<?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\DependencyResolver;
use Composer\Package\AliasPackage;
use Composer\Package\BasePackage;
use Composer\Package\PackageInterface;
use Composer\Semver\Constraint\Constraint;
/**
* @author Nils Adermann <naderman@naderman.de>
* @author Jordi Boggiano <j.boggiano@seld.be>
*/
class DefaultPolicy implements PolicyInterface
{
/** @var bool */
private $preferStable;
/** @var bool */
private $preferLowest;
/**
* @param bool $preferStable
* @param bool $preferLowest
*/
public function __construct($preferStable = false, $preferLowest = false)
{
$this->preferStable = $preferStable;
$this->preferLowest = $preferLowest;
}
/**
* @param string $operator One of Constraint::STR_OP_*
* @return bool
*
* @phpstan-param Constraint::STR_OP_* $operator
*/
public function versionCompare(PackageInterface $a, PackageInterface $b, $operator)
{
if ($this->preferStable && ($stabA = $a->getStability()) !== ($stabB = $b->getStability())) {
return BasePackage::$stabilities[$stabA] < BasePackage::$stabilities[$stabB];
}
$constraint = new Constraint($operator, $b->getVersion());
$version = new Constraint('==', $a->getVersion());
return $constraint->matchSpecific($version, true);
}
/**
* @param int[] $literals
* @param string $requiredPackage
* @return int[]
*/
public function selectPreferredPackages(Pool $pool, array $literals, $requiredPackage = null)
{
$packages = $this->groupLiteralsByName($pool, $literals);
$policy = $this;
foreach ($packages as &$nameLiterals) {
usort($nameLiterals, function ($a, $b) use ($policy, $pool, $requiredPackage) {
return $policy->compareByPriority($pool, $pool->literalToPackage($a), $pool->literalToPackage($b), $requiredPackage, true);
});
}
foreach ($packages as &$sortedLiterals) {
$sortedLiterals = $this->pruneToBestVersion($pool, $sortedLiterals);
$sortedLiterals = $this->pruneRemoteAliases($pool, $sortedLiterals);
}
$selected = \call_user_func_array('array_merge', array_values($packages));
// now sort the result across all packages to respect replaces across packages
usort($selected, function ($a, $b) use ($policy, $pool, $requiredPackage) {
return $policy->compareByPriority($pool, $pool->literalToPackage($a), $pool->literalToPackage($b), $requiredPackage);
});
return $selected;
}
/**
* @param int[] $literals
* @return array<string, int[]>
*/
protected function groupLiteralsByName(Pool $pool, $literals)
{
$packages = array();
foreach ($literals as $literal) {
$packageName = $pool->literalToPackage($literal)->getName();
if (!isset($packages[$packageName])) {
$packages[$packageName] = array();
}
$packages[$packageName][] = $literal;
}
return $packages;
}
/**
* @protected
* @param ?string $requiredPackage
* @param bool $ignoreReplace
* @return int
*/
public function compareByPriority(Pool $pool, BasePackage $a, BasePackage $b, $requiredPackage = null, $ignoreReplace = false)
{
// prefer aliases to the original package
if ($a->getName() === $b->getName()) {
$aAliased = $a instanceof AliasPackage;
$bAliased = $b instanceof AliasPackage;
if ($aAliased && !$bAliased) {
return -1; // use a
}
if (!$aAliased && $bAliased) {
return 1; // use b
}
}
if (!$ignoreReplace) {
// return original, not replaced
if ($this->replaces($a, $b)) {
return 1; // use b
}
if ($this->replaces($b, $a)) {
return -1; // use a
}
// for replacers not replacing each other, put a higher prio on replacing
// packages with the same vendor as the required package
if ($requiredPackage && false !== ($pos = strpos($requiredPackage, '/'))) {
$requiredVendor = substr($requiredPackage, 0, $pos);
$aIsSameVendor = strpos($a->getName(), $requiredVendor) === 0;
$bIsSameVendor = strpos($b->getName(), $requiredVendor) === 0;
if ($bIsSameVendor !== $aIsSameVendor) {
return $aIsSameVendor ? -1 : 1;
}
}
}
// priority equal, sort by package id to make reproducible
if ($a->id === $b->id) {
return 0;
}
return ($a->id < $b->id) ? -1 : 1;
}
/**
* Checks if source replaces a package with the same name as target.
*
* Replace constraints are ignored. This method should only be used for
* prioritisation, not for actual constraint verification.
*
* @return bool
*/
protected function replaces(BasePackage $source, BasePackage $target)
{
foreach ($source->getReplaces() as $link) {
if ($link->getTarget() === $target->getName()
// && (null === $link->getConstraint() ||
// $link->getConstraint()->matches(new Constraint('==', $target->getVersion())))) {
) {
return true;
}
}
return false;
}
/**
* @param int[] $literals
* @return int[]
*/
protected function pruneToBestVersion(Pool $pool, $literals)
{
$operator = $this->preferLowest ? '<' : '>';
$bestLiterals = array($literals[0]);
$bestPackage = $pool->literalToPackage($literals[0]);
foreach ($literals as $i => $literal) {
if (0 === $i) {
continue;
}
$package = $pool->literalToPackage($literal);
if ($this->versionCompare($package, $bestPackage, $operator)) {
$bestPackage = $package;
$bestLiterals = array($literal);
} elseif ($this->versionCompare($package, $bestPackage, '==')) {
$bestLiterals[] = $literal;
}
}
return $bestLiterals;
}
/**
* Assumes that locally aliased (in root package requires) packages take priority over branch-alias ones
*
* If no package is a local alias, nothing happens
*
* @param int[] $literals
* @return int[]
*/
protected function pruneRemoteAliases(Pool $pool, array $literals)
{
$hasLocalAlias = false;
foreach ($literals as $literal) {
$package = $pool->literalToPackage($literal);
if ($package instanceof AliasPackage && $package->isRootPackageAlias()) {
$hasLocalAlias = true;
break;
}
}
if (!$hasLocalAlias) {
return $literals;
}
$selected = array();
foreach ($literals as $literal) {
$package = $pool->literalToPackage($literal);
if ($package instanceof AliasPackage && $package->isRootPackageAlias()) {
$selected[] = $literal;
}
}
return $selected;
}
}