test(coding-agent): add session lifecycle characterization suite

packages/coding-agent/test/suite/regressions/2023-queued-slash-command-followup.test.ts

@@ -0,0 +1,80 @@
+import type { AgentTool } from "@mariozechner/pi-agent-core";
+import { fauxAssistantMessage, fauxToolCall } from "@mariozechner/pi-ai";
+import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
+import { Type } from "@sinclair/typebox";
+import { afterEach, describe, expect, it } from "vitest";
+import { createHarness, getAssistantTexts, getUserTexts, type Harness } from "../harness.js";
+
+describe("issue #2023 queued slash-command follow-up", () => {
+	const harnesses: Harness[] = [];
+
+	afterEach(() => {
+		while (harnesses.length > 0) {
+			harnesses.pop()?.cleanup();
+		}
+	});
+
+	it("treats extension-origin queued slash-command follow-ups as raw user text instead of dispatching the command", async () => {
+		let extensionApi: ExtensionAPI | undefined;
+		const commandRuns: string[] = [];
+		let releaseToolExecution: (() => void) | undefined;
+		const toolRelease = new Promise<void>((resolve) => {
+			releaseToolExecution = resolve;
+		});
+		const waitTool: AgentTool = {
+			name: "wait",
+			label: "Wait",
+			description: "Wait for the test to release execution",
+			parameters: Type.Object({}),
+			execute: async () => {
+				await toolRelease;
+				return {
+					content: [{ type: "text", text: "released" }],
+					details: {},
+				};
+			},
+		};
+		const harness = await createHarness({
+			tools: [waitTool],
+			extensionFactories: [
+				(pi) => {
+					extensionApi = pi;
+					pi.registerCommand("testcmd", {
+						description: "Test command",
+						handler: async (args) => {
+							commandRuns.push(args);
+						},
+					});
+				},
+			],
+		});
+		harnesses.push(harness);
+
+		harness.setResponses([
+			fauxAssistantMessage(fauxToolCall("wait", {}), { stopReason: "toolUse" }),
+			fauxAssistantMessage("first turn complete"),
+			fauxAssistantMessage("queued follow-up handled by model"),
+		]);
+
+		const sawToolStart = new Promise<void>((resolve) => {
+			const unsubscribe = harness.session.subscribe((event) => {
+				if (event.type === "tool_execution_start" && event.toolName === "wait") {
+					unsubscribe();
+					resolve();
+				}
+			});
+		});
+
+		const promptPromise = harness.session.prompt("start");
+		await sawToolStart;
+		await new Promise((resolve) => setTimeout(resolve, 0));
+
+		extensionApi?.sendUserMessage("/testcmd queued", { deliverAs: "followUp" });
+		releaseToolExecution?.();
+		await promptPromise;
+
+		expect(commandRuns).toEqual([]);
+		expect(getUserTexts(harness)).toEqual(["start", "/testcmd queued"]);
+		expect(getAssistantTexts(harness)).toContain("queued follow-up handled by model");
+	});
+});