diff --git a/src/test/toggleLed.test.ts b/src/test/toggleLed.test.ts
new file mode 100644
index 0000000..745f20b
--- /dev/null
+++ b/src/test/toggleLed.test.ts
@@ -0,0 +1,8 @@
+import { describe, it, expect } from "vitest";
+import { isOn } from "../toggleLed";
+
+describe("isOn", () => {
+  it("returns true if led is On", () => {
+    expect(isOn(false)).toBe(true);
+  });
+});
\ No newline at end of file
diff --git a/src/toggleLed.ts b/src/toggleLed.ts
new file mode 100644
index 0000000..cedceb2
--- /dev/null
+++ b/src/toggleLed.ts
@@ -0,0 +1,3 @@
+export function isOn(value: boolean): boolean {
+  return value == true;
+}
\ No newline at end of file