adds unit test for checking file existence in repo

Author: Michele Orselli

test/unit/FilesExistTest.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace SendGrid\Test;
+
+class FilesExistTest extends \PHPUnit_Framework_TestCase
+{
+    public function testFileArePresentInRepo()
+    {
+        $this->assertFileExists('./.gitignore');
+        $this->assertFileExists('./.env_sample');
+        $this->assertFileExists('./.travis.yml');
+        $this->assertFileExists('./.codeclimate.yml');
+        $this->assertFileExists('./CHANGELOG.md');
+        $this->assertFileExists('./CODE_OF_CONDUCT.md');
+        $this->assertFileExists('./CONTRIBUTING.md');
+        $this->assertFileExists('./.github/ISSUE_TEMPLATE');
+        $this->assertFileExists('./LICENSE.md');
+        $this->assertFileExists('./.github/PULL_REQUEST_TEMPLATE');
+        $this->assertFileExists('./README.md');
+        $this->assertFileExists('./TROUBLESHOOTING.md');
+        $this->assertFileExists('./USAGE.md');
+        $this->assertFileExists('./USE_CASES.md');
+
+        $composeExists = file_exists('./docker-compose.yml') || file_exists('./docker/docker-compose.yml');
+        $this->assertTrue($composeExists);
+
+        $dockerExists = file_exists('./Docker') || file_exists('./docker/Docker')
+        $this->assertTrue($dockerExists);
+    }
+}
+