Add tests using PHPUnit

Tests generated by Junie AI. Might not have the best possible quality
but at least we got something, and if it turns out to be complete
rubbish, we can just throw it out again without any issues, as this is
independent of the actual code base.

1 files changed, 16 insertions, 0 deletions

diff --git a/tests/Stubs/TaskmanagerCallback.php b/tests/Stubs/TaskmanagerCallback.php
new file mode 100644
index 00000000..3db06df8
--- /dev/null
+++ b/tests/Stubs/TaskmanagerCallback.php
@@ -0,0 +1,16 @@
+<?php
+
+class TaskmanagerCallback
+{
+	public static array $callbacks = [];
+
+	public static function reset(): void
+	{
+		self::$callbacks = [];
+	}
+
+	public static function addCallback(array $task, string $name, $arg): void
+	{
+		self::$callbacks[] = ['task' => $task['id'] ?? null, 'name' => $name, 'arg' => $arg];
+	}
+}