From 1409a4a492fde146836dce09d70634e75ea05ed0 Mon Sep 17 00:00:00 2001
From: Demetrio Girardi <dgirardi@prebid.org>
Date: Fri, 16 Aug 2024 06:44:34 -0700
Subject: [PATCH] Core: make sure adUnitCodes are unique in auction events
 (#12127)

---
 src/prebid.js                   |  4 ++++
 test/spec/unit/pbjs_api_spec.js | 19 ++++++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/src/prebid.js b/src/prebid.js
index c92ab8f5a89..0eaccf5a8a6 100644
--- a/src/prebid.js
+++ b/src/prebid.js
@@ -503,6 +503,9 @@ pbjsInstance.requestBids = (function() {
     events.emit(REQUEST_BIDS);
     const cbTimeout = timeout || config.getConfig('bidderTimeout');
     logInfo('Invoking $$PREBID_GLOBAL$$.requestBids', arguments);
+    if (adUnitCodes != null && !Array.isArray(adUnitCodes)) {
+      adUnitCodes = [adUnitCodes];
+    }
     if (adUnitCodes && adUnitCodes.length) {
       // if specific adUnitCodes supplied filter adUnits for those codes
       adUnits = adUnits.filter(unit => includes(adUnitCodes, unit.code));
@@ -510,6 +513,7 @@ pbjsInstance.requestBids = (function() {
       // otherwise derive adUnitCodes from adUnits
       adUnitCodes = adUnits && adUnits.map(unit => unit.code);
     }
+    adUnitCodes = adUnitCodes.filter(uniques);
     const ortb2Fragments = {
       global: mergeDeep({}, config.getAnyConfig('ortb2') || {}, ortb2 || {}),
       bidder: Object.fromEntries(Object.entries(config.getBidderConfig()).map(([bidder, cfg]) => [bidder, cfg.ortb2]).filter(([_, ortb2]) => ortb2 != null))
diff --git a/test/spec/unit/pbjs_api_spec.js b/test/spec/unit/pbjs_api_spec.js
index de267b793b2..558fb17dc42 100644
--- a/test/spec/unit/pbjs_api_spec.js
+++ b/test/spec/unit/pbjs_api_spec.js
@@ -1843,7 +1843,24 @@ describe('Unit: Prebid Module', function () {
           adUnitCodes: 'two'
         });
         sinon.assert.calledWith(startAuctionStub, sinon.match({
-          adUnits: [{code: 'two'}]
+          adUnits: [{code: 'two'}],
+          adUnitCodes: ['two']
+        }));
+      });
+
+      it('does not repeat ad unit codes on twin ad units', () => {
+        $$PREBID_GLOBAL$$.requestBids({
+          adUnits: [{code: 'au1'}, {code: 'au2'}, {code: 'au1'}, {code: 'au2'}],
+        });
+        sinon.assert.calledWith(startAuctionStub, sinon.match({
+          adUnitCodes: ['au1', 'au2']
+        }));
+      });
+
+      it('filters out repeated ad unit codes from input', () => {
+        $$PREBID_GLOBAL$$.requestBids({adUnitCodes: ['au1', 'au1', 'au2']});
+        sinon.assert.calledWith(startAuctionStub, sinon.match({
+          adUnitCodes: ['au1', 'au2']
         }));
       });