[DowngradePhp82] Add DowngradeReadonlyClassRector to downgrade readon…

…ly class (#2322)

* [DowngradePhp82] Add DowngradeReadonlyClassRector to downgrade final readonly class

* apply readonly property promotion

* fixture

* phpstan

* [ci-review] Rector Rectify

* add DowngradeLevelSetList::DOWN_TO_PHP_81

* add test to ensure no flip-flop between add and removing readonly when downgrade to php 8.0

* more test

* more test

* combination test

* final touch: typo fix

* not property promotion

* static properties cannot be readonly

* static properties cannot be readonly

* note

* note

* note

* test

Co-authored-by: GitHub Action <action@github.com>

config/set/downgrade-php82.php

@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\Config\RectorConfig;
+use Rector\Core\ValueObject\PhpVersion;
+use Rector\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector;
+
+return static function (RectorConfig $rectorConfig): void {
+    $rectorConfig->phpVersion(PhpVersion::PHP_81);
+    $rectorConfig->rule(DowngradeReadonlyClassRector::class);
+};

config/set/level/down-to-php80.php

@@ -3,8 +3,9 @@
 declare(strict_types=1);
 
 use Rector\Config\RectorConfig;
+use Rector\Set\ValueObject\DowngradeLevelSetList;
 use Rector\Set\ValueObject\DowngradeSetList;
 
 return static function (RectorConfig $rectorConfig): void {
-    $rectorConfig->sets([DowngradeSetList::PHP_81]);
+    $rectorConfig->sets([DowngradeLevelSetList::DOWN_TO_PHP_81, DowngradeSetList::PHP_81]);
 };

config/set/level/down-to-php81.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\Config\RectorConfig;
+use Rector\Set\ValueObject\DowngradeSetList;
+
+return static function (RectorConfig $rectorConfig): void {
+    $rectorConfig->sets([DowngradeSetList::PHP_82]);
+};

packages/Set/ValueObject/DowngradeLevelSetList.php

@@ -8,6 +8,11 @@
 
 final class DowngradeLevelSetList implements SetListInterface
 {
+    /**
+     * @var string
+     */
+    public const DOWN_TO_PHP_81 = __DIR__ . '/../../../config/set/level/down-to-php81.php';
+
     /**
      * @var string
      */

packages/Set/ValueObject/DowngradeSetList.php

@@ -62,4 +62,9 @@ final class DowngradeSetList implements SetListInterface
      * @var string
      */
     public const PHP_81 = __DIR__ . '/../../../config/set/downgrade-php81.php';
+
+    /**
+     * @var string
+     */
+    public const PHP_82 = __DIR__ . '/../../../config/set/downgrade-php82.php';
 }

rules-tests/DowngradePhp82/Rector/Class_/DowngradeReadonlyClassRector/DowngradeReadonlyClassRectorTest.php

@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector;
+
+use Iterator;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+use Symplify\SmartFileSystem\SmartFileInfo;
+
+final class DowngradeReadonlyClassRectorTest extends AbstractRectorTestCase
+{
+    /**
+     * @dataProvider provideData()
+     */
+    public function test(SmartFileInfo $fileInfo): void
+    {
+        $this->doTestFileInfo($fileInfo);
+    }
+
+    /**
+     * @return Iterator<SmartFileInfo>
+     */
+    public function provideData(): Iterator
+    {
+        return $this->yieldFilesFromDirectory(__DIR__ . '/Fixture');
+    }
+
+    public function provideConfigFilePath(): string
+    {
+        return __DIR__ . '/config/configured_rule.php';
+    }
+}

rules-tests/DowngradePhp82/Rector/Class_/DowngradeReadonlyClassRector/Fixture/combine_property_and_property_promotion.php.inc

@@ -0,0 +1,29 @@
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final readonly class CombinePropertyAndPropertyPromotion
+{
+    private string $foo;
+
+    public function __construct(private string $bar)
+    {
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final class CombinePropertyAndPropertyPromotion
+{
+    private readonly string $foo;
+
+    public function __construct(private readonly string $bar)
+    {
+    }
+}
+
+?>

rules-tests/DowngradePhp82/Rector/Class_/DowngradeReadonlyClassRector/Fixture/not_property_promotion.php.inc

@@ -0,0 +1,25 @@
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final readonly class NotPropertyPromotion
+{
+    public function __construct(string $bar)
+    {
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final class NotPropertyPromotion
+{
+    public function __construct(string $bar)
+    {
+    }
+}
+
+?>

rules-tests/DowngradePhp82/Rector/Class_/DowngradeReadonlyClassRector/Fixture/readonly_class.php.inc

@@ -0,0 +1,21 @@
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final readonly class ReadonlyClass
+{
+    public string $foo;
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final class ReadonlyClass
+{
+    public readonly string $foo;
+}
+
+?>

rules-tests/DowngradePhp82/Rector/Class_/DowngradeReadonlyClassRector/Fixture/readonly_class_with_property_promotion.php.inc

@@ -0,0 +1,25 @@
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final readonly class ReadonlyClassWithPropertyPromotion
+{
+    public function __construct(private string $foo)
+    {
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final class ReadonlyClassWithPropertyPromotion
+{
+    public function __construct(private readonly string $foo)
+    {
+    }
+}
+
+?>

rules-tests/DowngradePhp82/Rector/Class_/DowngradeReadonlyClassRector/Fixture/skip_not_readonly.php.inc

@@ -0,0 +1,8 @@
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+class SkipNotReadonly
+{
+    public readonly string $foo;
+}

rules-tests/DowngradePhp82/Rector/Class_/DowngradeReadonlyClassRector/Fixture/static_property.php.inc

@@ -0,0 +1,21 @@
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final readonly class StaticProperty
+{
+    public static string $foo;
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\Fixture;
+
+final class StaticProperty
+{
+    public static string $foo;
+}
+
+?>

rules-tests/DowngradePhp82/Rector/Class_/DowngradeReadonlyClassRector/config/configured_rule.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\Config\RectorConfig;
+use Rector\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector;
+
+return static function (RectorConfig $rectorConfig): void {
+    $rectorConfig->rule(DowngradeReadonlyClassRector::class);
+};

rules/DowngradePhp82/Rector/Class_/DowngradeReadonlyClassRector.php

@@ -0,0 +1,141 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\DowngradePhp82\Rector\Class_;
+
+use PhpParser\Node;
+use PhpParser\Node\Stmt\Class_;
+use PhpParser\Node\Stmt\ClassMethod;
+use Rector\Core\Rector\AbstractRector;
+use Rector\Core\ValueObject\MethodName;
+use Rector\Privatization\NodeManipulator\VisibilityManipulator;
+use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
+use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;
+
+/**
+ * @changelog https://wiki.php.net/rfc/readonly_classes
+ *
+ * @see \Rector\Tests\DowngradePhp82\Rector\Class_\DowngradeReadonlyClassRector\DowngradeReadonlyClassRectorTest
+ */
+final class DowngradeReadonlyClassRector extends AbstractRector
+{
+    public function __construct(private readonly VisibilityManipulator $visibilityManipulator)
+    {
+    }
+
+    /**
+     * @return array<class-string<Node>>
+     */
+    public function getNodeTypes(): array
+    {
+        return [Class_::class];
+    }
+
+    public function getRuleDefinition(): RuleDefinition
+    {
+        return new RuleDefinition(
+            'Remove "readonly" class type, decorate all properties to "readonly"',
+            [
+                new CodeSample(
+                    <<<'CODE_SAMPLE'
+final readonly class SomeClass
+{
+    public string $foo;
+
+    public function __construct()
+    {
+        $this->foo = 'foo';
+    }
+}
+CODE_SAMPLE
+                    ,
+                    <<<'CODE_SAMPLE'
+final readonly class SomeClass
+{
+    public readonly string $foo;
+
+    public function __construct()
+    {
+        $this->foo = 'foo';
+    }
+}
+CODE_SAMPLE
+                ),
+            ]
+        );
+    }
+
+    /**
+     * @param Class_ $node
+     */
+    public function refactor(Node $node): ?Node
+    {
+        if (! $this->visibilityManipulator->isReadonly($node)) {
+            return null;
+        }
+
+        $this->visibilityManipulator->removeReadonly($node);
+        $this->makePropertiesReadonly($node);
+        $this->makePromotedPropertiesReadonly($node);
+
+        return $node;
+    }
+
+    private function makePropertiesReadonly(Class_ $class): void
+    {
+        foreach ($class->getProperties() as $property) {
+            if ($property->isReadonly()) {
+                continue;
+            }
+
+            /**
+             * It technically impossible that readonly class has:
+             *
+             *  - non-typed property
+             *  - static property
+             *
+             * but here to ensure no flip-flop when using direct rule for multiple rules applied
+             */
+            if ($property->type === null) {
+                continue;
+            }
+
+            if ($property->isStatic()) {
+                continue;
+            }
+
+            $this->visibilityManipulator->makeReadonly($property);
+        }
+    }
+
+    private function makePromotedPropertiesReadonly(Class_ $class): void
+    {
+        $classMethod = $class->getMethod(MethodName::CONSTRUCT);
+        if (! $classMethod instanceof ClassMethod) {
+            return;
+        }
+
+        foreach ($classMethod->getParams() as $param) {
+            if ($this->visibilityManipulator->isReadonly($param)) {
+                continue;
+            }
+
+            /**
+             * not property promotion, just param
+             */
+            if ($param->flags === 0) {
+                continue;
+            }
+
+            /**
+             * also not typed, just param
+             */
+            if ($param->type === null) {
+                continue;
+            }
+
+            $this->visibilityManipulator->makeReadonly($param);
+        }
+    }
+}

rules/Privatization/NodeManipulator/VisibilityManipulator.php

@@ -122,12 +122,12 @@ public function makeReadonly(Class_ | Property | Param $node): void
         $this->addVisibilityFlag($node, Visibility::READONLY);
     }
 
-    public function isReadonly(Property | Param $node): bool
+    public function isReadonly(Class_ | Property | Param $node): bool
     {
         return $this->hasVisibility($node, Visibility::READONLY);
     }
 
-    public function removeReadonly(Property | Param $node): void
+    public function removeReadonly(Class_ | Property | Param $node): void
     {
         $this->removeVisibilityFlag($node, Visibility::READONLY);
     }