Support MockBuilder

Author: ondrejmirtes

extension.neon

@@ -10,3 +10,11 @@ services:
 		class: PHPStan\Type\PHPUnit\CreateMockDynamicReturnTypeExtension
 		tags:
 			- phpstan.broker.dynamicMethodReturnTypeExtension
+	-
+		class: PHPStan\Type\PHPUnit\GetMockBuilderDynamicReturnTypeExtension
+		tags:
+			- phpstan.broker.dynamicMethodReturnTypeExtension
+	-
+		class: PHPStan\Type\PHPUnit\MockBuilderDynamicReturnTypeExtension
+		tags:
+			- phpstan.broker.dynamicMethodReturnTypeExtension

src/Type/PHPUnit/GetMockBuilderDynamicReturnTypeExtension.php

@@ -0,0 +1,50 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\PHPUnit;
+
+use PhpParser\Node\Expr\MethodCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Type\Type;
+
+class GetMockBuilderDynamicReturnTypeExtension implements \PHPStan\Type\DynamicMethodReturnTypeExtension
+{
+
+	public static function getClass(): string
+	{
+		return \PHPUnit\Framework\TestCase::class;
+	}
+
+	public function isMethodSupported(MethodReflection $methodReflection): bool
+	{
+		return $methodReflection->getName() === 'getMockBuilder';
+	}
+
+	public function getTypeFromMethodCall(MethodReflection $methodReflection, MethodCall $methodCall, Scope $scope): Type
+	{
+		if (count($methodCall->args) === 0) {
+			return $methodReflection->getReturnType();
+		}
+		$arg = $methodCall->args[0]->value;
+		if (!($arg instanceof \PhpParser\Node\Expr\ClassConstFetch)) {
+			return $methodReflection->getReturnType();
+		}
+
+		$class = $arg->class;
+		if (!($class instanceof \PhpParser\Node\Name)) {
+			return $methodReflection->getReturnType();
+		}
+
+		$class = (string) $class;
+		if ($class === 'static') {
+			return $methodReflection->getReturnType();
+		}
+
+		if ($class === 'self') {
+			$class = $scope->getClassReflection()->getName();
+		}
+
+		return new MockBuilderType($class);
+	}
+
+}

src/Type/PHPUnit/MockBuilderDynamicReturnTypeExtension.php

@@ -0,0 +1,49 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\PHPUnit;
+
+use PhpParser\Node\Expr\MethodCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Type\ObjectType;
+use PHPStan\Type\Type;
+use PHPStan\Type\TypeCombinator;
+
+class MockBuilderDynamicReturnTypeExtension implements \PHPStan\Type\DynamicMethodReturnTypeExtension
+{
+
+	public static function getClass(): string
+	{
+		return \PHPUnit_Framework_MockObject_MockBuilder::class;
+	}
+
+	public function isMethodSupported(MethodReflection $methodReflection): bool
+	{
+		return true;
+	}
+
+	public function getTypeFromMethodCall(MethodReflection $methodReflection, MethodCall $methodCall, Scope $scope): Type
+	{
+		$calledOnType = $scope->getType($methodCall->var);
+		if (!in_array(
+			$methodReflection->getName(),
+			[
+				'getMock',
+				'getMockForAbstractClass',
+			],
+			true
+		)) {
+			return $calledOnType;
+		}
+
+		if (!$calledOnType instanceof MockBuilderType) {
+			return $methodReflection->getReturnType();
+		}
+
+		$mockedClassType = new ObjectType($calledOnType->getMockedClass());
+		$mockType = new ObjectType(\PHPUnit_Framework_MockObject_MockObject::class);
+
+		return TypeCombinator::intersect($mockedClassType, $mockType);
+	}
+
+}

src/Type/PHPUnit/MockBuilderType.php

@@ -0,0 +1,29 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\PHPUnit;
+
+class MockBuilderType extends \PHPStan\Type\ObjectType
+{
+
+	/**
+	 * @var string
+	 */
+	private $mockedClass;
+
+	public function __construct(string $mockedClass)
+	{
+		parent::__construct(\PHPUnit_Framework_MockObject_MockBuilder::class);
+		$this->mockedClass = $mockedClass;
+	}
+
+	public function getMockedClass(): string
+	{
+		return $this->mockedClass;
+	}
+
+	public function describe(): string
+	{
+		return sprintf('%s<%s>', parent::describe(), $this->mockedClass);
+	}
+
+}