[dead-code] Skip substr casting removal on PHP 7.x, as can return false|string

Author: TomasVotruba

rules-tests/DeadCode/Rector/Cast/RecastingRemovalRector/Fixture/skip_substr.php.inc

@@ -0,0 +1,11 @@
+<?php
+
+namespace Rector\Tests\DeadCode\Rector\Cast\RecastingRemovalRector\FixturePhp74;
+
+final class SkipSubstr
+{
+    public function run(string $value): string
+    {
+        return (string) substr($value, 10, 10);
+    }
+}

rules-tests/DeadCode/Rector/Cast/RecastingRemovalRector/FixturePhp74/skip_substr.php.inc

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DeadCode\Rector\Cast\RecastingRemovalRector;
+
+use Iterator;
+use PHPUnit\Framework\Attributes\DataProvider;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+
+final class RecastingRemovalRectorPhp74Test extends AbstractRectorTestCase
+{
+    #[DataProvider('provideData')]
+    public function test(string $filePath): void
+    {
+        $this->doTestFile($filePath);
+    }
+
+    public static function provideData(): Iterator
+    {
+        return self::yieldFilesFromDirectory(__DIR__ . '/FixturePhp74');
+    }
+
+    public function provideConfigFilePath(): string
+    {
+        return __DIR__ . '/config/configured_rule_php74.php';
+    }
+}

rules-tests/DeadCode/Rector/Cast/RecastingRemovalRector/RecastingRemovalRectorPhp74Test.php

@@ -4,6 +4,8 @@
 
 use Rector\Config\RectorConfig;
 use Rector\DeadCode\Rector\Cast\RecastingRemovalRector;
+use Rector\ValueObject\PhpVersion;
 
 return RectorConfig::configure()
-    ->withRules([RecastingRemovalRector::class]);
+    ->withRules([RecastingRemovalRector::class])
+    ->withPhpVersion(PhpVersion::PHP_80);

rules-tests/DeadCode/Rector/Cast/RecastingRemovalRector/config/configured_rule.php

@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+use Rector\Config\RectorConfig;
+use Rector\DeadCode\Rector\Cast\RecastingRemovalRector;
+use Rector\ValueObject\PhpVersion;
+
+return RectorConfig::configure()
+    ->withRules([RecastingRemovalRector::class])
+    ->withPhpVersion(PhpVersion::PHP_74);

rules-tests/DeadCode/Rector/Cast/RecastingRemovalRector/config/configured_rule_php74.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\ReturnUnionTypeRector\FixtureTrueInUnion;
+
+/**
+ * true|othertype work on >= php 8.2, ref https://3v4l.org/UJqXT
+ */
+final class TrueInUnionStrToUpper
+{
+    public function run($value)
+    {
+        if ($value) {
+            return true;
+        }
+
+        return strtoupper('warning');
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\ReturnUnionTypeRector\FixtureTrueInUnion;
+
+/**
+ * true|othertype work on >= php 8.2, ref https://3v4l.org/UJqXT
+ */
+final class TrueInUnionStrToUpper
+{
+    public function run($value): true|string
+    {
+        if ($value) {
+            return true;
+        }
+
+        return strtoupper('warning');
+    }
+}
+
+?>

rules-tests/TypeDeclaration/Rector/ClassMethod/ReturnUnionTypeRector/FixtureTrueInUnion/true_in_union_strtoupper.php.inc

@@ -46,15 +46,13 @@ public function shouldSkip(File $file, FullyQualifiedObjectType $fullyQualifiedO
         $namespace = strtolower((string) $namespace);
 
         $shortNameLowered = $fullyQualifiedObjectType->getShortNameLowered();
-        /**
-         * on php 7.x, substr() result can return false, so force (string) is needed
-         * @see https://github.com/rectorphp/rector-src/pull/7436
-         */
-        $subClassName = (string) substr(
+
+        $subClassName = substr(
             $fullyQualifiedObjectType->getClassName(),
             0,
             -strlen($fullyQualifiedObjectType->getShortName()) - 1
         );
+
         $fullyQualifiedObjectTypeNamespace = strtolower($subClassName);
 
         foreach ($classLikeNames as $classLikeName) {

rules/CodingStyle/ClassNameImport/ClassNameImportSkipVoter/ClassLikeNameClassNameImportSkipVoter.php

@@ -13,14 +13,12 @@
 use PhpParser\Node\Expr\Cast\Int_;
 use PhpParser\Node\Expr\Cast\Object_;
 use PhpParser\Node\Expr\Cast\String_;
-use PhpParser\Node\Expr\FuncCall;
 use PhpParser\Node\Expr\MethodCall;
 use PhpParser\Node\Expr\StaticCall;
 use PHPStan\Reflection\Php\PhpPropertyReflection;
 use PHPStan\Type\ArrayType;
 use PHPStan\Type\BooleanType;
 use PHPStan\Type\Constant\ConstantArrayType;
-use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\FloatType;
 use PHPStan\Type\IntegerType;
 use PHPStan\Type\MixedType;
@@ -55,7 +53,7 @@ final class RecastingRemovalRector extends AbstractRector
     public function __construct(
         private readonly PropertyFetchAnalyzer $propertyFetchAnalyzer,
         private readonly ReflectionResolver $reflectionResolver,
-        private readonly ExprAnalyzer $exprAnalyzer
+        private readonly ExprAnalyzer $exprAnalyzer,
     ) {
     }
 
@@ -105,13 +103,6 @@ public function refactor(Node $node): ?Node
             return null;
         }
 
-        // substr can return false on php 7.x
-        if ($node->expr instanceof FuncCall
-            && $this->isName($node->expr, 'substr')
-            && ! $node->expr->isFirstClassCallable()) {
-            $nodeType = new UnionType([new StringType(), new ConstantBooleanType(false)]);
-        }
-
         if ($nodeType instanceof ConstantArrayType && $nodeClass === Array_::class) {
             if ($this->shouldSkip($node->expr)) {
                 return null;

rules/DeadCode/Rector/Cast/RecastingRemovalRector.php

@@ -39,6 +39,7 @@
 use PHPStan\Type\NullType;
 use PHPStan\Type\ObjectType;
 use PHPStan\Type\ObjectWithoutClassType;
+use PHPStan\Type\StringType;
 use PHPStan\Type\ThisType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
@@ -55,9 +56,11 @@
 use Rector\NodeTypeResolver\NodeTypeCorrector\AccessoryNonEmptyStringTypeCorrector;
 use Rector\NodeTypeResolver\NodeTypeCorrector\GenericClassStringTypeCorrector;
 use Rector\NodeTypeResolver\PHPStan\ObjectWithoutClassTypeWithParentTypes;
+use Rector\Php\PhpVersionProvider;
 use Rector\StaticTypeMapper\ValueObject\Type\AliasedObjectType;
 use Rector\StaticTypeMapper\ValueObject\Type\ShortenedObjectType;
 use Rector\TypeDeclaration\PHPStan\ObjectTypeSpecifier;
+use Rector\ValueObject\PhpVersion;
 
 final class NodeTypeResolver
 {
@@ -83,6 +86,7 @@ public function __construct(
         private readonly AccessoryNonEmptyArrayTypeCorrector $accessoryNonEmptyArrayTypeCorrector,
         private readonly RenamedClassesDataCollector $renamedClassesDataCollector,
         private readonly NodeNameResolver $nodeNameResolver,
+        private readonly PhpVersionProvider $phpVersionProvider,
         iterable $nodeTypeResolvers
     ) {
         foreach ($nodeTypeResolvers as $nodeTypeResolver) {
@@ -620,6 +624,10 @@ private function resolveNativeTypeWithBuiltinMethodCallFallback(Expr $expr, Scop
                 return $scope->getNativeType($expr);
             }
 
+            if ($this->isSubstrOnPHP74($expr)) {
+                return new UnionType([new StringType(), new ConstantBooleanType(false)]);
+            }
+
             return $scope->getType($expr);
         }
 
@@ -651,4 +659,20 @@ private function isEnumTypeMatch(MethodCall|NullsafeMethodCall $call, ObjectType
 
         return $classReflection->getName() === $objectType->getClassName();
     }
+
+    /**
+     * substr can return false on php 7.x and bellow
+     */
+    private function isSubstrOnPHP74(FuncCall $expr): bool
+    {
+        if ($expr->isFirstClassCallable()) {
+            return false;
+        }
+
+        if (! $this->nodeNameResolver->isName($expr, 'substr')) {
+            return false;
+        }
+
+        return ! $this->phpVersionProvider->isAtLeastPhpVersion(PhpVersion::PHP_80);
+    }
 }