From e1636d0f13e352d4af23cf1c6b8caa957096a181 Mon Sep 17 00:00:00 2001
From: mantikoros <sgrugett@gmail.com>
Date: Sat, 8 Oct 2022 12:16:38 -0500
Subject: [PATCH] update metrics: fix divide by zero, elasticity NaN bug

---
 common/calculate-metrics.ts     | 6 +++++-
 functions/src/update-metrics.ts | 2 +-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/common/calculate-metrics.ts b/common/calculate-metrics.ts
index 6cfb0421..9ad44522 100644
--- a/common/calculate-metrics.ts
+++ b/common/calculate-metrics.ts
@@ -97,7 +97,11 @@ export const computeBinaryCpmmElasticity = (
   )
   const resultNo = getCpmmProbability(poolN, pN)
 
-  return resultYes - resultNo
+  // handle AMM overflow
+  const safeYes = Number.isFinite(resultYes) ? resultYes : 1
+  const safeNo = Number.isFinite(resultNo) ? resultNo : 0
+
+  return safeYes - safeNo
 }
 
 export const computeDpmElasticity = (
diff --git a/functions/src/update-metrics.ts b/functions/src/update-metrics.ts
index 887dbbdc..4739dcc1 100644
--- a/functions/src/update-metrics.ts
+++ b/functions/src/update-metrics.ts
@@ -169,7 +169,7 @@ export async function updateMetricsCore() {
           return 0
         }
         const contractRatio =
-          contract.flaggedByUsernames.length / (contract.uniqueBettorCount ?? 1)
+          contract.flaggedByUsernames.length / (contract.uniqueBettorCount || 1)
 
         return contractRatio
       })