PHPStan level 6 in src/Composer/Repository (#10197)

src/Composer/Command/BaseDependencyCommand.php

@@ -14,6 +14,7 @@ namespace Composer\Command;
 
 use Composer\Package\Link;
 use Composer\Package\PackageInterface;
+use Composer\Package\CompletePackageInterface;
 use Composer\Package\RootPackage;
 use Composer\Repository\InstalledArrayRepository;
 use Composer\Repository\CompositeRepository;
@@ -121,7 +122,7 @@ class BaseDependencyCommand extends BaseCommand
         } elseif ($renderTree) {
             $this->initStyles($output);
             $root = $packages[0];
-            $this->getIO()->write(sprintf('<info>%s</info> %s %s', $root->getPrettyName(), $root->getPrettyVersion(), $root->getDescription()));
+            $this->getIO()->write(sprintf('<info>%s</info> %s %s', $root->getPrettyName(), $root->getPrettyVersion(), $root instanceof CompletePackageInterface ? $root->getDescription() : ''));
             $this->printTree($results);
         } else {
             $this->printTable($output, $results);

src/Composer/Command/ShowCommand.php

@@ -430,7 +430,7 @@ EOT
                             $packageViewData['latest-status'] = $this->getUpdateStatus($latestPackage, $package);
                             $latestLength = max($latestLength, strlen($latestPackage->getFullPrettyVersion()));
                         }
-                        if ($writeDescription) {
+                        if ($writeDescription && $package instanceof CompletePackageInterface) {
                             $packageViewData['description'] = $package->getDescription();
                         }
                         if ($writePath) {

src/Composer/Repository/ArrayRepository.php

@@ -38,6 +38,9 @@ class ArrayRepository implements RepositoryInterface
      */
     protected $packageMap = null;
 
+    /**
+     * @param array<PackageInterface> $packages
+     */
     public function __construct(array $packages = array())
     {
         foreach ($packages as $package) {
@@ -188,6 +191,8 @@ class ArrayRepository implements RepositoryInterface
      * Adds a new package to the repository
      *
      * @param PackageInterface $package
+     *
+     * @return void
      */
     public function addPackage(PackageInterface $package)
     {
@@ -236,6 +241,9 @@ class ArrayRepository implements RepositoryInterface
 
     /**
      * @phpstan-param PackageInterface&BasePackage $package
+     * @param string $alias
+     * @param string $prettyAlias
+     *
      * @return AliasPackage|CompleteAliasPackage
      */
     protected function createAliasPackage(PackageInterface $package, $alias, $prettyAlias)
@@ -255,6 +263,8 @@ class ArrayRepository implements RepositoryInterface
      * Removes package from repository.
      *
      * @param PackageInterface $package package instance
+     *
+     * @return void
      */
     public function removePackage(PackageInterface $package)
     {
@@ -305,6 +315,8 @@ class ArrayRepository implements RepositoryInterface
 
     /**
      * Initializes the packages array. Mostly meant as an extension point.
+     *
+     * @return void
      */
     protected function initialize()
     {

src/Composer/Repository/ArtifactRepository.php

@@ -14,6 +14,7 @@ namespace Composer\Repository;
 
 use Composer\IO\IOInterface;
 use Composer\Json\JsonFile;
+use Composer\Package\BasePackage;
 use Composer\Package\Loader\ArrayLoader;
 use Composer\Package\Loader\LoaderInterface;
 use Composer\Util\Tar;
@@ -29,11 +30,14 @@ class ArtifactRepository extends ArrayRepository implements ConfigurableReposito
 
     /** @var string */
     protected $lookup;
-    /** @var mixed[] */
+    /** @var array{url: string} */
     protected $repoConfig;
     /** @var IOInterface */
     private $io;
 
+    /**
+     * @param array{url: string} $repoConfig
+     */
     public function __construct(array $repoConfig, IOInterface $io)
     {
         parent::__construct();
@@ -64,6 +68,11 @@ class ArtifactRepository extends ArrayRepository implements ConfigurableReposito
         $this->scanDirectory($this->lookup);
     }
 
+    /**
+     * @param string $path
+     *
+     * @return void
+     */
     private function scanDirectory($path)
     {
         $io = $this->io;
@@ -90,6 +99,9 @@ class ArtifactRepository extends ArrayRepository implements ConfigurableReposito
         }
     }
 
+    /**
+     * @return ?BasePackage
+     */
     private function getComposerInformation(\SplFileInfo $file)
     {
         $json = null;
@@ -114,7 +126,7 @@ class ArtifactRepository extends ArrayRepository implements ConfigurableReposito
         }
 
         if (null === $json) {
-            return false;
+            return null;
         }
 
         $package = JsonFile::parseJson($json, $file->getPathname().'#composer.json');

src/Composer/Repository/ComposerRepository.php

@@ -128,6 +128,10 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
      */
     public $versionParser;
 
+    /**
+     * @param array<string, mixed> $repoConfig
+     * @phpstan-param array{url: string, options?: mixed[], type?: 'composer', allow_ssl_downgrade?: bool} $repoConfig
+     */
     public function __construct(array $repoConfig, IOInterface $io, Config $config, HttpDownloader $httpDownloader, EventDispatcher $eventDispatcher = null)
     {
         parent::__construct();
@@ -263,6 +267,13 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return parent::findPackages($name, $constraint);
     }
 
+    /**
+     * @param array<BasePackage> $packages
+     * @param ConstraintInterface|null $constraint
+     * @param bool $returnFirstMatch
+     *
+     * @return BasePackage|array<BasePackage>|null
+     */
     private function filterPackages(array $packages, $constraint = null, $returnFirstMatch = false)
     {
         if (null === $constraint) {
@@ -324,6 +335,11 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return parent::getPackages();
     }
 
+    /**
+     * @param string|null $packageFilter
+     *
+     * @return string[]
+     */
     public function getPackageNames($packageFilter = null)
     {
         $hasProviders = $this->hasProviders();
@@ -523,6 +539,9 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return $result;
     }
 
+    /**
+     * @return string[]
+     */
     private function getProviderNames()
     {
         $this->loadRootServerFile();
@@ -543,6 +562,9 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return array();
     }
 
+    /**
+     * @return void
+     */
     protected function configurePackageTransportOptions(PackageInterface $package)
     {
         foreach ($package->getDistUrls() as $url) {
@@ -554,6 +576,9 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         }
     }
 
+    /**
+     * @return bool
+     */
     private function hasProviders()
     {
         $this->loadRootServerFile();
@@ -563,7 +588,13 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
 
     /**
      * @param  string      $name package name
-     * @return array|mixed
+     * @param array<string, int>|null $acceptableStabilities
+     * @phpstan-param array<string, BasePackage::STABILITY_*>|null $acceptableStabilities
+     * @param array<string, int>|null $stabilityFlags an array of package name => BasePackage::STABILITY_* value
+     * @phpstan-param array<string, BasePackage::STABILITY_*>|null $stabilityFlags
+     * @param array<string, array<string, PackageInterface>> $alreadyLoaded
+     *
+     * @return array<string, BasePackage>
      */
     private function whatProvides($name, array $acceptableStabilities = null, array $stabilityFlags = null, array $alreadyLoaded = array())
     {
@@ -724,7 +755,14 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
     }
 
     /**
-     * @param array $packageNames array of package name => ConstraintInterface|null - if a constraint is provided, only packages matching it will be loaded
+     * @param array<string, ConstraintInterface|null> $packageNames array of package name => ConstraintInterface|null - if a constraint is provided, only packages matching it will be loaded
+     * @param array<string, int>|null $acceptableStabilities
+     * @phpstan-param array<string, BasePackage::STABILITY_*>|null $acceptableStabilities
+     * @param array<string, int>|null $stabilityFlags an array of package name => BasePackage::STABILITY_* value
+     * @phpstan-param array<string, BasePackage::STABILITY_*>|null $stabilityFlags
+     * @param array<string, array<string, PackageInterface>> $alreadyLoaded
+     *
+     * @return array{namesFound: array<string, true>, packages: array<string, BasePackage>}
      */
     private function loadAsyncPackages(array $packageNames, array $acceptableStabilities = null, array $stabilityFlags = null, array $alreadyLoaded = array())
     {
@@ -829,8 +867,17 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
     /**
      * TODO v3 should make this private once we can drop PHP 5.3 support
      *
-     * @param string $name package name (must be lowercased already)
      * @private
+     *
+     * @param ConstraintInterface|null $constraint
+     * @param string $name package name (must be lowercased already)
+     * @param array<string, mixed> $versionData
+     * @param array<string, int>|null $acceptableStabilities
+     * @phpstan-param array<string, BasePackage::STABILITY_*>|null $acceptableStabilities
+     * @param array<string, int>|null $stabilityFlags an array of package name => BasePackage::STABILITY_* value
+     * @phpstan-param array<string, BasePackage::STABILITY_*>|null $stabilityFlags
+     *
+     * @return bool
      */
     public function isVersionAcceptable($constraint, $name, $versionData, array $acceptableStabilities = null, array $stabilityFlags = null)
     {
@@ -855,6 +902,9 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return false;
     }
 
+    /**
+     * @return string
+     */
     private function getPackagesJsonUrl()
     {
         $jsonUrlParts = parse_url($this->url);
@@ -866,6 +916,9 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return $this->url . '/packages.json';
     }
 
+    /**
+     * @return array<string, mixed>
+     */
     protected function loadRootServerFile()
     {
         if (null !== $this->rootData) {
@@ -977,6 +1030,11 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return $this->rootData = $data;
     }
 
+    /**
+     * @param string $url
+     *
+     * @return string
+     */
     private function canonicalizeUrl($url)
     {
         if ('/' === $url[0]) {
@@ -990,6 +1048,9 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return $url;
     }
 
+    /**
+     * @return array[]
+     */
     private function loadDataFromServer()
     {
         $data = $this->loadRootServerFile();
@@ -997,6 +1058,9 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return $this->loadIncludes($data);
     }
 
+    /**
+     * @return bool
+     */
     private function hasPartialPackages()
     {
         if ($this->hasPartialPackages && null === $this->partialPackagesByName) {
@@ -1006,6 +1070,11 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return $this->hasPartialPackages;
     }
 
+    /**
+     * @param array{providers?: array, provider-includes?: array} $data
+     *
+     * @return void
+     */
     private function loadProviderListings($data)
     {
         if (isset($data['providers'])) {
@@ -1031,6 +1100,11 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         }
     }
 
+    /**
+     * @param array[] $data
+     *
+     * @return array[]
+     */
     private function loadIncludes($data)
     {
         $packages = array();
@@ -1072,8 +1146,11 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
 
     /**
      * TODO v3 should make this private once we can drop PHP 5.3 support
-     *
      * @private
+     *
+     * @param array[] $packages
+     * @param string|null $source
+     *
      * @return list<CompletePackage|CompleteAliasPackage>
      */
     public function createPackages(array $packages, $source = null)
@@ -1105,6 +1182,14 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         }
     }
 
+    /**
+     * @param string $filename
+     * @param string|null $cacheKey
+     * @param string|null $sha256
+     * @param bool $storeLastModifiedTime
+     *
+     * @return array<mixed>
+     */
     protected function fetchFile($filename, $cacheKey = null, $sha256 = null, $storeLastModifiedTime = false)
     {
         if (null === $cacheKey) {
@@ -1218,6 +1303,13 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         return $data;
     }
 
+    /**
+     * @param string $filename
+     * @param string $cacheKey
+     * @param string $lastModifiedTime
+     *
+     * @return array<mixed>|true
+     */
     private function fetchFileIfLastModified($filename, $cacheKey, $lastModifiedTime)
     {
         $retries = 3;
@@ -1283,8 +1375,17 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
                 return true;
             }
         }
+
+        throw new \LogicException('Should not happen');
     }
 
+    /**
+     * @param string $filename
+     * @param string $cacheKey
+     * @param string|null $lastModifiedTime
+     *
+     * @return \React\Promise\PromiseInterface
+     */
     private function asyncFetchFile($filename, $cacheKey, $lastModifiedTime = null)
     {
         $retries = 3;
@@ -1410,6 +1511,8 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
      * This initializes the packages key of a partial packages.json that contain some packages inlined + a providers-lazy-url
      *
      * This should only be called once
+     *
+     * @return void
      */
     private function initializePartialPackages()
     {

src/Composer/Repository/CompositeRepository.php

@@ -49,7 +49,7 @@ class CompositeRepository implements RepositoryInterface
     /**
      * Returns all the wrapped repositories
      *
-     * @return array
+     * @return RepositoryInterface[]
      */
     public function getRepositories()
     {
@@ -164,7 +164,7 @@ class CompositeRepository implements RepositoryInterface
     }
 
     /**
-     * {@inheritdoc}
+     * @return void
      */
     public function removePackage(PackageInterface $package)
     {
@@ -193,6 +193,8 @@ class CompositeRepository implements RepositoryInterface
     /**
      * Add a repository.
      * @param RepositoryInterface $repository
+     *
+     * @return void
      */
     public function addRepository(RepositoryInterface $repository)
     {

src/Composer/Repository/FilesystemRepository.php

@@ -154,6 +154,12 @@ class FilesystemRepository extends WritableArrayRepository
         }
     }
 
+    /**
+     * @param array<mixed> $array
+     * @param int $level
+     *
+     * @return string
+     */
     private function dumpToPhpCode(array $array = array(), $level = 0)
     {
         $lines = "array(\n";
@@ -186,7 +192,11 @@ class FilesystemRepository extends WritableArrayRepository
     }
 
     /**
-     * @return ?array
+     * @param array<string, string> $installPaths
+     * @param bool $devMode
+     * @param string $repoDir
+     *
+     * @return ?array<mixed>
      */
     private function generateInstalledVersions(InstallationManager $installationManager, array $installPaths, $devMode, $repoDir)
     {

src/Composer/Repository/FilterRepository.php

@@ -31,6 +31,9 @@ class FilterRepository implements RepositoryInterface
     /** @var RepositoryInterface */
     private $repo;
 
+    /**
+     * @param array{only?: array<string>, exclude?: array<string>, canonical?: bool} $options
+     */
     public function __construct(RepositoryInterface $repo, array $options)
     {
         if (isset($options['only'])) {
@@ -191,6 +194,11 @@ class FilterRepository implements RepositoryInterface
         return 0;
     }
 
+    /**
+     * @param string $name
+     *
+     * @return bool
+     */
     private function isAllowed($name)
     {
         if (!$this->only && !$this->exclude) {

src/Composer/Repository/InstalledRepository.php

@@ -12,6 +12,8 @@
 
 namespace Composer\Repository;
 
+use Composer\Package\BasePackage;
+use Composer\Package\PackageInterface;
 use Composer\Package\Version\VersionParser;
 use Composer\Semver\Constraint\ConstraintInterface;
 use Composer\Semver\Constraint\Constraint;
@@ -30,6 +32,12 @@ use Composer\Package\Link;
  */
 class InstalledRepository extends CompositeRepository
 {
+    /**
+     * @param string $name
+     * @param ConstraintInterface|string|null $constraint
+     *
+     * @return BasePackage[]
+     */
     public function findPackagesWithReplacersAndProviders($name, $constraint = null)
     {
         $name = strtolower($name);
@@ -52,7 +60,7 @@ class InstalledRepository extends CompositeRepository
                 foreach (array_merge($candidate->getProvides(), $candidate->getReplaces()) as $link) {
                     if (
                         $name === $link->getTarget()
-                        && ($constraint === null || $link->getConstraint() === null || $constraint->matches($link->getConstraint()))
+                        && ($constraint === null || $constraint->matches($link->getConstraint()))
                     ) {
                         $matches[] = $candidate;
                         continue 2;
@@ -75,7 +83,9 @@ class InstalledRepository extends CompositeRepository
      * @param  bool                     $invert        Whether to invert matches to discover reasons for the package *NOT* to be installed.
      * @param  bool                     $recurse       Whether to recursively expand the requirement tree up to the root package.
      * @param  string[]                 $packagesFound Used internally when recurring
-     * @return array                    An associative array of arrays as described above.
+     *
+     * @return array[] An associative array of arrays as described above.
+     * @phpstan-return array<array{0: PackageInterface, 1: Link, 2: mixed[]|bool}>
      */
     public function getDependents($needle, $constraint = null, $invert = false, $recurse = true, $packagesFound = null)
     {
@@ -247,8 +257,7 @@ class InstalledRepository extends CompositeRepository
     }
 
     /**
-     * Add a repository.
+     * {@inheritDoc}
-     * @param RepositoryInterface $repository
      */
     public function addRepository(RepositoryInterface $repository)
     {
@@ -258,7 +267,9 @@ class InstalledRepository extends CompositeRepository
             || $repository instanceof RootPackageRepository
             || $repository instanceof PlatformRepository
         ) {
-            return parent::addRepository($repository);
+            parent::addRepository($repository);
+
+            return;
         }
 
         throw new \LogicException('An InstalledRepository can not contain a repository of type '.get_class($repository).' ('.$repository->getRepoName().')');

src/Composer/Repository/PackageRepository.php

@@ -28,7 +28,7 @@ class PackageRepository extends ArrayRepository
     /**
      * Initializes filesystem repository.
      *
-     * @param array $config package definition
+     * @param array{package: array} $config package definition
      */
     public function __construct(array $config)
     {

src/Composer/Repository/PathRepository.php

@@ -95,7 +95,7 @@ class PathRepository extends ArrayRepository implements ConfigurableRepositoryIn
     /**
      * Initializes path repository.
      *
-     * @param array       $repoConfig
+     * @param array{url: string, options?: array{symlink?: bool, relative?: bool, versions?: array<string, string>}} $repoConfig
      * @param IOInterface $io
      * @param Config      $config
      */

src/Composer/Repository/PlatformRepository.php

@@ -57,6 +57,9 @@ class PlatformRepository extends ArrayRepository
     /** @var HhvmDetector */
     private $hhvmDetector;
 
+    /**
+     * @param array<string, string> $overrides
+     */
     public function __construct(array $packages = array(), array $overrides = array(), Runtime $runtime = null, HhvmDetector $hhvmDetector = null)
     {
         $this->runtime = $runtime ?: new Runtime();
@@ -523,6 +526,9 @@ class PlatformRepository extends ArrayRepository
     }
 
     /**
+     * @param array{version: string, name: string} $override
+     * @param string|null $name
+     *
      * @return CompletePackage
      */
     private function addOverriddenPackage(array $override, $name = null)
@@ -545,6 +551,8 @@ class PlatformRepository extends ArrayRepository
      *
      * @param string      $name
      * @param null|string $prettyVersion
+     *
+     * @return void
      */
     private function addExtension($name, $prettyVersion)
     {
@@ -590,6 +598,8 @@ class PlatformRepository extends ArrayRepository
      * @param string|null $description
      * @param string[]    $replaces
      * @param string[]    $provides
+     *
+     * @return void
      */
     private function addLibrary($name, $prettyVersion, $description = null, array $replaces = array(), array $provides = array())
     {
@@ -640,6 +650,7 @@ class PlatformRepository extends ArrayRepository
      * be correct.
      *
      * @internal
+     * @return string|null
      */
     public static function getPlatformPhpVersion()
     {

src/Composer/Repository/RepositoryFactory.php

@@ -73,7 +73,7 @@ class RepositoryFactory
     /**
      * @param  IOInterface         $io
      * @param  Config              $config
-     * @param  array               $repoConfig
+     * @param  array<string, mixed> $repoConfig
      * @return RepositoryInterface
      */
     public static function createRepo(IOInterface $io, Config $config, array $repoConfig, RepositoryManager $rm = null)
@@ -140,6 +140,8 @@ class RepositoryFactory
     }
 
     /**
+     * @param array<int|string, mixed> $repoConfigs
+     *
      * @return RepositoryInterface[]
      */
     private static function createRepos(RepositoryManager $rm, array $repoConfigs)
@@ -168,6 +170,13 @@ class RepositoryFactory
         return $repos;
     }
 
+    /**
+     * @param int|string $index
+     * @param array{url?: string} $repo
+     * @param array<string, mixed> $existingRepos
+     *
+     * @return string
+     */
     public static function generateRepositoryName($index, array $repo, array $existingRepos)
     {
         $name = is_int($index) && isset($repo['url']) ? preg_replace('{^https?://}i', '', $repo['url']) : $index;

src/Composer/Repository/RepositoryInterface.php

@@ -43,8 +43,7 @@ interface RepositoryInterface extends \Countable
      * @param string                     $name       package name
      * @param string|ConstraintInterface $constraint package version or version constraint to match against
      *
-     * @return PackageInterface|null
+     * @return BasePackage|null
-     * @phpstan-return (BasePackage&PackageInterface)|null
      */
     public function findPackage($name, $constraint);
 
@@ -54,16 +53,14 @@ interface RepositoryInterface extends \Countable
      * @param string                     $name       package name
      * @param string|ConstraintInterface $constraint package version or version constraint to match against
      *
-     * @return PackageInterface[]
+     * @return BasePackage[]
-     * @phpstan-return array<BasePackage&PackageInterface>
      */
     public function findPackages($name, $constraint = null);
 
     /**
      * Returns list of registered packages.
      *
-     * @return PackageInterface[]
+     * @return BasePackage[]
-     * @phpstan-return array<BasePackage&PackageInterface>
      */
     public function getPackages();
 
@@ -81,7 +78,7 @@ interface RepositoryInterface extends \Countable
      * @return array
      *
      * @phpstan-param  array<string, ConstraintInterface|null> $packageNameMap
-     * @phpstan-return array{namesFound: string[], packages: array<BasePackage&PackageInterface>}
+     * @phpstan-return array{namesFound: array<string>, packages: array<BasePackage>}
      */
     public function loadPackages(array $packageNameMap, array $acceptableStabilities, array $stabilityFlags, array $alreadyLoaded = array());
 

src/Composer/Repository/RepositoryManager.php

@@ -32,7 +32,7 @@ class RepositoryManager
     private $localRepository;
     /** @var list<RepositoryInterface> */
     private $repositories = array();
-    /** @var array<string, string> */
+    /** @var array<string, class-string<RepositoryInterface>> */
     private $repositoryClasses = array();
     /** @var IOInterface */
     private $io;
@@ -97,6 +97,8 @@ class RepositoryManager
      * Adds repository
      *
      * @param RepositoryInterface $repository repository instance
+     *
+     * @return void
      */
     public function addRepository(RepositoryInterface $repository)
     {
@@ -109,6 +111,8 @@ class RepositoryManager
      * This is useful when injecting additional repositories that should trump Packagist, e.g. from a plugin.
      *
      * @param RepositoryInterface $repository repository instance
+     *
+     * @return void
      */
     public function prependRepository(RepositoryInterface $repository)
     {
@@ -119,7 +123,7 @@ class RepositoryManager
      * Returns a new repository for a specific installation type.
      *
      * @param  string                    $type   repository type
-     * @param  array                     $config repository configuration
+     * @param  array<string, mixed>      $config repository configuration
      * @param  string                    $name   repository name
      * @throws \InvalidArgumentException if repository for provided type is not registered
      * @return RepositoryInterface
@@ -154,7 +158,9 @@ class RepositoryManager
      * Stores repository class for a specific installation type.
      *
      * @param string $type  installation type
-     * @param string $class class name of the repo implementation
+     * @param class-string<RepositoryInterface> $class class name of the repo implementation
+     *
+     * @return void
      */
     public function setRepositoryClass($type, $class)
     {
@@ -175,6 +181,8 @@ class RepositoryManager
      * Sets local repository for the project.
      *
      * @param InstalledRepositoryInterface $repository repository instance
+     *
+     * @return void
      */
     public function setLocalRepository(InstalledRepositoryInterface $repository)
     {

src/Composer/Repository/RepositorySet.php

@@ -23,6 +23,7 @@ use Composer\Package\AliasPackage;
 use Composer\Package\CompleteAliasPackage;
 use Composer\Package\CompletePackage;
 use Composer\Package\CompletePackageInterface;
+use Composer\Package\PackageInterface;
 use Composer\Semver\Constraint\ConstraintInterface;
 use Composer\Package\Version\StabilityFilter;
 
@@ -113,6 +114,11 @@ class RepositorySet
         }
     }
 
+    /**
+     * @param bool $allow
+     *
+     * @return void
+     */
     public function allowInstalledRepositories($allow = true)
     {
         $this->allowInstalledRepositories = $allow;
@@ -134,6 +140,8 @@ class RepositorySet
      * repository the search for that package ends, and following repos will not be consulted.
      *
      * @param RepositoryInterface $repo A package repository
+     *
+     * @return void
      */
     public function addRepository(RepositoryInterface $repo)
     {
@@ -160,7 +168,7 @@ class RepositorySet
      * @param  string                   $name
      * @param  ConstraintInterface|null $constraint
      * @param  int                      $flags      any of the ALLOW_* constants from this class to tweak what is returned
-     * @return array
+     * @return BasePackage[]
      */
     public function findPackages($name, ConstraintInterface $constraint = null, $flags = 0)
     {
@@ -292,12 +300,22 @@ class RepositorySet
         return new Pool($packages);
     }
 
-    // TODO unify this with above in some simpler version without "request"?
+    /**
+     * @param string $packageName
+     *
+     * @return Pool
+     */
     public function createPoolForPackage($packageName, LockArrayRepository $lockedRepo = null)
     {
+        // TODO unify this with above in some simpler version without "request"?
         return $this->createPoolForPackages(array($packageName), $lockedRepo);
     }
 
+    /**
+     * @param string[] $packageNames
+     *
+     * @return Pool
+     */
     public function createPoolForPackages($packageNames, LockArrayRepository $lockedRepo = null)
     {
         $request = new Request($lockedRepo);
@@ -313,6 +331,12 @@ class RepositorySet
         return $this->createPool($request, new NullIO());
     }
 
+    /**
+     * @param array[] $aliases
+     * @phpstan-param list<array{package: string, version: string, alias: string, alias_normalized: string}> $aliases
+     *
+     * @return array<string, array<string, array{alias: string, alias_normalized: string}>>
+     */
     private static function getRootAliasesPerPackage(array $aliases)
     {
         $normalizedAliases = array();

src/Composer/Repository/Vcs/BitbucketDriver.php

@@ -393,11 +393,11 @@ abstract class BitbucketDriver extends VcsDriver
                 }
 
                 if (!$this->io->isInteractive() && $fetchingRepoData) {
-                    if ($this->attemptCloneFallback()) {
+                    $this->attemptCloneFallback();
+
                     return new Response(array('url' => 'dummy'), 200, array(), 'null');
                 }
             }
-            }
 
             throw $e;
         }
@@ -412,6 +412,9 @@ abstract class BitbucketDriver extends VcsDriver
 
     /**
      * @phpstan-impure
+     *
+     * @return true
+     * @throws \RuntimeException
      */
     protected function attemptCloneFallback()
     {
@@ -437,7 +440,7 @@ abstract class BitbucketDriver extends VcsDriver
     abstract protected function setupFallbackDriver($url);
 
     /**
-     * @param  array $cloneLinks
+     * @param  array<array{name: string, href: string}> $cloneLinks
      * @return void
      */
     protected function parseCloneUrls(array $cloneLinks)
@@ -452,7 +455,7 @@ abstract class BitbucketDriver extends VcsDriver
     }
 
     /**
-     * @return array|null
+     * @return (array{name: string}&mixed[])|null
      */
     protected function getMainBranchData()
     {

src/Composer/Repository/Vcs/FossilDriver.php

@@ -67,6 +67,8 @@ class FossilDriver extends VcsDriver
 
     /**
      * Check that fossil can be invoked via command line.
+     *
+     * @return void
      */
     protected function checkFossil()
     {
@@ -77,6 +79,8 @@ class FossilDriver extends VcsDriver
 
     /**
      * Clone or update existing local fossil repository.
+     *
+     * @return void
      */
     protected function updateLocalRepo()
     {

src/Composer/Repository/Vcs/GitHubDriver.php

@@ -77,6 +77,9 @@ class GitHubDriver extends VcsDriver
         $this->fetchRootIdentifier();
     }
 
+    /**
+     * @return string
+     */
     public function getRepositoryUrl()
     {
         return 'https://'.$this->originUrl.'/'.$this->owner.'/'.$this->repository;
@@ -107,7 +110,7 @@ class GitHubDriver extends VcsDriver
     }
 
     /**
-     * {@inheritDoc}
+     * @return string
      */
     protected function getApiUrl()
     {
@@ -192,6 +195,9 @@ class GitHubDriver extends VcsDriver
         return $this->infoCache[$identifier];
     }
 
+    /**
+     * @return array<int, array{type: string, url: string}>|false
+     */
     private function getFundingInfo()
     {
         if (null !== $this->fundingInfo) {
@@ -388,7 +394,7 @@ class GitHubDriver extends VcsDriver
     /**
      * Gives back the loaded <github-api>/repos/<owner>/<repo> result
      *
-     * @return array|null
+     * @return mixed[]|null
      */
     public function getRepoData()
     {
@@ -413,6 +419,8 @@ class GitHubDriver extends VcsDriver
 
     /**
      * {@inheritDoc}
+     *
+     * @param bool $fetchingRepoData
      */
     protected function getContents($url, $fetchingRepoData = false)
     {
@@ -434,10 +442,10 @@ class GitHubDriver extends VcsDriver
                     }
 
                     if (!$this->io->isInteractive()) {
-                        if ($this->attemptCloneFallback()) {
+                        $this->attemptCloneFallback();
+
                         return new Response(array('url' => 'dummy'), 200, array(), 'null');
                     }
-                    }
 
                     $scopesIssued = array();
                     $scopesNeeded = array();
@@ -464,10 +472,10 @@ class GitHubDriver extends VcsDriver
                     }
 
                     if (!$this->io->isInteractive() && $fetchingRepoData) {
-                        if ($this->attemptCloneFallback()) {
+                        $this->attemptCloneFallback();
+
                         return new Response(array('url' => 'dummy'), 200, array(), 'null');
                     }
-                    }
 
                     $rateLimited = $gitHubUtil->isRateLimited((array) $e->getHeaders());
 
@@ -502,6 +510,7 @@ class GitHubDriver extends VcsDriver
     /**
      * Fetch root identifier from GitHub
      *
+     * @return void
      * @throws TransportException
      */
     protected function fetchRootIdentifier()
@@ -540,6 +549,12 @@ class GitHubDriver extends VcsDriver
         $this->isArchived = !empty($this->repoData['archived']);
     }
 
+    /**
+     * @phpstan-impure
+     *
+     * @return true
+     * @throws \RuntimeException
+     */
     protected function attemptCloneFallback()
     {
         $this->isPrivate = true;
@@ -560,6 +575,11 @@ class GitHubDriver extends VcsDriver
         }
     }
 
+    /**
+     * @param string $url
+     *
+     * @return void
+     */
     protected function setupGitDriver($url)
     {
         $this->gitDriver = new GitDriver(
@@ -572,12 +592,14 @@ class GitHubDriver extends VcsDriver
         $this->gitDriver->initialize();
     }
 
+    /**
+     * @return string|null
+     */
     protected function getNextPage(Response $response)
     {
         $header = $response->getHeader('link');
-
         if (!$header) {
-            return;
+            return null;
         }
 
         $links = explode(',', $header);
@@ -586,5 +608,7 @@ class GitHubDriver extends VcsDriver
                 return $match[1];
             }
         }
+
+        return null;
     }
 }

src/Composer/Repository/Vcs/GitLabDriver.php

@@ -132,6 +132,8 @@ class GitLabDriver extends VcsDriver
      * Mainly useful for tests.
      *
      * @internal
+     *
+     * @return void
      */
     public function setHttpDownloader(HttpDownloader $httpDownloader)
     {
@@ -223,7 +225,7 @@ class GitLabDriver extends VcsDriver
     }
 
     /**
-     * {@inheritDoc}
+     * @return string
      */
     public function getRepositoryUrl()
     {
@@ -373,6 +375,9 @@ class GitLabDriver extends VcsDriver
         return $references;
     }
 
+    /**
+     * @return void
+     */
     protected function fetchProject()
     {
         // we need to fetch the default branch from the api
@@ -386,6 +391,12 @@ class GitLabDriver extends VcsDriver
         }
     }
 
+    /**
+     * @phpstan-impure
+     *
+     * @return true
+     * @throws \RuntimeException
+     */
     protected function attemptCloneFallback()
     {
         if ($this->isPrivate === false) {
@@ -423,11 +434,19 @@ class GitLabDriver extends VcsDriver
         return 'git@' . $this->originUrl . ':'.$this->namespace.'/'.$this->repository.'.git';
     }
 
+    /**
+     * @return string
+     */
     protected function generatePublicUrl()
     {
         return $this->scheme . '://' . $this->originUrl . '/'.$this->namespace.'/'.$this->repository.'.git';
     }
 
+    /**
+     * @param string $url
+     *
+     * @return void
+     */
     protected function setupGitDriver($url)
     {
         $this->gitDriver = new GitDriver(
@@ -442,6 +461,8 @@ class GitLabDriver extends VcsDriver
 
     /**
      * {@inheritDoc}
+     *
+     * @param bool $fetchingRepoData
      */
     protected function getContents($url, $fetchingRepoData = false)
     {
@@ -470,7 +491,9 @@ class GitLabDriver extends VcsDriver
                     if (!$moreThanGuestAccess) {
                         $this->io->writeError('<warning>GitLab token with Guest only access detected</warning>');
 
-                        return $this->attemptCloneFallback();
+                        $this->attemptCloneFallback();
+
+                        return new Response(array('url' => 'dummy'), 200, array(), 'null');
                     }
                 }
 
@@ -501,10 +524,10 @@ class GitLabDriver extends VcsDriver
                     }
 
                     if (!$this->io->isInteractive()) {
-                        if ($this->attemptCloneFallback()) {
+                        $this->attemptCloneFallback();
+
                         return new Response(array('url' => 'dummy'), 200, array(), 'null');
                     }
-                    }
                     $this->io->writeError('<warning>Failed to download ' . $this->namespace . '/' . $this->repository . ':' . $e->getMessage() . '</warning>');
                     $gitLabUtil->authorizeOAuthInteractively($this->scheme, $this->originUrl, 'Your credentials are required to fetch private repository metadata (<info>'.$this->url.'</info>)');
 
@@ -516,10 +539,10 @@ class GitLabDriver extends VcsDriver
                     }
 
                     if (!$this->io->isInteractive() && $fetchingRepoData) {
-                        if ($this->attemptCloneFallback()) {
+                        $this->attemptCloneFallback();
+
                         return new Response(array('url' => 'dummy'), 200, array(), 'null');
                     }
-                    }
 
                     throw $e;
 
@@ -558,6 +581,9 @@ class GitLabDriver extends VcsDriver
         return true;
     }
 
+    /**
+     * @return string|null
+     */
     protected function getNextPage(Response $response)
     {
         $header = $response->getHeader('link');
@@ -568,13 +594,17 @@ class GitLabDriver extends VcsDriver
                 return $match[1];
             }
         }
+
+        return null;
     }
 
     /**
-     * @param  array       $configuredDomains
+     * @param  array<string> $configuredDomains
      * @param  string        $guessedDomain
-     * @param  array       $urlParts
+     * @param  array<string> $urlParts
-     * @return bool|string
+     * @param string         $portNumber
+     *
+     * @return string|false
      */
     private static function determineOrigin(array $configuredDomains, $guessedDomain, array &$urlParts, $portNumber)
     {

src/Composer/Repository/Vcs/PerforceDriver.php

@@ -49,6 +49,11 @@ class PerforceDriver extends VcsDriver
         $this->perforce->connectClient();
     }
 
+    /**
+     * @param array<string, mixed> $repoConfig
+     *
+     * @return void
+     */
     private function initPerforce($repoConfig)
     {
         if (!empty($this->perforce)) {
@@ -171,11 +176,17 @@ class PerforceDriver extends VcsDriver
         $this->perforce = null;
     }
 
+    /**
+     * @return string
+     */
     public function getDepot()
     {
         return $this->depot;
     }
 
+    /**
+     * @return string
+     */
     public function getBranch()
     {
         return $this->branch;

src/Composer/Repository/Vcs/VcsDriver.php

@@ -51,7 +51,7 @@ abstract class VcsDriver implements VcsDriverInterface
     /**
      * Constructor.
      *
-     * @param array           $repoConfig     The repository configuration
+     * @param array{url: string}&array<string, mixed>           $repoConfig     The repository configuration
      * @param IOInterface     $io             The IO instance
      * @param Config          $config         The composer configuration
      * @param HttpDownloader  $httpDownloader Remote Filesystem, injectable for mocking
@@ -105,6 +105,11 @@ abstract class VcsDriver implements VcsDriverInterface
         return $this->infoCache[$identifier];
     }
 
+    /**
+     * @param string $identifier
+     *
+     * @return array<string, mixed>|null
+     */
     protected function getBaseComposerInformation($identifier)
     {
         $composerFileContent = $this->getFileContent('composer.json', $identifier);

src/Composer/Repository/VcsRepository.php

@@ -58,7 +58,7 @@ class VcsRepository extends ArrayRepository implements ConfigurableRepositoryInt
     protected $processExecutor;
     /** @var bool */
     protected $branchErrorOccurred = false;
-    /** @var array<string, class-string> */
+    /** @var array<string, class-string<VcsDriverInterface>> */
     private $drivers;
     /** @var ?VcsDriverInterface */
     private $driver;
@@ -69,6 +69,10 @@ class VcsRepository extends ArrayRepository implements ConfigurableRepositoryInt
     /** @var array<'tags'|'branches', array<string, \Throwable>> */
     private $versionTransportExceptions = array();
 
+    /**
+     * @param array{url: string, type?: string}&array<string, mixed> $repoConfig
+     * @param array<string, class-string<VcsDriverInterface>>|null $drivers
+     */
     public function __construct(array $repoConfig, IOInterface $io, Config $config, HttpDownloader $httpDownloader, EventDispatcher $dispatcher = null, ProcessExecutor $process = null, array $drivers = null, VersionCacheInterface $versionCache = null)
     {
         parent::__construct();
@@ -113,11 +117,17 @@ class VcsRepository extends ArrayRepository implements ConfigurableRepositoryInt
         return $this->repoConfig;
     }
 
+    /**
+     * @return void
+     */
     public function setLoader(LoaderInterface $loader)
     {
         $this->loader = $loader;
     }
 
+    /**
+     * @return VcsDriverInterface|null
+     */
     public function getDriver()
     {
         if ($this->driver) {
@@ -149,18 +159,29 @@ class VcsRepository extends ArrayRepository implements ConfigurableRepositoryInt
                 return $this->driver;
             }
         }
+
+        return null;
     }
 
+    /**
+     * @return bool
+     */
     public function hadInvalidBranches()
     {
         return $this->branchErrorOccurred;
     }
 
+    /**
+     * @return string[]
+     */
     public function getEmptyReferences()
     {
         return $this->emptyReferences;
     }
 
+    /**
+     * @return array<'tags'|'branches', array<string, \Throwable>>
+     */
     public function getVersionTransportExceptions()
     {
         return $this->versionTransportExceptions;
@@ -399,6 +420,13 @@ class VcsRepository extends ArrayRepository implements ConfigurableRepositoryInt
         }
     }
 
+    /**
+     * @param VcsDriverInterface $driver
+     * @param array{name?: string, dist?: array{type: string, url: string, reference: string, shasum: string}, source?: array{type: string, url: string, reference: string}} $data
+     * @param string $identifier
+     *
+     * @return array{name: string|null, dist: array{type: string, url: string, reference: string, shasum: string}|null, source: array{type: string, url: string, reference: string}}
+     */
     protected function preProcess(VcsDriverInterface $driver, array $data, $identifier)
     {
         // keep the name of the main identifier for all packages
@@ -417,6 +445,11 @@ class VcsRepository extends ArrayRepository implements ConfigurableRepositoryInt
         return $data;
     }
 
+    /**
+     * @param string $branch
+     *
+     * @return string|false
+     */
     private function validateBranch($branch)
     {
         try {
@@ -432,6 +465,11 @@ class VcsRepository extends ArrayRepository implements ConfigurableRepositoryInt
         return false;
     }
 
+    /**
+     * @param string $version
+     *
+     * @return string|false
+     */
     private function validateTag($version)
     {
         try {
@@ -442,10 +480,19 @@ class VcsRepository extends ArrayRepository implements ConfigurableRepositoryInt
         return false;
     }
 
+    /**
+     * @param string $version
+     * @param string $identifier
+     * @param bool $isVerbose
+     * @param bool $isVeryVerbose
+     * @param bool $isDefaultBranch
+     *
+     * @return \Composer\Package\CompletePackage|\Composer\Package\CompleteAliasPackage|null|false null if no cache present, false if the absence of a version was cached
+     */
     private function getCachedPackageVersion($version, $identifier, $isVerbose, $isVeryVerbose, $isDefaultBranch = false)
     {
         if (!$this->versionCache) {
-            return;
+            return null;
         }
 
         $cachedPackage = $this->versionCache->getVersionPackage($version, $identifier);