Refactoring queryfield input field management

Author: moufmouf

src/QueryField.php

@@ -7,11 +7,14 @@
 use GraphQL\Type\Definition\FieldDefinition;
 use GraphQL\Type\Definition\IDType;
 use GraphQL\Type\Definition\InputObjectType;
+use GraphQL\Type\Definition\InputType;
 use GraphQL\Type\Definition\ListOfType;
 use GraphQL\Type\Definition\NonNull;
 use GraphQL\Type\Definition\OutputType;
 use GraphQL\Type\Definition\ScalarType;
 use GraphQL\Type\Definition\Type;
+use InvalidArgumentException;
+use function is_array;
 use TheCodingMachine\GraphQL\Controllers\Hydrators\HydratorInterface;
 use TheCodingMachine\GraphQL\Controllers\Types\DateTimeType;
 use TheCodingMachine\GraphQL\Controllers\Types\ID;
@@ -52,30 +55,7 @@ public function __construct(string $name, OutputType $type, array $arguments, ?c
             foreach ($arguments as $name => $arr) {
                 $type = $arr['type'];
                 if (isset($args[$name])) {
-                    $val = $args[$name];
-
-                    $type = $this->stripNonNullType($type);
-                    if ($type instanceof ListOfType) {
-                        $subtype = $this->stripNonNullType($type->getWrappedType());
-                        $val = array_map(function ($item) use ($subtype, $hydrator) {
-                            if ($subtype instanceof DateTimeType) {
-                                return new \DateTimeImmutable($item);
-                            } elseif ($subtype instanceof ID) {
-                                return new ID($item);
-                            } elseif ($subtype instanceof InputObjectType) {
-                                return $hydrator->hydrate($item, $subtype);
-                            }
-                            return $item;
-                        }, $val);
-                    } elseif ($type instanceof DateTimeType) {
-                        $val = new \DateTimeImmutable($val);
-                    } elseif ($type instanceof IDType) {
-                        $val = new ID($val);
-                    } elseif ($type instanceof InputObjectType) {
-                        $val = $hydrator->hydrate($val, $type);
-                    } elseif (!$type instanceof ScalarType) {
-                        throw new \RuntimeException('Unexpected type: '.get_class($type));
-                    }
+                    $val = $this->castVal($args[$name], $type, $hydrator);
                 } elseif (array_key_exists('defaultValue', $arr)) {
                     $val = $arr['defaultValue'];
                 } else {
@@ -106,4 +86,33 @@ private function stripNonNullType(Type $type): Type
         }
         return $type;
     }
+
+    /**
+     * Casts a value received from GraphQL into an argument passed to a method.
+     *
+     * @param mixed $val
+     * @param InputType $type
+     * @return mixed
+     */
+    private function castVal($val, InputType $type, HydratorInterface $hydrator)
+    {
+        $type = $this->stripNonNullType($type);
+        if ($type instanceof ListOfType) {
+            if (!is_array($val)) {
+                throw new InvalidArgumentException('Expected GraphQL List but value passed is not an array.');
+            }
+            return array_map(function($item) use ($type, $hydrator) {
+                return $this->castVal($item, $type->getWrappedType(), $hydrator);
+            }, $val);
+        } elseif ($type instanceof DateTimeType) {
+            return new \DateTimeImmutable($val);
+        } elseif ($type instanceof IDType) {
+            return new ID($val);
+        } elseif ($type instanceof InputObjectType) {
+            return $hydrator->hydrate($val, $type);
+        } elseif (!$type instanceof ScalarType) {
+            throw new \RuntimeException('Unexpected type: '.get_class($type));
+        }
+        return $val;
+    }
 }

src/Types/ID.php

@@ -2,6 +2,7 @@
 namespace TheCodingMachine\GraphQL\Controllers\Types;
 
 
+use InvalidArgumentException;
 use TheCodingMachine\GraphQL\Controllers\GraphQLException;
 
 /**
@@ -14,7 +15,7 @@ class ID
     public function __construct($value)
     {
         if (! is_scalar($value) && (! is_object($value) || ! method_exists($value, '__toString'))) {
-            throw new GraphQLException('ID constructor cannot be passed a non scalar value.');
+            throw new InvalidArgumentException('ID constructor cannot be passed a non scalar value.');
         }
         $this->value = $value;
     }

tests/Types/IDTest.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace TheCodingMachine\GraphQL\Controllers\Types;
+
+use InvalidArgumentException;
+use PHPUnit\Framework\TestCase;
+use stdClass;
+
+class IDTest extends TestCase
+{
+    public function testConstructException()
+    {
+        $this->expectException(InvalidArgumentException::class);
+        new ID(new stdClass());
+    }
+
+    public function testVal()
+    {
+        $id = new ID(42);
+        $this->assertSame(42, $id->val());
+        $this->assertSame('42', (string) $id);
+    }
+}