Bump phpstan to level 3 (#9734)

Clean up PackageInterface/CompletePackageInterface, add missing methods, type things in solver as BasePackage, added CompleteAliasPackage, ..

.github/workflows/phpstan.yml

@@ -52,5 +52,5 @@ jobs:
       - name: Run PHPStan
         # Locked to phpunit 7.5 here as newer ones have void return types which break inheritance
         run: |
-          bin/composer require --dev phpstan/phpstan:^0.12.69 phpunit/phpunit:^7.5.20 --with-all-dependencies ${{ env.COMPOSER_FLAGS }}
+          bin/composer require --dev phpstan/phpstan:^0.12.69 phpstan/phpstan-phpunit:^0.12.17 phpunit/phpunit:^7.5.20 --with-all-dependencies ${{ env.COMPOSER_FLAGS }}
           vendor/bin/phpstan analyse --configuration=phpstan/config.neon

phpstan/config.neon

@@ -1,6 +1,8 @@
+includes:
+    - ../vendor/phpstan/phpstan-phpunit/extension.neon
+
 parameters:
-    level: 1
+    level: 3
-    checkClassCaseSensitivity: true # Level 2 rule
     excludes_analyse:
        - '../tests/Composer/Test/Fixtures/*'
        - '../tests/Composer/Test/Autoload/Fixtures/*'
@@ -29,6 +31,9 @@ parameters:
         - '~^Call to an undefined static method Composer\\Test\\PolyfillTestCase::setExpectedException\(\)\.$~'
         - '~^Call to an undefined method Composer\\Test\\[a-zA-Z0-9\\]+::(assertFileDoesNotExist|assertMatchesRegularExpression)\(\)\.$~'
 
+        # Mock errors
+        - '~^Call to an undefined method (PHPUnit\\Framework\\MockObject\\MockObject|Prophecy\\Prophecy\\ObjectProphecy)::.*$~'
+
     bootstrapFiles:
         - ../tests/bootstrap.php
 
@@ -38,25 +43,3 @@ parameters:
 
 rules:
     - Composer\PHPStanRules\AnonymousFunctionWithThisRule
-    # Level 2 rules
-    - PHPStan\Rules\Cast\EchoRule
-    - PHPStan\Rules\Cast\InvalidCastRule
-    - PHPStan\Rules\Cast\InvalidPartOfEncapsedStringRule
-    - PHPStan\Rules\Cast\PrintRule
-    - PHPStan\Rules\Functions\IncompatibleDefaultParameterTypeRule
-    - PHPStan\Rules\Generics\ClassAncestorsRule
-    - PHPStan\Rules\Generics\ClassTemplateTypeRule
-    - PHPStan\Rules\Generics\FunctionTemplateTypeRule
-    - PHPStan\Rules\Generics\FunctionSignatureVarianceRule
-    - PHPStan\Rules\Generics\InterfaceAncestorsRule
-    - PHPStan\Rules\Generics\InterfaceTemplateTypeRule
-    - PHPStan\Rules\Generics\MethodTemplateTypeRule
-    - PHPStan\Rules\Generics\MethodSignatureVarianceRule
-    - PHPStan\Rules\Generics\TraitTemplateTypeRule
-    - PHPStan\Rules\Operators\InvalidBinaryOperationRule
-    - PHPStan\Rules\Operators\InvalidUnaryOperationRule
-    - PHPStan\Rules\Operators\InvalidComparisonOperationRule
-    - PHPStan\Rules\PhpDoc\IncompatiblePhpDocTypeRule
-    - PHPStan\Rules\PhpDoc\IncompatiblePropertyPhpDocTypeRule
-    - PHPStan\Rules\PhpDoc\InvalidPhpDocTagValueRule
-    - PHPStan\Rules\PhpDoc\InvalidPHPStanDocTagRule

src/Composer/Autoload/ClassLoader.php

@@ -338,7 +338,7 @@ class ClassLoader
      * Loads the given class or interface.
      *
      * @param  string    $class The name of the class
-     * @return bool|null True if loaded, null otherwise
+     * @return true|null True if loaded, null otherwise
      */
     public function loadClass($class)
     {
@@ -347,6 +347,8 @@ class ClassLoader
 
             return true;
         }
+
+        return null;
     }
 
     /**

src/Composer/Command/ArchiveCommand.php

@@ -16,6 +16,7 @@ use Composer\Factory;
 use Composer\IO\IOInterface;
 use Composer\Config;
 use Composer\Composer;
+use Composer\Package\CompletePackageInterface;
 use Composer\Repository\CompositeRepository;
 use Composer\Repository\RepositoryFactory;
 use Composer\Script\ScriptEvents;
@@ -140,6 +141,9 @@ EOT
         return 0;
     }
 
+    /**
+     * @return CompletePackageInterface|false
+     */
     protected function selectPackage(IOInterface $io, $packageName, $version = null)
     {
         $io->writeError('<info>Searching for the specified package.</info>');
@@ -171,6 +175,10 @@ EOT
             return false;
         }
 
+        if (!$package instanceof CompletePackageInterface) {
+            throw new \LogicException('Expected a CompletePackageInterface instance but found '.get_class($package));
+        }
+
         return $package;
     }
 }

src/Composer/Command/BaseCommand.php

@@ -212,6 +212,8 @@ abstract class BaseCommand extends Command
         if (method_exists($rendererStyle, 'setVerticalBorderChars')) {
             $rendererStyle->setVerticalBorderChars('');
         } else {
+            // TODO remove in composer 2.2
+            // @phpstan-ignore-next-line
             $rendererStyle->setVerticalBorderChar('');
         }
         $rendererStyle->setCellRowContentFormat('%s  ');

src/Composer/Command/DiagnoseCommand.php

@@ -27,6 +27,7 @@ use Composer\Util\StreamContextFactory;
 use Composer\SelfUpdate\Keys;
 use Composer\SelfUpdate\Versions;
 use Composer\IO\NullIO;
+use Composer\Package\CompletePackageInterface;
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Output\OutputInterface;
 use Symfony\Component\Process\ExecutableFinder;
@@ -159,7 +160,7 @@ EOT
         $platformRepo = new PlatformRepository(array(), $platformOverrides);
         $phpPkg = $platformRepo->findPackage('php', '*');
         $phpVersion = $phpPkg->getPrettyVersion();
-        if (false !== strpos($phpPkg->getDescription(), 'overridden')) {
+        if ($phpPkg instanceof CompletePackageInterface && false !== strpos($phpPkg->getDescription(), 'overridden')) {
             $phpVersion .= ' - ' . $phpPkg->getDescription();
         }
 

src/Composer/Command/GlobalCommand.php

@@ -58,6 +58,10 @@ EOT
 
     public function run(InputInterface $input, OutputInterface $output)
     {
+        if (!method_exists($input, '__toString')) {
+            throw new \LogicException('Expected an Input instance that is stringable, got '.get_class($input));
+        }
+
         // extract real command name
         $tokens = preg_split('{\s+}', $input->__toString());
         $args = array();

src/Composer/Command/InitCommand.php

@@ -15,6 +15,7 @@ namespace Composer\Command;
 use Composer\Factory;
 use Composer\Json\JsonFile;
 use Composer\Package\BasePackage;
+use Composer\Package\CompletePackageInterface;
 use Composer\Package\Package;
 use Composer\Package\PackageInterface;
 use Composer\Package\Version\VersionParser;
@@ -31,6 +32,7 @@ use Symfony\Component\Console\Input\InputOption;
 use Symfony\Component\Console\Output\OutputInterface;
 use Symfony\Component\Process\ExecutableFinder;
 use Symfony\Component\Process\Process;
+use Symfony\Component\Console\Helper\FormatterHelper;
 
 /**
  * @author Justin Rainbow <justin.rainbow@gmail.com>
@@ -172,6 +174,7 @@ EOT
     {
         $git = $this->getGitConfig();
         $io = $this->getIO();
+        /** @var FormatterHelper $formatter */
         $formatter = $this->getHelperSet()->get('formatter');
 
         // initialize repos if configured
@@ -831,7 +834,7 @@ EOT
             if (!$link->getConstraint()->matches(new Constraint('==', $platformPkg->getVersion()))) {
                 $platformPkgVersion = $platformPkg->getPrettyVersion();
                 $platformExtra = $platformPkg->getExtra();
-                if (isset($platformExtra['config.platform'])) {
+                if (isset($platformExtra['config.platform']) && $platformPkg instanceof CompletePackageInterface) {
                     $platformPkgVersion .= ' ('.$platformPkg->getDescription().')';
                 }
                 $details[] = $candidate->getName().' requires '.$link->getTarget().' '.$link->getPrettyConstraint().' which does not match your installed version '.$platformPkgVersion.'.';

src/Composer/Command/LicensesCommand.php

@@ -81,6 +81,8 @@ EOT
                 if (method_exists($tableStyle, 'setVerticalBorderChars')) {
                     $tableStyle->setVerticalBorderChars('');
                 } else {
+                    // TODO remove in composer 2.2
+                    // @phpstan-ignore-next-line
                     $tableStyle->setVerticalBorderChar('');
                 }
                 $tableStyle->setCellRowContentFormat('%s  ');

src/Composer/Command/ShowCommand.php

@@ -266,7 +266,13 @@ EOT
                 if ($input->getOption('latest')) {
                     $latestPackage = $this->findLatestPackage($package, $composer, $platformRepo, $input->getOption('minor-only'));
                 }
-                if ($input->getOption('outdated') && $input->getOption('strict') && $latestPackage && $latestPackage->getFullPrettyVersion() !== $package->getFullPrettyVersion() && !$latestPackage->isAbandoned()) {
+                if (
+                    $input->getOption('outdated')
+                    && $input->getOption('strict')
+                    && $latestPackage
+                    && $latestPackage->getFullPrettyVersion() !== $package->getFullPrettyVersion()
+                    && (!$latestPackage instanceof CompletePackageInterface || !$latestPackage->isAbandoned())
+                ) {
                     $exitCode = 1;
                 }
                 if ($input->getOption('path')) {
@@ -330,6 +336,8 @@ EOT
             $width = $terminal->getWidth();
         } else {
             // For versions of Symfony console before 3.2
+            // TODO remove in composer 2.2
+            // @phpstan-ignore-next-line
             list($width) = $this->getApplication()->getTerminalDimensions();
         }
         if (null === $width) {
@@ -386,6 +394,7 @@ EOT
         $showMinorOnly = $input->getOption('minor-only');
         $ignoredPackages = array_map('strtolower', $input->getOption('ignore'));
         $indent = $showAllTypes ? '  ' : '';
+        /** @var PackageInterface[] $latestPackages */
         $latestPackages = array();
         $exitCode = 0;
         $viewData = array();
@@ -426,7 +435,7 @@ EOT
                         }
 
                         // Determine if Composer is checking outdated dependencies and if current package should trigger non-default exit code
-                        $packageIsUpToDate = $latestPackage && $latestPackage->getFullPrettyVersion() === $package->getFullPrettyVersion() && !$latestPackage->isAbandoned();
+                        $packageIsUpToDate = $latestPackage && $latestPackage->getFullPrettyVersion() === $package->getFullPrettyVersion() && (!$latestPackage instanceof CompletePackageInterface || !$latestPackage->isAbandoned());
                         $packageIsIgnored = \in_array($package->getPrettyName(), $ignoredPackages, true);
                         if ($input->getOption('outdated') && ($packageIsUpToDate || $packageIsIgnored)) {
                             continue;
@@ -454,7 +463,7 @@ EOT
                             $packageViewData['path'] = strtok(realpath($composer->getInstallationManager()->getInstallPath($package)), "\r\n");
                         }
 
-                        if ($latestPackage && $latestPackage->isAbandoned()) {
+                        if ($latestPackage instanceof CompletePackageInterface && $latestPackage->isAbandoned()) {
                             $replacement = is_string($latestPackage->getReplacementPackage())
                                 ? 'Use ' . $latestPackage->getReplacementPackage() . ' instead'
                                 : 'No replacement was suggested';
@@ -670,7 +679,7 @@ EOT
         }
         $io->write('<info>names</info>    : ' . implode(', ', $package->getNames()));
 
-        if ($latestPackage->isAbandoned()) {
+        if ($latestPackage instanceof CompletePackageInterface && $latestPackage->isAbandoned()) {
             $replacement = ($latestPackage->getReplacementPackage() !== null)
                 ? ' The author suggests using the ' . $latestPackage->getReplacementPackage(). ' package instead.'
                 : null;
@@ -836,7 +845,7 @@ EOT
             }
         }
 
-        if ($latestPackage->isAbandoned()) {
+        if ($latestPackage instanceof CompletePackageInterface && $latestPackage->isAbandoned()) {
             $json['replacement'] = $latestPackage->getReplacementPackage();
         }
 
@@ -1045,7 +1054,7 @@ EOT
         $tree = array(
             'name' => $package->getPrettyName(),
             'version' => $package->getPrettyVersion(),
-            'description' => $package->getDescription(),
+            'description' => $package instanceof CompletePackageInterface ? $package->getDescription() : '',
         );
 
         if ($children) {
@@ -1112,7 +1121,7 @@ EOT
      * Display a package tree
      *
      * @param  string              $name
-     * @param  PackageInterface|string $package
+     * @param  Link                $link
      * @param  InstalledRepository $installedRepo
      * @param  RepositoryInterface $remoteRepos
      * @param  array               $packagesInTree
@@ -1120,7 +1129,7 @@ EOT
      */
     protected function addTree(
         $name,
-        $package,
+        Link $link,
         InstalledRepository $installedRepo,
         RepositoryInterface $remoteRepos,
         array $packagesInTree
@@ -1130,7 +1139,7 @@ EOT
             $installedRepo,
             $remoteRepos,
             $name,
-            $package->getPrettyConstraint() === 'self.version' ? $package->getConstraint() : $package->getPrettyConstraint()
+            $link->getPrettyConstraint() === 'self.version' ? $link->getConstraint() : $link->getPrettyConstraint()
         );
         if (is_object($package)) {
             $requires = $package->getRequires();

src/Composer/Console/Application.php

@@ -44,7 +44,7 @@ use Composer\Exception\NoSslException;
 class Application extends BaseApplication
 {
     /**
-     * @var Composer
+     * @var ?Composer
      */
     protected $composer;
 

src/Composer/DependencyResolver/Decisions.php

@@ -164,7 +164,7 @@ class Decisions implements \Iterator, \Countable
 
     public function next()
     {
-        return prev($this->decisionQueue);
+        prev($this->decisionQueue);
     }
 
     public function valid()

src/Composer/DependencyResolver/DefaultPolicy.php

@@ -12,9 +12,9 @@
 
 namespace Composer\DependencyResolver;
 
-use Composer\Package\PackageInterface;
 use Composer\Package\AliasPackage;
 use Composer\Package\BasePackage;
+use Composer\Package\PackageInterface;
 use Composer\Semver\Constraint\Constraint;
 
 /**
@@ -88,7 +88,7 @@ class DefaultPolicy implements PolicyInterface
     /**
      * @protected
      */
-    public function compareByPriority(Pool $pool, PackageInterface $a, PackageInterface $b, $requiredPackage = null, $ignoreReplace = false)
+    public function compareByPriority(Pool $pool, BasePackage $a, BasePackage $b, $requiredPackage = null, $ignoreReplace = false)
     {
         // prefer aliases to the original package
         if ($a->getName() === $b->getName()) {
@@ -139,11 +139,11 @@ class DefaultPolicy implements PolicyInterface
      * Replace constraints are ignored. This method should only be used for
      * prioritisation, not for actual constraint verification.
      *
-     * @param  PackageInterface $source
+     * @param  BasePackage $source
-     * @param  PackageInterface $target
+     * @param  BasePackage $target
      * @return bool
      */
-    protected function replaces(PackageInterface $source, PackageInterface $target)
+    protected function replaces(BasePackage $source, BasePackage $target)
     {
         foreach ($source->getReplaces() as $link) {
             if ($link->getTarget() === $target->getName()

src/Composer/DependencyResolver/GenericRule.php

@@ -12,7 +12,7 @@
 
 namespace Composer\DependencyResolver;
 
-use Composer\Package\PackageInterface;
+use Composer\Package\BasePackage;
 use Composer\Package\Link;
 
 /**
@@ -25,7 +25,7 @@ class GenericRule extends Rule
     /**
      * @param array                          $literals
      * @param int|null                       $reason     A RULE_* constant describing the reason for generating this rule
-     * @param Link|PackageInterface|int|null $reasonData
+     * @param Link|BasePackage|int|null $reasonData
      */
     public function __construct(array $literals, $reason, $reasonData)
     {

src/Composer/DependencyResolver/MultiConflictRule.php

@@ -12,7 +12,7 @@
 
 namespace Composer\DependencyResolver;
 
-use Composer\Package\PackageInterface;
+use Composer\Package\BasePackage;
 use Composer\Package\Link;
 
 /**
@@ -27,7 +27,7 @@ class MultiConflictRule extends Rule
     /**
      * @param array                 $literals
      * @param int                   $reason     A RULE_* constant describing the reason for generating this rule
-     * @param Link|PackageInterface $reasonData
+     * @param Link|BasePackage $reasonData
      */
     public function __construct(array $literals, $reason, $reasonData)
     {

src/Composer/DependencyResolver/Pool.php

@@ -16,7 +16,7 @@ use Composer\Package\Version\VersionParser;
 use Composer\Semver\CompilingMatcher;
 use Composer\Semver\Constraint\ConstraintInterface;
 use Composer\Semver\Constraint\Constraint;
-use Composer\Package\PackageInterface;
+use Composer\Package\BasePackage;
 
 /**
  * A package pool contains all packages for dependency resolution
@@ -26,10 +26,13 @@ use Composer\Package\PackageInterface;
  */
 class Pool implements \Countable
 {
+    /** @var BasePackage[] */
     protected $packages = array();
+    /** @var array<string, BasePackage[]> */
     protected $packageByName = array();
     protected $versionParser;
     protected $providerCache = array();
+    /** @var BasePackage[] */
     protected $unacceptableFixedOrLockedPackages;
 
     public function __construct(array $packages = array(), array $unacceptableFixedOrLockedPackages = array())
@@ -54,6 +57,9 @@ class Pool implements \Countable
         }
     }
 
+    /**
+     * @return BasePackage[]
+     */
     public function getPackages()
     {
         return $this->packages;
@@ -63,7 +69,7 @@ class Pool implements \Countable
      * Retrieves the package object for a given package id.
      *
      * @param  int         $id
-     * @return PackageInterface
+     * @return BasePackage
      */
     public function packageById($id)
     {
@@ -84,7 +90,7 @@ class Pool implements \Countable
      * @param  string              $name       The package name to be searched for
      * @param  ConstraintInterface $constraint A constraint that all returned
      *                                         packages must match or null to return all
-     * @return PackageInterface[]  A set of packages
+     * @return BasePackage[]       A set of packages
      */
     public function whatProvides($name, ConstraintInterface $constraint = null)
     {
@@ -140,12 +146,12 @@ class Pool implements \Countable
      * Checks if the package matches the given constraint directly or through
      * provided or replaced packages
      *
-     * @param  PackageInterface    $candidate
+     * @param  BasePackage         $candidate
      * @param  string              $name       Name of the package to be matched
      * @param  ConstraintInterface $constraint The constraint to verify
      * @return bool
      */
-    public function match($candidate, $name, ConstraintInterface $constraint = null)
+    public function match(BasePackage $candidate, $name, ConstraintInterface $constraint = null)
     {
         $candidateName = $candidate->getName();
         $candidateVersion = $candidate->getVersion();
@@ -185,7 +191,7 @@ class Pool implements \Countable
         return false;
     }
 
-    public function isUnacceptableFixedOrLockedPackage(PackageInterface $package)
+    public function isUnacceptableFixedOrLockedPackage(BasePackage $package)
     {
         return \in_array($package, $this->unacceptableFixedOrLockedPackages, true);
     }

src/Composer/DependencyResolver/PoolBuilder.php

@@ -16,6 +16,8 @@ use Composer\EventDispatcher\EventDispatcher;
 use Composer\IO\IOInterface;
 use Composer\Package\AliasPackage;
 use Composer\Package\BasePackage;
+use Composer\Package\CompleteAliasPackage;
+use Composer\Package\CompletePackageInterface;
 use Composer\Package\PackageInterface;
 use Composer\Package\Version\StabilityFilter;
 use Composer\Plugin\PluginEvents;
@@ -43,10 +45,12 @@ class PoolBuilder
      */
     private $stabilityFlags;
     /**
+     * @var array[]
      * @psalm-var array<string, array<string, array{alias: string, alias_normalized: string}>>
      */
     private $rootAliases;
     /**
+     * @var string[]
      * @psalm-var array<string, string>
      */
     private $rootReferences;
@@ -59,27 +63,32 @@ class PoolBuilder
      */
     private $io;
     /**
-     * @psalm-var array<string, AliasPackage>
+     * @var array[]
+     * @psalm-var array<string, AliasPackage[]>
      */
     private $aliasMap = array();
     /**
+     * @var ConstraintInterface[]
      * @psalm-var array<string, ConstraintInterface>
      */
     private $packagesToLoad = array();
     /**
+     * @var ConstraintInterface[]
      * @psalm-var array<string, ConstraintInterface>
      */
     private $loadedPackages = array();
     /**
+     * @var array[]
      * @psalm-var array<int, array<string, array<string, PackageInterface>>>
      */
     private $loadedPerRepo = array();
     /**
-     * @psalm-var Package[]
+     * @var PackageInterface[]
      */
     private $packages = array();
     /**
-     * @psalm-var list<Package>
+     * @var PackageInterface[]
+     * @psalm-var list<PackageInterface>
      */
     private $unacceptableFixedOrLockedPackages = array();
     private $updateAllowList = array();
@@ -95,6 +104,7 @@ class PoolBuilder
      */
     private $maxExtendedReqs = array();
     /**
+     * @var array
      * @psalm-var array<string, bool>
      */
     private $updateAllowWarned = array();
@@ -360,7 +370,11 @@ class PoolBuilder
             } else {
                 $basePackage = $package;
             }
+            if ($basePackage instanceof CompletePackageInterface) {
+                $aliasPackage = new CompleteAliasPackage($basePackage, $alias['alias_normalized'], $alias['alias']);
+            } else {
                 $aliasPackage = new AliasPackage($basePackage, $alias['alias_normalized'], $alias['alias']);
+            }
             $aliasPackage->setRootPackageAlias(true);
 
             $newIndex = $this->indexCounter++;

src/Composer/DependencyResolver/Rule.php

@@ -13,7 +13,7 @@
 namespace Composer\DependencyResolver;
 
 use Composer\Package\Link;
-use Composer\Package\PackageInterface;
+use Composer\Package\BasePackage;
 use Composer\Package\AliasPackage;
 use Composer\Repository\RepositorySet;
 use Composer\Repository\PlatformRepository;
@@ -47,7 +47,7 @@ abstract class Rule
 
     /**
      * @param int              $reason     A RULE_* constant describing the reason for generating this rule
-     * @param Link|PackageInterface $reasonData
+     * @param Link|BasePackage $reasonData
      */
     public function __construct($reason, $reasonData)
     {
@@ -62,6 +62,8 @@ abstract class Rule
 
     abstract public function getHash();
 
+    abstract public function __toString();
+
     abstract public function equals(Rule $rule);
 
     public function getReason()
@@ -361,7 +363,7 @@ abstract class Rule
         return Problem::getPackageList($packages, $isVerbose);
     }
 
-    private function deduplicateDefaultBranchAlias(PackageInterface $package)
+    private function deduplicateDefaultBranchAlias(BasePackage $package)
     {
         if ($package instanceof AliasPackage && $package->getPrettyVersion() === VersionParser::DEFAULT_BRANCH_ALIAS) {
             $package = $package->getAliasOf();

src/Composer/DependencyResolver/Rule2Literals.php

@@ -12,7 +12,7 @@
 
 namespace Composer\DependencyResolver;
 
-use Composer\Package\PackageInterface;
+use Composer\Package\BasePackage;
 use Composer\Package\Link;
 
 /**
@@ -27,7 +27,7 @@ class Rule2Literals extends Rule
      * @param int                   $literal1
      * @param int                   $literal2
      * @param int                   $reason     A RULE_* constant describing the reason for generating this rule
-     * @param Link|PackageInterface $reasonData
+     * @param Link|BasePackage $reasonData
      */
     public function __construct($literal1, $literal2, $reason, $reasonData)
     {

src/Composer/DependencyResolver/RuleSet.php

@@ -113,6 +113,9 @@ class RuleSet implements \IteratorAggregate, \Countable
         return $this->rules;
     }
 
+    /**
+     * @return RuleSetIterator
+     */
     public function getIterator()
     {
         return new RuleSetIterator($this->getRules());

src/Composer/DependencyResolver/RuleSetGenerator.php

@@ -12,7 +12,7 @@
 
 namespace Composer\DependencyResolver;
 
-use Composer\Package\PackageInterface;
+use Composer\Package\BasePackage;
 use Composer\Package\AliasPackage;
 use Composer\Repository\PlatformRepository;
 
@@ -41,7 +41,7 @@ class RuleSetGenerator
      * This rule is of the form (-A|B|C), where B and C are the providers of
      * one requirement of the package A.
      *
-     * @param  PackageInterface $package    The package with a requirement
+     * @param  BasePackage $package    The package with a requirement
      * @param  array       $providers  The providers of the requirement
      * @param  int         $reason     A RULE_* constant describing the
      *                                      reason for generating this rule
@@ -49,7 +49,7 @@ class RuleSetGenerator
      *                                      that goes with the reason
      * @return Rule|null   The generated rule or null if tautological
      */
-    protected function createRequireRule(PackageInterface $package, array $providers, $reason, $reasonData = null)
+    protected function createRequireRule(BasePackage $package, array $providers, $reason, $reasonData = null)
     {
         $literals = array(-$package->id);
 
@@ -70,7 +70,7 @@ class RuleSetGenerator
      * The rule is (A|B|C) with A, B and C different packages. If the given
      * set of packages is empty an impossible rule is generated.
      *
-     * @param  array $packages   The set of packages to choose from
+     * @param  BasePackage[] $packages   The set of packages to choose from
      * @param  int           $reason     A RULE_* constant describing the reason for
      *                                   generating this rule
      * @param  array         $reasonData Additional data like the root require or fix request info
@@ -92,15 +92,15 @@ class RuleSetGenerator
      * The rule for conflicting packages A and B is (-A|-B). A is called the issuer
      * and B the provider.
      *
-     * @param  PackageInterface $issuer     The package declaring the conflict
+     * @param  BasePackage $issuer     The package declaring the conflict
-     * @param  PackageInterface $provider   The package causing the conflict
+     * @param  BasePackage $provider   The package causing the conflict
      * @param  int         $reason     A RULE_* constant describing the
      *                                      reason for generating this rule
      * @param  mixed       $reasonData Any data, e.g. the package name, that
      *                                      goes with the reason
      * @return Rule|null   The generated rule
      */
-    protected function createRule2Literals(PackageInterface $issuer, PackageInterface $provider, $reason, $reasonData = null)
+    protected function createRule2Literals(BasePackage $issuer, BasePackage $provider, $reason, $reasonData = null)
     {
         // ignore self conflict
         if ($issuer === $provider) {
@@ -142,13 +142,13 @@ class RuleSetGenerator
         $this->rules->add($newRule, $type);
     }
 
-    protected function addRulesForPackage(PackageInterface $package, $ignorePlatformReqs)
+    protected function addRulesForPackage(BasePackage $package, $ignorePlatformReqs)
     {
         $workQueue = new \SplQueue;
         $workQueue->enqueue($package);
 
         while (!$workQueue->isEmpty()) {
-            /** @var PackageInterface $package */
+            /** @var BasePackage $package */
             $package = $workQueue->dequeue();
             if (isset($this->addedMap[$package->id])) {
                 continue;
@@ -192,7 +192,7 @@ class RuleSetGenerator
 
     protected function addConflictRules($ignorePlatformReqs = false)
     {
-        /** @var PackageInterface $package */
+        /** @var BasePackage $package */
         foreach ($this->addedMap as $package) {
             foreach ($package->getConflicts() as $link) {
                 // even if conlict ends up being with an alias, there would be at least one actual package by this name

src/Composer/Downloader/DownloadManager.php

@@ -137,7 +137,7 @@ class DownloadManager
         $installationSource = $package->getInstallationSource();
 
         if ('metapackage' === $package->getType()) {
-            return;
+            return null;
         }
 
         if ('dist' === $installationSource) {
@@ -256,6 +256,8 @@ class DownloadManager
         if ($downloader) {
             return $downloader->prepare($type, $package, $targetDir, $prevPackage);
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -275,6 +277,8 @@ class DownloadManager
         if ($downloader) {
             return $downloader->install($package, $targetDir);
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -295,7 +299,7 @@ class DownloadManager
 
         // no downloaders present means update from metapackage to metapackage, nothing to do
         if (!$initialDownloader && !$downloader) {
-            return;
+            return \React\Promise\resolve();
         }
 
         // if we have a downloader present before, but not after, the package became a metapackage and its files should be removed
@@ -348,6 +352,8 @@ class DownloadManager
         if ($downloader) {
             return $downloader->remove($package, $targetDir);
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -367,6 +373,8 @@ class DownloadManager
         if ($downloader) {
             return $downloader->cleanup($type, $package, $targetDir, $prevPackage);
         }
+
+        return \React\Promise\resolve();
     }
 
     /**

src/Composer/Downloader/FileDownloader.php

@@ -112,8 +112,10 @@ class FileDownloader implements DownloaderInterface, ChangeReportInterface
         };
 
         $retries = 3;
-        $urls = $package->getDistUrls();
+        $distUrls = $package->getDistUrls();
-        foreach ($urls as $index => $url) {
+        /** @var array<array{base: string, processed: string, cacheKey: string}> $urls */
+        $urls = array();
+        foreach ($distUrls as $index => $url) {
             $processedUrl = $this->processUrl($package, $url);
             $urls[$index] = array(
                 'base' => $url,
@@ -140,6 +142,7 @@ class FileDownloader implements DownloaderInterface, ChangeReportInterface
         $accept = null;
         $reject = null;
         $download = function () use ($io, $output, $httpDownloader, $cache, $cacheKeyGenerator, $eventDispatcher, $package, $fileName, &$urls, &$accept, &$reject) {
+            /** @var array{base: string, processed: string, cacheKey: string} $url */
             $url = reset($urls);
             $index = key($urls);
 
@@ -271,6 +274,7 @@ class FileDownloader implements DownloaderInterface, ChangeReportInterface
      */
     public function prepare($type, PackageInterface $package, $path, PackageInterface $prevPackage = null)
     {
+        return \React\Promise\resolve();
     }
 
     /**
@@ -300,6 +304,8 @@ class FileDownloader implements DownloaderInterface, ChangeReportInterface
                 $this->filesystem->removeDirectory($dir);
             }
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -324,6 +330,8 @@ class FileDownloader implements DownloaderInterface, ChangeReportInterface
                 }
             }
         }
+
+        return \React\Promise\resolve();
     }
 
     /**

src/Composer/Downloader/FossilDownloader.php

@@ -25,6 +25,7 @@ class FossilDownloader extends VcsDownloader
      */
     protected function doDownload(PackageInterface $package, $path, $url, PackageInterface $prevPackage = null)
     {
+        return \React\Promise\resolve();
     }
 
     /**
@@ -51,6 +52,8 @@ class FossilDownloader extends VcsDownloader
         if (0 !== $this->process->execute($command, $ignoredOutput, realpath($path))) {
             throw new \RuntimeException('Failed to execute ' . $command . "\n\n" . $this->process->getErrorOutput());
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -72,6 +75,8 @@ class FossilDownloader extends VcsDownloader
         if (0 !== $this->process->execute($command, $ignoredOutput, realpath($path))) {
             throw new \RuntimeException('Failed to execute ' . $command . "\n\n" . $this->process->getErrorOutput());
         }
+
+        return \React\Promise\resolve();
     }
 
     /**

src/Composer/Downloader/GitDownloader.php

@@ -74,6 +74,8 @@ class GitDownloader extends VcsDownloader implements DvcsDownloaderInterface
         } elseif (null === $gitVersion) {
             throw new \RuntimeException('git was not found in your PATH, skipping source download');
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -129,6 +131,8 @@ class GitDownloader extends VcsDownloader implements DvcsDownloaderInterface
             }
             $package->setSourceReference($newRef);
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -192,6 +196,8 @@ class GitDownloader extends VcsDownloader implements DvcsDownloaderInterface
         if ($updateOriginUrl) {
             $this->updateOriginUrl($path, $target->getSourceUrl());
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -201,7 +207,7 @@ class GitDownloader extends VcsDownloader implements DvcsDownloaderInterface
     {
         GitUtil::cleanEnv();
         if (!$this->hasMetadataRepository($path)) {
-            return;
+            return null;
         }
 
         $command = 'git status --porcelain --untracked-files=no';
@@ -217,7 +223,7 @@ class GitDownloader extends VcsDownloader implements DvcsDownloaderInterface
         GitUtil::cleanEnv();
         $path = $this->normalizePath($path);
         if (!$this->hasMetadataRepository($path)) {
-            return;
+            return null;
         }
 
         $command = 'git show-ref --head -d';
@@ -228,13 +234,13 @@ class GitDownloader extends VcsDownloader implements DvcsDownloaderInterface
         $refs = trim($output);
         if (!preg_match('{^([a-f0-9]+) HEAD$}mi', $refs, $match)) {
             // could not match the HEAD for some reason
-            return;
+            return null;
         }
 
         $headRef = $match[1];
         if (!preg_match_all('{^'.$headRef.' refs/heads/(.+)$}mi', $refs, $matches)) {
             // not on a branch, we are either on a not-modified tag or some sort of detached head, so skip this
-            return;
+            return null;
         }
 
         $candidateBranches = $matches[1];

src/Composer/Downloader/GzipDownloader.php

@@ -33,14 +33,14 @@ class GzipDownloader extends ArchiveDownloader
             $command = 'gzip -cd ' . ProcessExecutor::escape($file) . ' > ' . ProcessExecutor::escape($targetFilepath);
 
             if (0 === $this->process->execute($command, $ignoredOutput)) {
-                return;
+                return \React\Promise\resolve();
             }
 
             if (extension_loaded('zlib')) {
                 // Fallback to using the PHP extension.
                 $this->extractUsingExt($file, $targetFilepath);
 
-                return;
+                return \React\Promise\resolve();
             }
 
             $processError = 'Failed to execute ' . $command . "\n\n" . $this->process->getErrorOutput();
@@ -49,6 +49,8 @@ class GzipDownloader extends ArchiveDownloader
 
         // Windows version of PHP has built-in support of gzip functions
         $this->extractUsingExt($file, $targetFilepath);
+
+        return \React\Promise\resolve();
     }
 
     private function extractUsingExt($file, $targetFilepath)

src/Composer/Downloader/HgDownloader.php

@@ -29,6 +29,8 @@ class HgDownloader extends VcsDownloader
         if (null === HgUtils::getVersion($this->process)) {
             throw new \RuntimeException('hg was not found in your PATH, skipping source download');
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -49,6 +51,8 @@ class HgDownloader extends VcsDownloader
         if (0 !== $this->process->execute($command, $ignoredOutput, realpath($path))) {
             throw new \RuntimeException('Failed to execute ' . $command . "\n\n" . $this->process->getErrorOutput());
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -70,6 +74,8 @@ class HgDownloader extends VcsDownloader
         };
 
         $hgUtils->runCommand($command, $url, $path);
+
+        return \React\Promise\resolve();
     }
 
     /**

src/Composer/Downloader/PathDownloader.php

@@ -52,7 +52,7 @@ class PathDownloader extends FileDownloader implements VcsCapableDownloaderInter
         }
 
         if (realpath($path) === $realUrl) {
-            return;
+            return \React\Promise\resolve();
         }
 
         if (strpos(realpath($path) . DIRECTORY_SEPARATOR, $realUrl . DIRECTORY_SEPARATOR) === 0) {
@@ -67,6 +67,8 @@ class PathDownloader extends FileDownloader implements VcsCapableDownloaderInter
                 $realUrl
             ));
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -83,7 +85,7 @@ class PathDownloader extends FileDownloader implements VcsCapableDownloaderInter
                 $this->io->writeError("  - " . InstallOperation::format($package) . $this->getInstallOperationAppendix($package, $path));
             }
 
-            return;
+            return \React\Promise\resolve();
         }
 
         // Get the transport options with default values
@@ -151,6 +153,8 @@ class PathDownloader extends FileDownloader implements VcsCapableDownloaderInter
         if ($output) {
             $this->io->writeError('');
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -176,13 +180,19 @@ class PathDownloader extends FileDownloader implements VcsCapableDownloaderInter
                 $this->io->writeError("    <warning>Could not remove junction at " . $path . " - is another process locking it?</warning>");
                 throw new \RuntimeException('Could not reliably remove junction for package ' . $package->getName());
             }
-        } elseif (realpath($path) === realpath($package->getDistUrl())) {
+
+            return \React\Promise\resolve();
+        }
+
+        if (realpath($path) === realpath($package->getDistUrl())) {
             if ($output) {
                 $this->io->writeError("  - " . UninstallOperation::format($package).", source is still present in $path");
             }
-        } else {
+
-            return parent::remove($package, $path, $output);
+            return \React\Promise\resolve();
         }
+
+        return parent::remove($package, $path, $output);
     }
 
     /**
@@ -199,6 +209,8 @@ class PathDownloader extends FileDownloader implements VcsCapableDownloaderInter
         if ($packageVersion = $guesser->guessVersion($packageConfig, $path)) {
             return $packageVersion['commit'];
         }
+
+        return null;
     }
 
     /**

src/Composer/Downloader/PerforceDownloader.php

@@ -29,6 +29,7 @@ class PerforceDownloader extends VcsDownloader
      */
     protected function doDownload(PackageInterface $package, $path, $url, PackageInterface $prevPackage = null)
     {
+        return \React\Promise\resolve();
     }
 
     /**
@@ -47,6 +48,8 @@ class PerforceDownloader extends VcsDownloader
         $this->perforce->connectClient();
         $this->perforce->syncCodeBase($label);
         $this->perforce->cleanupClientSpec();
+
+        return \React\Promise\resolve();
     }
 
     private function getLabelFromSourceReference($ref)
@@ -85,7 +88,7 @@ class PerforceDownloader extends VcsDownloader
      */
     protected function doUpdate(PackageInterface $initial, PackageInterface $target, $path, $url)
     {
-        $this->doInstall($target, $path, $url);
+        return $this->doInstall($target, $path, $url);
     }
 
     /**
@@ -94,6 +97,8 @@ class PerforceDownloader extends VcsDownloader
     public function getLocalChanges(PackageInterface $package, $path)
     {
         $this->io->writeError('Perforce driver does not check for local changes before overriding');
+
+        return null;
     }
 
     /**

src/Composer/Downloader/PharDownloader.php

@@ -34,5 +34,7 @@ class PharDownloader extends ArchiveDownloader
          * https://github.com/koto/phar-util
          * http://blog.kotowicz.net/2010/08/hardening-php-how-to-securely-include.html
          */
+
+        return \React\Promise\resolve();
     }
 }

src/Composer/Downloader/RarDownloader.php

@@ -36,7 +36,7 @@ class RarDownloader extends ArchiveDownloader
             $command = 'unrar x ' . ProcessExecutor::escape($file) . ' ' . ProcessExecutor::escape($path) . ' >/dev/null && chmod -R u+w ' . ProcessExecutor::escape($path);
 
             if (0 === $this->process->execute($command, $ignoredOutput)) {
-                return;
+                return \React\Promise\resolve();
             }
 
             $processError = 'Failed to execute ' . $command . "\n\n" . $this->process->getErrorOutput();
@@ -75,5 +75,7 @@ class RarDownloader extends ArchiveDownloader
         }
 
         $rarArchive->close();
+
+        return \React\Promise\resolve();
    }
 }

src/Composer/Downloader/SvnDownloader.php

@@ -35,6 +35,8 @@ class SvnDownloader extends VcsDownloader
         if (null === $util->binaryVersion()) {
             throw new \RuntimeException('svn was not found in your PATH, skipping source download');
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -55,6 +57,8 @@ class SvnDownloader extends VcsDownloader
 
         $this->io->writeError(" Checking out ".$package->getSourceReference());
         $this->execute($package, $url, "svn co", sprintf("%s/%s", $url, $ref), null, $path);
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -77,6 +81,8 @@ class SvnDownloader extends VcsDownloader
 
         $this->io->writeError(" Checking out " . $ref);
         $this->execute($target, $url, "svn switch" . $flags, sprintf("%s/%s", $url, $ref), $path);
+
+        return \React\Promise\resolve();
     }
 
     /**

src/Composer/Downloader/TarDownloader.php

@@ -29,5 +29,7 @@ class TarDownloader extends ArchiveDownloader
         // Can throw an UnexpectedValueException
         $archive = new \PharData($file);
         $archive->extractTo($path, null, true);
+
+        return \React\Promise\resolve();
     }
 }

src/Composer/Downloader/VcsDownloader.php

@@ -86,6 +86,8 @@ abstract class VcsDownloader implements DownloaderInterface, ChangeReportInterfa
                 }
             }
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -101,6 +103,8 @@ abstract class VcsDownloader implements DownloaderInterface, ChangeReportInterfa
         } elseif ($type === 'uninstall') {
             $this->cleanChanges($package, $path, false);
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -112,6 +116,8 @@ abstract class VcsDownloader implements DownloaderInterface, ChangeReportInterfa
             $this->reapplyChanges($path);
             unset($this->hasCleanedChanges[$prevPackage->getUniqueName()]);
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -145,6 +151,8 @@ abstract class VcsDownloader implements DownloaderInterface, ChangeReportInterfa
                 }
             }
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -207,6 +215,8 @@ abstract class VcsDownloader implements DownloaderInterface, ChangeReportInterfa
         if (!$urls && $exception) {
             throw $exception;
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -238,6 +248,8 @@ abstract class VcsDownloader implements DownloaderInterface, ChangeReportInterfa
         if ($packageVersion = $guesser->guessVersion($packageConfig, $path)) {
             return $packageVersion['commit'];
         }
+
+        return null;
     }
 
     /**
@@ -255,6 +267,8 @@ abstract class VcsDownloader implements DownloaderInterface, ChangeReportInterfa
         if (null !== $this->getLocalChanges($package, $path)) {
             throw new \RuntimeException('Source directory ' . $path . ' has uncommitted changes.');
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -321,6 +335,9 @@ abstract class VcsDownloader implements DownloaderInterface, ChangeReportInterfa
      */
     abstract protected function hasMetadataRepository($path);
 
+    /**
+     * @return string[]
+     */
     private function prepareUrls(array $urls)
     {
         foreach ($urls as $index => $url) {

src/Composer/Downloader/XzDownloader.php

@@ -28,7 +28,7 @@ class XzDownloader extends ArchiveDownloader
         $command = 'tar -xJf ' . ProcessExecutor::escape($file) . ' -C ' . ProcessExecutor::escape($path);
 
         if (0 === $this->process->execute($command, $ignoredOutput)) {
-            return;
+            return \React\Promise\resolve();
         }
 
         $processError = 'Failed to execute ' . $command . "\n\n" . $this->process->getErrorOutput();

src/Composer/Downloader/ZipDownloader.php

@@ -17,6 +17,7 @@ use Composer\Util\IniHelper;
 use Composer\Util\Platform;
 use Composer\Util\ProcessExecutor;
 use Symfony\Component\Process\ExecutableFinder;
+use React\Promise\PromiseInterface;
 use ZipArchive;
 
 /**
@@ -72,6 +73,7 @@ class ZipDownloader extends ArchiveDownloader
      * @param  string           $file         File to extract
      * @param  string           $path         Path where to extract file
      * @param  bool             $isLastChance If true it is called as a fallback and should throw an exception
+     * @return PromiseInterface
      */
     private function extractWithSystemUnzip(PackageInterface $package, $file, $path, $isLastChance, $async = false)
     {
@@ -157,6 +159,7 @@ class ZipDownloader extends ArchiveDownloader
      * @param  string           $file         File to extract
      * @param  string           $path         Path where to extract file
      * @param  bool             $isLastChance If true it is called as a fallback and should throw an exception
+     * @return PromiseInterface
      *
      * TODO v3 should make this private once we can drop PHP 5.3 support
      * @protected
@@ -214,6 +217,7 @@ class ZipDownloader extends ArchiveDownloader
      *
      * @param  string                $file File to extract
      * @param  string                $path Path where to extract file
+     * @return PromiseInterface|null
      *
      * TODO v3 should make this private once we can drop PHP 5.3 support
      * @protected

src/Composer/EventDispatcher/EventDispatcher.php

@@ -24,7 +24,7 @@ use Composer\Installer\PackageEvent;
 use Composer\Installer\BinaryInstaller;
 use Composer\Util\ProcessExecutor;
 use Composer\Script\Event as ScriptEvent;
-use Composer\ClassLoader;
+use Composer\Autoload\ClassLoader;
 use Symfony\Component\Process\PhpExecutableFinder;
 use Symfony\Component\Process\ExecutableFinder;
 

src/Composer/IO/BaseIO.php

@@ -154,119 +154,71 @@ abstract class BaseIO implements IOInterface
     }
 
     /**
-     * System is unusable.
+     * {@inheritDoc}
-     *
-     * @param  string $message
-     * @param  array  $context
-     * @return null
      */
     public function emergency($message, array $context = array())
     {
-        return $this->log(LogLevel::EMERGENCY, $message, $context);
+        $this->log(LogLevel::EMERGENCY, $message, $context);
     }
 
     /**
-     * Action must be taken immediately.
+     * {@inheritDoc}
-     *
-     * Example: Entire website down, database unavailable, etc. This should
-     * trigger the SMS alerts and wake you up.
-     *
-     * @param  string $message
-     * @param  array  $context
-     * @return null
      */
     public function alert($message, array $context = array())
     {
-        return $this->log(LogLevel::ALERT, $message, $context);
+        $this->log(LogLevel::ALERT, $message, $context);
     }
 
     /**
-     * Critical conditions.
+     * {@inheritDoc}
-     *
-     * Example: Application component unavailable, unexpected exception.
-     *
-     * @param  string $message
-     * @param  array  $context
-     * @return null
      */
     public function critical($message, array $context = array())
     {
-        return $this->log(LogLevel::CRITICAL, $message, $context);
+        $this->log(LogLevel::CRITICAL, $message, $context);
     }
 
     /**
-     * Runtime errors that do not require immediate action but should typically
+     * {@inheritDoc}
-     * be logged and monitored.
-     *
-     * @param  string $message
-     * @param  array  $context
-     * @return null
      */
     public function error($message, array $context = array())
     {
-        return $this->log(LogLevel::ERROR, $message, $context);
+        $this->log(LogLevel::ERROR, $message, $context);
     }
 
     /**
-     * Exceptional occurrences that are not errors.
+     * {@inheritDoc}
-     *
-     * Example: Use of deprecated APIs, poor use of an API, undesirable things
-     * that are not necessarily wrong.
-     *
-     * @param  string $message
-     * @param  array  $context
-     * @return null
      */
     public function warning($message, array $context = array())
     {
-        return $this->log(LogLevel::WARNING, $message, $context);
+        $this->log(LogLevel::WARNING, $message, $context);
     }
 
     /**
-     * Normal but significant events.
+     * {@inheritDoc}
-     *
-     * @param  string $message
-     * @param  array  $context
-     * @return null
      */
     public function notice($message, array $context = array())
     {
-        return $this->log(LogLevel::NOTICE, $message, $context);
+        $this->log(LogLevel::NOTICE, $message, $context);
     }
 
     /**
-     * Interesting events.
+     * {@inheritDoc}
-     *
-     * Example: User logs in, SQL logs.
-     *
-     * @param  string $message
-     * @param  array  $context
-     * @return null
      */
     public function info($message, array $context = array())
     {
-        return $this->log(LogLevel::INFO, $message, $context);
+        $this->log(LogLevel::INFO, $message, $context);
     }
 
     /**
-     * Detailed debug information.
+     * {@inheritDoc}
-     *
-     * @param  string $message
-     * @param  array  $context
-     * @return null
      */
     public function debug($message, array $context = array())
     {
-        return $this->log(LogLevel::DEBUG, $message, $context);
+        $this->log(LogLevel::DEBUG, $message, $context);
     }
 
     /**
-     * Logs with an arbitrary level.
+     * {@inheritDoc}
-     *
-     * @param  mixed  $level
-     * @param  string $message
-     * @param  array  $context
-     * @return null
      */
     public function log($level, $message, array $context = array())
     {

src/Composer/IO/BufferIO.php

@@ -24,6 +24,11 @@ use Symfony\Component\Console\Helper\HelperSet;
  */
 class BufferIO extends ConsoleIO
 {
+    /** @var StringInput */
+    protected $input;
+    /** @var StreamOutput */
+    protected $output;
+
     /**
      * @param string                        $input
      * @param int                           $verbosity

src/Composer/IO/NullIO.php

@@ -106,7 +106,7 @@ class NullIO extends BaseIO
     /**
      * {@inheritDoc}
      */
-    public function askAndValidate($question, $validator, $attempts = false, $default = null)
+    public function askAndValidate($question, $validator, $attempts = null, $default = null)
     {
         return $default;
     }

src/Composer/Installer.php

@@ -135,13 +135,14 @@ class Installer
     protected $writeLock;
     protected $executeOperations = true;
 
+    /** @var bool */
+    protected $updateMirrors = false;
     /**
      * Array of package names/globs flagged for update
      *
      * @var array|null
      */
-    protected $updateMirrors = false;
+    protected $updateAllowList = null;
-    protected $updateAllowList;
     protected $updateAllowTransitiveDependencies = Request::UPDATE_ONLY_LISTED;
 
     /**
@@ -918,7 +919,8 @@ class Installer
         foreach ($packages as $key => $package) {
             if ($package instanceof AliasPackage) {
                 $alias = (string) $package->getAliasOf();
-                $packages[$key] = new AliasPackage($packages[$alias], $package->getVersion(), $package->getPrettyVersion());
+                $className = get_class($package);
+                $packages[$key] = new $className($packages[$alias], $package->getVersion(), $package->getPrettyVersion());
             }
         }
         $rm->setLocalRepository(

src/Composer/Installer/InstallationManager.php

@@ -172,12 +172,12 @@ class InstallationManager
     /**
      * Executes solver operation.
      *
-     * @param RepositoryInterface  $repo       repository in which to add/remove/update packages
+     * @param InstalledRepositoryInterface $repo       repository in which to add/remove/update packages
      * @param OperationInterface[]         $operations operations to execute
      * @param bool                         $devMode    whether the install is being run in dev mode
      * @param bool                         $runScripts whether to dispatch script events
      */
-    public function execute(RepositoryInterface $repo, array $operations, $devMode = true, $runScripts = true)
+    public function execute(InstalledRepositoryInterface $repo, array $operations, $devMode = true, $runScripts = true)
     {
         $cleanupPromises = array();
 
@@ -243,8 +243,8 @@ class InstallationManager
             $batches = array();
             $batch = array();
             foreach ($operations as $index => $operation) {
-                if (in_array($operation->getOperationType(), array('update', 'install'), true)) {
+                if ($operation instanceof UpdateOperation || $operation instanceof InstallOperation) {
-                    $package = $operation->getOperationType() === 'update' ? $operation->getTargetPackage() : $operation->getPackage();
+                    $package = $operation instanceof UpdateOperation ? $operation->getTargetPackage() : $operation->getPackage();
                     if ($package->getType() === 'composer-plugin' && ($extra = $package->getExtra()) && isset($extra['plugin-modifies-downloads']) && $extra['plugin-modifies-downloads'] === true) {
                         if ($batch) {
                             $batches[] = $batch;
@@ -272,7 +272,7 @@ class InstallationManager
                 pcntl_signal(SIGINT, $prevHandler);
             }
             if ($handleInterruptsWindows) {
-                sapi_windows_set_ctrl_handler($prevHandler, false);
+                sapi_windows_set_ctrl_handler($windowsHandler, false);
             }
 
             throw $e;
@@ -282,7 +282,7 @@ class InstallationManager
             pcntl_signal(SIGINT, $prevHandler);
         }
         if ($handleInterruptsWindows) {
-            sapi_windows_set_ctrl_handler($prevHandler, false);
+            sapi_windows_set_ctrl_handler($windowsHandler, false);
         }
 
         // do a last write so that we write the repository even if nothing changed
@@ -295,7 +295,7 @@ class InstallationManager
      * @param array $operations    List of operations to execute in this batch
      * @param array $allOperations Complete list of operations to be executed in the install job, used for event listeners
      */
-    private function downloadAndExecuteBatch(RepositoryInterface $repo, array $operations, array &$cleanupPromises, $devMode, $runScripts, array $allOperations)
+    private function downloadAndExecuteBatch(InstalledRepositoryInterface $repo, array $operations, array &$cleanupPromises, $devMode, $runScripts, array $allOperations)
     {
         $promises = array();
 
@@ -372,7 +372,7 @@ class InstallationManager
      * @param array $operations    List of operations to execute in this batch
      * @param array $allOperations Complete list of operations to be executed in the install job, used for event listeners
      */
-    private function executeBatch(RepositoryInterface $repo, array $operations, array $cleanupPromises, $devMode, $runScripts, array $allOperations)
+    private function executeBatch(InstalledRepositoryInterface $repo, array $operations, array $cleanupPromises, $devMode, $runScripts, array $allOperations)
     {
         $promises = array();
         $postExecCallbacks = array();
@@ -460,10 +460,10 @@ class InstallationManager
     /**
      * Executes install operation.
      *
-     * @param RepositoryInterface $repo      repository in which to check
+     * @param InstalledRepositoryInterface $repo      repository in which to check
      * @param InstallOperation             $operation operation instance
      */
-    public function install(RepositoryInterface $repo, InstallOperation $operation)
+    public function install(InstalledRepositoryInterface $repo, InstallOperation $operation)
     {
         $package = $operation->getPackage();
         $installer = $this->getInstaller($package->getType());
@@ -476,10 +476,10 @@ class InstallationManager
     /**
      * Executes update operation.
      *
-     * @param RepositoryInterface $repo      repository in which to check
+     * @param InstalledRepositoryInterface $repo      repository in which to check
      * @param UpdateOperation              $operation operation instance
      */
-    public function update(RepositoryInterface $repo, UpdateOperation $operation)
+    public function update(InstalledRepositoryInterface $repo, UpdateOperation $operation)
     {
         $initial = $operation->getInitialPackage();
         $target = $operation->getTargetPackage();
@@ -509,10 +509,10 @@ class InstallationManager
     /**
      * Uninstalls package.
      *
-     * @param RepositoryInterface $repo      repository in which to check
+     * @param InstalledRepositoryInterface $repo      repository in which to check
      * @param UninstallOperation           $operation operation instance
      */
-    public function uninstall(RepositoryInterface $repo, UninstallOperation $operation)
+    public function uninstall(InstalledRepositoryInterface $repo, UninstallOperation $operation)
     {
         $package = $operation->getPackage();
         $installer = $this->getInstaller($package->getType());
@@ -523,10 +523,10 @@ class InstallationManager
     /**
      * Executes markAliasInstalled operation.
      *
-     * @param RepositoryInterface         $repo      repository in which to check
+     * @param InstalledRepositoryInterface $repo      repository in which to check
      * @param MarkAliasInstalledOperation  $operation operation instance
      */
-    public function markAliasInstalled(RepositoryInterface $repo, MarkAliasInstalledOperation $operation)
+    public function markAliasInstalled(InstalledRepositoryInterface $repo, MarkAliasInstalledOperation $operation)
     {
         $package = $operation->getPackage();
 
@@ -538,10 +538,10 @@ class InstallationManager
     /**
      * Executes markAlias operation.
      *
-     * @param RepositoryInterface           $repo      repository in which to check
+     * @param InstalledRepositoryInterface  $repo      repository in which to check
      * @param MarkAliasUninstalledOperation $operation operation instance
      */
-    public function markAliasUninstalled(RepositoryInterface $repo, MarkAliasUninstalledOperation $operation)
+    public function markAliasUninstalled(InstalledRepositoryInterface $repo, MarkAliasUninstalledOperation $operation)
     {
         $package = $operation->getPackage();
 

src/Composer/Installer/MetapackageInstaller.php

@@ -55,6 +55,7 @@ class MetapackageInstaller implements InstallerInterface
     public function download(PackageInterface $package, PackageInterface $prevPackage = null)
     {
         // noop
+        return \React\Promise\resolve();
     }
 
     /**
@@ -63,6 +64,7 @@ class MetapackageInstaller implements InstallerInterface
     public function prepare($type, PackageInterface $package, PackageInterface $prevPackage = null)
     {
         // noop
+        return \React\Promise\resolve();
     }
 
     /**
@@ -71,6 +73,7 @@ class MetapackageInstaller implements InstallerInterface
     public function cleanup($type, PackageInterface $package, PackageInterface $prevPackage = null)
     {
         // noop
+        return \React\Promise\resolve();
     }
 
     /**
@@ -81,6 +84,8 @@ class MetapackageInstaller implements InstallerInterface
         $this->io->writeError("  - " . InstallOperation::format($package));
 
         $repo->addPackage(clone $package);
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -96,6 +101,8 @@ class MetapackageInstaller implements InstallerInterface
 
         $repo->removePackage($initial);
         $repo->addPackage(clone $target);
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -110,6 +117,8 @@ class MetapackageInstaller implements InstallerInterface
         $this->io->writeError("  - " . UninstallOperation::format($package));
 
         $repo->removePackage($package);
+
+        return \React\Promise\resolve();
     }
 
     /**

src/Composer/Installer/NoopInstaller.php

@@ -45,6 +45,7 @@ class NoopInstaller implements InstallerInterface
      */
     public function download(PackageInterface $package, PackageInterface $prevPackage = null)
     {
+        return \React\Promise\resolve();
     }
 
     /**
@@ -52,6 +53,7 @@ class NoopInstaller implements InstallerInterface
      */
     public function prepare($type, PackageInterface $package, PackageInterface $prevPackage = null)
     {
+        return \React\Promise\resolve();
     }
 
     /**
@@ -59,6 +61,7 @@ class NoopInstaller implements InstallerInterface
      */
     public function cleanup($type, PackageInterface $package, PackageInterface $prevPackage = null)
     {
+        return \React\Promise\resolve();
     }
 
     /**
@@ -69,6 +72,8 @@ class NoopInstaller implements InstallerInterface
         if (!$repo->hasPackage($package)) {
             $repo->addPackage(clone $package);
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -84,6 +89,8 @@ class NoopInstaller implements InstallerInterface
         if (!$repo->hasPackage($target)) {
             $repo->addPackage(clone $target);
         }
+
+        return \React\Promise\resolve();
     }
 
     /**
@@ -95,6 +102,8 @@ class NoopInstaller implements InstallerInterface
             throw new \InvalidArgumentException('Package is not installed: '.$package);
         }
         $repo->removePackage($package);
+
+        return \React\Promise\resolve();
     }
 
     /**

src/Composer/Installer/SuggestedPackagesReporter.php

@@ -101,7 +101,7 @@ class SuggestedPackagesReporter
      * @param  int                       $mode             One of the MODE_* constants from this class
      * @param  InstalledRepository|null  $installedRepo    If passed in, suggested packages which are installed already will be skipped
      * @param  PackageInterface|null     $onlyDependentsOf If passed in, only the suggestions from direct dependents of that package, or from the package itself, will be shown
-     * @return SuggestedPackagesReporter
+     * @return void
      */
     public function output($mode, InstalledRepository $installedRepo = null, PackageInterface $onlyDependentsOf = null)
     {
@@ -122,7 +122,7 @@ class SuggestedPackagesReporter
                 $this->io->write(sprintf('<info>%s</info>', $name));
             }
 
-            return 0;
+            return;
         }
 
         // Grouped by package
@@ -160,8 +160,6 @@ class SuggestedPackagesReporter
                 $this->io->write('<info>'.$diff.' additional suggestions</info> by transitive dependencies can be shown with <info>--all</info>');
             }
         }
-
-        return $this;
     }
 
     /**
@@ -169,7 +167,7 @@ class SuggestedPackagesReporter
      *
      * @param  InstalledRepository|null  $installedRepo    If passed in, suggested packages which are installed already will be skipped
      * @param  PackageInterface|null     $onlyDependentsOf If passed in, only the suggestions from direct dependents of that package, or from the package itself, will be shown
-     * @return SuggestedPackagesReporter
+     * @return void
      */
     public function outputMinimalistic(InstalledRepository $installedRepo = null, PackageInterface $onlyDependentsOf = null)
     {
@@ -177,8 +175,6 @@ class SuggestedPackagesReporter
         if ($suggestedPackages) {
             $this->io->writeError('<info>'.count($suggestedPackages).' package suggestions were added by new dependencies, use `composer suggest` to see details.</info>');
         }
-
-        return $this;
     }
 
     /**

src/Composer/Package/AliasPackage.php

@@ -18,7 +18,7 @@ use Composer\Package\Version\VersionParser;
 /**
  * @author Jordi Boggiano <j.boggiano@seld.be>
  */
-class AliasPackage extends BasePackage implements CompletePackageInterface
+class AliasPackage extends BasePackage
 {
     protected $version;
     protected $prettyVersion;
@@ -27,7 +27,7 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
     protected $stability;
     protected $hasSelfVersionRequires = false;
 
-    /** @var PackageInterface */
+    /** @var BasePackage */
     protected $aliasOf;
     /** @var Link[] */
     protected $requires;
@@ -43,11 +43,11 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
     /**
      * All descendants' constructors should call this parent constructor
      *
-     * @param PackageInterface $aliasOf       The package this package is an alias of
+     * @param BasePackage      $aliasOf       The package this package is an alias of
      * @param string           $version       The version the alias must report
      * @param string           $prettyVersion The alias's non-normalized version
      */
-    public function __construct(PackageInterface $aliasOf, $version, $prettyVersion)
+    public function __construct(BasePackage $aliasOf, $version, $prettyVersion)
     {
         parent::__construct($aliasOf->getName());
 
@@ -64,7 +64,7 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
     }
 
     /**
-     * @return PackageInterface
+     * @return BasePackage
      */
     public function getAliasOf()
     {
@@ -210,6 +210,11 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
         return $this->hasSelfVersionRequires;
     }
 
+    public function __toString()
+    {
+        return parent::__toString().' ('.($this->rootPackageAlias ? 'root ' : ''). 'alias of '.$this->aliasOf->getVersion().')';
+    }
+
     /***************************************
      * Wrappers around the aliased package *
      ***************************************/
@@ -261,12 +266,12 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
 
     public function setSourceReference($reference)
     {
-        return $this->aliasOf->setSourceReference($reference);
+        $this->aliasOf->setSourceReference($reference);
     }
 
     public function setSourceMirrors($mirrors)
     {
-        return $this->aliasOf->setSourceMirrors($mirrors);
+        $this->aliasOf->setSourceMirrors($mirrors);
     }
 
     public function getSourceMirrors()
@@ -296,7 +301,7 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
 
     public function setDistReference($reference)
     {
-        return $this->aliasOf->setDistReference($reference);
+        $this->aliasOf->setDistReference($reference);
     }
 
     public function getDistSha1Checksum()
@@ -306,7 +311,7 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
 
     public function setTransportOptions(array $options)
     {
-        return $this->aliasOf->setTransportOptions($options);
+        $this->aliasOf->setTransportOptions($options);
     }
 
     public function getTransportOptions()
@@ -316,7 +321,7 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
 
     public function setDistMirrors($mirrors)
     {
-        return $this->aliasOf->setDistMirrors($mirrors);
+        $this->aliasOf->setDistMirrors($mirrors);
     }
 
     public function getDistMirrors()
@@ -324,16 +329,6 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
         return $this->aliasOf->getDistMirrors();
     }
 
-    public function getScripts()
-    {
-        return $this->aliasOf->getScripts();
-    }
-
-    public function getLicense()
-    {
-        return $this->aliasOf->getLicense();
-    }
-
     public function getAutoload()
     {
         return $this->aliasOf->getAutoload();
@@ -349,11 +344,6 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
         return $this->aliasOf->getIncludePaths();
     }
 
-    public function getRepositories()
-    {
-        return $this->aliasOf->getRepositories();
-    }
-
     public function getReleaseDate()
     {
         return $this->aliasOf->getReleaseDate();
@@ -364,88 +354,33 @@ class AliasPackage extends BasePackage implements CompletePackageInterface
         return $this->aliasOf->getBinaries();
     }
 
-    public function getKeywords()
-    {
-        return $this->aliasOf->getKeywords();
-    }
-
-    public function getDescription()
-    {
-        return $this->aliasOf->getDescription();
-    }
-
-    public function getHomepage()
-    {
-        return $this->aliasOf->getHomepage();
-    }
-
     public function getSuggests()
     {
         return $this->aliasOf->getSuggests();
     }
 
-    public function getAuthors()
-    {
-        return $this->aliasOf->getAuthors();
-    }
-
-    public function getSupport()
-    {
-        return $this->aliasOf->getSupport();
-    }
-
-    public function getFunding()
-    {
-        return $this->aliasOf->getFunding();
-    }
-
     public function getNotificationUrl()
     {
         return $this->aliasOf->getNotificationUrl();
     }
 
-    public function getArchiveName()
-    {
-        return $this->aliasOf->getArchiveName();
-    }
-
-    public function getArchiveExcludes()
-    {
-        return $this->aliasOf->getArchiveExcludes();
-    }
-
     public function isDefaultBranch()
     {
         return $this->aliasOf->isDefaultBranch();
     }
 
-    public function isAbandoned()
-    {
-        return $this->aliasOf->isAbandoned();
-    }
-
-    public function getReplacementPackage()
-    {
-        return $this->aliasOf->getReplacementPackage();
-    }
-
-    public function __toString()
-    {
-        return parent::__toString().' ('.($this->rootPackageAlias ? 'root ' : ''). 'alias of '.$this->aliasOf->getVersion().')';
-    }
-
     public function setDistUrl($url)
     {
-        return $this->aliasOf->setDistUrl($url);
+        $this->aliasOf->setDistUrl($url);
     }
 
     public function setDistType($type)
     {
-        return $this->aliasOf->setDistType($type);
+        $this->aliasOf->setDistType($type);
     }
 
     public function setSourceDistReferences($reference)
     {
-        return $this->aliasOf->setSourceDistReferences($reference);
+        $this->aliasOf->setSourceDistReferences($reference);
     }
 }

src/Composer/Package/Archiver/ArchiveManager.php

@@ -18,6 +18,7 @@ use Composer\Package\RootPackageInterface;
 use Composer\Util\Filesystem;
 use Composer\Util\Loop;
 use Composer\Json\JsonFile;
+use Composer\Package\CompletePackageInterface;
 
 /**
  * @author Matthieu Moquet <matthieu@moquet.net>
@@ -74,11 +75,11 @@ class ArchiveManager
     /**
      * Generate a distinct filename for a particular version of a package.
      *
-     * @param PackageInterface $package The package to get a name for
+     * @param CompletePackageInterface $package The package to get a name for
      *
      * @return string A filename without an extension
      */
-    public function getPackageFilename(PackageInterface $package)
+    public function getPackageFilename(CompletePackageInterface $package)
     {
         if ($package->getArchiveName()) {
             $baseName = $package->getArchiveName();
@@ -107,7 +108,7 @@ class ArchiveManager
     /**
      * Create an archive of the specified package.
      *
-     * @param  PackageInterface          $package       The package to archive
+     * @param  CompletePackageInterface  $package       The package to archive
      * @param  string                    $format        The format of the archive (zip, tar, ...)
      * @param  string                    $targetDir     The directory where to build the archive
      * @param  string|null               $fileName      The relative file name to use for the archive, or null to generate
@@ -117,7 +118,7 @@ class ArchiveManager
      * @throws \RuntimeException
      * @return string                    The path of the created archive
      */
-    public function archive(PackageInterface $package, $format, $targetDir, $fileName = null, $ignoreFilters = false)
+    public function archive(CompletePackageInterface $package, $format, $targetDir, $fileName = null, $ignoreFilters = false)
     {
         if (empty($format)) {
             throw new \InvalidArgumentException('Format must be specified');

src/Composer/Package/BasePackage.php

@@ -23,7 +23,7 @@ use Composer\Repository\PlatformRepository;
 abstract class BasePackage implements PackageInterface
 {
     /**
-     * @phpstan-var array<string, array{description: string, method: Link::TYPE_*}>
+     * @psalm-var array<string, array{description: string, method: Link::TYPE_*}>
      */
     public static $supportedLinkTypes = array(
         'require' => array('description' => 'requires', 'method' => Link::TYPE_REQUIRE),
@@ -50,16 +50,16 @@ abstract class BasePackage implements PackageInterface
     /**
      * READ-ONLY: The package id, public for fast access in dependency solver
      * @var int
+     * @internal
+     * @readonly
      */
     public $id;
     /** @var string */
     protected $name;
     /** @var string */
     protected $prettyName;
-    /** @var RepositoryInterface */
+    /** @var ?RepositoryInterface */
-    protected $repository;
+    protected $repository = null;
-    /** @var array */
-    protected $transportOptions = array();
 
     /**
      * All descendants' constructors should call this parent constructor
@@ -146,24 +146,6 @@ abstract class BasePackage implements PackageInterface
         return $this->repository;
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public function getTransportOptions()
-    {
-        return $this->transportOptions;
-    }
-
-    /**
-     * Configures the list of options to download package dist files
-     *
-     * @param array $options
-     */
-    public function setTransportOptions(array $options)
-    {
-        $this->transportOptions = $options;
-    }
-
     /**
      * checks if this package is a platform package
      *

src/Composer/Package/CompleteAliasPackage.php

@@ -0,0 +1,167 @@
+<?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\Package;
+
+/**
+ * @author Jordi Boggiano <j.boggiano@seld.be>
+ */
+class CompleteAliasPackage extends AliasPackage implements CompletePackageInterface
+{
+    /** @var CompletePackage */
+    protected $aliasOf;
+
+    /**
+     * All descendants' constructors should call this parent constructor
+     *
+     * @param CompletePackage $aliasOf       The package this package is an alias of
+     * @param string                   $version       The version the alias must report
+     * @param string                   $prettyVersion The alias's non-normalized version
+     */
+    public function __construct(CompletePackage $aliasOf, $version, $prettyVersion)
+    {
+        parent::__construct($aliasOf, $version, $prettyVersion);
+    }
+
+    /**
+     * @return CompletePackage
+     */
+    public function getAliasOf()
+    {
+        return $this->aliasOf;
+    }
+
+    public function getScripts()
+    {
+        return $this->aliasOf->getScripts();
+    }
+
+    public function setScripts(array $scripts)
+    {
+        $this->aliasOf->setScripts($scripts);
+    }
+
+    public function getRepositories()
+    {
+        return $this->aliasOf->getRepositories();
+    }
+
+    public function setRepositories(array $repositories)
+    {
+        $this->aliasOf->setRepositories($repositories);
+    }
+
+    public function getLicense()
+    {
+        return $this->aliasOf->getLicense();
+    }
+
+    public function setLicense(array $license)
+    {
+        $this->aliasOf->setLicense($license);
+    }
+
+    public function getKeywords()
+    {
+        return $this->aliasOf->getKeywords();
+    }
+
+    public function setKeywords(array $keywords)
+    {
+        $this->aliasOf->setKeywords($keywords);
+    }
+
+    public function getDescription()
+    {
+        return $this->aliasOf->getDescription();
+    }
+
+    public function setDescription($description)
+    {
+        $this->aliasOf->setDescription($description);
+    }
+
+    public function getHomepage()
+    {
+        return $this->aliasOf->getHomepage();
+    }
+
+    public function setHomepage($homepage)
+    {
+        $this->aliasOf->setHomepage($homepage);
+    }
+
+    public function getAuthors()
+    {
+        return $this->aliasOf->getAuthors();
+    }
+
+    public function setAuthors(array $authors)
+    {
+        $this->aliasOf->setAuthors($authors);
+    }
+
+    public function getSupport()
+    {
+        return $this->aliasOf->getSupport();
+    }
+
+    public function setSupport(array $support)
+    {
+        $this->aliasOf->setSupport($support);
+    }
+
+    public function getFunding()
+    {
+        return $this->aliasOf->getFunding();
+    }
+
+    public function setFunding(array $funding)
+    {
+        $this->aliasOf->setFunding($funding);
+    }
+
+    public function isAbandoned()
+    {
+        return $this->aliasOf->isAbandoned();
+    }
+
+    public function getReplacementPackage()
+    {
+        return $this->aliasOf->getReplacementPackage();
+    }
+
+    public function setAbandoned($abandoned)
+    {
+        $this->aliasOf->setAbandoned($abandoned);
+    }
+
+    public function getArchiveName()
+    {
+        return $this->aliasOf->getArchiveName();
+    }
+
+    public function setArchiveName($name)
+    {
+        $this->aliasOf->setArchiveName($name);
+    }
+
+    public function getArchiveExcludes()
+    {
+        return $this->aliasOf->getArchiveExcludes();
+    }
+
+    public function setArchiveExcludes(array $excludes)
+    {
+        $this->aliasOf->setArchiveExcludes($excludes);
+    }
+}

src/Composer/Package/CompletePackage.php

@@ -29,9 +29,11 @@ class CompletePackage extends Package implements CompletePackageInterface
     protected $support = array();
     protected $funding = array();
     protected $abandoned = false;
+    protected $archiveName;
+    protected $archiveExcludes = array();
 
     /**
-     * @param array $scripts
+     * {@inheritDoc}
      */
     public function setScripts(array $scripts)
     {
@@ -47,11 +49,9 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * Set the repositories
+     * {@inheritDoc}
-     *
-     * @param array $repositories
      */
-    public function setRepositories($repositories)
+    public function setRepositories(array $repositories)
     {
         $this->repositories = $repositories;
     }
@@ -65,9 +65,7 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * Set the license
+     * {@inheritDoc}
-     *
-     * @param array $license
      */
     public function setLicense(array $license)
     {
@@ -83,9 +81,7 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * Set the keywords
+     * {@inheritDoc}
-     *
-     * @param array $keywords
      */
     public function setKeywords(array $keywords)
     {
@@ -101,9 +97,7 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * Set the authors
+     * {@inheritDoc}
-     *
-     * @param array $authors
      */
     public function setAuthors(array $authors)
     {
@@ -119,9 +113,7 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * Set the description
+     * {@inheritDoc}
-     *
-     * @param string $description
      */
     public function setDescription($description)
     {
@@ -137,9 +129,7 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * Set the homepage
+     * {@inheritDoc}
-     *
-     * @param string $homepage
      */
     public function setHomepage($homepage)
     {
@@ -155,9 +145,7 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * Set the support information
+     * {@inheritDoc}
-     *
-     * @param array $support
      */
     public function setSupport(array $support)
     {
@@ -173,9 +161,7 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * Set the funding
+     * {@inheritDoc}
-     *
-     * @param array $funding
      */
     public function setFunding(array $funding)
     {
@@ -191,7 +177,7 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * @return bool
+     * {@inheritDoc}
      */
     public function isAbandoned()
     {
@@ -199,7 +185,7 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * @param bool|string $abandoned
+     * {@inheritDoc}
      */
     public function setAbandoned($abandoned)
     {
@@ -207,12 +193,42 @@ class CompletePackage extends Package implements CompletePackageInterface
     }
 
     /**
-     * If the package is abandoned and has a suggested replacement, this method returns it
+     * {@inheritDoc}
-     *
-     * @return string|null
      */
     public function getReplacementPackage()
     {
         return \is_string($this->abandoned) ? $this->abandoned : null;
     }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function setArchiveName($name)
+    {
+        $this->archiveName = $name;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function getArchiveName()
+    {
+        return $this->archiveName;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function setArchiveExcludes(array $excludes)
+    {
+        $this->archiveExcludes = $excludes;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function getArchiveExcludes()
+    {
+        return $this->archiveExcludes;
+    }
 }

src/Composer/Package/CompletePackageInterface.php

@@ -22,19 +22,31 @@ interface CompletePackageInterface extends PackageInterface
     /**
      * Returns the scripts of this package
      *
-     * @return array[] array('script name' => array('listeners'))
+     * @return array<string, string[]> array('script name' => array('listeners'))
-     * @psalm-return array<string, string[]>
      */
     public function getScripts();
 
+    /**
+     * @param array<string, string[]> $scripts
+     * @return void
+     */
+    public function setScripts(array $scripts);
+
     /**
      * Returns an array of repositories
      *
-     * @return array[] Repositories
+     * @return array<array{type: string, url?: string}> Repositories
-     * @psalm-return array<array{type: string, url?: string}>
      */
     public function getRepositories();
 
+    /**
+     * Set the repositories
+     *
+     * @param  array<array{type: string, url?: string}> $repositories
+     * @return void
+     */
+    public function setRepositories(array $repositories);
+
     /**
      * Returns the package license, e.g. MIT, BSD, GPL
      *
@@ -42,6 +54,14 @@ interface CompletePackageInterface extends PackageInterface
      */
     public function getLicense();
 
+    /**
+     * Set the license
+     *
+     * @param  string[] $license
+     * @return void
+     */
+    public function setLicense(array $license);
+
     /**
      * Returns an array of keywords relating to the package
      *
@@ -49,6 +69,14 @@ interface CompletePackageInterface extends PackageInterface
      */
     public function getKeywords();
 
+    /**
+     * Set the keywords
+     *
+     * @param  string[] $keywords
+     * @return void
+     */
+    public function setKeywords(array $keywords);
+
     /**
      * Returns the package description
      *
@@ -56,6 +84,14 @@ interface CompletePackageInterface extends PackageInterface
      */
     public function getDescription();
 
+    /**
+     * Set the description
+     *
+     * @param  string $description
+     * @return void
+     */
+    public function setDescription($description);
+
     /**
      * Returns the package homepage
      *
@@ -63,34 +99,63 @@ interface CompletePackageInterface extends PackageInterface
      */
     public function getHomepage();
 
+    /**
+     * Set the homepage
+     *
+     * @param  string $homepage
+     * @return void
+     */
+    public function setHomepage($homepage);
+
     /**
      * Returns an array of authors of the package
      *
      * Each item can contain name/homepage/email keys
      *
-     * @return array[]
+     * @return array<array{name?: string, homepage?: string, email?: string, role?: string}>
-     * @psalm-return array<array{?name: string, homepage?: string, email?: string, role?: string}>
      */
     public function getAuthors();
 
+    /**
+     * Set the authors
+     *
+     * @param  array<array{name?: string, homepage?: string, email?: string, role?: string}> $authors
+     * @return void
+     */
+    public function setAuthors(array $authors);
+
     /**
      * Returns the support information
      *
-     * @return array
+     * @return array<string, string>
-     * @psalm-return array<string, string>
      */
     public function getSupport();
 
+    /**
+     * Set the support information
+     *
+     * @param  array<string, string> $support
+     * @return void
+     */
+    public function setSupport(array $support);
+
     /**
      * Returns an array of funding options for the package
      *
      * Each item will contain type and url keys
      *
-     * @return array[]
+     * @return array<array{type: string, url: string}>
-     * @psalm-return array<array{type: string, url: string}>
      */
     public function getFunding();
 
+    /**
+     * Set the funding
+     *
+     * @param  array<array{type: string, url: string}> $funding
+     * @return void
+     */
+    public function setFunding(array $funding);
+
     /**
      * Returns if the package is abandoned or not
      *
@@ -101,7 +166,45 @@ interface CompletePackageInterface extends PackageInterface
     /**
      * If the package is abandoned and has a suggested replacement, this method returns it
      *
-     * @return string
+     * @return string|null
      */
     public function getReplacementPackage();
+
+    /**
+     * @param  bool|string $abandoned
+     * @return void
+     */
+    public function setAbandoned($abandoned);
+
+    /**
+     * Returns default base filename for archive
+     *
+     * @return array
+     */
+    public function getArchiveName();
+
+    /**
+     * Sets default base filename for archive
+     *
+     * @param  string $name
+     * @return void
+     */
+    public function setArchiveName($name);
+
+    /**
+     * Returns a list of patterns to exclude from package archives
+     *
+     * @return array
+     */
+    public function getArchiveExcludes();
+
+    /**
+     * Sets a list of patterns to be excluded from archives
+     *
+     * @param  string[] $excludes
+     * @return void
+     */
+    public function setArchiveExcludes(array $excludes);
+
+
 }

src/Composer/Package/Dumper/ArrayDumper.php

@@ -70,13 +70,6 @@ class ArrayDumper
             }
         }
 
-        if ($package->getArchiveName()) {
-            $data['archive']['name'] = $package->getArchiveName();
-        }
-        if ($package->getArchiveExcludes()) {
-            $data['archive']['exclude'] = $package->getArchiveExcludes();
-        }
-
         foreach (BasePackage::$supportedLinkTypes as $type => $opts) {
             if ($links = $package->{'get'.ucfirst($opts['method'])}()) {
                 foreach ($links as $link) {
@@ -102,6 +95,13 @@ class ArrayDumper
         $data = $this->dumpValues($package, $keys, $data);
 
         if ($package instanceof CompletePackageInterface) {
+            if ($package->getArchiveName()) {
+                $data['archive']['name'] = $package->getArchiveName();
+            }
+            if ($package->getArchiveExcludes()) {
+                $data['archive']['exclude'] = $package->getArchiveExcludes();
+            }
+
             $keys = array(
                 'scripts',
                 'license',

src/Composer/Package/Link.php

@@ -26,6 +26,11 @@ class Link
     const TYPE_PROVIDE = 'provides';
     const TYPE_CONFLICT = 'conflicts';
     const TYPE_REPLACE = 'replaces';
+    /**
+     * TODO should be marked private once 5.3 is dropped
+     * @private
+     */
+    const TYPE_UNKNOWN = 'relates to';
 
     /**
      * Will be converted into a constant once the min PHP version allows this
@@ -58,7 +63,7 @@ class Link
 
     /**
      * @var string
-     * @phpstan-var self::TYPE_* $description
+     * @psalm-var self::TYPE_* $description
      */
     protected $description;
 
@@ -73,15 +78,14 @@ class Link
      * @param string              $source
      * @param string              $target
      * @param ConstraintInterface $constraint  Constraint applying to the target of this link
-     * @param string              $description Used to create a descriptive string representation
+     * @param self::TYPE_*        $description Used to create a descriptive string representation
-     * @phpstan-param self::TYPE_* $description
      * @param string|null $prettyConstraint
      */
     public function __construct(
         $source,
         $target,
         ConstraintInterface $constraint,
-        $description = 'relates to',
+        $description = self::TYPE_UNKNOWN,
         $prettyConstraint = null
     ) {
         $this->source = strtolower($source);

src/Composer/Package/Loader/ArrayLoader.php

@@ -12,9 +12,15 @@
 
 namespace Composer\Package\Loader;
 
-use Composer\Package;
 use Composer\Package\AliasPackage;
+use Composer\Package\BasePackage;
+use Composer\Package\CompleteAliasPackage;
+use Composer\Package\CompletePackage;
+use Composer\Package\RootPackage;
+use Composer\Package\PackageInterface;
+use Composer\Package\CompletePackageInterface;
 use Composer\Package\Link;
+use Composer\Package\Package;
 use Composer\Package\RootAliasPackage;
 use Composer\Package\RootPackageInterface;
 use Composer\Package\Version\VersionParser;
@@ -37,11 +43,22 @@ class ArrayLoader implements LoaderInterface
         $this->loadOptions = $loadOptions;
     }
 
+    /**
+     * @template PackageClass of CompletePackageInterface
+     * @param  array                                $config package data
+     * @param  string                               $class  FQCN to be instantiated
+     * @return CompletePackage|CompleteAliasPackage
+     * @phpstan-param class-string<PackageClass> $class
+     */
     public function load(array $config, $class = 'Composer\Package\CompletePackage')
     {
+        if ($class !== 'Composer\Package\CompletePackage' && $class !== 'Composer\Package\RootPackage') {
+            trigger_error('The $class arg is deprecated, please reach out to Composer maintainers ASAP if you still need this.', E_USER_DEPRECATED);
+        }
+
         $package = $this->createObject($config, $class);
 
-        foreach (Package\BasePackage::$supportedLinkTypes as $type => $opts) {
+        foreach (BasePackage::$supportedLinkTypes as $type => $opts) {
             if (isset($config[$type])) {
                 $method = 'set'.ucfirst($opts['method']);
                 $package->{$method}(
@@ -60,8 +77,19 @@ class ArrayLoader implements LoaderInterface
         return $package;
     }
 
-    public function loadPackages(array $versions, $class)
+    /**
+     * @template PackageClass of CompletePackageInterface
+     * @param  array                                      $versions
+     * @param  string                                      $class    FQCN to be instantiated
+     * @return list<CompletePackage|CompleteAliasPackage>
+     * @phpstan-param class-string<PackageClass> $class
+     */
+    public function loadPackages(array $versions, $class = 'Composer\Package\CompletePackage')
     {
+        if ($class !== 'Composer\Package\CompletePackage') {
+            trigger_error('The $class arg is deprecated, please reach out to Composer maintainers ASAP if you still need this.', E_USER_DEPRECATED);
+        }
+
         $packages = array();
         $linkCache = array();
 
@@ -77,6 +105,13 @@ class ArrayLoader implements LoaderInterface
         return $packages;
     }
 
+    /**
+     * @template PackageClass of CompletePackageInterface
+     * @param  array                       $config package data
+     * @param  string                      $class  FQCN to be instantiated
+     * @return CompletePackage|RootPackage
+     * @phpstan-param class-string<PackageClass> $class
+     */
     private function createObject(array $config, $class)
     {
         if (!isset($config['name'])) {
@@ -101,8 +136,17 @@ class ArrayLoader implements LoaderInterface
         return new $class($config['name'], $version, $config['version']);
     }
 
-    private function configureObject($package, array $config)
+    /**
+     * @param  CompletePackageInterface                                          $package
+     * @param  array                                                             $config  package data
+     * @return RootPackage|RootAliasPackage|CompletePackage|CompleteAliasPackage
+     */
+    private function configureObject(PackageInterface $package, array $config)
     {
+        if (!$package instanceof Package) {
+            throw new \LogicException('ArrayLoader expects instances of the Composer\Package\Package class to function correctly');
+        }
+
         $package->setType(isset($config['type']) ? strtolower($config['type']) : 'library');
 
         if (isset($config['target-dir'])) {
@@ -200,6 +244,7 @@ class ArrayLoader implements LoaderInterface
             $package->setNotificationUrl($config['notification-url']);
         }
 
+        if ($package instanceof CompletePackageInterface) {
             if (!empty($config['archive']['name'])) {
                 $package->setArchiveName($config['archive']['name']);
             }
@@ -207,7 +252,6 @@ class ArrayLoader implements LoaderInterface
                 $package->setArchiveExcludes($config['archive']['exclude']);
             }
 
-        if ($package instanceof Package\CompletePackageInterface) {
             if (isset($config['scripts']) && \is_array($config['scripts'])) {
                 foreach ($config['scripts'] as $event => $listeners) {
                     $config['scripts'][$event] = (array) $listeners;
@@ -262,18 +306,28 @@ class ArrayLoader implements LoaderInterface
                 return new RootAliasPackage($package, $aliasNormalized, $prettyAlias);
             }
 
+            if ($package instanceof CompletePackageInterface) {
+                return new CompleteAliasPackage($package, $aliasNormalized, $prettyAlias);
+            }
+
             return new AliasPackage($package, $aliasNormalized, $prettyAlias);
         }
 
         return $package;
     }
 
+    /**
+     * @param  array            $linkCache
+     * @param  PackageInterface $package
+     * @param  array            $config
+     * @return void
+     */
     private function configureCachedLinks(&$linkCache, $package, array $config)
     {
         $name = $package->getName();
         $prettyVersion = $package->getPrettyVersion();
 
-        foreach (Package\BasePackage::$supportedLinkTypes as $type => $opts) {
+        foreach (BasePackage::$supportedLinkTypes as $type => $opts) {
             if (isset($config[$type])) {
                 $method = 'set'.ucfirst($opts['method']);
 
@@ -300,8 +354,7 @@ class ArrayLoader implements LoaderInterface
     /**
      * @param  string       $source        source package name
      * @param  string       $sourceVersion source package version (pretty version ideally)
-     * @param string $description   link description (e.g. requires, replaces, ..)
+     * @param  Link::TYPE_* $description   link description (e.g. requires, replaces, ..)
-     * @phpstan-param Link::TYPE_* $description
      * @param  array        $links         array of package name => constraint mappings
      * @return Link[]
      */
@@ -315,6 +368,14 @@ class ArrayLoader implements LoaderInterface
         return $res;
     }
 
+    /**
+     * @param  string       $source           source package name
+     * @param  string       $sourceVersion    source package version (pretty version ideally)
+     * @param  Link::TYPE_* $description      link description (e.g. requires, replaces, ..)
+     * @param  string       $target           target package name
+     * @param  string       $prettyConstraint constraint string
+     * @return Link
+     */
     private function createLink($source, $sourceVersion, $description, $target, $prettyConstraint)
     {
         if (!\is_string($prettyConstraint)) {
@@ -338,7 +399,7 @@ class ArrayLoader implements LoaderInterface
     public function getBranchAlias(array $config)
     {
         if (strpos($config['version'], 'dev-') !== 0 && '-dev' !== substr($config['version'], -4)) {
-            return;
+            return null;
         }
 
         if (isset($config['extra']['branch-alias']) && \is_array($config['extra']['branch-alias'])) {
@@ -382,5 +443,7 @@ class ArrayLoader implements LoaderInterface
         ) {
             return VersionParser::DEFAULT_BRANCH_ALIAS;
         }
+
+        return null;
     }
 }

src/Composer/Package/Loader/JsonLoader.php

@@ -13,6 +13,8 @@
 namespace Composer\Package\Loader;
 
 use Composer\Json\JsonFile;
+use Composer\Package\CompletePackage;
+use Composer\Package\CompleteAliasPackage;
 
 /**
  * @author Konstantin Kudryashiv <ever.zet@gmail.com>
@@ -28,7 +30,7 @@ class JsonLoader
 
     /**
      * @param  string|JsonFile                      $json A filename, json string or JsonFile instance to load the package from
-     * @return \Composer\Package\PackageInterface
+     * @return CompletePackage|CompleteAliasPackage
      */
     public function load($json)
     {

src/Composer/Package/Loader/RootPackageLoader.php

@@ -16,7 +16,9 @@ use Composer\Package\BasePackage;
 use Composer\Package\AliasPackage;
 use Composer\Config;
 use Composer\IO\IOInterface;
+use Composer\Package\Package;
 use Composer\Package\RootPackageInterface;
+use Composer\Package\RootAliasPackage;
 use Composer\Repository\RepositoryFactory;
 use Composer\Package\Version\VersionGuesser;
 use Composer\Package\Version\VersionParser;
@@ -58,13 +60,18 @@ class RootPackageLoader extends ArrayLoader
     }
 
     /**
+     * @template PackageClass of RootPackage
      * @param  array                        $config package data
-     * @param  string               $class  FQCN to be instantiated
+     * @param  class-string<PackageClass>   $class  FQCN to be instantiated
      * @param  string                       $cwd    cwd of the root package to be used to guess the version if it is not provided
-     * @return RootPackageInterface
+     * @return RootPackage|RootAliasPackage
      */
     public function load(array $config, $class = 'Composer\Package\RootPackage', $cwd = null)
     {
+        if ($class !== 'Composer\Package\RootPackage') {
+            trigger_error('The $class arg is deprecated, please reach out to Composer maintainers ASAP if you still need this.', E_USER_DEPRECATED);
+        }
+
         if (!isset($config['name'])) {
             $config['name'] = '__root__';
         } elseif ($err = ValidatingArrayLoader::hasPackageNamingError($config['name'])) {
@@ -105,9 +112,16 @@ class RootPackageLoader extends ArrayLoader
             }
         }
 
-        $realPackage = $package = parent::load($config, $class);
+        /** @var RootPackage|RootAliasPackage $package */
-        if ($realPackage instanceof AliasPackage) {
+        $package = parent::load($config, $class);
+        if ($package instanceof RootAliasPackage) {
             $realPackage = $package->getAliasOf();
+        } else {
+            $realPackage = $package;
+        }
+
+        if (!$realPackage instanceof RootPackage) {
+            throw new \LogicException('Expecting a Composer\Package\RootPackage at this point');
         }
 
         if ($autoVersioned) {

src/Composer/Package/Locker.php

@@ -186,7 +186,11 @@ class Locker
             if (isset($lockData['aliases'])) {
                 foreach ($lockData['aliases'] as $alias) {
                     if (isset($packageByName[$alias['package']])) {
+                        if ($packageByName[$alias['package']] instanceof CompletePackageInterface) {
+                            $aliasPkg = new CompleteAliasPackage($packageByName[$alias['package']], $alias['alias_normalized'], $alias['alias']);
+                        } else {
                             $aliasPkg = new AliasPackage($packageByName[$alias['package']], $alias['alias_normalized'], $alias['alias']);
+                        }
                         $aliasPkg->setRootPackageAlias(true);
                         $packages->addPackage($aliasPkg);
                     }

src/Composer/Package/Package.php

@@ -57,9 +57,9 @@ class Package extends BasePackage
     protected $autoload = array();
     protected $devAutoload = array();
     protected $includePaths = array();
-    protected $archiveName;
-    protected $archiveExcludes = array();
     protected $isDefaultBranch = false;
+    /** @var array */
+    protected $transportOptions = array();
 
     /**
      * Creates a new in memory package.
@@ -125,7 +125,7 @@ class Package extends BasePackage
     public function getTargetDir()
     {
         if (null === $this->targetDir) {
-            return;
+            return null;
         }
 
         return ltrim(preg_replace('{ (?:^|[\\\\/]+) \.\.? (?:[\\\\/]+|$) (?:\.\.? (?:[\\\\/]+|$) )*}x', '/', $this->targetDir), '/');
@@ -228,7 +228,7 @@ class Package extends BasePackage
     }
 
     /**
-     * @param array|null $mirrors
+     * {@inheritDoc}
      */
     public function setSourceMirrors($mirrors)
     {
@@ -316,7 +316,7 @@ class Package extends BasePackage
     }
 
     /**
-     * @param array|null $mirrors
+     * {@inheritDoc}
      */
     public function setDistMirrors($mirrors)
     {
@@ -339,6 +339,22 @@ class Package extends BasePackage
         return $this->getUrls($this->distUrl, $this->distMirrors, $this->distReference, $this->distType, 'dist');
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    public function getTransportOptions()
+    {
+        return $this->transportOptions;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function setTransportOptions(array $options)
+    {
+        $this->transportOptions = $options;
+    }
+
     /**
      * {@inheritDoc}
      */
@@ -553,42 +569,6 @@ class Package extends BasePackage
         return $this->notificationUrl;
     }
 
-    /**
-     * Sets default base filename for archive
-     *
-     * @param string $name
-     */
-    public function setArchiveName($name)
-    {
-        $this->archiveName = $name;
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public function getArchiveName()
-    {
-        return $this->archiveName;
-    }
-
-    /**
-     * Sets a list of patterns to be excluded from archives
-     *
-     * @param array $excludes
-     */
-    public function setArchiveExcludes(array $excludes)
-    {
-        $this->archiveExcludes = $excludes;
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public function getArchiveExcludes()
-    {
-        return $this->archiveExcludes;
-    }
-
     /**
      * @param bool $defaultBranch
      */

src/Composer/Package/PackageInterface.php

@@ -142,6 +142,12 @@ interface PackageInterface
      */
     public function getSourceMirrors();
 
+    /**
+     * @param  array|null $mirrors
+     * @return void
+     */
+    public function setSourceMirrors($mirrors);
+
     /**
      * Returns the type of the distribution archive of this version, e.g. zip, tarball
      *
@@ -184,6 +190,12 @@ interface PackageInterface
      */
     public function getDistMirrors();
 
+    /**
+     * @param  array|null $mirrors
+     * @return void
+     */
+    public function setDistMirrors($mirrors);
+
     /**
      * Returns the version of this package
      *
@@ -357,20 +369,6 @@ interface PackageInterface
      */
     public function getPrettyString();
 
-    /**
-     * Returns default base filename for archive
-     *
-     * @return array
-     */
-    public function getArchiveName();
-
-    /**
-     * Returns a list of patterns to exclude from package archives
-     *
-     * @return array
-     */
-    public function getArchiveExcludes();
-
     /**
      * @return bool
      */
@@ -383,6 +381,13 @@ interface PackageInterface
      */
     public function getTransportOptions();
 
+    /**
+     * Configures the list of options to download package dist files
+     *
+     * @return void
+     */
+    public function setTransportOptions(array $options);
+
     /**
      * @param string $reference
      *

src/Composer/Package/RootAliasPackage.php

@@ -15,13 +15,31 @@ namespace Composer\Package;
 /**
  * @author Jordi Boggiano <j.boggiano@seld.be>
  */
-class RootAliasPackage extends AliasPackage implements RootPackageInterface
+class RootAliasPackage extends CompleteAliasPackage implements RootPackageInterface
 {
+    /** @var RootPackageInterface */
+    protected $aliasOf;
+
+    /**
+     * All descendants' constructors should call this parent constructor
+     *
+     * @param RootPackageInterface $aliasOf       The package this package is an alias of
+     * @param string                   $version       The version the alias must report
+     * @param string                   $prettyVersion The alias's non-normalized version
+     */
     public function __construct(RootPackageInterface $aliasOf, $version, $prettyVersion)
     {
         parent::__construct($aliasOf, $version, $prettyVersion);
     }
 
+    /**
+     * @return RootPackageInterface
+     */
+    public function getAliasOf()
+    {
+        return $this->aliasOf;
+    }
+
     /**
      * {@inheritDoc}
      */
@@ -117,14 +135,6 @@ class RootAliasPackage extends AliasPackage implements RootPackageInterface
         $this->aliasOf->setReplaces($replaces);
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public function setRepositories($repositories)
-    {
-        $this->aliasOf->setRepositories($repositories);
-    }
-
     /**
      * {@inheritDoc}
      */

src/Composer/Package/RootPackageInterface.php

@@ -105,7 +105,7 @@ interface RootPackageInterface extends CompletePackageInterface
      *
      * @param array $repositories
      */
-    public function setRepositories($repositories);
+    public function setRepositories(array $repositories);
 
     /**
      * Set the autoload mapping

src/Composer/Plugin/PluginManager.php

@@ -462,15 +462,20 @@ class PluginManager
         ) {
             throw new \UnexpectedValueException('Plugin '.get_class($plugin).' provided invalid capability class name(s), got '.var_export($capabilities[$capability], 1));
         }
+
+        return null;
     }
 
     /**
+     * @template CapabilityClass of Capability
      * @param  PluginInterface $plugin
-     * @param  string          $capabilityClassName The fully qualified name of the API interface which the plugin may provide
+     * @param  class-string<CapabilityClass> $capabilityClassName The fully qualified name of the API interface which the plugin may provide
      *                                                            an implementation of.
      * @param  array                         $ctorArgs            Arguments passed to Capability's constructor.
      *                                                            Keeping it an array will allow future values to be passed w\o changing the signature.
      * @return null|Capability
+     * @phpstan-param class-string<CapabilityClass> $capabilityClassName
+     * @phpstan-return null|CapabilityClass
      */
     public function getPluginCapability(PluginInterface $plugin, $capabilityClassName, array $ctorArgs = array())
     {
@@ -491,14 +496,17 @@ class PluginManager
 
             return $capabilityObj;
         }
+
+        return null;
     }
 
      /**
-     * @param  string       $capabilityClassName The fully qualified name of the API interface which the plugin may provide
+     * @template CapabilityClass of Capability
+     * @param  class-string<CapabilityClass> $capabilityClassName The fully qualified name of the API interface which the plugin may provide
      *                                                         an implementation of.
      * @param  array                      $ctorArgs            Arguments passed to Capability's constructor.
      *                                                         Keeping it an array will allow future values to be passed w\o changing the signature.
-     * @return Capability[]
+     * @return CapabilityClass[]
      */
     public function getPluginCapabilities($capabilityClassName, array $ctorArgs = array())
     {

src/Composer/Repository/ArrayRepository.php

@@ -13,6 +13,7 @@
 namespace Composer\Repository;
 
 use Composer\Package\AliasPackage;
+use Composer\Package\CompleteAliasPackage;
 use Composer\Package\PackageInterface;
 use Composer\Package\CompletePackageInterface;
 use Composer\Package\Version\VersionParser;
@@ -27,13 +28,13 @@ use Composer\Semver\Constraint\Constraint;
  */
 class ArrayRepository implements RepositoryInterface
 {
-    /** @var PackageInterface[] */
+    /** @var ?PackageInterface[] */
-    protected $packages;
+    protected $packages = null;
 
     /**
-     * @var PackageInterface[] indexed by package unique name and used to cache hasPackage calls
+     * @var ?PackageInterface[] indexed by package unique name and used to cache hasPackage calls
      */
-    protected $packageMap;
+    protected $packageMap = null;
 
     public function __construct(array $packages = array())
     {
@@ -220,7 +221,7 @@ class ArrayRepository implements RepositoryInterface
                 if ($packageName === $link->getTarget()) {
                     $result[$candidate->getName()] = array(
                         'name' => $candidate->getName(),
-                        'description' => $candidate->getDescription(),
+                        'description' => $candidate instanceof CompletePackageInterface ? $candidate->getDescription() : null,
                         'type' => $candidate->getType(),
                     );
                     continue 2;
@@ -233,7 +234,15 @@ class ArrayRepository implements RepositoryInterface
 
     protected function createAliasPackage(PackageInterface $package, $alias, $prettyAlias)
     {
-        return new AliasPackage($package instanceof AliasPackage ? $package->getAliasOf() : $package, $alias, $prettyAlias);
+        while ($package instanceof AliasPackage) {
+            $package = $package->getAliasOf();
+        }
+
+        if ($package instanceof CompletePackageInterface) {
+            return new CompleteAliasPackage($package, $alias, $prettyAlias);
+        }
+
+        return new AliasPackage($package, $alias, $prettyAlias);
     }
 
     /**

src/Composer/Repository/ComposerRepository.php

@@ -16,6 +16,8 @@ use Composer\Package\BasePackage;
 use Composer\Package\Loader\ArrayLoader;
 use Composer\Package\PackageInterface;
 use Composer\Package\AliasPackage;
+use Composer\Package\CompletePackage;
+use Composer\Package\CompleteAliasPackage;
 use Composer\Package\Version\VersionParser;
 use Composer\Package\Version\StabilityFilter;
 use Composer\Json\JsonFile;
@@ -167,7 +169,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
             }
 
             if ($this->hasAvailablePackageList && !$this->lazyProvidersRepoContains($name)) {
-                return;
+                return null;
             }
 
             $packages = $this->loadAsyncPackages(array($name => $constraint));
@@ -182,7 +184,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
                 }
             }
 
-            return;
+            return null;
         }
 
         return parent::findPackage($name, $constraint);
@@ -428,7 +430,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
             foreach ($search['results'] as $result) {
                 // do not show virtual packages in results as they are not directly useful from a composer perspective
                 if (empty($result['virtual'])) {
-                    $results[] = $result;
+                    $results[] = array('name' => $result['name'], 'description' => $result['description']);
                 }
             }
 
@@ -441,7 +443,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
 
             foreach ($this->getPackageNames() as $name) {
                 if (preg_match($regex, $name)) {
-                    $results[] = array('name' => $name);
+                    $results[] = array('name' => $name, 'description' => '');
                 }
             }
 
@@ -1039,6 +1041,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
      * TODO v3 should make this private once we can drop PHP 5.3 support
      *
      * @private
+     * @return list<CompletePackage|CompleteAliasPackage>
      */
     public function createPackages(array $packages, $source = null)
     {
@@ -1053,7 +1056,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
                 }
             }
 
-            $packageInstances = $this->loader->loadPackages($packages, 'Composer\Package\CompletePackage');
+            $packageInstances = $this->loader->loadPackages($packages);
 
             foreach ($packageInstances as $package) {
                 if (isset($this->sourceMirrors[$package->getSourceType()])) {

src/Composer/Repository/FilterRepository.php

@@ -165,9 +165,9 @@ class FilterRepository implements RepositoryInterface
     public function getProviders($packageName)
     {
         $result = array();
-        foreach ($this->repo->getProviders($packageName) as $provider) {
+        foreach ($this->repo->getProviders($packageName) as $name => $provider) {
             if ($this->isAllowed($provider['name'])) {
-                $result[] = $provider;
+                $result[$name] = $provider;
             }
         }
 

src/Composer/Repository/PlatformRepository.php

@@ -14,6 +14,7 @@ namespace Composer\Repository;
 
 use Composer\Composer;
 use Composer\Package\CompletePackage;
+use Composer\Package\CompletePackageInterface;
 use Composer\Package\Link;
 use Composer\Package\PackageInterface;
 use Composer\Package\Version\VersionParser;
@@ -491,7 +492,9 @@ class PlatformRepository extends ArrayRepository
             } else {
                 $actualText = 'actual: '.$package->getPrettyVersion();
             }
+            if ($overrider instanceof CompletePackageInterface) {
                 $overrider->setDescription($overrider->getDescription().', '.$actualText);
+            }
 
             return;
         }
@@ -512,6 +515,9 @@ class PlatformRepository extends ArrayRepository
         parent::addPackage($package);
     }
 
+    /**
+     * @return CompletePackage
+     */
     private function addOverriddenPackage(array $override, $name = null)
     {
         $version = $this->versionParser->normalize($override['version']);

src/Composer/Repository/RepositoryInterface.php

@@ -71,15 +71,11 @@ interface RepositoryInterface extends \Countable
      * - The namesFound returned are names which should be considered as canonically found in this repository, that should not be looked up in any further lower priority repositories
      *
      * @param ConstraintInterface[]                          $packageNameMap        package names pointing to constraints
-     * @param int[]                 $acceptableStabilities array of stability => BasePackage::STABILITY_* value
+     * @param array<string, BasePackage::STABILITY_*>        $acceptableStabilities array of stability => BasePackage::STABILITY_* value
-     * @psalm-param array<string, BasePackage::STABILITY_*> $acceptableStabilities
+     * @param array<string, BasePackage::STABILITY_*>        $stabilityFlags  an array of package name => BasePackage::STABILITY_* value
-     * @param int[] $stabilityFlags an array of package name => BasePackage::STABILITY_* value
+     * @param array<string, array<string, PackageInterface>> $alreadyLoaded an array of package name => package version => package
-     * @psalm-param array<string, BasePackage::STABILITY_*> $stabilityFlags
-     * @param array[] $alreadyLoaded an array of package name => package version => package
-     * @psalm-param array<string, array<string, PackageInterface>> $alreadyLoaded
      *
-     * @return array [namesFound => string[], packages => PackageInterface[]]
+     * @return array{namesFound: string[], packages: PackageInterface[]}
-     * @psalm-return array{namesFound: string[], packages: PackageInterface[]}
      */
     public function loadPackages(array $packageNameMap, array $acceptableStabilities, array $stabilityFlags, array $alreadyLoaded = array());
 

src/Composer/Repository/RepositorySet.php

@@ -20,6 +20,8 @@ use Composer\IO\IOInterface;
 use Composer\IO\NullIO;
 use Composer\Package\BasePackage;
 use Composer\Package\AliasPackage;
+use Composer\Package\CompleteAliasPackage;
+use Composer\Package\CompletePackageInterface;
 use Composer\Semver\Constraint\ConstraintInterface;
 use Composer\Package\Version\StabilityFilter;
 
@@ -252,7 +254,11 @@ class RepositorySet
                     while ($package instanceof AliasPackage) {
                         $package = $package->getAliasOf();
                     }
+                    if ($package instanceof CompletePackageInterface) {
+                        $aliasPackage = new CompleteAliasPackage($package, $alias['alias_normalized'], $alias['alias']);
+                    } else {
                         $aliasPackage = new AliasPackage($package, $alias['alias_normalized'], $alias['alias']);
+                    }
                     $aliasPackage->setRootPackageAlias(true);
                     $packages[] = $aliasPackage;
                 }

src/Composer/Repository/Vcs/BitbucketDriver.php

@@ -33,9 +33,9 @@ abstract class BitbucketDriver extends VcsDriver
     protected $cloneHttpsUrl = '';
 
     /**
-     * @var VcsDriver
+     * @var ?VcsDriver
      */
-    protected $fallbackDriver;
+    protected $fallbackDriver = null;
     /** @var string|null if set either git or hg */
     protected $vcsType;
 

src/Composer/Repository/Vcs/GitBitbucketDriver.php

@@ -31,6 +31,10 @@ class GitBitbucketDriver extends BitbucketDriver
 
         if (null === $this->rootIdentifier) {
             if (!$this->getRepoData()) {
+                if (!$this->fallbackDriver) {
+                    throw new \LogicException('A fallback driver should be setup if getRepoData returns false');
+                }
+
                 return $this->fallbackDriver->getRootIdentifier();
             }
 

src/Composer/Repository/Vcs/GitHubDriver.php

@@ -39,9 +39,9 @@ class GitHubDriver extends VcsDriver
     /**
      * Git Driver
      *
-     * @var GitDriver
+     * @var ?GitDriver
      */
-    protected $gitDriver;
+    protected $gitDriver = null;
 
     /**
      * {@inheritDoc}

src/Composer/Repository/Vcs/GitLabDriver.php

@@ -56,9 +56,9 @@ class GitLabDriver extends VcsDriver
     /**
      * Git Driver
      *
-     * @var GitDriver
+     * @var ?GitDriver
      */
-    protected $gitDriver;
+    protected $gitDriver = null;
 
     /**
      * Defaults to true unless we can make sure it is public

src/Composer/Repository/Vcs/HgBitbucketDriver.php

@@ -31,6 +31,10 @@ class HgBitbucketDriver extends BitbucketDriver
 
         if (null === $this->rootIdentifier) {
             if (!$this->getRepoData()) {
+                if (!$this->fallbackDriver) {
+                    throw new \LogicException('A fallback driver should be setup if getRepoData returns false');
+                }
+
                 return $this->fallbackDriver->getRootIdentifier();
             }
 

src/Composer/Repository/Vcs/HgDriver.php

@@ -125,7 +125,7 @@ class HgDriver extends VcsDriver
         $this->process->execute($resource, $content, $this->repoDir);
 
         if (!trim($content)) {
-            return;
+            return null;
         }
 
         return $content;

src/Composer/Repository/Vcs/PerforceDriver.php

@@ -25,8 +25,8 @@ class PerforceDriver extends VcsDriver
 {
     protected $depot;
     protected $branch;
-    /** @var Perforce */
+    /** @var ?Perforce */
-    protected $perforce;
+    protected $perforce = null;
 
     /**
      * {@inheritDoc}
@@ -147,7 +147,7 @@ class PerforceDriver extends VcsDriver
      */
     public function getContents($url)
     {
-        return false;
+        throw new \BadMethodCallException('Not implemented/used in PerforceDriver');
     }
 
     /**

src/Composer/Util/AuthHelper.php

@@ -154,7 +154,7 @@ class AuthHelper
         } else {
             // 404s are only handled for github
             if ($statusCode === 404) {
-                return;
+                return null;
             }
 
             // fail if the console is not interactive

src/Composer/Util/Bitbucket.php

@@ -30,8 +30,8 @@ class Bitbucket
     private $process;
     /** @var HttpDownloader */
     private $httpDownloader;
-    /** @var array */
+    /** @var array{access_token: string, expires_in?: int}|null */
-    private $token = array();
+    private $token = null;
     /** @var int|null */
     private $time;
 
@@ -191,7 +191,7 @@ class Bitbucket
      */
     public function requestToken($originUrl, $consumerKey, $consumerSecret)
     {
-        if (!empty($this->token) || $this->getTokenFromConfig($originUrl)) {
+        if ($this->token !== null || $this->getTokenFromConfig($originUrl)) {
             return $this->token['access_token'];
         }
 
@@ -202,6 +202,10 @@ class Bitbucket
 
         $this->storeInAuthConfig($originUrl, $consumerKey, $consumerSecret);
 
+        if (!isset($this->token['expires_in']) || !isset($this->token['access_token'])) {
+            throw new \LogicException('Expected a token configured with expires_in and access_token present, got '.json_encode($this->token));
+        }
+
         return $this->token['access_token'];
     }
 
@@ -215,6 +219,10 @@ class Bitbucket
     {
         $this->config->getConfigSource()->removeConfigSetting('bitbucket-oauth.'.$originUrl);
 
+        if (!isset($this->token['expires_in']) || !isset($this->token['access_token'])) {
+            throw new \LogicException('Expected a token configured with expires_in and access_token present, got '.json_encode($this->token));
+        }
+
         $time = null === $this->time ? time() : $this->time;
         $consumer = array(
             "consumer-key" => $consumerKey,

src/Composer/Util/ErrorHandler.php

@@ -39,7 +39,7 @@ class ErrorHandler
     {
         // error code is not included in error_reporting
         if (!(error_reporting() & $level)) {
-            return;
+            return true;
         }
 
         if (filter_var(ini_get('xdebug.scream'), FILTER_VALIDATE_BOOLEAN)) {

src/Composer/Util/Filesystem.php

@@ -12,7 +12,7 @@
 
 namespace Composer\Util;
 
-use React\Promise\Promise;
+use React\Promise\PromiseInterface;
 use RecursiveDirectoryIterator;
 use RecursiveIteratorIterator;
 use Symfony\Component\Filesystem\Exception\IOException;
@@ -128,7 +128,7 @@ class Filesystem
      *
      * @param  string            $directory
      * @throws \RuntimeException
-     * @return Promise
+     * @return PromiseInterface
      */
     public function removeDirectoryAsync($directory)
     {
@@ -569,7 +569,7 @@ class Filesystem
      * And other possible unforeseen disasters, see https://github.com/composer/composer/pull/9422
      *
      * @param  string $path
-     * @return bool
+     * @return string
      */
     public static function trimTrailingSlash($path)
     {

src/Composer/Util/Http/ProxyHelper.php

@@ -116,6 +116,8 @@ class ProxyHelper
                 return $_SERVER[$name];
             }
         }
+
+        return null;
     }
 
     /**

src/Composer/Util/Http/ProxyManager.php

@@ -29,11 +29,11 @@ class ProxyManager
     private $hasProxy;
     private $info;
     private $lastProxy;
-    /** @var NoProxyPattern */
+    /** @var ?NoProxyPattern */
-    private $noProxyHandler;
+    private $noProxyHandler = null;
 
-    /** @var ProxyManager */
+    /** @var ?ProxyManager */
-    private static $instance;
+    private static $instance = null;
 
     private function __construct()
     {
@@ -145,7 +145,7 @@ class ProxyManager
         if ($this->hasProxy) {
             $this->info = implode(', ', $info);
             if ($noProxy) {
-                $this->noProxyHandler = array(new NoProxyPattern($noProxy), 'test');
+                $this->noProxyHandler = new NoProxyPattern($noProxy);
             }
         }
     }
@@ -176,7 +176,7 @@ class ProxyManager
     private function noProxy($requestUrl)
     {
         if ($this->noProxyHandler) {
-            if (call_user_func($this->noProxyHandler, $requestUrl)) {
+            if ($this->noProxyHandler->test($requestUrl)) {
                 $this->lastProxy = 'excluded by no_proxy';
 
                 return true;

src/Composer/Util/NoProxyPattern.php

@@ -25,7 +25,7 @@ class NoProxyPattern
     protected $hostNames = array();
 
     /**
-     * @var object[]
+     * @var (null|object)[]
      */
     protected $rules = array();
 
@@ -74,7 +74,7 @@ class NoProxyPattern
      *
      * @param string $url
      *
-     * @return bool|stdclass
+     * @return bool|stdClass
      */
     protected function getUrlData($url)
     {
@@ -110,7 +110,7 @@ class NoProxyPattern
      *
      * @param int      $index
      * @param string   $hostName
-     * @param string $url
+     * @param stdClass $url
      *
      * @return bool
      */
@@ -198,7 +198,7 @@ class NoProxyPattern
      * Creates an object containing IP data if the host is an IP address
      *
      * @param string        $host
-     * @param null|stdclass $ipdata      Set by method if IP address found
+     * @param null|stdClass $ipdata      Set by method if IP address found
      * @param bool          $allowPrefix Whether a CIDR prefix-length is expected
      *
      * @return bool False if the host contains invalid data
@@ -334,9 +334,9 @@ class NoProxyPattern
      *
      * @param string        $host
      * @param int           $port
-     * @param null|stdclass $ipdata
+     * @param null|stdClass $ipdata
      *
-     * @return stdclass
+     * @return stdClass
      */
     private function makeData($host, $port, $ipdata)
     {
@@ -355,7 +355,7 @@ class NoProxyPattern
      * @param int         $size    Byte size of in_addr
      * @param null|string $netmask Network mask
      *
-     * @return stdclass
+     * @return stdClass
      */
     private function makeIpData($ip, $size, $netmask)
     {

src/Composer/Util/PackageSorter.php

@@ -22,15 +22,15 @@ class PackageSorter
      *
      * Packages of equal weight retain the original order
      *
-     * @param  array $packages
+     * @param  PackageInterface[] $packages
-     * @return array
+     * @return PackageInterface[] sorted array
      */
     public static function sortPackages(array $packages)
     {
         $usageList = array();
 
-        foreach ($packages as $package) { /** @var PackageInterface $package */
+        foreach ($packages as $package) {
-            foreach (array_merge($package->getRequires(), $package->getDevRequires()) as $link) { /** @var Link $link */
+            foreach (array_merge($package->getRequires(), $package->getDevRequires()) as $link) {
                 $target = $link->getTarget();
                 $usageList[$target][] = $package->getName();
             }

src/Composer/Util/ProcessExecutor.php

@@ -17,6 +17,7 @@ use Symfony\Component\Process\Process;
 use Symfony\Component\Process\ProcessUtils;
 use Symfony\Component\Process\Exception\RuntimeException;
 use React\Promise\Promise;
+use React\Promise\PromiseInterface;
 
 /**
  * @author Robert Schönthal <seroscho@googlemail.com>
@@ -142,7 +143,7 @@ class ProcessExecutor
      *
      * @param  string           $command the command to execute
      * @param  string           $cwd     the working directory
-     * @return Promise
+     * @return PromiseInterface
      */
     public function executeAsync($command, $cwd = null)
     {

src/Composer/Util/RemoteFilesystem.php

@@ -302,7 +302,7 @@ class RemoteFilesystem
                 $e->setStatusCode(self::findStatusCode($http_response_header));
                 try {
                     $e->setResponse($this->decodeResult($result, $http_response_header));
-                } catch (\Exception $e) {
+                } catch (\Exception $discarded) {
                     $e->setResponse($result);
                 }
 

src/Composer/Util/StreamContextFactory.php

@@ -30,7 +30,7 @@ final class StreamContextFactory
      * Creates a context supporting HTTP proxies
      *
      * @param string $url URL the context is to be used for
-     * @psalm-param array{http: array{follow_location?: int, max_redirects?: int, header?: string|array<string, string|int>}} $defaultOptions
+     * @psalm-param array{http?: array{follow_location?: int, max_redirects?: int, header?: string|array<string, string|int>}} $defaultOptions
      * @param  array             $defaultOptions Options to merge with the default
      * @param  array             $defaultParams  Parameters to specify on the context
      * @throws \RuntimeException if https proxy required and OpenSSL uninstalled

src/Composer/Util/SyncHelper.php

@@ -41,7 +41,7 @@ class SyncHelper
             if ($type === 'update') {
                 self::await($loop, $downloader->update($package, $path, $prevPackage));
             } else {
-                self::await($loop, $downloader->install($package, $path, $prevPackage));
+                self::await($loop, $downloader->install($package, $path));
             }
         } catch (\Exception $e) {
             self::await($loop, $downloader->cleanup($type, $package, $path, $prevPackage));

tests/Composer/Test/Downloader/PerforceDownloaderTest.php

@@ -26,7 +26,7 @@ use Composer\Util\Filesystem;
 class PerforceDownloaderTest extends TestCase
 {
     protected $config;
-    /** @var PerforceDownloader */
+    /** @var ?PerforceDownloader */
     protected $downloader;
     protected $io;
     protected $package;

tests/Composer/Test/Downloader/ZipDownloaderTest.php

@@ -386,12 +386,12 @@ class MockedZipDownloader extends ZipDownloader
 {
     public function download(PackageInterface $package, $path, PackageInterface $prevPackage = null, $output = true)
     {
-        return;
+        return \React\Promise\resolve();
     }
 
     public function install(PackageInterface $package, $path, $output = true)
     {
-        return;
+        return \React\Promise\resolve();
     }
 
     public function extract(PackageInterface $package, $file, $path)

tests/Composer/Test/InstallerTest.php

@@ -378,6 +378,7 @@ class InstallerTest extends TestCase
             $this->assertSame($expectInstalled, $actualInstalled);
         }
 
+        /** @var InstallationManagerMock $installationManager */
         $installationManager = $composer->getInstallationManager();
         $this->assertSame(rtrim($expect), implode("\n", $installationManager->getTrace()));
 

tests/Composer/Test/Mock/InstallationManagerMock.php

@@ -34,7 +34,7 @@ class InstallationManagerMock extends InstallationManager
     {
     }
 
-    public function execute(RepositoryInterface $repo, array $operations, $devMode = true, $runScripts = true)
+    public function execute(InstalledRepositoryInterface $repo, array $operations, $devMode = true, $runScripts = true)
     {
         foreach ($operations as $operation) {
             $method = $operation->getOperationType();
@@ -53,14 +53,14 @@ class InstallationManagerMock extends InstallationManager
         return $repo->hasPackage($package);
     }
 
-    public function install(RepositoryInterface $repo, InstallOperation $operation)
+    public function install(InstalledRepositoryInterface $repo, InstallOperation $operation)
     {
         $this->installed[] = $operation->getPackage();
         $this->trace[] = strip_tags((string) $operation);
         $repo->addPackage(clone $operation->getPackage());
     }
 
-    public function update(RepositoryInterface $repo, UpdateOperation $operation)
+    public function update(InstalledRepositoryInterface $repo, UpdateOperation $operation)
     {
         $this->updated[] = array($operation->getInitialPackage(), $operation->getTargetPackage());
         $this->trace[] = strip_tags((string) $operation);
@@ -70,14 +70,14 @@ class InstallationManagerMock extends InstallationManager
         }
     }
 
-    public function uninstall(RepositoryInterface $repo, UninstallOperation $operation)
+    public function uninstall(InstalledRepositoryInterface $repo, UninstallOperation $operation)
     {
         $this->uninstalled[] = $operation->getPackage();
         $this->trace[] = strip_tags((string) $operation);
         $repo->removePackage($operation->getPackage());
     }
 
-    public function markAliasInstalled(RepositoryInterface $repo, MarkAliasInstalledOperation $operation)
+    public function markAliasInstalled(InstalledRepositoryInterface $repo, MarkAliasInstalledOperation $operation)
     {
         $package = $operation->getPackage();
 
@@ -87,7 +87,7 @@ class InstallationManagerMock extends InstallationManager
         parent::markAliasInstalled($repo, $operation);
     }
 
-    public function markAliasUninstalled(RepositoryInterface $repo, MarkAliasUninstalledOperation $operation)
+    public function markAliasUninstalled(InstalledRepositoryInterface $repo, MarkAliasUninstalledOperation $operation)
     {
         $this->uninstalled[] = $operation->getPackage();
         $this->trace[] = strip_tags((string) $operation);

tests/Composer/Test/Package/Archiver/ArchiverTest.php

@@ -15,7 +15,7 @@ namespace Composer\Test\Package\Archiver;
 use Composer\Test\TestCase;
 use Composer\Util\Filesystem;
 use Composer\Util\ProcessExecutor;
-use Composer\Package\Package;
+use Composer\Package\CompletePackage;
 
 abstract class ArchiverTest extends TestCase
 {
@@ -49,11 +49,11 @@ abstract class ArchiverTest extends TestCase
     /**
      * Util method to quickly setup a package using the source path built.
      *
-     * @return \Composer\Package\Package
+     * @return CompletePackage
      */
     protected function setupPackage()
     {
-        $package = new Package('archivertest/archivertest', 'master', 'master');
+        $package = new CompletePackage('archivertest/archivertest', 'master', 'master');
         $package->setSourceUrl(realpath($this->testDir));
         $package->setSourceReference('master');
         $package->setSourceType('git');

tests/Composer/Test/Package/RootAliasPackageTest.php

@@ -82,7 +82,7 @@ class RootAliasPackageTest extends TestCase
 
     protected function getMockRootPackageInterface()
     {
-        $root = $this->prophesize('Composer\\Package\\RootPackageInterface');
+        $root = $this->prophesize('Composer\\Package\\RootPackage');
         $root->getName()->willReturn('something/something')->shouldBeCalled();
         $root->getRequires()->willReturn(array())->shouldBeCalled();
         $root->getDevRequires()->willReturn(array())->shouldBeCalled();

tests/Composer/Test/Plugin/PluginInstallerTest.php

@@ -54,17 +54,17 @@ class PluginInstallerTest extends TestCase
     protected $directory;
 
     /**
-     * @var \PHPUnit_Framework_MockObject_MockObject
+     * @var \PHPUnit\Framework\MockObject\MockObject
      */
     protected $im;
 
     /**
-     * @var \PHPUnit_Framework_MockObject_MockObject
+     * @var \PHPUnit\Framework\MockObject\MockObject
      */
     protected $repository;
 
     /**
-     * @var \PHPUnit_Framework_MockObject_MockObject
+     * @var BufferIO
      */
     protected $io;
 
@@ -337,6 +337,7 @@ class PluginInstallerTest extends TestCase
         $installer = new PluginInstaller($this->io, $this->composer);
         $this->pm->loadInstalledPlugins();
 
+        /** @var \Composer\Plugin\Capability\CommandProvider[] $caps */
         $caps = $this->pm->getPluginCapabilities('Composer\Plugin\Capability\CommandProvider', array('composer' => $this->composer, 'io' => $this->io));
         $this->assertCount(1, $caps);
         $this->assertInstanceOf('Composer\Plugin\Capability\CommandProvider', $caps[0]);
@@ -368,6 +369,7 @@ class PluginInstallerTest extends TestCase
                    return array($capabilityApi => $capabilityImplementation);
                }));
 
+        /** @var \Composer\Test\Plugin\Mock\Capability $capability */
         $capability = $this->pm->getPluginCapability($plugin, $capabilityApi, array('a' => 1, 'b' => 2));
 
         $this->assertInstanceOf($capabilityApi, $capability);

tests/Composer/Test/Repository/RepositoryManagerTest.php

@@ -119,6 +119,7 @@ class RepositoryManagerTest extends TestCase
         );
 
         $rm->setRepositoryClass('path', 'Composer\Repository\PathRepository');
+        /** @var \Composer\Repository\FilterRepository $repo */
         $repo = $rm->createRepository('path', array('type' => 'path', 'url' => __DIR__, 'only' => array('foo/bar')));
 
         $this->assertInstanceOf('Composer\Repository\FilterRepository', $repo);

tests/Composer/Test/TestCase.php

@@ -118,7 +118,7 @@ abstract class TestCase extends PolyfillTestCase
      *
      * @param string $executableName The name of the binary to test.
      *
-     * @throws \PHPUnit_Framework_SkippedTestError
+     * @throws \PHPUnit\Framework\SkippedTestError
      */
     protected function skipIfNotExecutable($executableName)
     {

tests/Composer/Test/Util/ErrorHandlerTest.php

@@ -42,6 +42,7 @@ class ErrorHandlerTest extends TestCase
         }
 
         $array = array('foo' => 'bar');
+        // @phpstan-ignore-next-line
         $array['baz'];
     }
 

tests/Composer/Test/Util/GitTest.php

@@ -23,13 +23,13 @@ class GitTest extends TestCase
 {
     /** @var Git */
     private $git;
-    /** @var IOInterface&\PHPUnit_Framework_MockObject_MockObject */
+    /** @var IOInterface&\PHPUnit\Framework\MockObject\MockObject */
     private $io;
-    /** @var Config&\PHPUnit_Framework_MockObject_MockObject */
+    /** @var Config&\PHPUnit\Framework\MockObject\MockObject */
     private $config;
-    /** @var ProcessExecutor&\PHPUnit_Framework_MockObject_MockObject */
+    /** @var ProcessExecutor&\PHPUnit\Framework\MockObject\MockObject */
     private $process;
-    /** @var Filesystem&\PHPUnit_Framework_MockObject_MockObject */
+    /** @var Filesystem&\PHPUnit\Framework\MockObject\MockObject */
     private $fs;
 
     protected function setUp()