From 256cedd9ece42f4b0e848f7cea0697c0beff426c Mon Sep 17 00:00:00 2001
From: siimm <siim.medijainen@vaimo.com>
Date: Wed, 2 Sep 2020 11:04:53 +0000
Subject: [PATCH 1/3] ensure tags uniqueness

---
 lib/internal/Magento/Framework/Indexer/CacheContext.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/internal/Magento/Framework/Indexer/CacheContext.php b/lib/internal/Magento/Framework/Indexer/CacheContext.php
index 4a6964477ebd5..1374a8c3f2089 100644
--- a/lib/internal/Magento/Framework/Indexer/CacheContext.php
+++ b/lib/internal/Magento/Framework/Indexer/CacheContext.php
@@ -73,6 +73,6 @@ public function getIdentities()
                 $identities[] = $cacheTag . '_' . $id;
             }
         }
-        return array_merge($identities, array_unique($this->tags));
+        return array_unique(array_merge($identities, array_unique($this->tags));
     }
 }

From f17148f902309ddfd6868b17b7183099222084d8 Mon Sep 17 00:00:00 2001
From: siimm <siim.medijainen@vaimo.com>
Date: Fri, 4 Sep 2020 08:25:34 +0000
Subject: [PATCH 2/3] add simple unit test for #29890

---
 .../Indexer/Test/Unit/CacheContextTest.php    | 59 +++++++++++++++++++
 1 file changed, 59 insertions(+)
 create mode 100644 lib/internal/Magento/Framework/Indexer/Test/Unit/CacheContextTest.php

diff --git a/lib/internal/Magento/Framework/Indexer/Test/Unit/CacheContextTest.php b/lib/internal/Magento/Framework/Indexer/Test/Unit/CacheContextTest.php
new file mode 100644
index 0000000000000..90606435a4487
--- /dev/null
+++ b/lib/internal/Magento/Framework/Indexer/Test/Unit/CacheContextTest.php
@@ -0,0 +1,59 @@
+<?php
+
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\Framework\Indexer\Test\Unit;
+
+use Magento\Framework\Indexer\CacheContext;
+use PHPUnit\Framework\TestCase;
+
+class CacheContextTest extends TestCase
+{
+    /**
+     * @var Batch
+     */
+    private $object;
+
+    protected function setUp(): void
+    {
+        $this->object = new CacheContext();
+    }
+
+    /**
+     * @param array $tagsData
+     * @param array $expected
+     * @dataProvider getTagsDataProvider
+     */
+    public function testUniqueTags($tagsData, $expected)
+    {
+        foreach ($tagsData as $tagSet) {
+            foreach ($tagSet as $cacheTag => $ids) {
+                $this->object->registerEntities($cacheTag, $ids);
+            }
+        }
+
+        $this->assertEquals($this->object->getIdentities(), $expected);
+    }
+
+    /**
+     * @return array
+     */
+    public function getTagsDataProvider()
+    {
+        return [
+            'same entities and ids' => [
+                [['cat_p' => [1]], ['cat_p' => [1]]],
+                ['cat_p_1']
+            ],
+            'same entities with overlapping ids' => [
+                [['cat_p' => [1, 2, 3]], ['cat_p' => [3]]],
+                ['cat_p_1', 'cat_p_2', 'cat_p_3']
+            ]
+        ];
+    }
+}
+

From 47761ec37af3422a807faf9ce52e682502832502 Mon Sep 17 00:00:00 2001
From: siimm <siim.medijainen@vaimo.com>
Date: Sun, 6 Sep 2020 19:55:52 +0000
Subject: [PATCH 3/3] fix typo, remove empty line in test

---
 lib/internal/Magento/Framework/Indexer/CacheContext.php         | 2 +-
 .../Magento/Framework/Indexer/Test/Unit/CacheContextTest.php    | 1 -
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/internal/Magento/Framework/Indexer/CacheContext.php b/lib/internal/Magento/Framework/Indexer/CacheContext.php
index 1374a8c3f2089..b29aafa054997 100644
--- a/lib/internal/Magento/Framework/Indexer/CacheContext.php
+++ b/lib/internal/Magento/Framework/Indexer/CacheContext.php
@@ -73,6 +73,6 @@ public function getIdentities()
                 $identities[] = $cacheTag . '_' . $id;
             }
         }
-        return array_unique(array_merge($identities, array_unique($this->tags));
+        return array_unique(array_merge($identities, array_unique($this->tags)));
     }
 }
diff --git a/lib/internal/Magento/Framework/Indexer/Test/Unit/CacheContextTest.php b/lib/internal/Magento/Framework/Indexer/Test/Unit/CacheContextTest.php
index 90606435a4487..a13d5d54aafe7 100644
--- a/lib/internal/Magento/Framework/Indexer/Test/Unit/CacheContextTest.php
+++ b/lib/internal/Magento/Framework/Indexer/Test/Unit/CacheContextTest.php
@@ -56,4 +56,3 @@ public function getTagsDataProvider()
         ];
     }
 }
-