/// <summary>
/// Side effect: state is managed in the _counters dictionary.
/// </summary>
/// <returns></returns>
private String GetNextCycleText(String groupName, CycleTag cycleTag)
{
int currentIndex;
// Create a like dictionary key entry to keep track of this declaration. THis takes the variable
// names (not the eval-ed variables) or literals and concatenates them together.
var key = "cycle_" + groupName + "_" + String.Join("|", cycleTag.CycleList.Select(x => x.Data.Expression.ToString()));
while (true)
{
currentIndex = _counters.GetOrAdd(key, 0);
var newindex = (currentIndex + 1) % cycleTag.Length;
// fails if updated concurrently by someone else.
if (_counters.TryUpdate(key, newindex, currentIndex))
{
break;
}
}
String result = "";
var currentElement = cycleTag.ElementAt(currentIndex);
LiquidExpressionEvaluator.Eval(currentElement, _templateContext)
.WhenSuccess(x => result = ValueCaster.RenderAsString(LiquidExpressionEvaluator.Eval(currentElement, _templateContext).SuccessResult.Value))
.WhenError(err => result = FormatErrors(new List <LiquidError> {
err
}));
return(result);
}
public void It_Should_Find_Elements_In_Its_Array()
{
// Arrange
var cycleTag = new CycleTag();
cycleTag.CycleList.Add(new TreeNode <LiquidExpression>(new LiquidExpression {
Expression = LiquidString.Create("A")
}));
cycleTag.CycleList.Add(new TreeNode <LiquidExpression>(new LiquidExpression {
Expression = LiquidString.Create("B")
}));
cycleTag.CycleList.Add(new TreeNode <LiquidExpression>(new LiquidExpression {
Expression = LiquidString.Create("C")
}));
// Assert
Assert.Equal("A", ((LiquidString)cycleTag.ElementAt(0).Data.Expression).StringVal);
Assert.Equal("B", ((LiquidString)cycleTag.ElementAt(1).Data.Expression).StringVal);
}
public void Visit(CycleTag cycleTag)
{
if (cycleTag.GroupNameExpressionTree == null)
{
AppendTextToCurrentAccumulator(GetNextCycleText(groupName: null, cycleTag: cycleTag));
}
else
{
// figure out the group name if any, otherwise use null.
LiquidExpressionEvaluator.Eval(cycleTag.GroupNameExpressionTree, _templateContext)
.WhenSuccess(
x =>
AppendTextToCurrentAccumulator(
GetNextCycleText(
groupName: x.HasValue ? ValueCaster.RenderAsString(x.Value) : null,
cycleTag: cycleTag)))
.WhenError(err => {
RegisterRenderingError(err);
//RenderError(err);
});
}
}
public void Visit(CycleTag cycleTag)
{
_result += cycleTag.ToString();
}
