daily-email: add 2023-09-07

What's the simplest test to begin with?

src/content/daily-email/2023-09-07.md

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+---
+title: >
+  What's the simplest test to begin with?
+pubDate: 2023-09-07
+permalink: >
+  archive/2023/09/07/what-s-the-simplest-test-to-begin-with
+tags:
+  - software-development
+  - automated-testing
+  - test-driven-development
+  - php
+  - drupal
+---
+
+When giving talks and workshops or coaching on automated testing and test-driven development, some people may not have written tests before and aren't familiar with the structure or know where to begin.
+
+In the workshops I ran for DrupalCamp London and DrupalCamp NYC, I wanted to cover this first before writing any implementation code.
+
+Where do you put a test class, and what does it contain?
+
+How do you run the tests, and how can you make it pass or fail?
+
+## What we did
+
+To start, we wrote a test for existing functionality within Drupal core - anonymous users can visit the front page.
+
+This is the whole test:
+
+```php
+<?php
+
+namespace Drupal\Tests\my_module\Functional;
+
+use Drupal\Tests\BrowserTestBase;
+use Symfony\Component\HttpFoundation\Response;
+
+class MyModuleTest extends BrowserTestBase {
+
+  protected $defaultTheme = 'stark';
+
+  /** @test */
+  public function the_front_page_loads_for_anonymous_users() {
+    $this->drupalGet('<front>');
+
+    $this->assertResponse(Response::HTTP_OK);
+  }
+
+}
+```
+
+This is a test someone can write, run and see the test pass.
+
+They can then experiment by changing the values to make the test fail in different ways.
+
+## What next?
+
+Then, we tested anonymous users cannot access the administration pages, which is also already the case in Drupal core, and then authenticated users with the correct permissions could access them.
+
+People were getting the idea by now, and we moved on to writing and testing some of our own code.