrimStart());
}
public void ShouldWrapAnAssignmentTernaryTestInParentheses()
{
var intVariable1 = Expression.Variable(typeof(int), "i");
var intVariable2 = Expression.Variable(typeof(int), "j");
var intVariable2GreaterThanOne = Expression.GreaterThan(intVariable2, Expression.Constant(1));
var threeOrDefault = Expression.Condition(
intVariable2GreaterThanOne,
Expression.Constant(3),
Expression.Default(typeof(int)));
var assignment = Expression.Assign(intVariable1, threeOrDefault);
var translated = ToReadableString(assignment);
translated.ShouldBe("i = (j > 1) ? 3 : default(int)");
}
public void ShouldTranslateAMultipleClauseIfStatement()
{
var intVariable = Expression.Variable(typeof(int), "i");
var one = Expression.Constant(1);
var intVariableLessThanOne = Expression.LessThan(intVariable, one);
var intVariableMoreThanOne = Expression.GreaterThan(intVariable, one);
var intVariableInRange = Expression.AndAlso(intVariableLessThanOne, intVariableMoreThanOne);
var writeHello = CreateLambda(() => Console.WriteLine("Hello"));
var ifLessThanOneThenWrite = Expression.IfThen(intVariableInRange, writeHello.Body);
var translated = ToReadableString(ifLessThanOneThenWrite);
const string EXPECTED = @"
if ((i < 1) && (i > 1))
{
Console.WriteLine(""Hello"");
}";
translated.ShouldBe(EXPECTED.TrimStart());
}
public void ShouldBreakLongMultipleConditionsOntoMultipleLines()
{
var intVariable1 = Expression.Variable(typeof(int), "thisVariableHasALongName");
var intVariable2 = Expression.Variable(typeof(int), "thisOtherVariableHasALongNameToo");
var int1IsGreaterThanInt2 = Expression.GreaterThan(intVariable1, intVariable2);
var int1IsNotEqualToInt2 = Expression.NotEqual(intVariable1, intVariable2);
var intIsInRange = Expression.AndAlso(int1IsGreaterThanInt2, int1IsNotEqualToInt2);
var writeYo = CreateLambda(() => Console.WriteLine("Yo!"));
var ifInRangeWriteYo = Expression.IfThen(intIsInRange, writeYo.Body);
var translated = ToReadableString(ifInRangeWriteYo);
const string EXPECTED = @"
if ((thisVariableHasALongName > thisOtherVariableHasALongNameToo) &&
(thisVariableHasALongName != thisOtherVariableHasALongNameToo))
{
Console.WriteLine(""Yo!"");
}";
translated.ShouldBe(EXPECTED.TrimStart());
}
