From 3aa06cf92890f88e90e99fecf041dc54f26c1a57 Mon Sep 17 00:00:00 2001
From: Chris Smith <chris.smith@widerplan.com>
Date: Tue, 27 Jul 2021 12:51:03 +0100
Subject: [PATCH 1/3] Allow tests to be run against system Composer

---
 tests/integration/IntegrationTest.php | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/tests/integration/IntegrationTest.php b/tests/integration/IntegrationTest.php
index 39bde77..999b6a5 100644
--- a/tests/integration/IntegrationTest.php
+++ b/tests/integration/IntegrationTest.php
@@ -93,8 +93,17 @@ public function testRun(int $expectedExit, string $expectedOutput, string $condi
         }
 
         $workingDir = temporaryDir();
-        $composer = function (...$args) use ($workingDir) {
-            array_unshift($args, getcwd().'/vendor/bin/composer');
+
+        // Environment variable instructs tests to use another Composer binary,
+        // this allows testing with the systems Composer installation.
+        $composerBin = getenv('COMPOSER_AUDIT_TEST_COMPOSER_BINARY');
+
+        if (!is_string($composerBin) || is_dir($composerBin) || !is_executable($composerBin)) {
+            $composerBin = getcwd().'/vendor/bin/composer';
+        }
+
+        $composer = function (...$args) use ($composerBin, $workingDir) {
+            array_unshift($args, $composerBin);
 
             return new Process($args, $workingDir, [
                 'COMPOSER_HOME' => $workingDir.'/.composer',

From 60bcc4eea2b2af679df5bbc527221bdf15eb2bb5 Mon Sep 17 00:00:00 2001
From: Chris Smith <chris.smith@widerplan.com>
Date: Tue, 27 Jul 2021 13:25:09 +0100
Subject: [PATCH 2/3] Test against local and system Composer

---
 .github/workflows/main.yml | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 979e887..9275967 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -52,7 +52,13 @@ jobs:
         run: |
           vendor/bin/simple-phpunit --version | head -n1 >&2
 
-          vendor/bin/simple-phpunit --verbose $args
+          echo "::group::Tests (w/ source composer/composer)"
+          vendor/bin/simple-phpunit --verbose
+          echo "::endgroup::"
+
+          echo "::group::Tests (w/ phar composer/composer)"
+          COMPOSER_AUDIT_TEST_COMPOSER_BINARY=$(which composer) vendor/bin/simple-phpunit --verbose
+          echo "::endgroup::"
   # Verifies that the plugin entry point still parses on PHP 5.3, users of 5.3
   # cannot use this Composer plugin but at least it won't break their Composer.
   legacy:

From 305eb3c21735fa56c56c4732845b21ff509f14b2 Mon Sep 17 00:00:00 2001
From: Chris Smith <chris.smith@widerplan.com>
Date: Tue, 27 Jul 2021 14:17:06 +0100
Subject: [PATCH 3/3] Load Symfony polyfill packages when running the plugin

---
 src/ComposerPlugin.php |  2 +-
 src/PolyfillLoader.php | 49 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+), 1 deletion(-)
 create mode 100644 src/PolyfillLoader.php

diff --git a/src/ComposerPlugin.php b/src/ComposerPlugin.php
index 5530670..a4dfd7a 100644
--- a/src/ComposerPlugin.php
+++ b/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)
diff --git a/src/PolyfillLoader.php b/src/PolyfillLoader.php
new file mode 100644
index 0000000..c5c0a1a
--- /dev/null
+++ b/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;
+    }
+}