From 8394e3a66e3248f66a8a4a071b145b1a34ff2894 Mon Sep 17 00:00:00 2001
From: Leo <losoviz@gmail.com>
Date: Sat, 4 Apr 2020 14:29:19 +0800
Subject: [PATCH 1/3] Throw exception if variable is undeclared

---
 src/Execution/Request.php | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/Execution/Request.php b/src/Execution/Request.php
index 5b3da1a0..88b7be72 100644
--- a/src/Execution/Request.php
+++ b/src/Execution/Request.php
@@ -66,6 +66,13 @@ public function __construct($data = [], $variables = [])
                 if (!array_key_exists($ref->getName(), $variables)) {
                     /** @var Variable $variable */
                     $variable = $ref->getVariable();
+                    /**
+                     * If $variable is null, then it was not declared in the operation arguments
+                     * @see https://graphql.org/learn/queries/#variables
+                     */
+                    if (is_null($variable)) {
+                        throw new InvalidRequestException(sprintf("Variable %s hasn't been declared", $ref->getName()), $ref->getLocation());
+                    }
                     if ($variable->hasDefaultValue()) {
                         $variables[$variable->getName()] = $variable->getDefaultValue()->getValue();
                         continue;

From 4e9c094228c3253a970b098dc3206c9a75f9df1c Mon Sep 17 00:00:00 2001
From: Leo <losoviz@gmail.com>
Date: Sun, 12 Apr 2020 15:46:05 +0800
Subject: [PATCH 2/3] Added test

---
 tests/Issues/Issue238/Issue238Test.php | 57 ++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 tests/Issues/Issue238/Issue238Test.php

diff --git a/tests/Issues/Issue238/Issue238Test.php b/tests/Issues/Issue238/Issue238Test.php
new file mode 100644
index 00000000..3cd96179
--- /dev/null
+++ b/tests/Issues/Issue238/Issue238Test.php
@@ -0,0 +1,57 @@
+<?php
+
+namespace Youshido\Tests\Issue194;
+
+use PHPUnit\Framework\TestCase;
+use Youshido\GraphQL\Schema\Schema;
+use Youshido\GraphQL\Execution\Processor;
+use Youshido\GraphQL\Type\Scalar\IntType;
+use Youshido\GraphQL\Execution\ResolveInfo;
+use Youshido\GraphQL\Type\Object\ObjectType;
+use Youshido\GraphQL\Type\Scalar\StringType;
+
+class Issue238Test extends TestCase
+{
+    public function testNotDefinedVariableThrowsException()
+    {
+        $schema = new Schema([
+            'query' => new ObjectType([
+                'name'   => 'RootQuery',
+                'fields' => [
+                    'currentUser' => [
+                        'type'    => new StringType(),
+                        'args'    => [
+                            'age' => [
+                                'type'         => new IntType(),
+                                'defaultValue' => 20,
+                            ],
+                        ],
+                        'resolve' => static function ($source, $args, ResolveInfo $info) {
+                            return 'Alex age ' . $args['age'];
+                        },
+                    ],
+                ],
+            ]),
+        ]);
+
+        $processor = new Processor($schema);
+
+        /**
+         * If using a variable in a query, it must be defined in the operation
+         * $properQuery = 'query GetUserAge($age:Int) { currentUser(age:$age) }';
+         * When not declaring the variable in the operation, it must return a nice error message
+         * (instead of throwing a RuntimeException)
+         */
+        $unproperQuery = '{ currentUser(age:$age) }';
+        $response = $processor->processPayload($unproperQuery)->getResponseData();
+        if ($this->assertArrayHasKey(
+            'errors',
+            $response
+        )) {
+            $this->assertArraySubset(
+                ['message' => 'Variable age hasn\'t been declared'],
+                $response['errors']
+            );
+        }
+    }
+}

From 070b53705940d3005dd2626b4ac4970bd7ddf473 Mon Sep 17 00:00:00 2001
From: Leo <losoviz@gmail.com>
Date: Sun, 12 Apr 2020 16:34:25 +0800
Subject: [PATCH 3/3] Fixed namespace

---
 tests/Issues/Issue238/Issue238Test.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/Issues/Issue238/Issue238Test.php b/tests/Issues/Issue238/Issue238Test.php
index 3cd96179..934d1e37 100644
--- a/tests/Issues/Issue238/Issue238Test.php
+++ b/tests/Issues/Issue238/Issue238Test.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Youshido\Tests\Issue194;
+namespace Youshido\Tests\Issue238;
 
 use PHPUnit\Framework\TestCase;
 use Youshido\GraphQL\Schema\Schema;