From ea30392105a769c18af62891a02d3e679502010d Mon Sep 17 00:00:00 2001
From: Franz Liedke <franz@develophp.org>
Date: Tue, 23 Feb 2016 23:06:21 +0900
Subject: [PATCH 1/2] RepositoryManager::prependRepository()

This method is useful for dynamically adding repositories with
higher priority than Packagist, e.g. from a Composer plugin.
---
 src/Composer/Repository/RepositoryManager.php | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/Composer/Repository/RepositoryManager.php b/src/Composer/Repository/RepositoryManager.php
index 05dcc1b4a..649c66cd9 100644
--- a/src/Composer/Repository/RepositoryManager.php
+++ b/src/Composer/Repository/RepositoryManager.php
@@ -89,6 +89,18 @@ class RepositoryManager
         $this->repositories[] = $repository;
     }
 
+    /**
+     * Adds a repository to the beginning of the chain
+     *
+     * This is useful when injecting additional repositories that should trump Packagist, e.g. from a plugin.
+     *
+     * @param RepositoryInterface $repository repository instance
+     */
+    public function prependRepository(RepositoryInterface $repository)
+    {
+        array_unshift($this->repositories, $repository);
+    }
+
     /**
      * Returns a new repository for a specific installation type.
      *

From f47c2c9ed7aca48473243bf1204261797d696aab Mon Sep 17 00:00:00 2001
From: Franz Liedke <franz@develophp.org>
Date: Wed, 24 Feb 2016 00:57:10 +0900
Subject: [PATCH 2/2] Add test case for RepositoryManager::prependRepository
 method

---
 .../Test/Repository/RepositoryManagerTest.php    | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/tests/Composer/Test/Repository/RepositoryManagerTest.php b/tests/Composer/Test/Repository/RepositoryManagerTest.php
index 13e51fb18..bedd07f8e 100644
--- a/tests/Composer/Test/Repository/RepositoryManagerTest.php
+++ b/tests/Composer/Test/Repository/RepositoryManagerTest.php
@@ -32,6 +32,22 @@ class RepositoryManagerTest extends TestCase
         }
     }
 
+    public function testPrepend()
+    {
+        $rm = new RepositoryManager(
+            $this->getMock('Composer\IO\IOInterface'),
+            $this->getMock('Composer\Config'),
+            $this->getMockBuilder('Composer\EventDispatcher\EventDispatcher')->disableOriginalConstructor()->getMock()
+        );
+
+        $repository1 = $this->getMock('Composer\Repository\RepositoryInterface');
+        $repository2 = $this->getMock('Composer\Repository\RepositoryInterface');
+        $rm->addRepository($repository1);
+        $rm->prependRepository($repository2);
+
+        $this->assertEquals(array($repository2, $repository1), $rm->getRepositories());
+    }
+
     /**
      * @dataProvider creationCases
      */