From 76e182e6166c1ebf83dd85eb4f6199eb0fb56be8 Mon Sep 17 00:00:00 2001
From: Vladimir Razuvaev <vladimir.razuvaev@gmail.com>
Date: Tue, 4 Jul 2017 13:59:46 +0700
Subject: [PATCH] Forbid duplicate type definitions

---
 src/Utils/BuildSchema.php       | 12 +++++++++++-
 tests/Utils/BuildSchemaTest.php | 24 ++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/src/Utils/BuildSchema.php b/src/Utils/BuildSchema.php
index 4eea21f..4601628 100644
--- a/src/Utils/BuildSchema.php
+++ b/src/Utils/BuildSchema.php
@@ -112,8 +112,12 @@ class BuildSchema
                 case NodeKind::ENUM_TYPE_DEFINITION:
                 case NodeKind::UNION_TYPE_DEFINITION:
                 case NodeKind::INPUT_OBJECT_TYPE_DEFINITION:
+                    $typeName = $d->name->value;
+                    if (!empty($this->nodeMap[$typeName])) {
+                        throw new Error("Type \"$typeName\" was defined more than once.");
+                    }
                     $typeDefs[] = $d;
-                    $this->nodeMap[$d->name->value] = $d;
+                    $this->nodeMap[$typeName] = $d;
                     break;
                 case NodeKind::DIRECTIVE_DEFINITION:
                     $directiveDefs[] = $d;
@@ -453,6 +457,12 @@ class BuildSchema
         ]);
     }
 
+    /**
+     * Given a collection of directives, returns the string value for the
+     * deprecation reason.
+     *
+     * @param $directives
+     */
     private function getDeprecationReason($directives)
     {
         $deprecatedAST = $directives ? Utils::find(
diff --git a/tests/Utils/BuildSchemaTest.php b/tests/Utils/BuildSchemaTest.php
index 5c2663a..65e5fe5 100644
--- a/tests/Utils/BuildSchemaTest.php
+++ b/tests/Utils/BuildSchemaTest.php
@@ -896,4 +896,28 @@ fragment Foo on Type { field }
         $doc = Parser::parse($body);
         BuildSchema::buildAST($doc);
     }
+
+    /**
+     * @it Forbids duplicate type definitions
+     */
+    public function testForbidsDuplicateTypeDefinitions()
+    {
+        $body = '
+schema {
+  query: Repeated
+}
+
+type Repeated {
+  id: Int
+}
+
+type Repeated {
+  id: String
+}
+';
+        $doc = Parser::parse($body);
+
+        $this->setExpectedException('GraphQL\Error\Error', 'Type "Repeated" was defined more than once.');
+        BuildSchema::buildAST($doc);
+    }
 }