この記事はラクス Advent Calendar 2025の7日目の記事です

composer require rector/rector--dev

vendor/bin/rector

 No"rector.php" config found. Should we generate itforyou?[yes]:>yes[OK] The config is added now. Re-runcommandto make Rectordothe work!

<?phpdeclare(strict_types=1);useRector\Config\RectorConfig;returnRectorConfig::configure()->withPaths([__DIR__.'/src',])// uncomment to reach your current PHP version// ->withPhpSets()->withTypeCoverageLevel(0)->withDeadCodeLevel(0)->withCodeQualityLevel(0);

<?phpdeclare(strict_types=1);namespaceApp;classExample{private$name;private$items;publicfunction__construct($name){$this->name=$name;$this->items=array();}publicfunctiongetName(){return$this->name;}publicfunctionaddItem($item){array_push($this->items,$item);}publicfunctiongetItems(){return$this->items;}publicfunctionhasItems(){if(count($this->items)>0){returntrue;}else{returnfalse;}}publicfunctionfindItem($needle){foreach($this->itemsas$key=>$value){if($value==$needle){return$key;}}returnnull;}privatefunctiondeadCode():void{}}

vendor/bin/rector process--dry-run

 1/1[▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓] 100%1 file with changes===================1) src/Example.php:7---------- begin diff----------@@ @@ class Example{-    private$name;     private$items;-    publicfunction__construct($name)+    publicfunction__construct(private$name){-$this->name=$name;-$this->items= array();+$this->items=[];}----------- end diff-----------Applied rules:* LongArrayToShortArrayRector* ClassPropertyAssignToConstructorPromotionRector[OK] 1 file would have been changed(dry-run) by Rector

vendor/bin/rector src

/** * The rule order matters, as its used in withTypeCoverageLevel() method * Place the safest rules first, follow by more complex ones * * @var array<class-string<RectorInterface>> */publicconstRULES=[// php 7.1, start with closure first, as safestAddClosureVoidReturnTypeWhereNoReturnRector::class,AddFunctionVoidReturnTypeWhereNoReturnRector::class,AddTestsVoidReturnTypeWhereNoReturnRector::class,ReturnIteratorInDataProviderRector::class,ReturnTypeFromMockObjectRector::class,TypedPropertyFromCreateMockAssignRector::class,AddArrowFunctionReturnTypeRector::class,BoolReturnTypeFromBooleanConstReturnsRector::class,ReturnTypeFromStrictNewArrayRector::class,// scalar and array from constantReturnTypeFromStrictConstantReturnRector::class,StringReturnTypeFromStrictScalarReturnsRector::class,...AddClosureParamTypeFromIterableMethodCallRector::class,TypedStaticPropertyInBehatContextRector::class,];

returnRectorConfig::configure()->withPaths([__DIR__.'/src',])->withPhpSets()->withTypeCoverageLevel(100)->withDeadCodeLevel(100)->withCodeQualityLevel(100);

[WARNING] The"->withTypeCoverageLevel()" level contains only 63 rules, but yousetlevel to 100.           You are using the fullsetnow! Time to switch to more efficient"->withPreparedSets(typeDeclarations:           true)".[WARNING] The"->withDeadCodeLevel()" level contains only 55 rules, but yousetlevel to 100.           You are using the fullsetnow! Time to switch to more efficient"->withPreparedSets(deadCode: true)".[WARNING] The"->withCodeQualityLevel()" level contains only 77 rules, but yousetlevel to 100.           You are using the fullsetnow! Time to switch to more efficient"->withPreparedSets(codeQuality: true)".

returnRectorConfig::configure()->withPaths([__DIR__.'/src',])->withPhpSets()->withPreparedSets(typeDeclarations:true,deadCode:true,codeQuality:true,);

  1/1[▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓] 100%1 file with changes===================1) src/Example.php:6---------- begin diff----------@@ @@ class Example{-    private$items;+    private array$items=[];     publicfunction__construct(private$name){-$this->items=[];}     publicfunctiongetName()@@ @@return$this->name;}-    publicfunctionaddItem($item)+    publicfunctionaddItem($item): void{-        array_push($this->items,$item);+$this->items[]=$item;}     publicfunctiongetItems()@@ @@return$this->items;}-    publicfunctionhasItems()+    publicfunctionhasItems(): bool{if(count($this->items)> 0){returntrue;@@ @@}}returnnull;-}--    privatefunctiondeadCode(): void-{}}----------- end diff-----------Applied rules:* InlineConstructorDefaultToPropertyRector* ChangeArrayPushToArrayAssignRector* RemoveUnusedPrivateMethodRector* AddVoidReturnTypeWhereNoReturnRector* BoolReturnTypeFromBooleanConstReturnsRector* TypedPropertyFromAssignsRector[OK] 1 file would have been changed(dry-run) by Rector

 1/1[▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓] 100%1 file with changes===================1) src/Example.php:22---------- begin diff----------@@ @@$this->items[]=$item;}-    publicfunctiongetItems()+    publicfunctiongetItems(): array{return$this->items;}@@ @@}}-    publicfunctionfindItem($needle)+    publicfunctionfindItem($needle): int|string|null{         foreach($this->items as$key=>$value){if($value==$needle){----------- end diff-----------Applied rules:* ReturnTypeFromStrictTypedPropertyRector* ReturnUnionTypeRector[OK] 1 file would have been changed(dry-run) by Rector

<?phpdeclare(strict_types=1);namespaceApp;classExample{// 型ヒントを@varで入れてあげれば良さそう？privatearray$items=[];// $nameの型定義はRectorでは難しそうpublicfunction__construct(private$name){}publicfunctiongetName(){return$this->name;}publicfunctionaddItem($item):void{$this->items[]=$item;}publicfunctiongetItems():array{return$this->items;}// 早期リターンできるpublicfunctionhasItems():bool{if(count($this->items)>0){returntrue;}else{returnfalse;}}publicfunctionfindItem($needle):int|string|null{foreach($this->itemsas$key=>$value){if($value==$needle){return$key;}}returnnull;}}

->withPreparedSets(typeDeclarations:true,deadCode:true,codeQuality:true,earlyReturn:true,codingStyle:true,);

 1/1[▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓] 100%1 file with changes===================1) src/Example.php:29---------- begin diff----------@@ @@     publicfunctionhasItems(): bool{-if(count($this->items)> 0){-returntrue;-}else{-returnfalse;-}+return$this->items!==[];}     publicfunctionfindItem($needle): int|string|null@@ @@return$key;}}+returnnull;}}----------- end diff-----------Applied rules:* SimplifyIfReturnBoolRector* CountArrayToEmptyArrayComparisonRector* NewlineAfterStatementRector* RemoveAlwaysElseRector[OK] 1 file would have been changed(dry-run) by Rector

classExample{private$name;private$items;publicfunction__construct($name){$this->name=$name;$this->items=array();}

-publicfunctiongetName()+publicfunctiongetName():string{return$this->name;}