daily-email: add 2023-08-17

Writing custom assertions in your tests

src/content/daily-email/2023-08-17.md

@@ -0,0 +1,29 @@
+---
+title: >
+  Writing custom assertions in your tests
+pubDate: 2023-08-17
+permalink: >
+  archive/2023/08/17/writing-custom-assertions-in-your-tests
+tags:
+  - automated-testing
+  - test-driven-development
+---
+
+Writing custom assertions is a great way to clean up your test code.
+
+Here's an example from one of my client Drupal projects:
+
+```php
+private static function assertProductVariationHasPrice(ProductVariationInterface $productVariation, string $expectedPrice): void {
+  self::assertSame(
+    actual: $productVariation->getPrice()->getNumber(),
+    expected: $expectedPrice,
+  );
+}
+```
+
+This one wraps a single assertion, but they could also include multiple assertions or additional steps.
+
+## Here's the thing
+
+A custom assertion is a simple function but it makes the test code more readable and less repetitive.