Extend functionality to work with pure enums (#6)

* Extend functionality to work with pure enums

* Code review changes

Altered `::values()` to act like `::names()` for backed enums, code style fixes, general cleanups

tests/Pest.php

@@ -56,3 +56,11 @@ enum Status: int
     case PENDING = 0;
     case DONE = 1;
 }
+
+enum Role
+{
+    use InvokableCases, Options, Names, Values;
+
+    case ADMIN;
+    case GUEST;
+}

tests/Pest/InvokableCasesTest.php

@@ -2,18 +2,33 @@
 
 use ArchTech\Enums\Exceptions\UndefinedCaseError;
 
-it('can be used as a static method', function () {
+it('can be used as a static method with backed enums', function () {
     expect(Status::PENDING())->toBe(0);
     expect(Status::DONE())->toBe(1);
 });
 
-it('can be invoked as an instance', function () {
+it('can be used as a static method with pure enums', function () {
+    expect(Role::ADMIN())->toBe('ADMIN');
+    expect(Role::GUEST())->toBe('GUEST');
+});
+
+it('can be invoked as an instance as a backed enum', function () {
     $status = Status::PENDING;
 
     expect($status())->toBe(0);
     expect($status())->toBe($status->value);
 });
 
-it('throws an error when a nonexistent case is being used', function () {
+it('can be invoked as an instance as a pure enum', function () {
+    $role = Role::ADMIN;
+
+    expect($role())->toBe('ADMIN');
+});
+
+it('throws an error when a nonexistent case is being used for backed enums', function () {
     Status::INVALID();
 })->expectException(UndefinedCaseError::class);
+
+it('throws an error when a nonexistent case is being used for pure enums', function () {
+    Role::INVALID();
+})->expectException(UndefinedCaseError::class);

tests/Pest/NamesTest.php

@@ -1,5 +1,9 @@
 <?php
 
-it('can return an array of case names')
+it('can return an array of case names from backed enums')
     ->expect(Status::names())
     ->toBe(['PENDING', 'DONE']);
+
+it('can return an array of case names from pure enums')
+    ->expect(Role::names())
+    ->toBe(['ADMIN', 'GUEST']);

tests/Pest/OptionsTest.php

@@ -1,7 +1,13 @@
 <?php
 
-it('can return an associative array of options')
+it('can return an associative array of options from a backed enum')
     ->expect(Status::options())->toBe([
         'PENDING' => 0,
         'DONE' => 1,
     ]);
+
+it('can return an indexed array of options from a pure enum')
+    ->expect(Role::options())->toBe([
+        0 => 'ADMIN',
+        1 => 'GUEST',
+    ]);

tests/Pest/ValuesTest.php

@@ -1,5 +1,9 @@
 <?php
 
-it('can return an array of case values')
+it('can return an array of case values from a backed enum')
     ->expect(Status::values())
     ->toBe([0, 1]);
+
+it('can return an array of case names from a pure enum')
+    ->expect(Role::values())
+    ->toBe(['ADMIN', 'GUEST']);