test: add test for changing string case

tests/Unit/Base/Support/StrTest.php

@@ -17,3 +17,32 @@
     ['short enough', 40, '_-.', 'short enough'],
     ['broccoli', 5, '~', 'broc~'],
 ]);
+
+it('changes string case', function (string $string, ?int $flags, string $result) {
+    expect(Str::changeCase($string, $flags))->toBe($result);
+})->with([
+    ['my string', null, 'myString'],
+    ['my string', Str::CASE_KEBAB, 'my-string'],
+    ['my string', Str::CASE_SNAKE, 'my_string'],
+    ['my string', Str::CASE_STUDLY, 'MyString'],
+
+    ['myString', null, 'myString'],
+    ['myString', Str::CASE_SNAKE, 'my_string'],
+    ['myString', Str::CASE_KEBAB, 'my-string'],
+    ['myString', Str::CASE_STUDLY, 'MyString'],
+
+    ['my-string', null, 'myString'],
+    // Kebab can't be converted to snake
+    ['my-string', Str::CASE_KEBAB, 'my-string'],
+    ['my-string', Str::CASE_STUDLY, 'MyString'],
+
+    ['my_string', null, 'myString'],
+    ['my_string', Str::CASE_SNAKE, 'my_string'],
+    // Snake can't be converted to kebab
+    ['my_string', Str::CASE_STUDLY, 'MyString'],
+
+    ['MyString', null, 'myString'],
+    ['MyString', Str::CASE_SNAKE, 'my_string'],
+    ['MyString', Str::CASE_KEBAB, 'my-string'],
+    ['MyString', Str::CASE_STUDLY, 'MyString'],
+]);