Add test verifying only plugin deps are autoloaded (#10374)

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies.test

@@ -0,0 +1,24 @@
+--TEST--
+Checks that only plugin dependencies get their autoloading (and specifically files autoloading) rules included.
+--RUN--
+update
+--EXPECT--
+Loading composer repositories with package information
+Updating dependencies
+Lock file operations: 3 installs, 0 updates, 0 removals
+  - Locking plugin/a (1.0.0)
+  - Locking plugin/b (1.0.0)
+  - Locking regular/dep (1.0.0)
+Writing lock file
+Installing dependencies from lock file (including require-dev)
+Package operations: 3 installs, 0 updates, 0 removals
+  - Installing regular/dep (1.0.0): Mirroring from deps-pkg
+  - Installing plugin/a (1.0.0): Mirroring from plugin-a
+regular/dep files autoload initialized
+!!PluginAInit
+  - Installing plugin/b (1.0.0): Mirroring from plugin-b
+!!PluginBInit
+Generating autoload files
+
+--EXPECT-EXIT-CODE--
+0

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/composer.json

@@ -0,0 +1,16 @@
+{
+    "name": "root/pkg",
+    "version": "1.2.3",
+    "require": {
+        "plugin/b": "*",
+        "evil/pkg": "*"
+    },
+    "repositories": [
+        {"type": "path", "url": "plugin-*", "options": {"symlink": false}},
+        {"type": "path", "url": "deps-*", "options": {"symlink": false}},
+        {"type": "path", "url": "evil-*", "options": {"symlink": false}}
+    ],
+    "config": {
+        "allow-plugins": true
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/composer.lock

@@ -0,0 +1,38 @@
+{
+    "_readme": [
+        "This file locks the dependencies of your project to a known state",
+        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
+        "This file is @generated automatically"
+    ],
+    "content-hash": "4c3b9426f087ef6dc15cc81ef697f162",
+    "packages": [
+        {
+            "name": "evil/pkg",
+            "version": "1.0.0",
+            "dist": {
+                "type": "path",
+                "url": "evil-pkg",
+                "reference": "a95061d7a7e3cf4466381fd1abc504279c95b231"
+            },
+            "type": "library",
+            "autoload": {
+                "files": [
+                    "exec.php"
+                ]
+            },
+            "transport-options": {
+                "symlink": false,
+                "relative": true
+            }
+        }
+    ],
+    "packages-dev": [],
+    "aliases": [],
+    "minimum-stability": "stable",
+    "stability-flags": [],
+    "prefer-stable": false,
+    "prefer-lowest": false,
+    "platform": [],
+    "platform-dev": [],
+    "plugin-api-version": "2.2.0"
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/deps-pkg/composer.json

@@ -0,0 +1,7 @@
+{
+    "name": "regular/dep",
+    "version": "1.0.0",
+    "autoload": {
+        "files": ["exec.php"]
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/deps-pkg/exec.php

@@ -0,0 +1,3 @@
+<?php
+
+fwrite(STDERR, "regular/dep files autoload initialized\n");

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/evil-pkg/composer.json

@@ -0,0 +1,7 @@
+{
+    "name": "evil/pkg",
+    "version": "1.0.0",
+    "autoload": {
+        "files": ["exec.php"]
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/evil-pkg/exec.php

@@ -0,0 +1,5 @@
+<?php
+
+fwrite(STDERR, "Evil/pkg executed, this should not happen!\n");
+
+exit(1);

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/plugin-a/PluginA.php

@@ -0,0 +1,23 @@
+<?php
+
+use Composer\Plugin\PluginInterface;
+use Composer\Composer;
+use Composer\IO\IOInterface;
+use Composer\Json\JsonFile;
+use Composer\InstalledVersions;
+
+class PluginA implements PluginInterface
+{
+    public function activate(Composer $composer, IOInterface $io)
+    {
+        fwrite(STDERR, "!!PluginAInit\n");
+    }
+
+    public function deactivate(Composer $composer, IOInterface $io)
+    {
+    }
+
+    public function uninstall(Composer $composer, IOInterface $io)
+    {
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/plugin-a/composer.json

@@ -0,0 +1,15 @@
+{
+    "name": "plugin/a",
+    "version": "1.0.0",
+    "require": {
+        "regular/dep": "*",
+        "composer-plugin-api": "^2"
+    },
+    "autoload": {
+        "classmap": ["PluginA.php"]
+    },
+    "type": "composer-plugin",
+    "extra": {
+        "class": "PluginA"
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/plugin-b/PluginB.php

@@ -0,0 +1,23 @@
+<?php
+
+use Composer\Plugin\PluginInterface;
+use Composer\Composer;
+use Composer\IO\IOInterface;
+use Composer\Json\JsonFile;
+use Composer\InstalledVersions;
+
+class PluginB implements PluginInterface
+{
+    public function activate(Composer $composer, IOInterface $io)
+    {
+        fwrite(STDERR, "!!PluginBInit\n");
+    }
+
+    public function deactivate(Composer $composer, IOInterface $io)
+    {
+    }
+
+    public function uninstall(Composer $composer, IOInterface $io)
+    {
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/plugin-b/composer.json

@@ -0,0 +1,15 @@
+{
+    "name": "plugin/b",
+    "version": "1.0.0",
+    "require": {
+        "plugin/a": "*",
+        "composer-plugin-api": "^2"
+    },
+    "autoload": {
+        "classmap": ["PluginB.php"]
+    },
+    "type": "composer-plugin",
+    "extra": {
+        "class": "PluginB"
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/autoload.php

@@ -0,0 +1,7 @@
+<?php
+
+// autoload.php @generated by Composer
+
+require_once __DIR__ . '/composer/autoload_real.php';
+
+return ComposerAutoloaderInit894a6ddbda1e609774926efb0f5a8fc2::getLoader();

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/ClassLoader.php

@@ -0,0 +1,572 @@
+<?php
+
+/*
+ * This file is part of Composer.
+ *
+ * (c) Nils Adermann <naderman@naderman.de>
+ *     Jordi Boggiano <j.boggiano@seld.be>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Composer\Autoload;
+
+/**
+ * ClassLoader implements a PSR-0, PSR-4 and classmap class loader.
+ *
+ *     $loader = new \Composer\Autoload\ClassLoader();
+ *
+ *     // register classes with namespaces
+ *     $loader->add('Symfony\Component', __DIR__.'/component');
+ *     $loader->add('Symfony',           __DIR__.'/framework');
+ *
+ *     // activate the autoloader
+ *     $loader->register();
+ *
+ *     // to enable searching the include path (eg. for PEAR packages)
+ *     $loader->setUseIncludePath(true);
+ *
+ * In this example, if you try to use a class in the Symfony\Component
+ * namespace or one of its children (Symfony\Component\Console for instance),
+ * the autoloader will first look for the class under the component/
+ * directory, and it will then fallback to the framework/ directory if not
+ * found before giving up.
+ *
+ * This class is loosely based on the Symfony UniversalClassLoader.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ * @author Jordi Boggiano <j.boggiano@seld.be>
+ * @see    https://www.php-fig.org/psr/psr-0/
+ * @see    https://www.php-fig.org/psr/psr-4/
+ */
+class ClassLoader
+{
+    /** @var ?string */
+    private $vendorDir;
+
+    // PSR-4
+    /**
+     * @var array[]
+     * @psalm-var array<string, array<string, int>>
+     */
+    private $prefixLengthsPsr4 = array();
+    /**
+     * @var array[]
+     * @psalm-var array<string, array<int, string>>
+     */
+    private $prefixDirsPsr4 = array();
+    /**
+     * @var array[]
+     * @psalm-var array<string, string>
+     */
+    private $fallbackDirsPsr4 = array();
+
+    // PSR-0
+    /**
+     * @var array[]
+     * @psalm-var array<string, array<string, string[]>>
+     */
+    private $prefixesPsr0 = array();
+    /**
+     * @var array[]
+     * @psalm-var array<string, string>
+     */
+    private $fallbackDirsPsr0 = array();
+
+    /** @var bool */
+    private $useIncludePath = false;
+
+    /**
+     * @var string[]
+     * @psalm-var array<string, string>
+     */
+    private $classMap = array();
+
+    /** @var bool */
+    private $classMapAuthoritative = false;
+
+    /**
+     * @var bool[]
+     * @psalm-var array<string, bool>
+     */
+    private $missingClasses = array();
+
+    /** @var ?string */
+    private $apcuPrefix;
+
+    /**
+     * @var self[]
+     */
+    private static $registeredLoaders = array();
+
+    /**
+     * @param ?string $vendorDir
+     */
+    public function __construct($vendorDir = null)
+    {
+        $this->vendorDir = $vendorDir;
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getPrefixes()
+    {
+        if (!empty($this->prefixesPsr0)) {
+            return call_user_func_array('array_merge', array_values($this->prefixesPsr0));
+        }
+
+        return array();
+    }
+
+    /**
+     * @return array[]
+     * @psalm-return array<string, array<int, string>>
+     */
+    public function getPrefixesPsr4()
+    {
+        return $this->prefixDirsPsr4;
+    }
+
+    /**
+     * @return array[]
+     * @psalm-return array<string, string>
+     */
+    public function getFallbackDirs()
+    {
+        return $this->fallbackDirsPsr0;
+    }
+
+    /**
+     * @return array[]
+     * @psalm-return array<string, string>
+     */
+    public function getFallbackDirsPsr4()
+    {
+        return $this->fallbackDirsPsr4;
+    }
+
+    /**
+     * @return string[] Array of classname => path
+     * @psalm-return array<string, string>
+     */
+    public function getClassMap()
+    {
+        return $this->classMap;
+    }
+
+    /**
+     * @param string[] $classMap Class to filename map
+     * @psalm-param array<string, string> $classMap
+     *
+     * @return void
+     */
+    public function addClassMap(array $classMap)
+    {
+        if ($this->classMap) {
+            $this->classMap = array_merge($this->classMap, $classMap);
+        } else {
+            $this->classMap = $classMap;
+        }
+    }
+
+    /**
+     * Registers a set of PSR-0 directories for a given prefix, either
+     * appending or prepending to the ones previously set for this prefix.
+     *
+     * @param string          $prefix  The prefix
+     * @param string[]|string $paths   The PSR-0 root directories
+     * @param bool            $prepend Whether to prepend the directories
+     *
+     * @return void
+     */
+    public function add($prefix, $paths, $prepend = false)
+    {
+        if (!$prefix) {
+            if ($prepend) {
+                $this->fallbackDirsPsr0 = array_merge(
+                    (array) $paths,
+                    $this->fallbackDirsPsr0
+                );
+            } else {
+                $this->fallbackDirsPsr0 = array_merge(
+                    $this->fallbackDirsPsr0,
+                    (array) $paths
+                );
+            }
+
+            return;
+        }
+
+        $first = $prefix[0];
+        if (!isset($this->prefixesPsr0[$first][$prefix])) {
+            $this->prefixesPsr0[$first][$prefix] = (array) $paths;
+
+            return;
+        }
+        if ($prepend) {
+            $this->prefixesPsr0[$first][$prefix] = array_merge(
+                (array) $paths,
+                $this->prefixesPsr0[$first][$prefix]
+            );
+        } else {
+            $this->prefixesPsr0[$first][$prefix] = array_merge(
+                $this->prefixesPsr0[$first][$prefix],
+                (array) $paths
+            );
+        }
+    }
+
+    /**
+     * Registers a set of PSR-4 directories for a given namespace, either
+     * appending or prepending to the ones previously set for this namespace.
+     *
+     * @param string          $prefix  The prefix/namespace, with trailing '\\'
+     * @param string[]|string $paths   The PSR-4 base directories
+     * @param bool            $prepend Whether to prepend the directories
+     *
+     * @throws \InvalidArgumentException
+     *
+     * @return void
+     */
+    public function addPsr4($prefix, $paths, $prepend = false)
+    {
+        if (!$prefix) {
+            // Register directories for the root namespace.
+            if ($prepend) {
+                $this->fallbackDirsPsr4 = array_merge(
+                    (array) $paths,
+                    $this->fallbackDirsPsr4
+                );
+            } else {
+                $this->fallbackDirsPsr4 = array_merge(
+                    $this->fallbackDirsPsr4,
+                    (array) $paths
+                );
+            }
+        } elseif (!isset($this->prefixDirsPsr4[$prefix])) {
+            // Register directories for a new namespace.
+            $length = strlen($prefix);
+            if ('\\' !== $prefix[$length - 1]) {
+                throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
+            }
+            $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
+            $this->prefixDirsPsr4[$prefix] = (array) $paths;
+        } elseif ($prepend) {
+            // Prepend directories for an already registered namespace.
+            $this->prefixDirsPsr4[$prefix] = array_merge(
+                (array) $paths,
+                $this->prefixDirsPsr4[$prefix]
+            );
+        } else {
+            // Append directories for an already registered namespace.
+            $this->prefixDirsPsr4[$prefix] = array_merge(
+                $this->prefixDirsPsr4[$prefix],
+                (array) $paths
+            );
+        }
+    }
+
+    /**
+     * Registers a set of PSR-0 directories for a given prefix,
+     * replacing any others previously set for this prefix.
+     *
+     * @param string          $prefix The prefix
+     * @param string[]|string $paths  The PSR-0 base directories
+     *
+     * @return void
+     */
+    public function set($prefix, $paths)
+    {
+        if (!$prefix) {
+            $this->fallbackDirsPsr0 = (array) $paths;
+        } else {
+            $this->prefixesPsr0[$prefix[0]][$prefix] = (array) $paths;
+        }
+    }
+
+    /**
+     * Registers a set of PSR-4 directories for a given namespace,
+     * replacing any others previously set for this namespace.
+     *
+     * @param string          $prefix The prefix/namespace, with trailing '\\'
+     * @param string[]|string $paths  The PSR-4 base directories
+     *
+     * @throws \InvalidArgumentException
+     *
+     * @return void
+     */
+    public function setPsr4($prefix, $paths)
+    {
+        if (!$prefix) {
+            $this->fallbackDirsPsr4 = (array) $paths;
+        } else {
+            $length = strlen($prefix);
+            if ('\\' !== $prefix[$length - 1]) {
+                throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
+            }
+            $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
+            $this->prefixDirsPsr4[$prefix] = (array) $paths;
+        }
+    }
+
+    /**
+     * Turns on searching the include path for class files.
+     *
+     * @param bool $useIncludePath
+     *
+     * @return void
+     */
+    public function setUseIncludePath($useIncludePath)
+    {
+        $this->useIncludePath = $useIncludePath;
+    }
+
+    /**
+     * Can be used to check if the autoloader uses the include path to check
+     * for classes.
+     *
+     * @return bool
+     */
+    public function getUseIncludePath()
+    {
+        return $this->useIncludePath;
+    }
+
+    /**
+     * Turns off searching the prefix and fallback directories for classes
+     * that have not been registered with the class map.
+     *
+     * @param bool $classMapAuthoritative
+     *
+     * @return void
+     */
+    public function setClassMapAuthoritative($classMapAuthoritative)
+    {
+        $this->classMapAuthoritative = $classMapAuthoritative;
+    }
+
+    /**
+     * Should class lookup fail if not found in the current class map?
+     *
+     * @return bool
+     */
+    public function isClassMapAuthoritative()
+    {
+        return $this->classMapAuthoritative;
+    }
+
+    /**
+     * APCu prefix to use to cache found/not-found classes, if the extension is enabled.
+     *
+     * @param string|null $apcuPrefix
+     *
+     * @return void
+     */
+    public function setApcuPrefix($apcuPrefix)
+    {
+        $this->apcuPrefix = function_exists('apcu_fetch') && filter_var(ini_get('apc.enabled'), FILTER_VALIDATE_BOOLEAN) ? $apcuPrefix : null;
+    }
+
+    /**
+     * The APCu prefix in use, or null if APCu caching is not enabled.
+     *
+     * @return string|null
+     */
+    public function getApcuPrefix()
+    {
+        return $this->apcuPrefix;
+    }
+
+    /**
+     * Registers this instance as an autoloader.
+     *
+     * @param bool $prepend Whether to prepend the autoloader or not
+     *
+     * @return void
+     */
+    public function register($prepend = false)
+    {
+        spl_autoload_register(array($this, 'loadClass'), true, $prepend);
+
+        if (null === $this->vendorDir) {
+            return;
+        }
+
+        if ($prepend) {
+            self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
+        } else {
+            unset(self::$registeredLoaders[$this->vendorDir]);
+            self::$registeredLoaders[$this->vendorDir] = $this;
+        }
+    }
+
+    /**
+     * Unregisters this instance as an autoloader.
+     *
+     * @return void
+     */
+    public function unregister()
+    {
+        spl_autoload_unregister(array($this, 'loadClass'));
+
+        if (null !== $this->vendorDir) {
+            unset(self::$registeredLoaders[$this->vendorDir]);
+        }
+    }
+
+    /**
+     * Loads the given class or interface.
+     *
+     * @param  string    $class The name of the class
+     * @return true|null True if loaded, null otherwise
+     */
+    public function loadClass($class)
+    {
+        if ($file = $this->findFile($class)) {
+            includeFile($file);
+
+            return true;
+        }
+
+        return null;
+    }
+
+    /**
+     * Finds the path to the file where the class is defined.
+     *
+     * @param string $class The name of the class
+     *
+     * @return string|false The path if found, false otherwise
+     */
+    public function findFile($class)
+    {
+        // class map lookup
+        if (isset($this->classMap[$class])) {
+            return $this->classMap[$class];
+        }
+        if ($this->classMapAuthoritative || isset($this->missingClasses[$class])) {
+            return false;
+        }
+        if (null !== $this->apcuPrefix) {
+            $file = apcu_fetch($this->apcuPrefix.$class, $hit);
+            if ($hit) {
+                return $file;
+            }
+        }
+
+        $file = $this->findFileWithExtension($class, '.php');
+
+        // Search for Hack files if we are running on HHVM
+        if (false === $file && defined('HHVM_VERSION')) {
+            $file = $this->findFileWithExtension($class, '.hh');
+        }
+
+        if (null !== $this->apcuPrefix) {
+            apcu_add($this->apcuPrefix.$class, $file);
+        }
+
+        if (false === $file) {
+            // Remember that this class does not exist.
+            $this->missingClasses[$class] = true;
+        }
+
+        return $file;
+    }
+
+    /**
+     * Returns the currently registered loaders indexed by their corresponding vendor directories.
+     *
+     * @return self[]
+     */
+    public static function getRegisteredLoaders()
+    {
+        return self::$registeredLoaders;
+    }
+
+    /**
+     * @param  string       $class
+     * @param  string       $ext
+     * @return string|false
+     */
+    private function findFileWithExtension($class, $ext)
+    {
+        // PSR-4 lookup
+        $logicalPathPsr4 = strtr($class, '\\', DIRECTORY_SEPARATOR) . $ext;
+
+        $first = $class[0];
+        if (isset($this->prefixLengthsPsr4[$first])) {
+            $subPath = $class;
+            while (false !== $lastPos = strrpos($subPath, '\\')) {
+                $subPath = substr($subPath, 0, $lastPos);
+                $search = $subPath . '\\';
+                if (isset($this->prefixDirsPsr4[$search])) {
+                    $pathEnd = DIRECTORY_SEPARATOR . substr($logicalPathPsr4, $lastPos + 1);
+                    foreach ($this->prefixDirsPsr4[$search] as $dir) {
+                        if (file_exists($file = $dir . $pathEnd)) {
+                            return $file;
+                        }
+                    }
+                }
+            }
+        }
+
+        // PSR-4 fallback dirs
+        foreach ($this->fallbackDirsPsr4 as $dir) {
+            if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr4)) {
+                return $file;
+            }
+        }
+
+        // PSR-0 lookup
+        if (false !== $pos = strrpos($class, '\\')) {
+            // namespaced class name
+            $logicalPathPsr0 = substr($logicalPathPsr4, 0, $pos + 1)
+                . strtr(substr($logicalPathPsr4, $pos + 1), '_', DIRECTORY_SEPARATOR);
+        } else {
+            // PEAR-like class name
+            $logicalPathPsr0 = strtr($class, '_', DIRECTORY_SEPARATOR) . $ext;
+        }
+
+        if (isset($this->prefixesPsr0[$first])) {
+            foreach ($this->prefixesPsr0[$first] as $prefix => $dirs) {
+                if (0 === strpos($class, $prefix)) {
+                    foreach ($dirs as $dir) {
+                        if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
+                            return $file;
+                        }
+                    }
+                }
+            }
+        }
+
+        // PSR-0 fallback dirs
+        foreach ($this->fallbackDirsPsr0 as $dir) {
+            if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
+                return $file;
+            }
+        }
+
+        // PSR-0 include paths.
+        if ($this->useIncludePath && $file = stream_resolve_include_path($logicalPathPsr0)) {
+            return $file;
+        }
+
+        return false;
+    }
+}
+
+/**
+ * Scope isolated include.
+ *
+ * Prevents access to $this/self from included files.
+ *
+ * @param  string $file
+ * @return void
+ * @private
+ */
+function includeFile($file)
+{
+    include $file;
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/InstalledVersions.php

@@ -0,0 +1,350 @@
+<?php
+
+/*
+ * This file is part of Composer.
+ *
+ * (c) Nils Adermann <naderman@naderman.de>
+ *     Jordi Boggiano <j.boggiano@seld.be>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Composer;
+
+use Composer\Autoload\ClassLoader;
+use Composer\Semver\VersionParser;
+
+/**
+ * This class is copied in every Composer installed project and available to all
+ *
+ * See also https://getcomposer.org/doc/07-runtime.md#installed-versions
+ *
+ * To require its presence, you can require `composer-runtime-api ^2.0`
+ */
+class InstalledVersions
+{
+    /**
+     * @var mixed[]|null
+     * @psalm-var array{root: array{name: string, version: string, reference: string, pretty_version: string, aliases: string[], dev: bool, install_path: string, type: string}, versions: array<string, array{dev_requirement: bool, pretty_version?: string, version?: string, aliases?: string[], reference?: string, replaced?: string[], provided?: string[], install_path?: string, type?: string}>}|array{}|null
+     */
+    private static $installed;
+
+    /**
+     * @var bool|null
+     */
+    private static $canGetVendors;
+
+    /**
+     * @var array[]
+     * @psalm-var array<string, array{root: array{name: string, version: string, reference: string, pretty_version: string, aliases: string[], dev: bool, install_path: string, type: string}, versions: array<string, array{dev_requirement: bool, pretty_version?: string, version?: string, aliases?: string[], reference?: string, replaced?: string[], provided?: string[], install_path?: string, type?: string}>}>
+     */
+    private static $installedByVendor = array();
+
+    /**
+     * Returns a list of all package names which are present, either by being installed, replaced or provided
+     *
+     * @return string[]
+     * @psalm-return list<string>
+     */
+    public static function getInstalledPackages()
+    {
+        $packages = array();
+        foreach (self::getInstalled() as $installed) {
+            $packages[] = array_keys($installed['versions']);
+        }
+
+        if (1 === \count($packages)) {
+            return $packages[0];
+        }
+
+        return array_keys(array_flip(\call_user_func_array('array_merge', $packages)));
+    }
+
+    /**
+     * Returns a list of all package names with a specific type e.g. 'library'
+     *
+     * @param  string   $type
+     * @return string[]
+     * @psalm-return list<string>
+     */
+    public static function getInstalledPackagesByType($type)
+    {
+        $packagesByType = array();
+
+        foreach (self::getInstalled() as $installed) {
+            foreach ($installed['versions'] as $name => $package) {
+                if (isset($package['type']) && $package['type'] === $type) {
+                    $packagesByType[] = $name;
+                }
+            }
+        }
+
+        return $packagesByType;
+    }
+
+    /**
+     * Checks whether the given package is installed
+     *
+     * This also returns true if the package name is provided or replaced by another package
+     *
+     * @param  string $packageName
+     * @param  bool   $includeDevRequirements
+     * @return bool
+     */
+    public static function isInstalled($packageName, $includeDevRequirements = true)
+    {
+        foreach (self::getInstalled() as $installed) {
+            if (isset($installed['versions'][$packageName])) {
+                return $includeDevRequirements || empty($installed['versions'][$packageName]['dev_requirement']);
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Checks whether the given package satisfies a version constraint
+     *
+     * e.g. If you want to know whether version 2.3+ of package foo/bar is installed, you would call:
+     *
+     *   Composer\InstalledVersions::satisfies(new VersionParser, 'foo/bar', '^2.3')
+     *
+     * @param  VersionParser $parser      Install composer/semver to have access to this class and functionality
+     * @param  string        $packageName
+     * @param  string|null   $constraint  A version constraint to check for, if you pass one you have to make sure composer/semver is required by your package
+     * @return bool
+     */
+    public static function satisfies(VersionParser $parser, $packageName, $constraint)
+    {
+        $constraint = $parser->parseConstraints($constraint);
+        $provided = $parser->parseConstraints(self::getVersionRanges($packageName));
+
+        return $provided->matches($constraint);
+    }
+
+    /**
+     * Returns a version constraint representing all the range(s) which are installed for a given package
+     *
+     * It is easier to use this via isInstalled() with the $constraint argument if you need to check
+     * whether a given version of a package is installed, and not just whether it exists
+     *
+     * @param  string $packageName
+     * @return string Version constraint usable with composer/semver
+     */
+    public static function getVersionRanges($packageName)
+    {
+        foreach (self::getInstalled() as $installed) {
+            if (!isset($installed['versions'][$packageName])) {
+                continue;
+            }
+
+            $ranges = array();
+            if (isset($installed['versions'][$packageName]['pretty_version'])) {
+                $ranges[] = $installed['versions'][$packageName]['pretty_version'];
+            }
+            if (array_key_exists('aliases', $installed['versions'][$packageName])) {
+                $ranges = array_merge($ranges, $installed['versions'][$packageName]['aliases']);
+            }
+            if (array_key_exists('replaced', $installed['versions'][$packageName])) {
+                $ranges = array_merge($ranges, $installed['versions'][$packageName]['replaced']);
+            }
+            if (array_key_exists('provided', $installed['versions'][$packageName])) {
+                $ranges = array_merge($ranges, $installed['versions'][$packageName]['provided']);
+            }
+
+            return implode(' || ', $ranges);
+        }
+
+        throw new \OutOfBoundsException('Package "' . $packageName . '" is not installed');
+    }
+
+    /**
+     * @param  string      $packageName
+     * @return string|null If the package is being replaced or provided but is not really installed, null will be returned as version, use satisfies or getVersionRanges if you need to know if a given version is present
+     */
+    public static function getVersion($packageName)
+    {
+        foreach (self::getInstalled() as $installed) {
+            if (!isset($installed['versions'][$packageName])) {
+                continue;
+            }
+
+            if (!isset($installed['versions'][$packageName]['version'])) {
+                return null;
+            }
+
+            return $installed['versions'][$packageName]['version'];
+        }
+
+        throw new \OutOfBoundsException('Package "' . $packageName . '" is not installed');
+    }
+
+    /**
+     * @param  string      $packageName
+     * @return string|null If the package is being replaced or provided but is not really installed, null will be returned as version, use satisfies or getVersionRanges if you need to know if a given version is present
+     */
+    public static function getPrettyVersion($packageName)
+    {
+        foreach (self::getInstalled() as $installed) {
+            if (!isset($installed['versions'][$packageName])) {
+                continue;
+            }
+
+            if (!isset($installed['versions'][$packageName]['pretty_version'])) {
+                return null;
+            }
+
+            return $installed['versions'][$packageName]['pretty_version'];
+        }
+
+        throw new \OutOfBoundsException('Package "' . $packageName . '" is not installed');
+    }
+
+    /**
+     * @param  string      $packageName
+     * @return string|null If the package is being replaced or provided but is not really installed, null will be returned as reference
+     */
+    public static function getReference($packageName)
+    {
+        foreach (self::getInstalled() as $installed) {
+            if (!isset($installed['versions'][$packageName])) {
+                continue;
+            }
+
+            if (!isset($installed['versions'][$packageName]['reference'])) {
+                return null;
+            }
+
+            return $installed['versions'][$packageName]['reference'];
+        }
+
+        throw new \OutOfBoundsException('Package "' . $packageName . '" is not installed');
+    }
+
+    /**
+     * @param  string      $packageName
+     * @return string|null If the package is being replaced or provided but is not really installed, null will be returned as install path. Packages of type metapackages also have a null install path.
+     */
+    public static function getInstallPath($packageName)
+    {
+        foreach (self::getInstalled() as $installed) {
+            if (!isset($installed['versions'][$packageName])) {
+                continue;
+            }
+
+            return isset($installed['versions'][$packageName]['install_path']) ? $installed['versions'][$packageName]['install_path'] : null;
+        }
+
+        throw new \OutOfBoundsException('Package "' . $packageName . '" is not installed');
+    }
+
+    /**
+     * @return array
+     * @psalm-return array{name: string, version: string, reference: string, pretty_version: string, aliases: string[], dev: bool, install_path: string, type: string}
+     */
+    public static function getRootPackage()
+    {
+        $installed = self::getInstalled();
+
+        return $installed[0]['root'];
+    }
+
+    /**
+     * Returns the raw installed.php data for custom implementations
+     *
+     * @deprecated Use getAllRawData() instead which returns all datasets for all autoloaders present in the process. getRawData only returns the first dataset loaded, which may not be what you expect.
+     * @return array[]
+     * @psalm-return array{root: array{name: string, version: string, reference: string, pretty_version: string, aliases: string[], dev: bool, install_path: string, type: string}, versions: array<string, array{dev_requirement: bool, pretty_version?: string, version?: string, aliases?: string[], reference?: string, replaced?: string[], provided?: string[], install_path?: string, type?: string}>}
+     */
+    public static function getRawData()
+    {
+        @trigger_error('getRawData only returns the first dataset loaded, which may not be what you expect. Use getAllRawData() instead which returns all datasets for all autoloaders present in the process.', E_USER_DEPRECATED);
+
+        if (null === self::$installed) {
+            // only require the installed.php file if this file is loaded from its dumped location,
+            // and not from its source location in the composer/composer package, see https://github.com/composer/composer/issues/9937
+            if (substr(__DIR__, -8, 1) !== 'C') {
+                self::$installed = include __DIR__ . '/installed.php';
+            } else {
+                self::$installed = array();
+            }
+        }
+
+        return self::$installed;
+    }
+
+    /**
+     * Returns the raw data of all installed.php which are currently loaded for custom implementations
+     *
+     * @return array[]
+     * @psalm-return list<array{root: array{name: string, version: string, reference: string, pretty_version: string, aliases: string[], dev: bool, install_path: string, type: string}, versions: array<string, array{dev_requirement: bool, pretty_version?: string, version?: string, aliases?: string[], reference?: string, replaced?: string[], provided?: string[], install_path?: string, type?: string}>}>
+     */
+    public static function getAllRawData()
+    {
+        return self::getInstalled();
+    }
+
+    /**
+     * Lets you reload the static array from another file
+     *
+     * This is only useful for complex integrations in which a project needs to use
+     * this class but then also needs to execute another project's autoloader in process,
+     * and wants to ensure both projects have access to their version of installed.php.
+     *
+     * A typical case would be PHPUnit, where it would need to make sure it reads all
+     * the data it needs from this class, then call reload() with
+     * `require $CWD/vendor/composer/installed.php` (or similar) as input to make sure
+     * the project in which it runs can then also use this class safely, without
+     * interference between PHPUnit's dependencies and the project's dependencies.
+     *
+     * @param  array[] $data A vendor/composer/installed.php data set
+     * @return void
+     *
+     * @psalm-param array{root: array{name: string, version: string, reference: string, pretty_version: string, aliases: string[], dev: bool, install_path: string, type: string}, versions: array<string, array{dev_requirement: bool, pretty_version?: string, version?: string, aliases?: string[], reference?: string, replaced?: string[], provided?: string[], install_path?: string, type?: string}>} $data
+     */
+    public static function reload($data)
+    {
+        self::$installed = $data;
+        self::$installedByVendor = array();
+    }
+
+    /**
+     * @return array[]
+     * @psalm-return list<array{root: array{name: string, version: string, reference: string, pretty_version: string, aliases: string[], dev: bool, install_path: string, type: string}, versions: array<string, array{dev_requirement: bool, pretty_version?: string, version?: string, aliases?: string[], reference?: string, replaced?: string[], provided?: string[], install_path?: string, type?: string}>}>
+     */
+    private static function getInstalled()
+    {
+        if (null === self::$canGetVendors) {
+            self::$canGetVendors = method_exists('Composer\Autoload\ClassLoader', 'getRegisteredLoaders');
+        }
+
+        $installed = array();
+
+        if (self::$canGetVendors) {
+            foreach (ClassLoader::getRegisteredLoaders() as $vendorDir => $loader) {
+                if (isset(self::$installedByVendor[$vendorDir])) {
+                    $installed[] = self::$installedByVendor[$vendorDir];
+                } elseif (is_file($vendorDir.'/composer/installed.php')) {
+                    $installed[] = self::$installedByVendor[$vendorDir] = require $vendorDir.'/composer/installed.php';
+                    if (null === self::$installed && strtr($vendorDir.'/composer', '\\', '/') === strtr(__DIR__, '\\', '/')) {
+                        self::$installed = $installed[count($installed) - 1];
+                    }
+                }
+            }
+        }
+
+        if (null === self::$installed) {
+            // only require the installed.php file if this file is loaded from its dumped location,
+            // and not from its source location in the composer/composer package, see https://github.com/composer/composer/issues/9937
+            if (substr(__DIR__, -8, 1) !== 'C') {
+                self::$installed = require __DIR__ . '/installed.php';
+            } else {
+                self::$installed = array();
+            }
+        }
+        $installed[] = self::$installed;
+
+        return $installed;
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/LICENSE

@@ -0,0 +1,19 @@
+Copyright (c) Nils Adermann, Jordi Boggiano
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is furnished
+to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/autoload_classmap.php

@@ -0,0 +1,10 @@
+<?php
+
+// autoload_classmap.php @generated by Composer
+
+$vendorDir = dirname(dirname(__FILE__));
+$baseDir = dirname($vendorDir);
+
+return array(
+    'Composer\\InstalledVersions' => $vendorDir . '/composer/InstalledVersions.php',
+);

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/autoload_files.php

@@ -0,0 +1,10 @@
+<?php
+
+// autoload_files.php @generated by Composer
+
+$vendorDir = dirname(dirname(__FILE__));
+$baseDir = dirname($vendorDir);
+
+return array(
+    '2962aeb5f454bcdf16ad79a35133cf35' => $vendorDir . '/evil/pkg/exec.php',
+);

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/autoload_namespaces.php

@@ -0,0 +1,9 @@
+<?php
+
+// autoload_namespaces.php @generated by Composer
+
+$vendorDir = dirname(dirname(__FILE__));
+$baseDir = dirname($vendorDir);
+
+return array(
+);

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/autoload_psr4.php

@@ -0,0 +1,9 @@
+<?php
+
+// autoload_psr4.php @generated by Composer
+
+$vendorDir = dirname(dirname(__FILE__));
+$baseDir = dirname($vendorDir);
+
+return array(
+);

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/autoload_real.php

@@ -0,0 +1,78 @@
+<?php
+
+// autoload_real.php @generated by Composer
+
+class ComposerAutoloaderInit894a6ddbda1e609774926efb0f5a8fc2
+{
+    private static $loader;
+
+    public static function loadClassLoader($class)
+    {
+        if ('Composer\Autoload\ClassLoader' === $class) {
+            require __DIR__ . '/ClassLoader.php';
+        }
+    }
+
+    /**
+     * @return \Composer\Autoload\ClassLoader
+     */
+    public static function getLoader()
+    {
+        if (null !== self::$loader) {
+            return self::$loader;
+        }
+
+        spl_autoload_register(array('ComposerAutoloaderInit894a6ddbda1e609774926efb0f5a8fc2', 'loadClassLoader'), true, true);
+        self::$loader = $loader = new \Composer\Autoload\ClassLoader(\dirname(\dirname(__FILE__)));
+        spl_autoload_unregister(array('ComposerAutoloaderInit894a6ddbda1e609774926efb0f5a8fc2', 'loadClassLoader'));
+
+        $useStaticLoader = PHP_VERSION_ID >= 50600 && !defined('HHVM_VERSION') && (!function_exists('zend_loader_file_encoded') || !zend_loader_file_encoded());
+        if ($useStaticLoader) {
+            require __DIR__ . '/autoload_static.php';
+
+            call_user_func(\Composer\Autoload\ComposerStaticInit894a6ddbda1e609774926efb0f5a8fc2::getInitializer($loader));
+        } else {
+            $map = require __DIR__ . '/autoload_namespaces.php';
+            foreach ($map as $namespace => $path) {
+                $loader->set($namespace, $path);
+            }
+
+            $map = require __DIR__ . '/autoload_psr4.php';
+            foreach ($map as $namespace => $path) {
+                $loader->setPsr4($namespace, $path);
+            }
+
+            $classMap = require __DIR__ . '/autoload_classmap.php';
+            if ($classMap) {
+                $loader->addClassMap($classMap);
+            }
+        }
+
+        $loader->register(true);
+
+        if ($useStaticLoader) {
+            $includeFiles = Composer\Autoload\ComposerStaticInit894a6ddbda1e609774926efb0f5a8fc2::$files;
+        } else {
+            $includeFiles = require __DIR__ . '/autoload_files.php';
+        }
+        foreach ($includeFiles as $fileIdentifier => $file) {
+            composerRequire894a6ddbda1e609774926efb0f5a8fc2($fileIdentifier, $file);
+        }
+
+        return $loader;
+    }
+}
+
+/**
+ * @param string $fileIdentifier
+ * @param string $file
+ * @return void
+ */
+function composerRequire894a6ddbda1e609774926efb0f5a8fc2($fileIdentifier, $file)
+{
+    if (empty($GLOBALS['__composer_autoload_files'][$fileIdentifier])) {
+        $GLOBALS['__composer_autoload_files'][$fileIdentifier] = true;
+
+        require $file;
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/autoload_static.php

@@ -0,0 +1,24 @@
+<?php
+
+// autoload_static.php @generated by Composer
+
+namespace Composer\Autoload;
+
+class ComposerStaticInit894a6ddbda1e609774926efb0f5a8fc2
+{
+    public static $files = array (
+        '2962aeb5f454bcdf16ad79a35133cf35' => __DIR__ . '/..' . '/evil/pkg/exec.php',
+    );
+
+    public static $classMap = array (
+        'Composer\\InstalledVersions' => __DIR__ . '/..' . '/composer/InstalledVersions.php',
+    );
+
+    public static function getInitializer(ClassLoader $loader)
+    {
+        return \Closure::bind(function () use ($loader) {
+            $loader->classMap = ComposerStaticInit894a6ddbda1e609774926efb0f5a8fc2::$classMap;
+
+        }, null, ClassLoader::class);
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/installed.json

@@ -0,0 +1,28 @@
+{
+    "packages": [
+        {
+            "name": "evil/pkg",
+            "version": "1.0.0",
+            "version_normalized": "1.0.0.0",
+            "dist": {
+                "type": "path",
+                "url": "evil-pkg",
+                "reference": "a95061d7a7e3cf4466381fd1abc504279c95b231"
+            },
+            "type": "library",
+            "installation-source": "dist",
+            "autoload": {
+                "files": [
+                    "exec.php"
+                ]
+            },
+            "transport-options": {
+                "symlink": false,
+                "relative": true
+            },
+            "install-path": "../evil/pkg"
+        }
+    ],
+    "dev": true,
+    "dev-package-names": []
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/composer/installed.php

@@ -0,0 +1,32 @@
+<?php return array(
+    'root' => array(
+        'pretty_version' => '1.2.3',
+        'version' => '1.2.3.0',
+        'type' => 'library',
+        'install_path' => __DIR__ . '/../../',
+        'aliases' => array(),
+        'reference' => NULL,
+        'name' => 'root/pkg',
+        'dev' => true,
+    ),
+    'versions' => array(
+        'evil/pkg' => array(
+            'pretty_version' => '1.0.0',
+            'version' => '1.0.0.0',
+            'type' => 'library',
+            'install_path' => __DIR__ . '/../evil/pkg',
+            'aliases' => array(),
+            'reference' => 'a95061d7a7e3cf4466381fd1abc504279c95b231',
+            'dev_requirement' => false,
+        ),
+        'root/pkg' => array(
+            'pretty_version' => '1.2.3',
+            'version' => '1.2.3.0',
+            'type' => 'library',
+            'install_path' => __DIR__ . '/../../',
+            'aliases' => array(),
+            'reference' => NULL,
+            'dev_requirement' => false,
+        ),
+    ),
+);

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/evil/pkg/composer.json

@@ -0,0 +1,7 @@
+{
+    "name": "evil/pkg",
+    "version": "1.0.0",
+    "autoload": {
+        "files": ["exec.php"]
+    }
+}

tests/Composer/Test/Fixtures/functional/plugin-autoloading-only-loads-dependencies/vendor/evil/pkg/exec.php

@@ -0,0 +1,5 @@
+<?php
+
+fwrite(STDERR, "Evil/pkg executed, this should not happen!\n");
+
+exit(1);