[8.x] Fix replacing required :input with null on PHP 8.1

[dshoreman]

Fixes an issue where missing fields in the data being validated will cause a deprecation warning when formatting the message, because str_replace() expects a string but gets null:

framework/src/Illuminate/Validation/Concerns/FormatsMessages.php

Lines 309 to 311 in a7ec58e

	if (is_scalar($actualValue) || is_null($actualValue)) {
	$message = str_replace(':input', $this->getDisplayableValue($attribute, $actualValue), $message);
	}

---

This is already covered but requires PHP > 8.0 to trigger:

framework/tests/Validation/ValidationValidatorTest.php

Lines 110 to 118 in 354c57b

	public function testValidateThrowsOnFail()
	{
	$this->expectException(ValidationException::class);
	$trans = $this->getIlluminateArrayTranslator();
	$v = new Validator($trans, ['foo' => 'bar'], ['baz' => 'required']);
	$v->validate();
	}

framework/tests/Validation/ValidationValidatorTest.php

Lines 881 to 885 in 354c57b

	public function testValidateRequired()
	{
	$trans = $this->getIlluminateArrayTranslator();
	$v = new Validator($trans, [], ['name' => 'Required']);
	$this->assertFalse($v->passes());

Full Stacktrace

 [2021-03-06 15:20:07] testing.ERROR: str_replace(): Passing null to parameter #2 ($replace) of type array|string is deprecated {"userId":35,"exception":"[object] (ErrorException(code: 0): str_replace(): Passing null to parameter #2 ($replace) of type array|string is deprecated at ./vendor/laravel/framework/src/Illuminate/Validation/Concerns/FormatsMessages.php:310)
[stacktrace]
#0 [internal function]: Illuminate\\Foundation\\Bootstrap\\HandleExceptions->handleError()
#1 ./vendor/laravel/framework/src/Illuminate/Validation/Concerns/FormatsMessages.php(310): str_replace()
#2 ./vendor/laravel/framework/src/Illuminate/Validation/Concerns/FormatsMessages.php(219): Illuminate\\Validation\\Validator->replaceInputPlaceholder()
#3 ./vendor/laravel/framework/src/Illuminate/Validation/Validator.php(814): Illuminate\\Validation\\Validator->makeReplacements()
#4 ./vendor/laravel/framework/src/Illuminate/Validation/Validator.php(566): Illuminate\\Validation\\Validator->addFailure()
#5 ./vendor/laravel/framework/src/Illuminate/Validation/Validator.php(388): Illuminate\\Validation\\Validator->validateAttribute()
#6 ./vendor/laravel/framework/src/Illuminate/Validation/Validator.php(419): Illuminate\\Validation\\Validator->passes()
#7 ./vendor/laravel/framework/src/Illuminate/Validation/ValidatesWhenResolvedTrait.php(25): Illuminate\\Validation\\Validator->fails()
#8 ./vendor/laravel/framework/src/Illuminate/Foundation/Providers/FormRequestServiceProvider.php(30): Illuminate\\Foundation\\Http\\FormRequest->validateResolved()
#9 ./vendor/laravel/framework/src/Illuminate/Container/Container.php(1219): Illuminate\\Foundation\\Providers\\FormRequestServiceProvider->Illuminate\\Foundation\\Providers\\{closure}()
#10 ./vendor/laravel/framework/src/Illuminate/Container/Container.php(1183): Illuminate\\Container\\Container->fireCallbackArray()
#11 ./vendor/laravel/framework/src/Illuminate/Container/Container.php(1168): Illuminate\\Container\\Container->fireAfterResolvingCallbacks()
#12 ./vendor/laravel/framework/src/Illuminate/Container/Container.php(732): Illuminate\\Container\\Container->fireResolvingCallbacks()
#13 ./vendor/laravel/framework/src/Illuminate/Foundation/Application.php(841): Illuminate\\Container\\Container->resolve()
#14 ./vendor/laravel/framework/src/Illuminate/Container/Container.php(651): Illuminate\\Foundation\\Application->resolve()
#15 ./vendor/laravel/framework/src/Illuminate/Foundation/Application.php(826): Illuminate\\Container\\Container->make()
#16 ./vendor/laravel/framework/src/Illuminate/Routing/RouteDependencyResolverTrait.php(79): Illuminate\\Foundation\\Application->make()
#17 ./vendor/laravel/framework/src/Illuminate/Routing/RouteDependencyResolverTrait.php(48): Illuminate\\Routing\\ControllerDispatcher->transformDependency()
#18 ./vendor/laravel/framework/src/Illuminate/Routing/RouteDependencyResolverTrait.php(28): Illuminate\\Routing\\ControllerDispatcher->resolveMethodDependencies()
#19 ./vendor/laravel/framework/src/Illuminate/Routing/ControllerDispatcher.php(41): Illuminate\\Routing\\ControllerDispatcher->resolveClassMethodDependencies()
#20 ./vendor/laravel/framework/src/Illuminate/Routing/Route.php(254): Illuminate\\Routing\\ControllerDispatcher->dispatch()
#21 ./vendor/laravel/framework/src/Illuminate/Routing/Route.php(197): Illuminate\\Routing\\Route->runController()
#22 ./vendor/laravel/framework/src/Illuminate/Routing/Router.php(693): Illuminate\\Routing\\Route->run()
#23 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(128): Illuminate\\Routing\\Router->Illuminate\\Routing\\{closure}()
#24 ./vendor/laravel/framework/src/Illuminate/Routing/Middleware/SubstituteBindings.php(50): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#25 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Illuminate\\Routing\\Middleware\\SubstituteBindings->handle()
#26 ./vendor/laravel/framework/src/Illuminate/Routing/Middleware/ThrottleRequests.php(127): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#27 ./vendor/laravel/framework/src/Illuminate/Routing/Middleware/ThrottleRequests.php(103): Illuminate\\Routing\\Middleware\\ThrottleRequests->handleRequest()
#28 ./vendor/laravel/framework/src/Illuminate/Routing/Middleware/ThrottleRequests.php(55): Illuminate\\Routing\\Middleware\\ThrottleRequests->handleRequestUsingNamedLimiter()
#29 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Illuminate\\Routing\\Middleware\\ThrottleRequests->handle()
#30 ./vendor/laravel/framework/src/Illuminate/Auth/Middleware/Authenticate.php(44): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#31 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Illuminate\\Auth\\Middleware\\Authenticate->handle()
#32 ./vendor/laravel/sanctum/src/Http/Middleware/EnsureFrontendRequestsAreStateful.php(33): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#33 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(128): Laravel\\Sanctum\\Http\\Middleware\\EnsureFrontendRequestsAreStateful->Laravel\\Sanctum\\Http\\Middleware\\{closure}()
#34 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(103): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#35 ./vendor/laravel/sanctum/src/Http/Middleware/EnsureFrontendRequestsAreStateful.php(34): Illuminate\\Pipeline\\Pipeline->then()
#36 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Laravel\\Sanctum\\Http\\Middleware\\EnsureFrontendRequestsAreStateful->handle()
#37 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(103): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#38 ./vendor/laravel/framework/src/Illuminate/Routing/Router.php(695): Illuminate\\Pipeline\\Pipeline->then()
#39 ./vendor/laravel/framework/src/Illuminate/Routing/Router.php(670): Illuminate\\Routing\\Router->runRouteWithinStack()
#40 ./vendor/laravel/framework/src/Illuminate/Routing/Router.php(636): Illuminate\\Routing\\Router->runRoute()
#41 ./vendor/laravel/framework/src/Illuminate/Routing/Router.php(625): Illuminate\\Routing\\Router->dispatchToRoute()
#42 ./vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(166): Illuminate\\Routing\\Router->dispatch()
#43 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(128): Illuminate\\Foundation\\Http\\Kernel->Illuminate\\Foundation\\Http\\{closure}()
#44 ./vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/TransformsRequest.php(21): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#45 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest->handle()
#46 ./vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/TransformsRequest.php(21): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#47 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Illuminate\\Foundation\\Http\\Middleware\\TransformsRequest->handle()
#48 ./vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/ValidatePostSize.php(27): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#49 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Illuminate\\Foundation\\Http\\Middleware\\ValidatePostSize->handle()
#50 ./vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/PreventRequestsDuringMaintenance.php(86): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#51 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Illuminate\\Foundation\\Http\\Middleware\\PreventRequestsDuringMaintenance->handle()
#52 ./vendor/fruitcake/laravel-cors/src/HandleCors.php(57): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#53 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Fruitcake\\Cors\\HandleCors->handle()
#54 ./vendor/fideloper/proxy/src/TrustProxies.php(57): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#55 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(167): Fideloper\\Proxy\\TrustProxies->handle()
#56 ./vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(103): Illuminate\\Pipeline\\Pipeline->Illuminate\\Pipeline\\{closure}()
#57 ./vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(141): Illuminate\\Pipeline\\Pipeline->then()
#58 ./vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(110): Illuminate\\Foundation\\Http\\Kernel->sendRequestThroughRouter()
#59 ./vendor/laravel/framework/src/Illuminate/Foundation/Testing/Concerns/MakesHttpRequests.php(508): Illuminate\\Foundation\\Http\\Kernel->handle()
#60 ./vendor/laravel/framework/src/Illuminate/Foundation/Testing/Concerns/MakesHttpRequests.php(474): Illuminate\\Foundation\\Testing\\TestCase->call()
#61 ./vendor/laravel/framework/src/Illuminate/Foundation/Testing/Concerns/MakesHttpRequests.php(333): Illuminate\\Foundation\\Testing\\TestCase->json()
#62 ./tests/Feature/Api/Projects/CreateProjectTest.php(119): Illuminate\\Foundation\\Testing\\TestCase->postJson()
#63 ./vendor/phpunit/phpunit/src/Framework/TestCase.php(1526): Tests\\Feature\\Api\\Projects\\CreateProjectTest->cannot_create_project_without_name()
#64 ./vendor/phpunit/phpunit/src/Framework/TestCase.php(1132): PHPUnit\\Framework\\TestCase->runTest()
#65 ./vendor/phpunit/phpunit/src/Framework/TestResult.php(722): PHPUnit\\Framework\\TestCase->runBare()
#66 ./vendor/phpunit/phpunit/src/Framework/TestCase.php(884): PHPUnit\\Framework\\TestResult->run()
#67 ./vendor/phpunit/phpunit/src/Framework/TestSuite.php(677): PHPUnit\\Framework\\TestCase->run()
#68 ./vendor/phpunit/phpunit/src/Framework/TestSuite.php(677): PHPUnit\\Framework\\TestSuite->run()
#69 ./vendor/phpunit/phpunit/src/Framework/TestSuite.php(677): PHPUnit\\Framework\\TestSuite->run()
#70 ./vendor/phpunit/phpunit/src/TextUI/TestRunner.php(667): PHPUnit\\Framework\\TestSuite->run()
#71 ./vendor/phpunit/phpunit/src/TextUI/Command.php(142): PHPUnit\\TextUI\\TestRunner->run()
#72 ./vendor/phpunit/phpunit/src/TextUI/Command.php(95): PHPUnit\\TextUI\\Command->run()
#73 ./vendor/phpunit/phpunit/phpunit(61): PHPUnit\\TextUI\\Command::main()
#74 {main}
"}