Load Symfony polyfill packages when running the plugin

src/ComposerPlugin.php

@@ -15,7 +15,7 @@ final class ComposerPlugin implements PluginInterface, Capable
 {
     public function activate(Composer $composer, IOInterface $io)
     {
-
+        PolyfillLoader::load($composer, $io);
     }
 
     public function deactivate(Composer $composer, IOInterface $io)

src/PolyfillLoader.php

@@ -0,0 +1,49 @@
+<?php
+
+namespace Cs278\ComposerAudit;
+
+use Composer\Composer;
+use Composer\IO\IOInterface;
+
+/**
+ * Find Symfony Polyfill libraries and loads them.
+ */
+final class PolyfillLoader
+{
+    public static function load(Composer $composer, IOInterface $io)
+    {
+        $packages = $composer->getRepositoryManager()->getLocalRepository()->getPackages();
+        $includeFiles = [];
+
+        foreach ($packages as $package) {
+            if (strpos($package->getName(), 'symfony/polyfill-') === 0) {
+                $io->debug(sprintf('PolyfillLoader finding files in: %s', $package->getName()));
+                $autoload = $package->getAutoload();
+
+                if (isset($autoload['files'])) {
+                    $installPath = $composer->getInstallationManager()->getInstallPath($package);
+
+                    foreach ($autoload['files'] as $file) {
+                        $io->debug(sprintf('PolyfillLoader found: %s %s', $package->getName(), $file));
+                        $includeFiles[] = $installPath.\DIRECTORY_SEPARATOR.$file;
+                    }
+                }
+            }
+        }
+
+        foreach ($includeFiles as $includeFile) {
+            if (in_array($includeFile, \get_included_files(), true)) {
+                $io->debug(sprintf('PolyfillLoader %s is already loaded', $includeFile));
+                return;
+            }
+
+            $io->debug(sprintf('PolyfillLoader loading: %s', $includeFile));
+            self::incldueFile($includeFile);
+        }
+    }
+
+    private static function incldueFile($path): void
+    {
+        require $path;
+    }
+}