phpstan · ondrejmirtes · Apr 27, 2022 · Apr 27, 2022 · Apr 27, 2022 · Apr 27, 2022
diff --git a/conf/bleedingEdge.neon b/conf/bleedingEdge.neon
@@ -11,3 +11,4 @@ parameters:
 		disableRuntimeReflectionProvider: true
 		illegalConstructorMethodCall: true
 		disableCheckMissingIterableValueType: true
+		strictUnnecessaryNullsafePropertyFetch: true
diff --git a/conf/config.level4.neon b/conf/config.level4.neon
@@ -15,7 +15,6 @@ rules:
 	- PHPStan\Rules\Methods\CallToMethodStatementWithoutSideEffectsRule
 	- PHPStan\Rules\Methods\CallToStaticMethodStatementWithoutSideEffectsRule
 	- PHPStan\Rules\Methods\NullsafeMethodCallRule
-	- PHPStan\Rules\Properties\NullsafePropertyFetchRule
 	- PHPStan\Rules\TooWideTypehints\TooWideArrowFunctionReturnTypehintRule
 	- PHPStan\Rules\TooWideTypehints\TooWideClosureReturnTypehintRule
 	- PHPStan\Rules\TooWideTypehints\TooWideFunctionReturnTypehintRule
@@ -162,3 +161,10 @@ services:
 			checkProtectedAndPublicMethods: %checkTooWideReturnTypesInProtectedAndPublicMethods%
 		tags:
 			- phpstan.rules.rule
+
+	-
+		class: PHPStan\Rules\Properties\NullsafePropertyFetchRule
+		arguments:
+			strictUnnecessaryNullsafePropertyFetch: %featureToggles.strictUnnecessaryNullsafePropertyFetch%
+		tags:
+			- phpstan.rules.rule
diff --git a/conf/config.neon b/conf/config.neon
@@ -35,6 +35,7 @@ parameters:
 		nodeConnectingVisitorRule: false
 		illegalConstructorMethodCall: false
 		disableCheckMissingIterableValueType: false
+		strictUnnecessaryNullsafePropertyFetch: false
 	fileExtensions:
 		- php
 	checkAdvancedIsset: false
@@ -226,6 +227,7 @@ parametersSchema:
 		nodeConnectingVisitorRule: bool(),
 		illegalConstructorMethodCall: bool(),
 		disableCheckMissingIterableValueType: bool(),
+		strictUnnecessaryNullsafePropertyFetch: bool(),
 	])
 	fileExtensions: listOf(string())
 	checkAdvancedIsset: bool()

diff --git a/src/Rules/Properties/NullsafePropertyFetchRule.php b/src/Rules/Properties/NullsafePropertyFetchRule.php
@@ -16,6 +16,10 @@
 class NullsafePropertyFetchRule implements Rule
 {
 
+	public function __construct(private bool $strictUnnecessaryNullsafePropertyFetch)
+	{
+	}
+
 	public function getNodeType(): string
 	{
 		return Node\Expr\NullsafePropertyFetch::class;
@@ -33,6 +37,16 @@ public function processNode(Node $node, Scope $scope): array
 			return [];
 		}
 
+		if ($scope->isUndefinedExpressionAllowed($node)) {
+			if ($this->strictUnnecessaryNullsafePropertyFetch) {
+				return [
+					RuleErrorBuilder::message('Using nullsafe property access on left side of ?? / in isset / in empty is unnecessary. Use -> instead.')->build(),
+				];
+			}
+
+			return [];
+		}
+
 		return [
 			RuleErrorBuilder::message(sprintf('Using nullsafe property access on non-nullable type %s. Use -> instead.', $calledOnType->describe(VerbosityLevel::typeOnly())))->build(),
 		];

diff --git a/tests/PHPStan/Rules/Properties/NullsafePropertyFetchRuleTest.php b/tests/PHPStan/Rules/Properties/NullsafePropertyFetchRuleTest.php
@@ -12,13 +12,17 @@
 class NullsafePropertyFetchRuleTest extends RuleTestCase
 {
 
+	private bool $strictUnnecessaryNullsafePropertyFetch;
+
 	protected function getRule(): Rule
 	{
-		return new NullsafePropertyFetchRule();
+		return new NullsafePropertyFetchRule($this->strictUnnecessaryNullsafePropertyFetch);
 	}
 
 	public function testRule(): void
 	{
+		$this->strictUnnecessaryNullsafePropertyFetch = false;
+
 		if (PHP_VERSION_ID < 80000 && !self::$useStaticReflectionProvider) {
 			$this->markTestSkipped('Test requires PHP 8.0.');
 		}
@@ -33,11 +37,48 @@ public function testRule(): void
 
 	public function testBug6020(): void
 	{
+		$this->strictUnnecessaryNullsafePropertyFetch = false;
+
 		if (PHP_VERSION_ID < 80000 && !self::$useStaticReflectionProvider) {
 			$this->markTestSkipped('Test requires PHP 8.0.');
 		}
 
 		$this->analyse([__DIR__ . '/data/bug-6020.php'], []);
 	}
 
+	public function testBug7109(): void
+	{
+		$this->strictUnnecessaryNullsafePropertyFetch = false;
+
+		if (PHP_VERSION_ID < 80000) {
+			$this->markTestSkipped('Test requires PHP 8.0.');
+		}
+
+		$this->analyse([__DIR__ . '/data/bug-7109.php'], []);
+	}
+
+	public function testBug7109Strict(): void
+	{
+		$this->strictUnnecessaryNullsafePropertyFetch = true;
+
+		if (PHP_VERSION_ID < 80000) {
+			$this->markTestSkipped('Test requires PHP 8.0.');
+		}
+
+		$this->analyse([__DIR__ . '/data/bug-7109.php'], [
+			[
+				'Using nullsafe property access on left side of ?? / in isset / in empty is unnecessary. Use -> instead.',
+				15,
+			],
+			[
+				'Using nullsafe property access on left side of ?? / in isset / in empty is unnecessary. Use -> instead.',
+				16,
+			],
+			[
+				'Using nullsafe property access on left side of ?? / in isset / in empty is unnecessary. Use -> instead.',
+				17,
+			],
+		]);
+	}
+
 }
diff --git a/tests/PHPStan/Rules/Properties/data/bug-7109.php b/tests/PHPStan/Rules/Properties/data/bug-7109.php
@@ -0,0 +1,19 @@
+<?php declare(strict_types = 1); // lint >= 8.0
+
+class HelloWorld
+{
+	public int $aaa = 5;
+	/**
+	 * @return HelloWorld|null
+	 */
+	public function get(): ?HelloWorld
+	{
+		return rand() ? $this : null;
+	}
+	public function sayHello(): void
+	{
+		$this->get()?->aaa ?? 6;
+		isset($this->get()?->aaa) ?: 6;
+		empty($this->get()?->aaa) ?: 6;
+	}
+}