From ceb06bed61010b9f71b1fc0bf76ba239f5f0b129 Mon Sep 17 00:00:00 2001
From: Lam Wei Li <peteriman@mail.com>
Date: Fri, 18 Feb 2022 16:27:22 +0800
Subject: [PATCH] Fixed serialise() for NaN, Infinity, -Infinity and undefined

---
 lib/LoggingEvent.js | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/lib/LoggingEvent.js b/lib/LoggingEvent.js
index 60ce832..5732a27 100644
--- a/lib/LoggingEvent.js
+++ b/lib/LoggingEvent.js
@@ -35,9 +35,20 @@ class LoggingEvent {
     const logData = this.data.map((e) => {
       // JSON.stringify(new Error('test')) returns {}, which is not really useful for us.
       // The following allows us to serialize errors correctly.
+      // duck-typing for Error object
       if (e && e.message && e.stack) {
         e = Object.assign({ message: e.message, stack: e.stack }, e);
       }
+      // JSON.stringify({a: parseInt('abc'), b: 1/0, c: -1/0}) returns {a: null, b: null, c: null}.
+      // The following allows us to serialize to NaN, Infinity and -Infinity correctly.
+      else if (typeof e === 'number' && (isNaN(e) || !isFinite(e))) {
+        e = e.toString();
+      }
+      // JSON.stringify([undefined]) returns [null].
+      // The following allows us to serialize to undefined correctly.
+      else if (typeof e === 'undefined') {
+        e = typeof e;
+      }
       return e;
     });
     this.data = logData;