Fix phpstan/phpstan#13735: Don't forget $this property types after static method call

- Static methods cannot modify instance properties on $this, so property
  fetch expressions on $this should not be invalidated by static calls
- Added fromStaticCall parameter to invalidateExpression/shouldInvalidateExpression
- Added isThisInstancePropertyAccessChain helper to detect $this->prop chains
- Method calls on $this (e.g. $this->getFoo()) are still invalidated since
  the method body could reference static state
- parent::__construct() correctly still invalidates $this properties since
  the method is not static

Author: github-actions[bot]

src/Analyser/ExprHandler/StaticCallHandler.php

@@ -217,7 +217,7 @@ public function processExpr(NodeScopeResolver $nodeScopeResolver, Stmt $stmt, Ex
 			&& $scope->isInClass()
 			&& $scope->getClassReflection()->is($methodReflection->getDeclaringClass()->getName())
 		) {
-			$scope = $scope->invalidateExpression(new Variable('this'), true, $methodReflection->getDeclaringClass());
+			$scope = $scope->invalidateExpression(new Variable('this'), true, $methodReflection->getDeclaringClass(), $methodReflection->isStatic());
 		} elseif (
 			$methodReflection !== null
 			&& $this->rememberPossiblyImpureFunctionValues

src/Analyser/MutatingScope.php

@@ -2857,7 +2857,7 @@ public function assignInitializedProperty(Type $fetchedOnType, string $propertyN
 		return $this->assignExpression(new PropertyInitializationExpr($propertyName), new MixedType(), new MixedType());
 	}
 
-	public function invalidateExpression(Expr $expressionToInvalidate, bool $requireMoreCharacters = false, ?ClassReflection $invalidatingClass = null): self
+	public function invalidateExpression(Expr $expressionToInvalidate, bool $requireMoreCharacters = false, ?ClassReflection $invalidatingClass = null, bool $fromStaticCall = false): self
 	{
 		$expressionTypes = $this->expressionTypes;
 		$nativeExpressionTypes = $this->nativeExpressionTypes;
@@ -2866,7 +2866,7 @@ public function invalidateExpression(Expr $expressionToInvalidate, bool $require
 
 		foreach ($expressionTypes as $exprString => $exprTypeHolder) {
 			$exprExpr = $exprTypeHolder->getExpr();
-			if (!$this->shouldInvalidateExpression($exprStringToInvalidate, $expressionToInvalidate, $exprExpr, $exprString, $requireMoreCharacters, $invalidatingClass)) {
+			if (!$this->shouldInvalidateExpression($exprStringToInvalidate, $expressionToInvalidate, $exprExpr, $exprString, $requireMoreCharacters, $invalidatingClass, $fromStaticCall)) {
 				continue;
 			}
 
@@ -2881,7 +2881,7 @@ public function invalidateExpression(Expr $expressionToInvalidate, bool $require
 				continue;
 			}
 			$firstExpr = $holders[array_key_first($holders)]->getTypeHolder()->getExpr();
-			if ($this->shouldInvalidateExpression($exprStringToInvalidate, $expressionToInvalidate, $firstExpr, $this->getNodeKey($firstExpr), false, $invalidatingClass)) {
+			if ($this->shouldInvalidateExpression($exprStringToInvalidate, $expressionToInvalidate, $firstExpr, $this->getNodeKey($firstExpr), false, $invalidatingClass, $fromStaticCall)) {
 				$invalidated = true;
 				continue;
 			}
@@ -2890,7 +2890,7 @@ public function invalidateExpression(Expr $expressionToInvalidate, bool $require
 				$shouldKeep = true;
 				$conditionalTypeHolders = $holder->getConditionExpressionTypeHolders();
 				foreach ($conditionalTypeHolders as $conditionalTypeHolderExprString => $conditionalTypeHolder) {
-					if ($this->shouldInvalidateExpression($exprStringToInvalidate, $expressionToInvalidate, $conditionalTypeHolder->getExpr(), $conditionalTypeHolderExprString, false, $invalidatingClass)) {
+					if ($this->shouldInvalidateExpression($exprStringToInvalidate, $expressionToInvalidate, $conditionalTypeHolder->getExpr(), $conditionalTypeHolderExprString, false, $invalidatingClass, $fromStaticCall)) {
 						$invalidated = true;
 						$shouldKeep = false;
 						break;
@@ -2944,7 +2944,7 @@ private function getIntertwinedRefRootVariableName(Expr $expr): ?string
 		return null;
 	}
 
-	private function shouldInvalidateExpression(string $exprStringToInvalidate, Expr $exprToInvalidate, Expr $expr, string $exprString, bool $requireMoreCharacters = false, ?ClassReflection $invalidatingClass = null): bool
+	private function shouldInvalidateExpression(string $exprStringToInvalidate, Expr $exprToInvalidate, Expr $expr, string $exprString, bool $requireMoreCharacters = false, ?ClassReflection $invalidatingClass = null, bool $fromStaticCall = false): bool
 	{
 		if (
 			$expr instanceof IntertwinedVariableByReferenceWithExpr
@@ -3011,6 +3011,13 @@ private function shouldInvalidateExpression(string $exprStringToInvalidate, Expr
 			return false;
 		}
 
+		if (
+			$fromStaticCall
+			&& $this->isThisInstancePropertyAccessChain($expr)
+		) {
+			return false;
+		}
+
 		return true;
 	}
 
@@ -3030,6 +3037,21 @@ private function isPrivatePropertyOfDifferentClass(Expr $expr, ClassReflection $
 		return false;
 	}
 
+	private function isThisInstancePropertyAccessChain(Expr $expr): bool
+	{
+		if ($expr instanceof Variable && is_string($expr->name) && $expr->name === 'this') {
+			return true;
+		}
+		if ($expr instanceof PropertyFetch) {
+			return $this->isThisInstancePropertyAccessChain($expr->var);
+		}
+		if ($expr instanceof Expr\ArrayDimFetch) {
+			return $this->isThisInstancePropertyAccessChain($expr->var);
+		}
+
+		return false;
+	}
+
 	private function invalidateMethodsOnExpression(Expr $expressionToInvalidate): self
 	{
 		$exprStringToInvalidate = null;

tests/PHPStan/Analyser/nsrt/bug-13735.php

@@ -0,0 +1,31 @@
+<?php // lint >= 8.0
+
+declare(strict_types = 1);
+
+namespace Bug13735;
+
+use function PHPStan\Testing\assertType;
+
+class Bug13735Test
+{
+	private ?Foo $foo = null;
+
+	public function testFoo(): void
+	{
+		$this->foo = new Foo();
+		assertType('Bug13735\Foo', $this->foo);
+		self::assertTrue(true);
+		assertType('Bug13735\Foo', $this->foo);
+	}
+
+	public static function assertTrue(mixed $condition, string $message = ''): void
+	{
+
+	}
+}
+
+class Foo {
+	public function doSomething(): bool {
+		return true;
+	}
+}