Check whether method parameter has typehint

Author: adaamz

src/Rules/Methods/MissingMethodParameterTypehintRule.php

@@ -0,0 +1,66 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Methods;
+
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Reflection\ParameterReflection;
+use PHPStan\Type\MixedType;
+
+final class MissingMethodParameterTypehintRule implements \PHPStan\Rules\Rule
+{
+
+	/**
+	 * @return string Class implementing \PhpParser\Node
+	 */
+	public function getNodeType(): string
+	{
+		return \PhpParser\Node\Stmt\ClassMethod::class;
+	}
+
+	/**
+	 * @param \PhpParser\Node\Stmt\ClassMethod $node
+	 * @param \PHPStan\Analyser\Scope $scope
+	 *
+	 * @return string[] errors
+	 */
+	public function processNode(Node $node, Scope $scope): array
+	{
+		if (!$scope->isInClass()) {
+			throw new \PHPStan\ShouldNotHappenException();
+		}
+
+		$methodReflection = $scope->getClassReflection()->getNativeMethod($node->name);
+
+		$messages = [];
+
+		foreach ($methodReflection->getParameters() as $parameterReflection) {
+			$message = $this->checkMethodParameter($methodReflection, $parameterReflection);
+			if ($message === null) {
+				continue;
+			}
+
+			$messages[] = $message;
+		}
+
+		return $messages;
+	}
+
+	private function checkMethodParameter(MethodReflection $methodReflection, ParameterReflection $parameterReflection): ?string
+	{
+		$parameterType = $parameterReflection->getType();
+
+		if ($parameterType instanceof MixedType && !$parameterType->isExplicitMixed()) {
+			return sprintf(
+				'Method %s::%s() has parameter $%s with no typehint specified',
+				$methodReflection->getDeclaringClass()->getName(),
+				$methodReflection->getName(),
+				$parameterReflection->getName()
+			);
+		}
+
+		return null;
+	}
+
+}

tests/Rules/Methods/MissingMethodParameterTypehintRuleTest.php

@@ -0,0 +1,39 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Methods;
+
+class MissingMethodParameterTypehintRuleTest extends \PHPStan\Testing\RuleTestCase
+{
+
+	protected function getRule(): \PHPStan\Rules\Rule
+	{
+		return new MissingMethodParameterTypehintRule();
+	}
+
+	public function testRule(): void
+	{
+		$this->analyse([__DIR__ . '/data/missing-method-parameter-typehint.php'], [
+			[
+				'Method MissingMethodParameterTypehint\FooInterface::getFoo() has parameter $p1 with no typehint specified',
+				8,
+			],
+			[
+				'Method MissingMethodParameterTypehint\FooParent::getBar() has parameter $p2 with no typehint specified',
+				15,
+			],
+			[
+				'Method MissingMethodParameterTypehint\Foo::getFoo() has parameter $p1 with no typehint specified',
+				25,
+			],
+			[
+				'Method MissingMethodParameterTypehint\Foo::getBar() has parameter $p2 with no typehint specified',
+				33,
+			],
+			[
+				'Method MissingMethodParameterTypehint\Foo::getBaz() has parameter $p3 with no typehint specified',
+				42,
+			],
+		]);
+	}
+
+}

tests/Rules/Methods/data/missing-method-parameter-typehint.php

@@ -0,0 +1,55 @@
+<?php
+
+namespace MissingMethodParameterTypehint;
+
+interface FooInterface
+{
+
+    public function getFoo($p1): void;
+
+}
+
+class FooParent
+{
+
+    public function getBar($p2)
+    {
+
+    }
+
+}
+
+class Foo extends FooParent implements FooInterface
+{
+
+    public function getFoo($p1): void
+    {
+
+    }
+
+    /**
+     * @param $p2
+     */
+    public function getBar($p2)
+    {
+
+    }
+
+    /**
+     * @param $p3
+     * @param int $p4
+     */
+    public function getBaz($p3, $p4): bool
+    {
+        return false;
+    }
+
+    /**
+     * @param mixed $p5
+     */
+    public function getFooBar($p5): bool
+    {
+        return false;
+    }
+
+}