Make sure if plugins depend on the root package that the root package is also autoloaded correctly, refs #9530

src/Composer/Plugin/PluginManager.php

@@ -21,6 +21,7 @@ use Composer\Package\RootPackage;
 use Composer\Package\Version\VersionParser;
 use Composer\Repository\RepositoryInterface;
 use Composer\Repository\InstalledRepository;
+use Composer\Repository\RootPackageRepository;
 use Composer\Package\PackageInterface;
 use Composer\Package\Link;
 use Composer\Semver\Constraint\Constraint;
@@ -174,7 +175,8 @@ class PluginManager
         $localRepo = $this->composer->getRepositoryManager()->getLocalRepository();
         $globalRepo = $this->globalComposer ? $this->globalComposer->getRepositoryManager()->getLocalRepository() : null;
 
-        $installedRepo = new InstalledRepository(array($localRepo));
+        $rootPackageRepo = new RootPackageRepository($this->composer->getPackage());
+        $installedRepo = new InstalledRepository(array($localRepo, $rootPackageRepo));
         if ($globalRepo) {
             $installedRepo->addRepository($globalRepo);
         }
@@ -185,11 +187,15 @@ class PluginManager
         $generator = $this->composer->getAutoloadGenerator();
         $autoloads = array();
         foreach ($autoloadPackages as $autoloadPackage) {
-            $downloadPath = $this->getInstallPath($autoloadPackage, $globalRepo && $globalRepo->hasPackage($autoloadPackage));
+            if ($autoloadPackage === $this->composer->getPackage()) {
+                $downloadPath = '';
+            } else {
+                $downloadPath = $this->getInstallPath($autoloadPackage, $globalRepo && $globalRepo->hasPackage($autoloadPackage));
+            }
             $autoloads[] = array($autoloadPackage, $downloadPath);
         }
 
-        $map = $generator->parseAutoloads($autoloads, new RootPackage('dummy/root-package', '1.0.0.0', '1.0.0'));
+        $map = $generator->parseAutoloads($autoloads, $this->composer->getPackage());
         $classLoader = $generator->createLoader($map);
         $classLoader->register();