Unhandled NullReferenceException being thrown

[musabhusaini]

Issue:

A NullReferenceException is being thrown when trying to call Next that has no result.

Scenario:

Assuming document is a CQ object, I am making a call similar to:

var elem = document["#content.results > table > tbody > tr > td:nth-child(1) > a:nth-child(1)"].First();
// Do something with elem
var link = elem.Parent().Next("td").Children("a").First();
// NullReferenceException thrown.

In fact, there is no Next("td"), but as I understand it, the call should fail silently and return an empty CQ object. Instead, a NullReferenceException is thrown. Let me know if I can provide more useful diagnostic information.

Exception Details:

System.NullReferenceException was unhandled
  HResult=-2147467261
  Message=Object reference not set to an instance of an object.
  Source=CsQuery
  StackTrace:
       at CsQuery.Engine.SelectorEngine.Select(IEnumerable`1 context)
       at CsQuery.Engine.Selector.Select(IDomDocument document, IEnumerable`1 context)
       at CsQuery.Engine.Selector.<Filter>d__6.MoveNext()
       at CsQuery.CQ.AddSelection(IEnumerable`1 elements)
       at CsQuery.CQ.ConfigureNewInstance(CQ dom, IEnumerable`1 elements, CQ context)
       at CsQuery.CQ.NewInstance(IEnumerable`1 elements, CQ context)
       at CsQuery.CQ.FilterIfSelector(String selector, IEnumerable`1 list, SelectionSetOrder order)
       at CsQuery.CQ.nextPrevImpl(String selector, Boolean next)
       at CsQuery.CQ.Next(String selector)
       ...

[jamietre]

I just tried this with some random HTML that matches nothing (so there are no results at any step) and it works fine. Can you confirm you're using 1.3, and if so show me some html that fails with this selector?

[musabhusaini]

Yes, I am using 1.3. I loaded up this page using CQ.CreateDocument(string html) and the following code failed for me:

document.Cq()["#content.results > table > tbody > tr > td:nth-child(1) > a:nth-child(1)"].Eq(19).Parent().Next("td").Children("a").First()

[jamietre]

OK tracked it down, fix shortly.

[musabhusaini]

Great!

[jamietre]

Fix on github now. There will be an update to nuget whenever I finish dealing with the encoding issue (#52) but the dist code here should solve this problem.