Report unused protected when class is final

Author: VincentLanglet

src/Rules/DeadCode/UnusedPrivateConstantRule.php

@@ -35,11 +35,12 @@ public function processNode(Node $node, Scope $scope): array
 		}
 
 		$classReflection = $node->getClassReflection();
+		$isClassFinal = $classReflection->isFinalByKeyword();
 		$classType = new ObjectType($classReflection->getName(), classReflection: $classReflection);
 
 		$constants = [];
 		foreach ($node->getConstants() as $constant) {
-			if (!$constant->isPrivate()) {
+			if ($constant->isPublic() || ($constant->isProtected() && !$isClassFinal)) {
 				continue;
 			}
 

src/Rules/DeadCode/UnusedPrivateMethodRule.php

@@ -40,6 +40,7 @@ public function processNode(Node $node, Scope $scope): array
 			return [];
 		}
 		$classReflection = $node->getClassReflection();
+		$isClassFinal = $classReflection->isFinalByKeyword();
 		$classType = new ObjectType($classReflection->getName(), classReflection: $classReflection);
 		$constructor = null;
 		if ($classReflection->hasConstructor()) {
@@ -48,13 +49,15 @@ public function processNode(Node $node, Scope $scope): array
 
 		$methods = [];
 		foreach ($node->getMethods() as $method) {
-			if (!$method->getNode()->isPrivate()) {
+			$methodNode = $method->getNode();
+			if ($methodNode->isPublic() || ($methodNode->isProtected() && !$isClassFinal)) {
 				continue;
 			}
 			if ($method->isDeclaredInTrait()) {
 				continue;
 			}
-			$methodName = $method->getNode()->name->toString();
+
+			$methodName = $methodNode->name->toString();
 			if ($constructor !== null && $constructor->getName() === $methodName) {
 				continue;
 			}

src/Rules/DeadCode/UnusedPrivatePropertyRule.php

@@ -56,10 +56,11 @@ public function processNode(Node $node, Scope $scope): array
 			return [];
 		}
 		$classReflection = $node->getClassReflection();
+		$isClassFinal = $classReflection->isFinalByKeyword();
 		$classType = new ObjectType($classReflection->getName(), classReflection: $classReflection);
 		$properties = [];
 		foreach ($node->getProperties() as $property) {
-			if (!$property->isPrivate()) {
+			if ($property->isPublic() || ($property->isProtected() && !$isClassFinal)) {
 				continue;
 			}
 			if ($property->isDeclaredInTrait()) {

tests/PHPStan/Rules/DeadCode/UnusedPrivateConstantRuleTest.php

@@ -49,6 +49,22 @@ public function testRule(): void
 		]);
 	}
 
+	public function testProtected(): void
+	{
+		$this->analyse([__DIR__ . '/data/unused-protected-constant.php'], [
+			[
+				'Constant UnusedProtectedConstant\Bar::BAR_CONST is unused.',
+				26,
+				'See: https://phpstan.org/developing-extensions/always-used-class-constants',
+			],
+			[
+				'Constant UnusedProtectedConstant\Bar::BAZ_CONST is unused.',
+				28,
+				'See: https://phpstan.org/developing-extensions/always-used-class-constants',
+			],
+		]);
+	}
+
 	public function testBug5651(): void
 	{
 		$this->analyse([__DIR__ . '/data/bug-5651.php'], []);

tests/PHPStan/Rules/DeadCode/UnusedPrivateMethodRuleTest.php

@@ -62,6 +62,20 @@ public function testRule(): void
 		]);
 	}
 
+	public function testProtected(): void
+	{
+		$this->analyse([__DIR__ . '/data/unused-protected-method.php'], [
+			[
+				'Method UnusedProtectedMethod\Bar::unused1() is unused.',
+				30,
+			],
+			[
+				'Method UnusedProtectedMethod\Bar::unused2() is unused.',
+				35,
+			],
+		]);
+	}
+
 	public function testBug3630(): void
 	{
 		$this->analyse([__DIR__ . '/data/bug-3630.php'], []);

tests/PHPStan/Rules/DeadCode/UnusedPrivatePropertyRuleTest.php

@@ -186,6 +186,24 @@ public function testTrait(): void
 		$this->analyse([__DIR__ . '/data/private-property-trait.php'], []);
 	}
 
+	public function testProtected(): void
+	{
+		$this->alwaysWrittenTags = [];
+		$this->alwaysReadTags = [];
+		$this->analyse([__DIR__ . '/data/unused-protected-property.php'], [
+			[
+				'Property UnusedProtectedProperty\Bar::$bar is unused.',
+				31,
+				'See: https://phpstan.org/developing-extensions/always-read-written-properties',
+			],
+			[
+				'Property UnusedProtectedProperty\Bar::$baz is unused.',
+				33,
+				'See: https://phpstan.org/developing-extensions/always-read-written-properties',
+			],
+		]);
+	}
+
 	public function testBug3636(): void
 	{
 		$this->alwaysWrittenTags = [];

tests/PHPStan/Rules/DeadCode/data/unused-protected-constant.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace UnusedProtectedConstant;
+
+class Foo
+{
+
+	protected const FOO_CONST = 1;
+
+	protected const BAR_CONST = 2;
+
+	final protected const BAZ_CONST = 2;
+
+	public function doFoo()
+	{
+		echo self::FOO_CONST;
+	}
+
+}
+
+final class Bar
+{
+
+	protected const FOO_CONST = 1;
+
+	protected const BAR_CONST = 2;
+
+	final protected const BAZ_CONST = 2;
+
+	public function doFoo()
+	{
+		echo self::FOO_CONST;
+	}
+
+}

tests/PHPStan/Rules/DeadCode/data/unused-protected-method.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace UnusedProtectedMethod;
+
+class Foo
+{
+	protected function used1()
+	{
+	}
+
+	protected function unused1()
+	{
+		$this->used1();
+	}
+
+	final protected function unused2()
+	{
+		$this->used1();
+	}
+
+}
+
+final class Bar
+{
+
+	protected function used1()
+	{
+	}
+
+	protected function unused1()
+	{
+		$this->used1();
+	}
+
+	final protected function unused2()
+	{
+		$this->used1();
+	}
+
+}

tests/PHPStan/Rules/DeadCode/data/unused-protected-property.php

@@ -0,0 +1,45 @@
+<?php // lint >= 8.4
+
+namespace UnusedProtectedProperty;
+
+class Foo
+{
+
+	protected $foo;
+
+	protected string $bar;
+
+	final protected string $baz;
+
+	public function __construct()
+	{
+		$this->foo = 1;
+	}
+
+	public function getFoo()
+	{
+		return $this->foo;
+	}
+
+}
+
+final class Bar
+{
+
+	protected $foo;
+
+	protected string $bar;
+
+	final protected string $baz;
+
+	public function __construct()
+	{
+		$this->foo = 1;
+	}
+
+	public function getFoo()
+	{
+		return $this->foo;
+	}
+
+}