From 28ae4ef2d6248388aa86e58457f6a9a0fabb1823 Mon Sep 17 00:00:00 2001
From: Paul Wackerow <54227730+wackerow@users.noreply.github.com>
Date: Tue, 23 Sep 2025 10:24:13 -0700
Subject: [PATCH] fix: canonical test assignment for polyinstantiated tests

---
 app/[locale]/page.tsx             | 21 ++++++++++++++++-----
 src/components/AB/TestWrapper.tsx |  4 +++-
 2 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/app/[locale]/page.tsx b/app/[locale]/page.tsx
index 57aac0b0867..e48ae1b97cf 100644
--- a/app/[locale]/page.tsx
+++ b/app/[locale]/page.tsx
@@ -87,6 +87,7 @@ import IndexPageJsonLD from "./page-jsonld"
 import { getActivity, getUpcomingEvents } from "./utils"
 
 import { routing } from "@/i18n/routing"
+import { getABTestAssignment } from "@/lib/ab-testing/server"
 import { fetchCommunityEvents } from "@/lib/api/calendarEvents"
 import { fetchEthPrice } from "@/lib/api/fetchEthPrice"
 import { fetchGrowThePie } from "@/lib/api/fetchGrowThePie"
@@ -162,6 +163,9 @@ const Page = async ({ params }: { params: Promise<{ locale: Lang }> }) => {
   const tCommon = await getTranslations({ locale, namespace: "common" })
   const { direction: dir, isRtl } = getDirection(locale)
 
+  const DEVCONNECT_TEST_KEY = "2025-09-devconnect-banner"
+  const devconnectAssignment = await getABTestAssignment(DEVCONNECT_TEST_KEY)
+
   const [
     ethPrice,
     totalEthStaked,
@@ -432,8 +436,13 @@ const Page = async ({ params }: { params: Promise<{ locale: Lang }> }) => {
       <IndexPageJsonLD locale={locale} />
       <MainArticle className="flex w-full flex-col items-center" dir={dir}>
         <ABTestWrapper
-          testKey="2025-09-devconnect-banner"
-          variants={[<DevconnectBannerVariation1 key="variation-1" />, <></>]}
+          testKey={DEVCONNECT_TEST_KEY}
+          variants={[
+            <DevconnectBannerVariation1 key="a-variant-1" />,
+            <Fragment key="a-variant-2" />,
+          ]}
+          serverVariantIndex={devconnectAssignment?.variantIndex}
+          enableAllLocales
         />
         <HomeHero />
         <div className="w-full space-y-32 px-4 md:mx-6 lg:space-y-48">
@@ -478,11 +487,13 @@ const Page = async ({ params }: { params: Promise<{ locale: Lang }> }) => {
 
           <div className="!mt-0 w-full">
             <ABTestWrapper
-              testKey="2025-09-devconnect-banner"
+              testKey={DEVCONNECT_TEST_KEY}
               variants={[
-                <></>,
-                <DevconnectBannerVariation2 key="variation-2" />,
+                <Fragment key="b-variant-1" />,
+                <DevconnectBannerVariation2 key="b-variant-2" />,
               ]}
+              serverVariantIndex={devconnectAssignment?.variantIndex}
+              enableAllLocales
             />
           </div>
 
diff --git a/src/components/AB/TestWrapper.tsx b/src/components/AB/TestWrapper.tsx
index 34b1f6f4e61..f9d424eb4d5 100644
--- a/src/components/AB/TestWrapper.tsx
+++ b/src/components/AB/TestWrapper.tsx
@@ -17,6 +17,7 @@ type ABTestWrapperProps = {
   variants: ABTestVariants
   fallback?: ReactNode
   enableAllLocales?: boolean
+  serverVariantIndex?: number // Only required if testKey instantiates more than one ABTestWrapper
 }
 
 const ABTestWrapper = async ({
@@ -24,6 +25,7 @@ const ABTestWrapper = async ({
   variants,
   fallback,
   enableAllLocales,
+  serverVariantIndex,
 }: ABTestWrapperProps) => {
   const locale = await getLocale()
   if (locale !== DEFAULT_LOCALE && !enableAllLocales)
@@ -36,7 +38,7 @@ const ABTestWrapper = async ({
     if (!assignment) throw new Error("No AB test assignment found")
 
     // Use assignment's variant index directly
-    const variantIndex = assignment.variantIndex
+    const variantIndex = serverVariantIndex ?? assignment.variantIndex
 
     // Extract labels from React element keys or fall back to defaults
     const availableVariants = variants.map((variant, i) => {