Simplify narrowToFullyQualifiedOrAliasedObjectType in ObjectTypeSpecifier (#8835)

* simplify narrowToFullyQualifiedOrAliasedObjectType in ObjectTypeSpecifier

* add bench for narrowToFullyQualifiedOrAliasedObjectType

* simplify helper methods in ObjectTypeSpecifier

Author: TomasVotruba

bench/object_type_specifier_narrow_bench.php

@@ -0,0 +1,76 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Benchmark for ObjectTypeSpecifier::narrowToFullyQualifiedOrAliasedObjectType().
+ *
+ * The method is hit once per object-typed phpdoc/name node during type resolution.
+ * The simplification keeps behavior identical; this bench confirms it does not
+ * regress CPU. Three representative inputs are looped, each hitting a different
+ * exit path:
+ *
+ *   - preslash:      leading "\\" short-circuit (top of method)
+ *   - existing:      resolve() uses + reflectionProvider->hasClass() hit -> FullyQualified
+ *   - non-existing:  full fall-through to resolveNamespacedNonExistingObjectType()
+ *
+ * Run on both branches to compare:
+ *   php bench/object_type_specifier_narrow_bench.php
+ *
+ * Reports CPU time (user+sys); wall is noise under concurrent load.
+ */
+
+use PhpParser\Node\Identifier;
+use PHPStan\Type\ObjectType;
+use Rector\DependencyInjection\LazyContainerFactory;
+use Rector\TypeDeclaration\PHPStan\ObjectTypeSpecifier;
+
+require __DIR__ . '/../vendor/autoload.php';
+
+const NODES = 2000;   // narrow() calls per pass
+const REPEAT = 40;    // outer repeats
+
+$rectorConfig = (new LazyContainerFactory())->create();
+$rectorConfig->boot();
+
+/** @var ObjectTypeSpecifier $objectTypeSpecifier */
+$objectTypeSpecifier = $rectorConfig->make(ObjectTypeSpecifier::class);
+
+// node only used in the scope/template branch; scope is null here, so a bare dummy is fine
+$node = new Identifier('x');
+
+$inputs = [
+    new ObjectType('\\' . ObjectType::class), // preslash short-circuit
+    new ObjectType(ObjectType::class),        // existing class -> hasClass hit
+    new ObjectType('No\\Such\\ClassName'),    // non-existing -> full fall-through
+];
+
+$cpuSeconds = static function (): float {
+    $usage = getrusage();
+    return $usage['ru_utime.tv_sec'] + $usage['ru_utime.tv_usec'] / 1_000_000
+        + $usage['ru_stime.tv_sec'] + $usage['ru_stime.tv_usec'] / 1_000_000;
+};
+
+$run = static function () use ($objectTypeSpecifier, $node, $inputs): void {
+    for ($i = 0; $i < NODES; ++$i) {
+        foreach ($inputs as $objectType) {
+            $objectTypeSpecifier->narrowToFullyQualifiedOrAliasedObjectType($node, $objectType, null);
+        }
+    }
+};
+
+// warm up autoloading once, excluded from timing
+$run();
+
+$cpuStart = $cpuSeconds();
+for ($repeat = 0; $repeat < REPEAT; ++$repeat) {
+    $run();
+}
+$cpu = $cpuSeconds() - $cpuStart;
+
+$totalCalls = NODES * count($inputs) * REPEAT;
+
+printf('ObjectTypeSpecifier::narrowToFullyQualifiedOrAliasedObjectType benchmark%s', PHP_EOL);
+printf('  nodes=%d inputs=%d repeat=%d  (%d calls)%s', NODES, count($inputs), REPEAT, $totalCalls, PHP_EOL);
+printf('%s', PHP_EOL);
+printf('  cpu=%.4fs  per-call=%.4fus%s', $cpu, $cpu / $totalCalls * 1_000_000, PHP_EOL);

rules/TypeDeclaration/PHPStan/ObjectTypeSpecifier.php

@@ -44,8 +44,9 @@ public function narrowToFullyQualifiedOrAliasedObjectType(
         Scope|null $scope,
         bool $withPreslash = false
     ): TypeWithClassName|NonExistingObjectType|UnionType|MixedType|TemplateType {
-        $className = ltrim($objectType->getClassName(), '\\');
-        if (str_starts_with($objectType->getClassName(), '\\')) {
+        $rawClassName = $objectType->getClassName();
+        $className = ltrim($rawClassName, '\\');
+        if (str_starts_with($rawClassName, '\\')) {
             return new FullyQualifiedObjectType($className);
         }
 
@@ -87,27 +88,18 @@ public function narrowToFullyQualifiedOrAliasedObjectType(
 
             $classReflection = $scope->getClassReflection();
             if ($classReflection instanceof ClassReflection) {
-                $templateTags = $classReflection->getTemplateTags();
                 $nameScope = $this->nameScopeFactory->createNameScopeFromNodeWithoutTemplateTypes($node);
                 $templateTypeScope = $nameScope->getTemplateTypeScope();
-
-                if (! $templateTypeScope instanceof TemplateTypeScope) {
-                    // invalid type
-                    return $this->resolveNamespacedNonExistingObjectType($namespaceName, $className, $withPreslash);
-                }
-
-                $currentTemplateTag = $templateTags[$className] ?? null;
-                if ($currentTemplateTag === null) {
-                    // invalid type
-                    return $this->resolveNamespacedNonExistingObjectType($namespaceName, $className, $withPreslash);
+                $currentTemplateTag = $classReflection->getTemplateTags()[$className] ?? null;
+
+                if ($templateTypeScope instanceof TemplateTypeScope && $currentTemplateTag !== null) {
+                    return TemplateTypeFactory::create(
+                        $templateTypeScope,
+                        $currentTemplateTag->getName(),
+                        $currentTemplateTag->getBound(),
+                        $currentTemplateTag->getVariance()
+                    );
                 }
-
-                return TemplateTypeFactory::create(
-                    $templateTypeScope,
-                    $currentTemplateTag->getName(),
-                    $currentTemplateTag->getBound(),
-                    $currentTemplateTag->getVariance()
-                );
             }
         }
 
@@ -120,15 +112,7 @@ private function resolveNamespacedNonExistingObjectType(
         string $className,
         bool $withPreslash
     ): NonExistingObjectType {
-        if ($namespacedName === null) {
-            return new NonExistingObjectType($className);
-        }
-
-        if ($withPreslash) {
-            return new NonExistingObjectType($className);
-        }
-
-        if (str_contains($className, '\\')) {
+        if ($namespacedName === null || $withPreslash || str_contains($className, '\\')) {
             return new NonExistingObjectType($className);
         }
 
@@ -153,14 +137,12 @@ private function matchAliasedObjectType(ObjectType $objectType, array $uses): ?A
                     continue;
                 }
 
-                $useName = $prefix . $useUse->name->toString();
                 $alias = $useUse->alias->toString();
                 $fullyQualifiedName = $prefix . $useUse->name->toString();
 
                 $processAliasedObject = $this->processAliasedObject(
                     $alias,
                     $className,
-                    $useName,
                     $fullyQualifiedName
                 );
 
@@ -176,7 +158,6 @@ private function matchAliasedObjectType(ObjectType $objectType, array $uses): ?A
     private function processAliasedObject(
         string $alias,
         string $className,
-        string $useName,
         string $fullyQualifiedName
     ): ?AliasedObjectType {
         // A. is alias in use statement matching this class alias
@@ -185,7 +166,7 @@ private function processAliasedObject(
         }
 
         // B. is aliased classes matching the class name
-        if ($useName === $className) {
+        if ($fullyQualifiedName === $className) {
             return new AliasedObjectType($className, $fullyQualifiedName);
         }