Fix stack overflow in FilterExpression.ValidForProperties

[engyebrahim]

Description

fixed the stack overflow in FilterExpression.ValidForProperties by replacing the recursion by iterative code (stacks and loops)

issue

• Fixes Test process crashes with stack overflow in FilterExpression.ValidForProperties #3905

[nohwnd]

@engyebrahim please add description to this PR, and prefix the linked issue by Fix or Fixes if you want to automatically close it. If the PR is still in progress please make it a draft.

[nohwnd]

Suggested change

	//Push root's right child and then root to stack then Set root as root's left child
	// Push root's right child and then root to stack then Set root as root's left child.

[Haplois]

I believe that entire comment is unnecessary, and more complicated than the code :)

[nohwnd]

The filtering logic is now a bit more unclear than it was before. And even before I did not really get fully how it works. Now that you probably have understanding of what is going on, could you please add comments with explanation of how it works to the code?

Could you also add a test with a very long filter that would otherwise stack overflow please?

[nohwnd]

Even though you could theoretically measure how many iterations it would take I think it is safe to assume that 100k entries test filter should be fast to process, and enough to test that we don't stackoverflow.

(measuring how many recursive calls are possible for a simple method:

        static int MeasureStack(int count)
        {
            try
            {
                RuntimeHelpers.EnsureSufficientExecutionStack();
                return MeasureStack(++count);
            } catch (InsufficientExecutionStackException)
            {
                return count;
            }
        }

Currently this is about 15k calls for .NET for this method.
)

[Evangelink]

Could you please add a test that was causing the stack overflow before so that we don't regress.

[nohwnd]

Suggested change

	for (int i = 0; i < 1e5; i++) // creating a 100k filter cases string
	// Create filter with 100k conditions.
	for (int i = 0; i < 100_000; i++)

[nohwnd]

just a nitpick.