Support for @mixin

Author: ondrejmirtes

conf/config.level2.neon

@@ -33,6 +33,12 @@ rules:
 	- PHPStan\Rules\PhpDoc\WrongVariableNameInVarTagRule
 
 services:
+	-
+		class: PHPStan\Rules\Classes\MixinRule
+		arguments:
+			checkClassCaseSensitivity: %checkClassCaseSensitivity%
+		tags:
+			- phpstan.rules.rule
 	-
 		class: PHPStan\Rules\Functions\CallCallablesRule
 		arguments:

conf/config.neon

@@ -476,6 +476,16 @@ services:
 	-
 		class: PHPStan\Reflection\BetterReflection\SourceLocator\OptimizedSingleFileSourceLocatorRepository
 
+	-
+		class: PHPStan\Reflection\Mixin\MixinMethodsClassReflectionExtension
+		tags:
+			- phpstan.broker.methodsClassReflectionExtension
+
+	-
+		class: PHPStan\Reflection\Mixin\MixinPropertiesClassReflectionExtension
+		tags:
+			- phpstan.broker.propertiesClassReflectionExtension
+
 	-
 		class: PHPStan\Reflection\Php\PhpClassReflectionExtension
 		arguments:

src/PhpDoc/PhpDocNodeResolver.php

@@ -8,6 +8,7 @@
 use PHPStan\PhpDoc\Tag\ImplementsTag;
 use PHPStan\PhpDoc\Tag\MethodTag;
 use PHPStan\PhpDoc\Tag\MethodTagParameter;
+use PHPStan\PhpDoc\Tag\MixinTag;
 use PHPStan\PhpDoc\Tag\ParamTag;
 use PHPStan\PhpDoc\Tag\PropertyTag;
 use PHPStan\PhpDoc\Tag\ReturnTag;
@@ -16,6 +17,7 @@
 use PHPStan\PhpDoc\Tag\UsesTag;
 use PHPStan\PhpDoc\Tag\VarTag;
 use PHPStan\PhpDocParser\Ast\ConstExpr\ConstExprNullNode;
+use PHPStan\PhpDocParser\Ast\PhpDoc\MixinTagValueNode;
 use PHPStan\PhpDocParser\Ast\PhpDoc\PhpDocNode;
 use PHPStan\PhpDocParser\Ast\PhpDoc\TemplateTagValueNode;
 use PHPStan\PhpDocParser\Ast\PhpDoc\ThrowsTagValueNode;
@@ -339,6 +341,20 @@ public function resolveThrowsTags(PhpDocNode $phpDocNode, NameScope $nameScope):
 		return new ThrowsTag(TypeCombinator::union(...$types));
 	}
 
+	/**
+	 * @param PhpDocNode $phpDocNode
+	 * @param NameScope $nameScope
+	 * @return array<MixinTag>
+	 */
+	public function resolveMixinTags(PhpDocNode $phpDocNode, NameScope $nameScope): array
+	{
+		return array_map(function (MixinTagValueNode $mixinTagValueNode) use ($nameScope): MixinTag {
+			return new MixinTag(
+				$this->typeNodeResolver->resolve($mixinTagValueNode->type, $nameScope)
+			);
+		}, $phpDocNode->getMixinTagValues());
+	}
+
 	public function resolveDeprecatedTag(PhpDocNode $phpDocNode, NameScope $nameScope): ?\PHPStan\PhpDoc\Tag\DeprecatedTag
 	{
 		foreach ($phpDocNode->getDeprecatedTagValues() as $deprecatedTagValue) {

src/PhpDoc/ResolvedPhpDocBlock.php

@@ -3,6 +3,7 @@
 namespace PHPStan\PhpDoc;
 
 use PHPStan\Analyser\NameScope;
+use PHPStan\PhpDoc\Tag\MixinTag;
 use PHPStan\PhpDocParser\Ast\PhpDoc\PhpDocNode;
 use PHPStan\Type\Generic\TemplateTypeMap;
 
@@ -57,6 +58,9 @@ class ResolvedPhpDocBlock
 	/** @var \PHPStan\PhpDoc\Tag\ThrowsTag|false|null */
 	private $throwsTag = false;
 
+	/** @var array<MixinTag>|false */
+	private $mixinTags = false;
+
 	/** @var \PHPStan\PhpDoc\Tag\DeprecatedTag|false|null */
 	private $deprecatedTag = false;
 
@@ -314,6 +318,21 @@ public function getThrowsTag(): ?\PHPStan\PhpDoc\Tag\ThrowsTag
 		return $this->throwsTag;
 	}
 
+	/**
+	 * @return array<MixinTag>
+	 */
+	public function getMixinTags(): array
+	{
+		if ($this->mixinTags === false) {
+			$this->mixinTags = $this->phpDocNodeResolver->resolveMixinTags(
+				$this->phpDocNode,
+				$this->nameScope
+			);
+		}
+
+		return $this->mixinTags;
+	}
+
 	public function getDeprecatedTag(): ?\PHPStan\PhpDoc\Tag\DeprecatedTag
 	{
 		if ($this->deprecatedTag === false) {

src/PhpDoc/Tag/MixinTag.php

@@ -0,0 +1,34 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\PhpDoc\Tag;
+
+use PHPStan\Type\Type;
+
+class MixinTag
+{
+
+	/** @var \PHPStan\Type\Type */
+	private $type;
+
+	public function __construct(Type $type)
+	{
+		$this->type = $type;
+	}
+
+	public function getType(): Type
+	{
+		return $this->type;
+	}
+
+	/**
+	 * @param mixed[] $properties
+	 * @return self
+	 */
+	public static function __set_state(array $properties): self
+	{
+		return new self(
+			$properties['type']
+		);
+	}
+
+}

src/Reflection/ClassReflection.php

@@ -5,6 +5,7 @@
 use PHPStan\PhpDoc\ResolvedPhpDocBlock;
 use PHPStan\PhpDoc\Tag\ExtendsTag;
 use PHPStan\PhpDoc\Tag\ImplementsTag;
+use PHPStan\PhpDoc\Tag\MixinTag;
 use PHPStan\PhpDoc\Tag\TemplateTag;
 use PHPStan\Reflection\Php\PhpClassReflectionExtension;
 use PHPStan\Reflection\Php\PhpPropertyReflection;
@@ -941,4 +942,38 @@ private function isValidAncestorType(Type $type, array $ancestorClasses): bool
 		return in_array($reflection->getName(), $ancestorClasses, true);
 	}
 
+	/**
+	 * @return array<MixinTag>
+	 */
+	public function getMixinTags(): array
+	{
+		$resolvedPhpDoc = $this->getResolvedPhpDoc();
+		if ($resolvedPhpDoc === null) {
+			return [];
+		}
+
+		return $resolvedPhpDoc->getMixinTags();
+	}
+
+	/**
+	 * @return array<Type>
+	 */
+	public function getResolvedMixinTypes(): array
+	{
+		$types = [];
+		foreach ($this->getMixinTags() as $mixinTag) {
+			if (!$this->isGeneric()) {
+				$types[] = $mixinTag->getType();
+				continue;
+			}
+
+			$types[] = TemplateTypeHelper::resolveTemplateTypes(
+				$mixinTag->getType(),
+				$this->getActiveTemplateTypeMap()
+			);
+		}
+
+		return $types;
+	}
+
 }

src/Reflection/Mixin/MixinMethodsClassReflectionExtension.php

@@ -0,0 +1,51 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Reflection\Mixin;
+
+use PHPStan\Analyser\OutOfClassScope;
+use PHPStan\Reflection\ClassReflection;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Reflection\MethodsClassReflectionExtension;
+
+class MixinMethodsClassReflectionExtension implements MethodsClassReflectionExtension
+{
+
+	public function hasMethod(ClassReflection $classReflection, string $methodName): bool
+	{
+		return $this->findMethod($classReflection, $methodName) !== null;
+	}
+
+	public function getMethod(ClassReflection $classReflection, string $methodName): MethodReflection
+	{
+		$method = $this->findMethod($classReflection, $methodName);
+		if ($method === null) {
+			throw new \PHPStan\ShouldNotHappenException();
+		}
+
+		return $method;
+	}
+
+	private function findMethod(ClassReflection $classReflection, string $methodName): ?MethodReflection
+	{
+		$mixinTypes = $classReflection->getResolvedMixinTypes();
+		foreach ($mixinTypes as $type) {
+			if (!$type->hasMethod($methodName)->yes()) {
+				continue;
+			}
+
+			return $type->getMethod($methodName, new OutOfClassScope());
+		}
+
+		foreach ($classReflection->getParents() as $parentClass) {
+			$method = $this->findMethod($parentClass, $methodName);
+			if ($method === null) {
+				continue;
+			}
+
+			return $method;
+		}
+
+		return null;
+	}
+
+}

src/Reflection/Mixin/MixinPropertiesClassReflectionExtension.php

@@ -0,0 +1,51 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Reflection\Mixin;
+
+use PHPStan\Analyser\OutOfClassScope;
+use PHPStan\Reflection\ClassReflection;
+use PHPStan\Reflection\PropertiesClassReflectionExtension;
+use PHPStan\Reflection\PropertyReflection;
+
+class MixinPropertiesClassReflectionExtension implements PropertiesClassReflectionExtension
+{
+
+	public function hasProperty(ClassReflection $classReflection, string $propertyName): bool
+	{
+		return $this->findProperty($classReflection, $propertyName) !== null;
+	}
+
+	public function getProperty(ClassReflection $classReflection, string $propertyName): PropertyReflection
+	{
+		$property = $this->findProperty($classReflection, $propertyName);
+		if ($property === null) {
+			throw new \PHPStan\ShouldNotHappenException();
+		}
+
+		return $property;
+	}
+
+	private function findProperty(ClassReflection $classReflection, string $propertyName): ?PropertyReflection
+	{
+		$mixinTypes = $classReflection->getResolvedMixinTypes();
+		foreach ($mixinTypes as $type) {
+			if (!$type->hasProperty($propertyName)->yes()) {
+				continue;
+			}
+
+			return $type->getProperty($propertyName, new OutOfClassScope());
+		}
+
+		foreach ($classReflection->getParents() as $parentClass) {
+			$property = $this->findProperty($parentClass, $propertyName);
+			if ($property === null) {
+				continue;
+			}
+
+			return $property;
+		}
+
+		return null;
+	}
+
+}