Test Tree View quadratically slower for huge number of tests

I've known since a long time that the test runner test list view gets horrendously slow when you want to run lots of tests in the interactive editor. We got like 80k individual tests and trying to run them will take ages inside the TestTreeViewBuilder because it's O(n²) looking for previous test results:

Code (CSharp):

1. m_OldTestResultList.FirstOrDefault(a => a.uniqueId == testElementId);

inside of

TestTreeViewBuilder.ParseTestTree()

.

I think a simple O(n log n) lookup cache for the old test results would work wonders here.

com.unity.test-framework@1.1.19

 

In a quick test I've replaced m_OldTestResultList with a Dictionary<> instead of a List<> and it is magnitudes faster. Still not "interactive" I'd say but at least I don't have to wait half an hour for the editor to become responsive again.

 

We reported this with a minimal repro and patch a month ago: Zendesk id #939374, bug report 1289626. Please check those out