feat: add toBeKebabCase

src/Mixins/Expectation.php

@@ -1021,4 +1021,16 @@ final class Expectation
 
         return $this;
     }
+
+    /**
+     * Asserts that the value is kebab-case.
+     *
+     * @return self<TValue>
+     */
+    public function toBeKebabCase(string $message = ''): self
+    {
+        Assert::assertTrue((bool) preg_match('/^[\p{Ll}-]+$/u', (string) $this->value), $message);
+
+        return $this;
+    }
 }

tests/Features/Expect/toBeKebabCase.php

@@ -0,0 +1,23 @@
+<?php
+
+use PHPUnit\Framework\ExpectationFailedException;
+
+test('pass', function () {
+    expect('abc')->toBeKebabCase();
+    expect('abc-def')->toBeKebabCase();
+    expect('abc_def')->not->toBeKebabCase();
+    expect('abcDef')->not->toBeKebabCase();
+    expect('AbcDef')->not->toBeKebabCase();
+});
+
+test('failures', function () {
+    expect('Abc')->toBeKebabCase();
+})->throws(ExpectationFailedException::class);
+
+test('failures with custom message', function () {
+    expect('Abc')->toBeKebabCase('oh no!');
+})->throws(ExpectationFailedException::class, 'oh no!');
+
+test('not failures', function () {
+    expect('abc-def')->not->toBeKebabCase();
+})->throws(ExpectationFailedException::class);