LGTM.com - false positive - [cs/dereferenced-value-may-be-null]

[DaveSkender]

Description of the false positive

Alert does not consider the order of events in the LINQ query; the value cannot be null.

URL to the alert on the project page on LGTM.com
https://lgtm.com/projects/g/DaveSkender/Stock.Indicators/snapshot/71ad67e9bc0c1c073362dc811972e76e48d98902/files/src/a-d/Dpo/Dpo.Utilities.cs?sort=name&dir=ASC&mode=heatmap#x73013381c2ffa1bb:1

return results
  .Where(x => x.Dpo != null)
  .Select(x => new Quote
  {
      Date = x.Date,
      Open = (decimal)x.Dpo,
      High = (decimal)x.Dpo,
      Low = (decimal)x.Dpo,
      Close = (decimal)x.Dpo,
      Volume = (decimal)x.Dpo
  })
  .ToList();

[tausbn]

Thank you for your report!

I agree that this looks like a false positive. It is likely that in this case the nullness analysis (which is mostly intra-procedural) doesn't allow the knowledge that x.Dpo is not null to escape outside the function that is passed to the Where method.

As we're currently focusing our efforts on improving our security analyses, and as this is not a security query, we will be adding this to our backlog, and address it in due course.

In the meantime, if the alert bothers you, you can always hide it on LGTM.com using the alert suppression available there (e.g. through the use of an alert suppression comment).

[intrigus-lgtm]

#5884
Might be related to this issue.