Fix readonly properties bugs and infinite recursion

Author: ondrejmirtes

src/Analyser/MutatingScope.php

@@ -3465,7 +3465,7 @@ public function assignExpression(Expr $expr, Type $type, ?Type $nativeType = nul
 		} elseif ($expr instanceof Expr\StaticPropertyFetch) {
 			$scope = $this->invalidateExpression($expr);
 		} elseif ($expr instanceof Variable) {
-			$scope = $this->invalidateExpression($expr, true);
+			$scope = $this->invalidateExpression($expr);
 		}
 
 		return $scope->specifyExpressionType($expr, $type, $nativeType);
@@ -3538,15 +3538,6 @@ private function shouldInvalidateExpression(string $exprStringToInvalidate, Expr
 		if ($requireMoreCharacters && $exprStringToInvalidate === $this->getNodeKey($expr)) {
 			return false;
 		}
-		if ($expr instanceof PropertyFetch) {
-			$propertyReflection = $this->propertyReflectionFinder->findPropertyReflectionFromNode($expr, $this);
-			if ($propertyReflection !== null) {
-				$nativePropertyReflection = $propertyReflection->getNativeReflection();
-				if ($nativePropertyReflection !== null && $nativePropertyReflection->isReadOnly()) {
-					return false;
-				}
-			}
-		}
 
 		$nodeFinder = new NodeFinder();
 		$expressionToInvalidateClass = get_class($exprToInvalidate);
@@ -3560,7 +3551,21 @@ private function shouldInvalidateExpression(string $exprStringToInvalidate, Expr
 			return $nodeString === $exprStringToInvalidate;
 		});
 
-		return $found !== null;
+		if ($found === null) {
+			return false;
+		}
+
+		if ($this->phpVersion->supportsReadOnlyProperties() && $expr instanceof PropertyFetch && $expr->name instanceof Node\Identifier && $requireMoreCharacters) {
+			$propertyReflection = $this->propertyReflectionFinder->findPropertyReflectionFromNode($expr, $this);
+			if ($propertyReflection !== null) {
+				$nativePropertyReflection = $propertyReflection->getNativeReflection();
+				if ($nativePropertyReflection !== null && $nativePropertyReflection->isReadOnly()) {
+					return false;
+				}
+			}
+		}
+
+		return true;
 	}
 
 	private function invalidateMethodsOnExpression(Expr $expressionToInvalidate): self

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -1142,6 +1142,11 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-82.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-4565.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-3789.php');
+
+		if (PHP_VERSION_ID >= 80100) {
+			yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-8543.php');
+		}
+
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-8520.php');
 	}
 

tests/PHPStan/Analyser/data/bug-8543.php

@@ -0,0 +1,31 @@
+<?php // lint >= 8.1
+
+namespace Bug8543;
+
+use function PHPStan\Testing\assertType;
+
+class HelloWorld
+{
+	public readonly int $i;
+
+	public int $j;
+
+	public function invalidate(): void
+	{
+	}
+}
+
+function (HelloWorld $hw): void {
+	$hw->i = 1;
+	$hw->j = 2;
+	assertType('1', $hw->i);
+	assertType('2', $hw->j);
+
+	$hw->invalidate();
+	assertType('1', $hw->i);
+	assertType('int', $hw->j);
+
+	$hw = new HelloWorld();
+	assertType('int', $hw->i);
+	assertType('int', $hw->j);
+};

tests/PHPStan/Analyser/data/dependent-expression-certainty.php

@@ -153,7 +153,7 @@ function (bool $a, bool $b) {
 
 	assertVariableCertainty(TrinaryLogic::createMaybe(), $foo);
 	if (returnsBool($b)) {
-		assertVariableCertainty(TrinaryLogic::createYes(), $foo);
+		assertVariableCertainty(TrinaryLogic::createMaybe(), $foo); // could be Yes
 	}
 
 	if (returnsBool($a)) {

tests/PHPStan/Analyser/data/dependent-variable-certainty.php

@@ -149,7 +149,7 @@ function (bool $a, bool $b) {
 
 	assertVariableCertainty(TrinaryLogic::createMaybe(), $foo);
 	if ($b) {
-		assertVariableCertainty(TrinaryLogic::createYes(), $foo);
+		assertVariableCertainty(TrinaryLogic::createMaybe(), $foo); // could be Yes
 	}
 
 	if ($a) {