Squashed 'third_party/pi/' content from commit d981de122

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

packages/coding-agent/test/experimental-plugin-reload.test.ts

@@ -0,0 +1,94 @@
+import { defineFacet, type FacetLoader } from "@earendil-works/chord";
+import { type AgentLane, BACKGROUND_CONTEXT, type LaneSnapshot } from "@earendil-works/pi-agent-core";
+import { describe, expect, test, vi } from "vitest";
+import { SessionPlugins } from "../src/experimental/services/plugins.ts";
+import { createSessionWorkerServices } from "../src/experimental/services/worker.ts";
+
+describe("experimental plugin reload", () => {
+	test("loads and cuts over a fresh Session facet generation", async () => {
+		const activations: number[] = [];
+		const disposals: number[] = [];
+		let generation = 0;
+		const facetLoader: FacetLoader = {
+			async load() {
+				const current = ++generation;
+				return {
+					facets: [
+						defineFacet({
+							id: "reloadable-session-plugin",
+							setup(env) {
+								env.onActivate(() => {
+									activations.push(current);
+								});
+							},
+						}),
+					],
+					async dispose() {
+						disposals.push(current);
+					},
+				};
+			},
+		};
+		const snapshot: LaneSnapshot = {
+			lane: "main",
+			transcript: [],
+			tipId: null,
+			configuration: {
+				model: { provider: "test", modelId: "model" },
+				thinkingLevel: "off",
+				activeToolNames: [],
+			},
+			stats: {
+				messageCount: 0,
+				usage: {
+					input: 0,
+					output: 0,
+					cacheRead: 0,
+					cacheWrite: 0,
+					totalTokens: 0,
+					cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
+				},
+			},
+			operation: null,
+			queues: [],
+			faulted: false,
+		};
+		const lane = {
+			async watch() {
+				return {
+					snapshot,
+					start() {},
+					async resnapshot() {
+						return snapshot;
+					},
+					unsubscribe() {},
+				};
+			},
+			async getModel() {
+				return undefined;
+			},
+			async getThinkingLevel() {
+				return "off" as const;
+			},
+		} as unknown as AgentLane;
+		const services = await createSessionWorkerServices({
+			lane,
+			modelRuntime: undefined,
+			facetLoader,
+			publish: vi.fn(async () => {}),
+		});
+		try {
+			expect(activations).toEqual([1]);
+			await services.invoke(
+				{ serviceId: SessionPlugins.id, member: "reload", args: [] },
+				{ serverConnectionId: "server-1", attachmentId: "attachment-1" },
+				BACKGROUND_CONTEXT,
+			);
+			expect(activations).toEqual([1, 2]);
+			expect(disposals).toEqual([1]);
+		} finally {
+			await services.dispose();
+		}
+		expect(disposals).toEqual([1, 2]);
+	});
+});