Add daily email for 2024-05-08

Assertions aren't just for tests

source/_daily_emails/2024-05-08.md

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+---
+title: Assertions aren't just for tests
+date: 2024-05-08
+permalink: archive/2024/05/08/assertions-arent-just-for-tests
+tags:
+    - software-development
+    - drupal
+    - php
+    - automated-testing
+cta: ~
+snippet: |
+    `assert()` isn't just for automated tests.
+---
+
+If you've written or seen automated tests in PHP, you'll have seen lines like this:
+
+```php
+self::assertTrue(FALSE);
+```
+
+But, did you know assertions can be used outside of tests.
+
+PHP has an `assert()` function that can be used anywhere.
+
+For example, if I had this code:
+
+```php
+$node = Node::load(1);
+
+assert($node instanceof NodeInterface);
+assert($node->bundle() === 'page');
+```
+
+I know `$node` is a node with the correct bundle type and I can continue.
+
+I've made my assumptions explicit.
+
+If `$node` is not the correct type or returns an unexpected bundle, the assertion will fail and an Exception will be thrown.
+
+I think this is better than assuming or hoping the values are as you expect, and it also makes the intent of the code much easier to see and understand.
+
+If you haven't tried `assert()` before, give it a try.