[12.x] Table prefix not applied when cloning connections

src/Illuminate/Database/Connection.php

@@ -232,6 +232,24 @@ public function __construct($pdo, $database = '', $tablePrefix = '', array $conf
         $this->useDefaultPostProcessor();
     }
 
+    /**
+     * Prepare the instance for cloning.
+     *
+     * @return void
+     */
+    public function __clone()
+    {
+        // When cloning, we need to re-initialize the grammars and post processor
+        // so they reference the cloned connection instead of the original.
+        $this->queryGrammar = $this->getDefaultQueryGrammar();
+
+        $this->postProcessor = $this->getDefaultPostProcessor();
+
+        if (! is_null($this->schemaGrammar)) {
+            $this->useDefaultSchemaGrammar();
+        }
+    }
+
     /**
      * Set the query grammar to the default implementation.
      *

tests/Database/DatabaseEloquentIntegrationWithTablePrefixTest.php

@@ -93,6 +93,53 @@ public function testBasicModelHydration()
         $this->assertCount(1, $models);
     }
 
+    public function testTablePrefixWithClonedConnection()
+    {
+        $originalConnection = $this->connection();
+        $originalPrefix = $originalConnection->getTablePrefix();
+
+        $clonedConnection = clone $originalConnection;
+        $clonedConnection->setTablePrefix('cloned_');
+
+        $this->assertSame($originalPrefix, $originalConnection->getTablePrefix());
+        $this->assertSame('cloned_', $clonedConnection->getTablePrefix());
+
+        $clonedConnection->getSchemaBuilder()->create('test_table', function ($table) {
+            $table->increments('id');
+            $table->string('name');
+        });
+
+        $this->assertTrue($clonedConnection->getSchemaBuilder()->hasTable('test_table'));
+        $query = $clonedConnection->table('test_table')->toSql();
+        $this->assertStringContainsString('cloned_test_table', $query);
+
+        $clonedConnection->getSchemaBuilder()->drop('test_table');
+    }
+
+    public function testQueryGrammarUsesCorrectPrefixAfterCloning()
+    {
+        $originalConnection = $this->connection();
+
+        $clonedConnection = clone $originalConnection;
+        $clonedConnection->setTablePrefix('new_prefix_');
+
+        $selectSql = $clonedConnection->table('users')->toSql();
+        $this->assertStringContainsString('new_prefix_users', $selectSql);
+
+        $insertSql = $clonedConnection->table('users')->toSql();
+        $this->assertStringContainsString('new_prefix_users', $insertSql);
+
+        $updateSql = $clonedConnection->table('users')->where('id', 1)->toSql();
+        $this->assertStringContainsString('new_prefix_users', $updateSql);
+
+        $deleteSql = $clonedConnection->table('users')->where('id', 1)->toSql();
+        $this->assertStringContainsString('new_prefix_users', $deleteSql);
+
+        $originalSql = $originalConnection->table('users')->toSql();
+        $this->assertStringContainsString('prefix_users', $originalSql);
+        $this->assertStringNotContainsString('new_prefix_users', $originalSql);
+    }
+
     /**
      * Helpers...
      */