Make sure the plugins can use InstalledVersions to introspect themselves when being activated right after initial install

src/Composer/Installer/InstallationManager.php

@@ -467,7 +467,11 @@ class InstallationManager
     {
         $package = $operation->getPackage();
         $installer = $this->getInstaller($package->getType());
+        if ($installer instanceof PluginInstaller) {
+            $promise = $installer->install($repo, $package, $this);
+        } else {
             $promise = $installer->install($repo, $package);
+        }
         $this->markForNotification($package);
 
         return $promise;
@@ -489,7 +493,11 @@ class InstallationManager
 
         if ($initialType === $targetType) {
             $installer = $this->getInstaller($initialType);
+            if ($installer instanceof PluginInstaller) {
+                $promise = $installer->update($repo, $initial, $target, $this);
+            } else {
                 $promise = $installer->update($repo, $initial, $target);
+            }
             $this->markForNotification($target);
         } else {
             $promise = $this->getInstaller($initialType)->uninstall($repo, $initial);
@@ -497,8 +505,12 @@ class InstallationManager
                 $promise = \React\Promise\resolve();
             }
 
+            $installManager = $this;
             $installer = $this->getInstaller($targetType);
-            $promise->then(function () use ($installer, $repo, $target) {
+            $promise->then(function () use ($installer, $repo, $target, $installManager) {
+                if ($installer instanceof PluginInstaller) {
+                    return $installer->install($repo, $target, $installManager);
+                }
                 return $installer->install($repo, $target);
             });
         }

src/Composer/Installer/PluginInstaller.php

@@ -17,6 +17,7 @@ use Composer\IO\IOInterface;
 use Composer\Repository\InstalledRepositoryInterface;
 use Composer\Package\PackageInterface;
 use Composer\Util\Filesystem;
+use Composer\Installer\InstallationManager;
 use React\Promise\PromiseInterface;
 
 /**
@@ -62,7 +63,7 @@ class PluginInstaller extends LibraryInstaller
     /**
      * {@inheritDoc}
      */
-    public function install(InstalledRepositoryInterface $repo, PackageInterface $package)
+    public function install(InstalledRepositoryInterface $repo, PackageInterface $package, InstallationManager $installationManager = null)
     {
         $promise = parent::install($repo, $package);
         if (!$promise instanceof PromiseInterface) {
@@ -72,8 +73,11 @@ class PluginInstaller extends LibraryInstaller
         $pluginManager = $this->composer->getPluginManager();
         $self = $this;
 
-        return $promise->then(function () use ($self, $pluginManager, $package, $repo) {
+        return $promise->then(function () use ($self, $pluginManager, $package, $repo, $installationManager) {
             try {
+                if ($installationManager) {
+                    $self->updateInstalledVersions($repo, $installationManager);
+                }
                 $pluginManager->registerPackage($package, true);
             } catch (\Exception $e) {
                 $self->rollbackInstall($e, $repo, $package);
@@ -84,7 +88,7 @@ class PluginInstaller extends LibraryInstaller
     /**
      * {@inheritDoc}
      */
-    public function update(InstalledRepositoryInterface $repo, PackageInterface $initial, PackageInterface $target)
+    public function update(InstalledRepositoryInterface $repo, PackageInterface $initial, PackageInterface $target, InstallationManager $installationManager = null)
     {
         $promise = parent::update($repo, $initial, $target);
         if (!$promise instanceof PromiseInterface) {
@@ -94,9 +98,12 @@ class PluginInstaller extends LibraryInstaller
         $pluginManager = $this->composer->getPluginManager();
         $self = $this;
 
-        return $promise->then(function () use ($self, $pluginManager, $initial, $target, $repo) {
+        return $promise->then(function () use ($self, $pluginManager, $initial, $target, $repo, $installationManager) {
             try {
                 $pluginManager->deactivatePackage($initial, true);
+                if ($installationManager) {
+                    $self->updateInstalledVersions($repo, $installationManager);
+                }
                 $pluginManager->registerPackage($target, true);
             } catch (\Exception $e) {
                 $self->rollbackInstall($e, $repo, $target);
@@ -121,4 +128,16 @@ class PluginInstaller extends LibraryInstaller
         parent::uninstall($repo, $package);
         throw $e;
     }
+
+    /**
+     * TODO v3 should make this private once we can drop PHP 5.3 support
+     * @private
+     */
+    public function updateInstalledVersions(InstalledRepositoryInterface $repo, InstallationManager $installationManager)
+    {
+        $versions = $repo->generateInstalledVersions($installationManager);
+        if ($versions) {
+            \Composer\InstalledVersions::reload($versions);
+        }
+    }
 }

src/Composer/Repository/FilesystemRepository.php

@@ -123,7 +123,32 @@ class FilesystemRepository extends WritableArrayRepository
 
         $this->file->write($data);
 
+
         if ($this->dumpVersions) {
+            $versions = $this->generateInstalledVersions($installationManager);
+
+            $fs->filePutContentsIfModified($repoDir.'/installed.php', '<?php return '.var_export($versions, true).';'."\n");
+            $installedVersionsClass = file_get_contents(__DIR__.'/../InstalledVersions.php');
+            // while not strictly needed since https://github.com/composer/composer/pull/9635 - we keep this for BC
+            // and overall broader compatibility with people that may not use Composer's ClassLoader. They can
+            // simply include InstalledVersions.php manually and have it working in a basic way.
+            $installedVersionsClass = str_replace('private static $installed;', 'private static $installed = '.var_export($versions, true).';', $installedVersionsClass);
+            $fs->filePutContentsIfModified($repoDir.'/InstalledVersions.php', $installedVersionsClass);
+
+            \Composer\InstalledVersions::reload($versions);
+        }
+    }
+
+    /**
+     * @return ?array
+     * @internal
+     */
+    public function generateInstalledVersions(InstallationManager $installationManager)
+    {
+        if (!$this->dumpVersions) {
+            return null;
+        }
+
         $versions = array('versions' => array());
         $packages = $this->getPackages();
         $packages[] = $rootPackage = $this->rootPackage;
@@ -202,21 +227,6 @@ class FilesystemRepository extends WritableArrayRepository
         ksort($versions['versions']);
         ksort($versions);
 
-            $fs->filePutContentsIfModified($repoDir.'/installed.php', '<?php return '.var_export($versions, true).';'."\n");
+        return $versions;
-            $installedVersionsClass = file_get_contents(__DIR__.'/../InstalledVersions.php');
-            // while not strictly needed since https://github.com/composer/composer/pull/9635 - we keep this for BC
-            // and overall broader compatibility with people that may not use Composer's ClassLoader. They can
-            // simply include InstalledVersions.php manually and have it working in a basic way.
-            $installedVersionsClass = str_replace('private static $installed;', 'private static $installed = '.var_export($versions, true).';', $installedVersionsClass);
-            $fs->filePutContentsIfModified($repoDir.'/InstalledVersions.php', $installedVersionsClass);
-
-            // make sure the InstalledVersions class is loaded and has the latest state
-            // not using the autoloader here to avoid loading the one from Composer's vendor dir
-            if (!class_exists('Composer\InstalledVersions', false)) {
-                include $repoDir.'/InstalledVersions.php';
-            } else {
-                \Composer\InstalledVersions::reload($versions);
-            }
-        }
     }
 }