Lint exercises before running

src/Exception/CouldNotRunException.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshop\Exception;
+
+use PhpSchool\PhpWorkshop\Result\FailureInterface;
+
+class CouldNotRunException extends RuntimeException
+{
+    private FailureInterface $failure;
+
+    public function __construct(FailureInterface $failure)
+    {
+        $this->failure = $failure;
+        parent::__construct('Could not run exercise');
+    }
+
+    public static function fromFailure(FailureInterface $failure): self
+    {
+        return new self($failure);
+    }
+
+    public function getFailure(): FailureInterface
+    {
+        return $this->failure;
+    }
+}

src/ExerciseDispatcher.php

@@ -6,6 +6,7 @@
 
 use PhpSchool\PhpWorkshop\Check\CheckRepository;
 use PhpSchool\PhpWorkshop\Check\ListenableCheckInterface;
+use PhpSchool\PhpWorkshop\Check\PhpLintCheck;
 use PhpSchool\PhpWorkshop\Check\SimpleCheckInterface;
 use PhpSchool\PhpWorkshop\Event\EventDispatcher;
 use PhpSchool\PhpWorkshop\Event\ExerciseRunnerEvent;
@@ -16,6 +17,8 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\RunnerManager;
 use PhpSchool\PhpWorkshop\Input\Input;
 use PhpSchool\PhpWorkshop\Output\OutputInterface;
+use PhpSchool\PhpWorkshop\Result\FailureInterface;
+use PhpSchool\PhpWorkshop\Exception\CouldNotRunException;
 
 /**
  * This class is used to verify/run a student's solution to an exercise. It routes to the correct
@@ -179,6 +182,15 @@ public function verify(ExerciseInterface $exercise, Input $input): ResultAggrega
     public function run(ExerciseInterface $exercise, Input $input, OutputInterface $output): bool
     {
         $exercise->configure($this);
+
+        /** @var PhpLintCheck $lint */
+        $lint = $this->checkRepository->getByClass(PhpLintCheck::class);
+        $result = $lint->check($exercise, $input);
+
+        if ($result instanceof FailureInterface) {
+            throw CouldNotRunException::fromFailure($result);
+        }
+
         $this->eventDispatcher->dispatch(new ExerciseRunnerEvent('run.start', $exercise, $input));
 
         try {

test/ExerciseDispatcherTest.php

@@ -5,6 +5,7 @@
 use PhpSchool\PhpWorkshop\Check\CheckInterface;
 use PhpSchool\PhpWorkshop\Check\CheckRepository;
 use PhpSchool\PhpWorkshop\Check\ListenableCheckInterface;
+use PhpSchool\PhpWorkshop\Check\PhpLintCheck;
 use PhpSchool\PhpWorkshop\Check\SimpleCheckInterface;
 use PhpSchool\PhpWorkshop\Event\EventDispatcher;
 use PhpSchool\PhpWorkshop\Event\EventInterface;
@@ -538,7 +539,7 @@ public function testRun(): void
             $runnerManager,
             new ResultAggregator(),
             new EventDispatcher(new ResultAggregator()),
-            new CheckRepository()
+            new CheckRepository([new PhpLintCheck()])
         );
 
         $this->assertTrue($exerciseDispatcher->run($exercise, $input, $output));