feat(tests): add tests for Actions

tests/src/flextype/core/ActionsTest.php

@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types = 1);
+
+use Flextype\Actions;
+
+test('test getInstance() method', function() {
+    $this->assertInstanceOf(Actions::class, Actions::getInstance());
+});
+
+test('test registry() helper', function() {
+    $this->assertEquals(Actions::getInstance(), registry());
+    $this->assertInstanceOf(Actions::class, registry());
+});
+
+test('test actions uniqueness', function() {
+    $firstCall = Actions::getInstance();
+    $secondCall = Actions::getInstance();
+
+    $this->assertInstanceOf(Actions::class, $firstCall);
+    $this->assertSame($firstCall, $secondCall);
+});
+
+test('test macro() method', function (): void {
+    Actions::getInstance()->set('foo', 'bar');
+
+    Actions::macro('customMethod', function() {
+        return $this->count();
+    });
+
+    $registry = Actions::getInstance();
+    $this->assertEquals(1, $registry->customMethod());
+});