added test for constraints

Author: transistive

tests/Integration/ComplexQueryTest.php

@@ -13,7 +13,10 @@
 
 namespace Laudis\Neo4j\Tests\Integration;
 
+use Bolt\error\MessageException;
 use Generator;
+use Laudis\Neo4j\Basic\Driver;
+use Throwable;
 use function getenv;
 use InvalidArgumentException;
 use Laudis\Neo4j\ClientBuilder;
@@ -470,6 +473,24 @@ public function testTimeoutRecovery(string $alias): void
         $tsx->run('CALL apoc.util.sleep(20000)');
     }
 
+    /**
+     * @dataProvider connectionAliases
+     */
+    public function testConstraintHandling(string $alias): void
+    {
+        $session = $this->getClient()->getDriver($alias)->createSession();
+
+        $session->run("CREATE (test:Test{id: '123'})");
+        try {
+            $session->run('CREATE CONSTRAINT ON (test:Test) ASSERT test.id IS UNIQUE');
+        } catch (Throwable $e) {
+            // We cannot use IF EXISTS on version 4.0
+            $session->run('DROP CONSTRAINT ON (test:Test) ASSERT test.id IS UNIQUE');
+        }
+        $this->expectException(MessageException::class);
+        $session->run("CREATE (test:Test {id: '123'}) RETURN test");
+    }
+
     /**
      * @dataProvider connectionAliases
      */