Intent of editSurvivalTracker.test|title=agentHost editSurvivalTracker computeFractionPresentIn chunk fully present in current → 1|occurrence=1, editSurvivalTracker.test|title=agentHost editSurvivalTracker computeFractionPresentIn partial overlap → fraction between 0 and 1|occurrence=1, +1

All 3 exact tests in this concept. Every test is marked by where it enters the hierarchy.