Port fix from #1272

Author: spawnia

CHANGELOG.md

@@ -101,7 +101,6 @@ You can find and compare releases at the [GitHub release page](https://github.co
 - Avoid calling defined functions named like lazily loaded types
 - Show actual error in debug entries
 - Deal with `iterable` in implementations of `PromiseAdapter::all()`
-- Accept AST where field arguments are not given
 
 ### Removed
 

src/Executor/Values.php

@@ -183,8 +183,11 @@ public static function getArgumentValues($def, Node $node, ?array $variableValue
         /** @var array<string, ArgumentNodeValue> $argumentValueMap */
         $argumentValueMap = [];
 
-        foreach ($node->arguments as $argumentNode) {
-            $argumentValueMap[$argumentNode->name->value] = $argumentNode->value;
+        // Might not be defined when an AST from JS is used
+        if (isset($node->arguments)) {
+            foreach ($node->arguments as $argumentNode) {
+                $argumentValueMap[$argumentNode->name->value] = $argumentNode->value;
+            }
         }
 
         return static::getArgumentValuesForMap($def, $argumentValueMap, $variableValues, $node);