Draft: hide class-level template types from static members

conf/bleedingEdge.neon

@@ -34,3 +34,4 @@ parameters:
 		unusedVariable: true
 		unusedParameters: true
 		reuseCollectedDataRuleErrors: true
+		disallowClassLevelTemplatesInStaticMethods: true

conf/config.neon

@@ -66,6 +66,7 @@ parameters:
 		unusedVariable: false
 		unusedParameters: false
 		reuseCollectedDataRuleErrors: false
+		disallowClassLevelTemplatesInStaticMethods: false
 	fileExtensions:
 		- php
 	checkAdvancedIsset: false

conf/parametersSchema.neon

@@ -63,6 +63,7 @@ parametersSchema:
 		unusedVariable: bool()
 		unusedParameters: bool()
 		reuseCollectedDataRuleErrors: bool()
+		disallowClassLevelTemplatesInStaticMethods: bool()
 	])
 	fileExtensions: listOf(string())
 	checkAdvancedIsset: bool()

conf/services.neon

@@ -138,6 +138,7 @@ services:
 			phpParser: @stubParser
 			resolvedPhpDocBlockCacheCountMax: %cache.resolvedPhpDocBlockCacheCountMax%
 			nameScopeMapMemoryCacheCountMax: %cache.nameScopeMapMemoryCacheCountMax%
+			disallowClassLevelTemplatesInStaticMethods: %featureToggles.disallowClassLevelTemplatesInStaticMethods%
 		autowired: false
 
 	fileExcluderAnalyse:

src/Type/FileTypeMapper.php

@@ -91,6 +91,8 @@ public function __construct(
 		private int $resolvedPhpDocBlockCacheCountMax,
 		#[AutowiredParameter(ref: '%cache.nameScopeMapMemoryCacheCountMax%')]
 		int $nameScopeMapMemoryCacheCountMax,
+		#[AutowiredParameter(ref: '%featureToggles.disallowClassLevelTemplatesInStaticMethods%')]
+		private bool $disallowClassLevelTemplatesInStaticMethods,
 	)
 	{
 		// 0 kept one entry here rather than meaning "no limit" as it does for the other bounded
@@ -387,7 +389,12 @@ private function getNameScopeMap(string $fileName): array
 		// a map built from the simplified AST of a file outside the analysed paths lacks
 		// the name scopes of classes declared inside function bodies, so it must not be
 		// reused once the file gets analysed, nor the other way around
-		$cacheKey = sprintf('ftm-%s%s', $this->returnsSimplifiedAst($fileName) ? 'simplified-' : '', $fileName);
+		$cacheKey = sprintf(
+			'ftm-%s%s%s',
+			$this->returnsSimplifiedAst($fileName) ? 'simplified-' : '',
+			$this->disallowClassLevelTemplatesInStaticMethods ? 'static-own-scope-' : '',
+			$fileName,
+		);
 		// v6: v5 entries may be poisoned by the turbo comment-loss bug
 		// (https://github.com/phpstan/phpstan/issues/15037) - a parse that
 		// silently dropped every comment cached PHPDoc-less name-scope maps,
@@ -553,13 +560,22 @@ function (Node $node) use ($fileName, $lookForTrait, &$traitFound, $traitMethodA
 				}
 
 				if ($node instanceof Node\Stmt\ClassLike || $node instanceof Node\Stmt\ClassMethod || $node instanceof Node\Stmt\Function_ || $node instanceof Node\PropertyHook) {
+					$parentNameScope = array_last($typeMapStack);
+
+					// static methods exist in their own scope
+					if (
+						$this->disallowClassLevelTemplatesInStaticMethods
+						&& $node instanceof Node\Stmt\ClassMethod
+						&& $node->isStatic()
+					) {
+						$parentNameScope = null;
+					}
+
 					if ($phpDocNode !== null) {
 						if ($node instanceof Node\Stmt\ClassLike) {
 							$typeAliasStack[] = $this->getTypeAliasesMap($phpDocNode);
 						}
 
-						$parentNameScope = array_last($typeMapStack);
-
 						$typeMapStack[] = new IntermediaryNameScope(
 							$namespaceUsesTracker->getNamespaceUses(),
 							$className,
@@ -572,7 +588,6 @@ function (Node $node) use ($fileName, $lookForTrait, &$traitFound, $traitMethodA
 					} elseif ($node instanceof Node\Stmt\ClassLike) {
 						$typeAliasStack[] = [];
 					} else {
-						$parentNameScope = array_last($typeMapStack);
 						$typeMapStack[] = new IntermediaryNameScope(
 							$namespaceUsesTracker->getNamespaceUses(),
 							$className,

tests/PHPStan/Analyser/nsrt/generics.php

@@ -1410,7 +1410,7 @@ class CarFactoryProcessor {
 	 */
 	public function process($class): void {
 		$car = $class::create();
-		assertType(Car::class, $car);
+		assertType(T::class, $car); // @template T is unknown in static method
 	}
 }
 

tests/PHPStan/Analyser/nsrt/static-methods-template-types.php

@@ -0,0 +1,49 @@
+<?php
+
+namespace StaticMethodsTemplateTypes;
+
+use function PHPStan\Testing\assertType;
+
+/**
+ * @template T
+ */
+class Foo
+{
+
+	/**
+	 * @template U
+	 * @param T $t
+	 * @return T
+	 */
+	public static function bar($t)
+	{
+	}
+
+	/**
+	 * @template U
+	 * @param U $u
+	 * @return U
+	 */
+	public static function baz($u)
+	{
+	}
+
+	/**
+	 * @return T
+	 */
+	public static function qux()
+	{
+	}
+
+	public static function doFoo()
+	{
+		assertType('StaticMethodsTemplateTypes\T', self::bar(42));
+		assertType('42', self::baz(42));
+		assertType('StaticMethodsTemplateTypes\T', self::qux());
+	}
+
+}
+
+assertType('StaticMethodsTemplateTypes\T', Foo::bar(42));
+assertType('42', Foo::baz(42));
+assertType('StaticMethodsTemplateTypes\T', Foo::qux());

tests/PHPStan/Rules/Generics/MethodSignatureVarianceRuleTest.php

@@ -186,32 +186,8 @@ public function testRule(): void
 
 		$this->analyse([__DIR__ . '/data/method-signature-variance-constructor.php'], []);
 
-		$this->analyse([__DIR__ . '/data/method-signature-variance-static.php'], [
-			[
-				'Template type X is declared as covariant, but occurs in contravariant position in parameter a of method MethodSignatureVariance\StaticMethod\B::a().',
-				43,
-			],
-			[
-				'Template type X is declared as covariant, but occurs in contravariant position in parameter c of method MethodSignatureVariance\StaticMethod\B::a().',
-				43,
-			],
-			[
-				'Template type X is declared as covariant, but occurs in contravariant position in return type of method MethodSignatureVariance\StaticMethod\B::c().',
-				49,
-			],
-			[
-				'Template type X is declared as contravariant, but occurs in covariant position in parameter b of method MethodSignatureVariance\StaticMethod\C::a().',
-				62,
-			],
-			[
-				'Template type X is declared as contravariant, but occurs in covariant position in return type of method MethodSignatureVariance\StaticMethod\C::b().',
-				65,
-			],
-			[
-				'Template type X is declared as contravariant, but occurs in covariant position in return type of method MethodSignatureVariance\StaticMethod\C::d().',
-				71,
-			],
-		]);
+		// class-level @template X is unknown in static methods
+		$this->analyse([__DIR__ . '/data/method-signature-variance-static.php'], []);
 	}
 
 	public function testBug8880(): void

tests/PHPStan/Rules/Methods/CallStaticMethodsRuleTest.php

@@ -541,7 +541,12 @@ public function testBug6249(): void
 		// discussion https://github.com/phpstan/phpstan/discussions/6249
 		$this->checkThisOnly = false;
 		$this->checkExplicitMixed = true;
-		$this->analyse([__DIR__ . '/data/bug-6249.php'], []);
+		$this->analyse([__DIR__ . '/data/bug-6249.php'], [
+			[
+				'Parameter #1 $iterable of static method Bug6249N3\Cw<(int|string),mixed>::fromIterable() expects iterable<Bug6249N3\TKey, Bug6249N3\T>, Bug6249N2\Eii given.',
+				145,
+			],
+		]);
 	}
 
 	public function testBug5749(): void

tests/PHPStan/Rules/Methods/ExistingClassesInTypehintsRuleTest.php

@@ -153,6 +153,10 @@ public function testExistingClassInTypehint(): void
 				'Template type U of method TestMethodTypehints\TemplateTypeMissingInParameter::doFoo() is not referenced in a parameter.',
 				130,
 			],
+			[
+				'Method TestMethodTypehints\TemplateInStaticMethod::doBar() has invalid return type TestMethodTypehints\T.',
+				163,
+			],
 		]);
 	}
 

tests/PHPStan/Rules/Methods/ReturnTypeRuleTest.php

@@ -1248,7 +1248,29 @@ public function testBug13043(): void
 
 	public function testBug12739(): void
 	{
-		$this->analyse([__DIR__ . '/data/bug-12739.php'], []);
+		// @template TScalar is unknown in static methods
+		$this->analyse([__DIR__ . '/data/bug-12739.php'], [
+			[
+				"Method MyInt::getClassIdentify() should return class-string<ScalarType<TScalar>> but returns 'MyInt'.",
+				20,
+			],
+			[
+				"Method MyString::getClassIdentify() should return class-string<ScalarType<TScalar>> but returns 'MyString'.",
+				29,
+			],
+			[
+				"Method MyLowerString::getClassIdentify() should return class-string<ScalarType<TScalar>> but returns 'MyLowerString'.",
+				38,
+			],
+			[
+				"Method MyUpperString::getClassIdentify() should return class-string<ScalarType<TScalar>> but returns 'MyUpperString'.",
+				47,
+			],
+			[
+				"Method MyClassString::getClassIdentify() should return class-string<ScalarType<TScalar>> but returns 'MyClassString'.",
+				56,
+			],
+		]);
 	}
 
 	public function testBug12928(): void

tests/PHPStan/Rules/Methods/data/bug-6249.php

@@ -106,6 +106,18 @@ public static function fromIterable(iterable $iterable): self
 		return new self($iterable);
 	}
 
+	/**
+	 * @template UKey of array-key
+	 * @template U
+	 * @param iterable<UKey, U> $iterable
+	 *
+	 * @return self<UKey, U>
+	 */
+	public static function fromIterableCorrect(iterable $iterable): self
+	{
+		return new self($iterable);
+	}
+
 	public function count(): int
 	{
 		if (is_array($this->iterable) || $this->iterable instanceof Countable) {
@@ -131,6 +143,7 @@ class Foo
 	public function doFoo()
 	{
 		\Bug6249N3\Cw::fromIterable(new \Bug6249N2\Eii([]));
+		\Bug6249N3\Cw::fromIterableCorrect(new \Bug6249N2\Eii([]));
 	}
 
 }

tests/PHPStan/Rules/Methods/data/typehints.php

@@ -142,3 +142,27 @@ public function doBar(string $class): void
 	}
 
 }
+
+/**
+ * @template T
+ */
+class TemplateInStaticMethod
+{
+
+	/**
+	 * @return T
+	 */
+	public function doFoo()
+	{
+
+	}
+
+	/**
+	 * @return T
+	 */
+	public static function doBar()
+	{
+
+	}
+
+}

tests/PHPStan/Type/FileTypeMapperTest.php

@@ -303,6 +303,7 @@ private function createFileTypeMapper(CacheStorage $storage): FileTypeMapper
 			$container->getByType(FileContentHasher::class),
 			2048,
 			128,
+			false,
 		);
 	}