From f9a374c0aa21636e4f3ebde0458de64fe4985f10 Mon Sep 17 00:00:00 2001
From: Ben White <ben@posthog.com>
Date: Wed, 24 Apr 2024 17:25:28 +0200
Subject: [PATCH] Add tests

---
 src/__tests__/heatmaps.test.ts | 36 ++++++++++++++++++++++++++++++++++
 src/heatmaps.ts                | 10 +++++-----
 2 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/src/__tests__/heatmaps.test.ts b/src/__tests__/heatmaps.test.ts
index 9432dbde1..4d86051dd 100644
--- a/src/__tests__/heatmaps.test.ts
+++ b/src/__tests__/heatmaps.test.ts
@@ -1,6 +1,8 @@
 import { createPosthogInstance } from './helpers/posthog-instance'
 import { uuidv7 } from '../uuidv7'
 import { PostHog } from '../posthog-core'
+import { HEATMAPS_ENABLED_SERVER_SIDE } from '../constants'
+import { DecideResponse } from '../types'
 jest.mock('../utils/logger')
 
 describe('heatmaps', () => {
@@ -105,4 +107,38 @@ describe('heatmaps', () => {
         )
         expect(posthog.heatmaps?.['buffer']).not.toEqual(undefined)
     })
+
+    describe('afterDecideResponse()', () => {
+        it('should not be enabled before the decide response', () => {
+            expect(posthog.heatmaps!.isEnabled).toBe(false)
+        })
+
+        it('should be enabled if client config option is enabled', () => {
+            posthog.config.__preview_heatmaps = true
+            expect(posthog.heatmaps!.isEnabled).toBe(true)
+        })
+
+        it.each([
+            // Client not defined
+            [undefined, false, false],
+            [undefined, true, true],
+            [undefined, false, false],
+            // Client false
+            [false, false, false],
+            [false, true, false],
+
+            // Client true
+            [true, false, true],
+            [true, true, true],
+        ])(
+            'when client side config is %p and remote opt in is %p - heatmaps enabled should be %p',
+            (clientSideOptIn, serverSideOptIn, expected) => {
+                posthog.config.__preview_heatmaps = clientSideOptIn
+                posthog.heatmaps!.afterDecideResponse({
+                    heatmaps: serverSideOptIn,
+                } as DecideResponse)
+                expect(posthog.heatmaps!.isEnabled).toBe(expected)
+            }
+        )
+    })
 })
diff --git a/src/heatmaps.ts b/src/heatmaps.ts
index 620dd9f54..987ce5fe1 100644
--- a/src/heatmaps.ts
+++ b/src/heatmaps.ts
@@ -6,6 +6,7 @@ import { PostHog } from './posthog-core'
 import { document, window } from './utils/globals'
 import { getParentElement, isTag } from './autocapture-utils'
 import { HEATMAPS_ENABLED_SERVER_SIDE } from './constants'
+import { isUndefined } from './utils/type-utils'
 
 type HeatmapEventBuffer =
     | {
@@ -50,6 +51,7 @@ export class Heatmaps {
 
     constructor(instance: PostHog) {
         this.instance = instance
+        this._enabledServerSide = !!this.instance.persistence?.props[HEATMAPS_ENABLED_SERVER_SIDE]
     }
 
     public startIfEnabled(): void {
@@ -59,11 +61,9 @@ export class Heatmaps {
     }
 
     public get isEnabled(): boolean {
-        return (
-            !!this.instance.config.__preview_heatmaps ||
-            !!this._enabledServerSide ||
-            !!this.instance.persistence?.props[HEATMAPS_ENABLED_SERVER_SIDE]
-        )
+        return !isUndefined(this.instance.config.__preview_heatmaps)
+            ? this.instance.config.__preview_heatmaps
+            : this._enabledServerSide
     }
 
     public afterDecideResponse(response: DecideResponse) {