Use $varType->isNull()->maybe() instead of TypeCombinator::containsNull()

Address review feedback: cache $varType->isNull() in a variable to avoid
computing it twice, and use ->maybe() instead of TypeCombinator::containsNull()
for the nullable check.

Update throw-points test: doesntThrow() returns mixed which can be null,
so ?-> may short-circuit and variables assigned in the method name/arguments
should be "maybe defined", not "yes defined".

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: 2 people

src/Analyser/ExprHandler/NullsafeMethodCallHandler.php

@@ -81,10 +81,11 @@ public function processExpr(NodeScopeResolver $nodeScopeResolver, Stmt $stmt, Ex
 		);
 		$scope = $this->nonNullabilityHelper->revertNonNullability($exprResult->getScope(), $nonNullabilityResult->getSpecifiedExpressions());
 
-		if ($varType->isNull()->yes()) {
+		$varIsNull = $varType->isNull();
+		if ($varIsNull->yes()) {
 			// Arguments are never evaluated when the var is always null.
 			$scope = $scopeBeforeNullsafe;
-		} elseif (TypeCombinator::containsNull($varType)) {
+		} elseif ($varIsNull->maybe()) {
 			// Arguments might not be evaluated (short-circuit).
 			// Merge with the original scope so variables assigned in arguments become "maybe defined".
 			$scope = $scope->mergeWith($scopeBeforeNullsafe);

tests/PHPStan/Analyser/nsrt/throw-points/php8/null-safe-method-call.php

@@ -42,8 +42,9 @@ function () {
 	try {
 		doesntThrow()?->{$foo = 1}($bar = 2);
 	} finally {
-		assertVariableCertainty(TrinaryLogic::createYes(), $foo);
-		assertVariableCertainty(TrinaryLogic::createYes(), $bar);
+		// doesntThrow() returns mixed which can be null, so ?-> may short-circuit
+		assertVariableCertainty(TrinaryLogic::createMaybe(), $foo);
+		assertVariableCertainty(TrinaryLogic::createMaybe(), $bar);
 	}
 };