1 files changed, 48 insertions, 0 deletions
diff --git a/src/features/surface-host/logic/message-queue.test.ts b/src/features/surface-host/logic/message-queue.test.ts
new file mode 100644
index 0000000..ce078d9
--- /dev/null
+++ b/src/features/surface-host/logic/message-queue.test.ts
@@ -0,0 +1,48 @@
+import type { QueuedMessage } from "@dispatch/wire";
+import { describe, expect, it } from "vitest";
+import { parseMessageQueuePayload } from "./message-queue";
+
+const msg = (id: string, text: string, queuedAt = 1_700_000_000_000): QueuedMessage => ({
+	id,
+	text,
+	queuedAt,
+});
+
+describe("parseMessageQueuePayload", () => {
+	it("parses a well-formed payload with messages", () => {
+		const data = parseMessageQueuePayload({
+			messages: [msg("m1", "steer left"), msg("m2", "actually, go right")],
+		});
+		expect(data).toEqual({
+			messages: [msg("m1", "steer left"), msg("m2", "actually, go right")],
+		});
+	});
+
+	it("parses an empty-messages payload (queue is empty)", () => {
+		expect(parseMessageQueuePayload({ messages: [] })).toEqual({ messages: [] });
+	});
+
+	it("preserves message order", () => {
+		const data = parseMessageQueuePayload({
+			messages: [msg("a", "first"), msg("b", "second"), msg("c", "third")],
+		});
+		expect(data?.messages.map((m) => m.id)).toEqual(["a", "b", "c"]);
+	});
+
+	it.each([
+		["null", null],
+		["a number", 7],
+		["a string", "nope"],
+		["missing messages key", { foo: [] }],
+		["messages not an array", { messages: "x" }],
+		["entry not an object", { messages: ["x"] }],
+		["entry missing id", { messages: [{ text: "x", queuedAt: 1 }] }],
+		["entry with non-string id", { messages: [{ id: 1, text: "x", queuedAt: 1 }] }],
+		["entry missing text", { messages: [{ id: "m1", queuedAt: 1 }] }],
+		["entry with non-string text", { messages: [{ id: "m1", text: 1, queuedAt: 1 }] }],
+		["entry missing queuedAt", { messages: [{ id: "m1", text: "x" }] }],
+		["entry with non-finite queuedAt", { messages: [msg("m1", "x", Number.NaN)] }],
+	])("returns null for invalid payload: %s", (_label, payload) => {
+		expect(parseMessageQueuePayload(payload)).toBeNull();
+	});
+});