Squashed 'third_party/pi/' content from commit d981de122

git-subtree-dir: third_party/pi
git-subtree-split: d981de1229ef899957bbe968bc8dcda02a21f477

packages/coding-agent/test/experimental-slash-commands.test.ts

@@ -0,0 +1,96 @@
+import { createFacetHost, defineFacet } from "@earendil-works/chord";
+import { describe, expect, test, vi } from "vitest";
+import { SlashCommands } from "../src/experimental/services/slash-commands.ts";
+import {
+	createSlashCommandsRuntimeFacet,
+	SlashCommandRegistry,
+} from "../src/experimental/services/slash-commands-provider.ts";
+
+describe("experimental slash command facets", () => {
+	test("registers and removes contributions", () => {
+		const registry = new SlashCommandRegistry();
+		const snapshots: string[][] = [];
+		const unsubscribe = registry.subscribe((commands) => snapshots.push(commands.map(({ name }) => name)));
+		const close = registry.register({ name: "hello", description: "Hello", run: () => undefined });
+		expect(registry.list().map(({ name }) => name)).toEqual(["hello"]);
+		expect(() => registry.register({ name: "hello", run: () => undefined })).toThrow("already registered");
+		close();
+		close();
+		expect(registry.list()).toEqual([]);
+		expect(snapshots).toEqual([[], ["hello"], []]);
+		unsubscribe();
+	});
+
+	test("stages replacements until the previous registration retires", () => {
+		const registry = new SlashCommandRegistry();
+		const first = { name: "hello", description: "First", run: () => undefined };
+		const second = { name: "hello", description: "Second", run: () => undefined };
+		const closeFirst = registry.register(first);
+		const closeSecond = registry.replace(second);
+		expect(registry.list()).toEqual([first]);
+
+		closeSecond();
+		expect(registry.list()).toEqual([first]);
+		const closeReplacement = registry.replace(second);
+		closeFirst();
+		expect(registry.list()).toEqual([second]);
+		closeReplacement();
+		expect(registry.list()).toEqual([]);
+	});
+
+	test("tracks plugin facet reload and unload", async () => {
+		const registry = new SlashCommandRegistry();
+		const originalRun = vi.fn();
+		const host = await createFacetHost({
+			facets: [
+				createSlashCommandsRuntimeFacet(registry),
+				defineFacet({
+					id: "@test/example-hello",
+					setup(env) {
+						const commands = env.use(SlashCommands);
+						env.onActivate(() =>
+							env.own(commands.replace({ name: "hello", description: "Original", run: originalRun })),
+						);
+					},
+				}),
+			],
+		});
+		expect(registry.list().map(({ name }) => name)).toEqual(["hello"]);
+
+		const failure = new Error("replacement failed");
+		await expect(
+			host.reload([
+				defineFacet({
+					id: "@test/example-hello",
+					setup(env) {
+						const commands = env.use(SlashCommands);
+						env.onActivate(() => {
+							env.own(commands.replace({ name: "hello", description: "Failing", run: () => undefined }));
+							throw failure;
+						});
+					},
+				}),
+			]),
+		).rejects.toBe(failure);
+		expect(registry.list()).toEqual([expect.objectContaining({ name: "hello", run: originalRun })]);
+
+		const replacementRun = vi.fn();
+		await host.reload([
+			defineFacet({
+				id: "@test/example-hello",
+				setup(env) {
+					const commands = env.use(SlashCommands);
+					env.onActivate(() =>
+						env.own(commands.replace({ name: "hello", description: "Replacement", run: replacementRun })),
+					);
+				},
+			}),
+		]);
+		expect(registry.list()).toEqual([
+			expect.objectContaining({ name: "hello", description: "Replacement", run: replacementRun }),
+		]);
+
+		await host.dispose();
+		expect(registry.list()).toEqual([]);
+	});
+});