Add more code coverage

tests/CronBuilderTest.php

@@ -78,6 +78,32 @@ public function it_merges(): void
         self::assertSame($expected, CronBuilder::merge($existingCrontab, self::getCronBuilder()));
     }
 
+    /**
+     * @test
+     *
+     * @dataProvider invalidJobsFileProvider
+     */
+    public function it_throws_exception_when_jobs_file_is_invalid(string $jobsFile): void
+    {
+        $this->expectException(\InvalidArgumentException::class);
+
+        (new CronBuilder())
+            ->addFile(__DIR__ . '/cronjobs_invalid/' . $jobsFile)
+            ->build()
+        ;
+    }
+
+    /**
+     * @return \Generator<array-key, array{string}>
+     */
+    public function invalidJobsFileProvider(): \Generator
+    {
+        yield ['jobs1.php'];
+        yield ['jobs2.php'];
+        yield ['jobs3.php'];
+        yield ['jobs4.php'];
+    }
+
     private static function getCronBuilder(): CronBuilder
     {
         $cronBuilder = new CronBuilder();

tests/cronjobs_invalid/jobs1.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+use Setono\CronBuilder\CronJob;
+
+return [
+    new CronJob('0 0 * * *', '/usr/bin/php {{ release_path }}/{{ release_number }}/send-report.php {{ args|join(" ") }}', 'Run every day at midnight'),
+];

tests/cronjobs_invalid/jobs2.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+use Setono\CronBuilder\Context;
+use Setono\CronBuilder\CronJob;
+
+return static function (Context $context): string {
+    return 'not an iterable';
+};

tests/cronjobs_invalid/jobs3.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+use Setono\CronBuilder\Context;
+use Setono\CronBuilder\CronJob;
+
+return static function (Context $context): iterable {
+    yield 'not an object';
+};

tests/cronjobs_invalid/jobs4.php

@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+use Setono\CronBuilder\Context;
+use Setono\CronBuilder\CronJob;
+
+return static function (Context $context): iterable {
+    yield new \stdClass();
+};