fix: change slug column collation to utf8mb4_bin to fix accent-sensitive uniqueness

Setup/Patch/Schema/CleanupLegacyIndexesTweakwiseAttributeSlugTable.php

@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tweakwise\Magento2Tweakwise\Setup\Patch\Schema;
+
+use Magento\Framework\Setup\Patch\SchemaPatchInterface;
+use Magento\Framework\Setup\SchemaSetupInterface;
+
+class CleanupLegacyIndexesTweakwiseAttributeSlugTable implements SchemaPatchInterface
+{
+    /**
+     * @param SchemaSetupInterface $schemaSetup
+     */
+    public function __construct(private readonly SchemaSetupInterface $schemaSetup)
+    {
+    }
+
+    /**
+     * Drop legacy indexes that were created before declarative schema took over.
+     * The declarative schema creates its own indexes with canonical names;
+     * the old ones are left behind because they were not registered in db_schema_whitelist.json.
+     *
+     * @return $this
+     */
+    public function apply(): self
+    {
+        $setup = $this->schemaSetup;
+        $setup->startSetup();
+
+        $connection = $setup->getConnection();
+        $tableName = $setup->getTable('tweakwise_attribute_slug');
+
+        $existingIndexes = array_column(
+            $connection->fetchAll('SHOW INDEX FROM ' . $connection->quoteIdentifier($tableName)),
+            'Key_name'
+        );
+
+        foreach (['ATTRIBUTE', 'STORE_SLUG'] as $indexName) {
+            if (!in_array($indexName, $existingIndexes, true)) {
+                continue;
+            }
+
+            $connection->dropIndex($tableName, $indexName);
+        }
+
+        $setup->endSetup();
+
+        return $this;
+    }
+
+    /**
+     * @return class-string[]
+     */
+    public static function getDependencies(): array
+    {
+        return [
+            AddAttributeCodeToTweakwiseAttributeSlugTable::class,
+        ];
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getAliases(): array
+    {
+        return [];
+    }
+}

Setup/Patch/Schema/SetSlugColumnCollationTweakwiseAttributeSlugTable.php

@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tweakwise\Magento2Tweakwise\Setup\Patch\Schema;
+
+use Magento\Framework\Setup\Patch\SchemaPatchInterface;
+use Magento\Framework\Setup\SchemaSetupInterface;
+
+class SetSlugColumnCollationTweakwiseAttributeSlugTable implements SchemaPatchInterface
+{
+    /**
+     * @param SchemaSetupInterface $schemaSetup
+     */
+    public function __construct(private readonly SchemaSetupInterface $schemaSetup)
+    {
+    }
+
+    /**
+     * Change the slug column to utf8mb4_bin collation so that accent-distinct slugs
+     * (e.g. "e" vs "é" after transliteration) are treated as unique by the DB index.
+     * utf8mb4_bin is chosen over utf8mb4_0900_as_cs for compatibility with MariaDB.
+     * Slugs are always lowercased ASCII after transliteration, so binary comparison
+     * is safe and equivalent to accent+case-sensitive for this data.
+     *
+     * @return $this
+     */
+    public function apply(): self
+    {
+        $setup = $this->schemaSetup;
+        $setup->startSetup();
+
+        $connection = $setup->getConnection();
+        $tableName = $connection->quoteIdentifier($setup->getTable('tweakwise_attribute_slug'));
+
+        // phpcs:disable Magento2.SQL.RawQuery.FoundRawSql -- modifyColumn() has no per-column collation support; ALTER TABLE is the only option
+        $connection->query(
+            'ALTER TABLE ' . $tableName
+            . ' MODIFY COLUMN `slug` VARCHAR(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NOT NULL'
+            . " COMMENT 'URL Slug'"
+        );
+        // phpcs:enable Magento2.SQL.RawQuery.FoundRawSql
+
+        $setup->endSetup();
+
+        return $this;
+    }
+
+    /**
+     * @return class-string[]
+     */
+    public static function getDependencies(): array
+    {
+        return [
+            CleanupLegacyIndexesTweakwiseAttributeSlugTable::class,
+        ];
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getAliases(): array
+    {
+        return [];
+    }
+}