From a2f2557679852330058600245f05e3399e42891e Mon Sep 17 00:00:00 2001
From: Paul D'Ambra <paul@posthog.com>
Date: Mon, 23 Oct 2023 12:10:54 +0100
Subject: [PATCH] is null too

---
 src/autocapture-utils.ts                   |  4 ++--
 src/autocapture.ts                         |  8 ++++----
 src/extensions/exceptions/type-checking.ts |  4 ++--
 src/utils.ts                               | 12 ++++++++----
 4 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/src/autocapture-utils.ts b/src/autocapture-utils.ts
index abcb7c227..c0d3dc97f 100644
--- a/src/autocapture-utils.ts
+++ b/src/autocapture-utils.ts
@@ -4,7 +4,7 @@
  * @returns {string} the element's class
  */
 import { AutocaptureConfig } from 'types'
-import { _each, _includes, _isString, _isUndefined, _trim, logger } from './utils'
+import { _each, _includes, _isNull, _isString, _isUndefined, _trim, logger } from './utils'
 
 export function getClassName(el: Element): string {
     switch (typeof el.className) {
@@ -264,7 +264,7 @@ export function isSensitiveElement(el: Element): boolean {
  * @returns {boolean} whether the element should be captured
  */
 export function shouldCaptureValue(value: string): boolean {
-    if (value === null || _isUndefined(value)) {
+    if (_isNull(value) || _isUndefined(value)) {
         return false
     }
 
diff --git a/src/autocapture.ts b/src/autocapture.ts
index 935762c8d..a96bff61a 100644
--- a/src/autocapture.ts
+++ b/src/autocapture.ts
@@ -5,6 +5,7 @@ import {
     _includes,
     _isBoolean,
     _isFunction,
+    _isNull,
     _isUndefined,
     _register_event,
     _safewrap_instance_methods,
@@ -43,10 +44,9 @@ const autocapture = {
     _isAutocaptureEnabled: false as boolean,
 
     _setIsAutocaptureEnabled: function (instance: PostHog): void {
-        const disabled_server_side =
-            this._isDisabledServerSide === null
-                ? !!instance.persistence?.props[AUTOCAPTURE_DISABLED_SERVER_SIDE]
-                : this._isDisabledServerSide
+        const disabled_server_side = _isNull(this._isDisabledServerSide)
+            ? !!instance.persistence?.props[AUTOCAPTURE_DISABLED_SERVER_SIDE]
+            : this._isDisabledServerSide
         const enabled_client_side = !!instance.config.autocapture
         this._isAutocaptureEnabled = enabled_client_side && !disabled_server_side
     },
diff --git a/src/extensions/exceptions/type-checking.ts b/src/extensions/exceptions/type-checking.ts
index 2b01b83e6..e8f6f5abe 100644
--- a/src/extensions/exceptions/type-checking.ts
+++ b/src/extensions/exceptions/type-checking.ts
@@ -1,4 +1,4 @@
-import { _isFunction, _isObject, _isUndefined } from '../../utils'
+import { _isFunction, _isNull, _isObject, _isUndefined } from '../../utils'
 
 export function isEvent(candidate: unknown): candidate is Event {
     return !_isUndefined(Event) && isInstanceOf(candidate, Event)
@@ -19,7 +19,7 @@ export function isInstanceOf(candidate: unknown, base: any): boolean {
 export function isPrimitive(
     candidate: unknown
 ): candidate is number | string | boolean | bigint | symbol | null | undefined {
-    return candidate === null || (!_isObject(candidate) && !_isFunction(candidate))
+    return _isNull(candidate) || (!_isObject(candidate) && !_isFunction(candidate))
 }
 
 export function isError(candidate: unknown): candidate is Error {
diff --git a/src/utils.ts b/src/utils.ts
index 0cfef8e53..7d765f124 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -97,10 +97,10 @@ export function _eachArray<E = any>(
  * @param {Object=} thisArg
  */
 export function _each(obj: any, iterator: (value: any, key: any) => void | Breaker, thisArg?: any): void {
-    if (obj === null || obj === undefined) {
+    if (_isNull(obj) || _isUndefined(obj)) {
         return
     }
-    if (Array.isArray(obj)) {
+    if (_isArray(obj)) {
         return _eachArray(obj, iterator, thisArg)
     }
     for (const key in obj) {
@@ -145,7 +145,7 @@ export const _include = function (
     target: any
 ): boolean | Breaker {
     let found = false
-    if (obj === null) {
+    if (_isNull(obj)) {
         return found
     }
     if (nativeIndexOf && obj.indexOf === nativeIndexOf) {
@@ -200,6 +200,10 @@ export const _isUndefined = function (obj: any): obj is undefined {
     return obj === void 0
 }
 
+export const _isNull = function (obj: any): obj is null {
+    return obj === null
+}
+
 export const _isString = function (obj: any): obj is string {
     return toString.call(obj) == '[object String]'
 }
@@ -545,7 +549,7 @@ export const _getQueryParam = function (url: string, param: string): string {
     const regexS = '[\\?&]' + cleanParam + '=([^&#]*)'
     const regex = new RegExp(regexS)
     const results = regex.exec(url)
-    if (results === null || (results && !_isString(results[1]) && (results[1] as any).length)) {
+    if (_isNull(results) || (results && !_isString(results[1]) && (results[1] as any).length)) {
         return ''
     } else {
         let result = results[1]