Fix interact method inference

Author: VincentLanglet

src/Type/Symfony/InputInterfaceGetArgumentDynamicReturnTypeExtension.php

@@ -57,6 +57,7 @@ public function getTypeFromMethodCall(MethodReflection $methodReflection, Method
 		$argName = $argStrings[0]->getValue();
 
 		$argTypes = [];
+		$canBeNullInInteract = false;
 		foreach ($this->consoleApplicationResolver->findCommands($classReflection) as $command) {
 			try {
 				$command->mergeApplicationDefinition();
@@ -70,6 +71,8 @@ public function getTypeFromMethodCall(MethodReflection $methodReflection, Method
 					$argType = new StringType();
 					if (!$argument->isRequired()) {
 						$argType = TypeCombinator::union($argType, $scope->getTypeFromValue($argument->getDefault()));
+					} else {
+						$canBeNullInInteract = true;
 					}
 				}
 				$argTypes[] = $argType;
@@ -78,16 +81,21 @@ public function getTypeFromMethodCall(MethodReflection $methodReflection, Method
 			}
 		}
 
+		if (count($argTypes) === 0) {
+			return null;
+		}
+
 		$method = $scope->getFunction();
 		if (
-			$method instanceof MethodReflection
+			$canBeNullInInteract
+			&& $method instanceof MethodReflection
 			&& $method->getName() === 'interact'
 			&& in_array('Symfony\Component\Console\Command\Command', $method->getDeclaringClass()->getParentClassesNames(), true)
 		) {
 			$argTypes[] = new NullType();
 		}
 
-		return count($argTypes) > 0 ? TypeCombinator::union(...$argTypes) : null;
+		return TypeCombinator::union(...$argTypes);
 	}
 
 }

tests/Type/Symfony/data/ExampleBaseCommand.php

@@ -3,6 +3,7 @@
 namespace PHPStan\Type\Symfony;
 
 use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Output\OutputInterface;
 use function PHPStan\Testing\assertType;
@@ -14,16 +15,18 @@ protected function configure(): void
 	{
 		parent::configure();
 
+		$this->addArgument('required', InputArgument::REQUIRED);
 		$this->addArgument('base');
 	}
 
 	protected function interact(InputInterface $input, OutputInterface $output): int
 	{
 		assertType('string|null', $input->getArgument('base'));
-		assertType('string|null', $input->getArgument('aaa'));
-		assertType('string|null', $input->getArgument('bbb'));
-		assertType('array<int, string>|string|null', $input->getArgument('diff'));
-		assertType('array<int, string>|null', $input->getArgument('arr'));
+		assertType('string', $input->getArgument('aaa'));
+		assertType('string', $input->getArgument('bbb'));
+		assertType('string|null', $input->getArgument('required'));
+		assertType('array<int, string>|string', $input->getArgument('diff'));
+		assertType('array<int, string>', $input->getArgument('arr'));
 		assertType('string|null', $input->getArgument('both'));
 		assertType('Symfony\Component\Console\Helper\QuestionHelper', $this->getHelper('question'));
 	}
@@ -33,6 +36,7 @@ protected function execute(InputInterface $input, OutputInterface $output): int
 		assertType('string|null', $input->getArgument('base'));
 		assertType('string', $input->getArgument('aaa'));
 		assertType('string', $input->getArgument('bbb'));
+		assertType('string', $input->getArgument('required'));
 		assertType('array<int, string>|string', $input->getArgument('diff'));
 		assertType('array<int, string>', $input->getArgument('arr'));
 		assertType('string|null', $input->getArgument('both'));