feat(ai,coding-agent): add faux provider and ModelRegistry factories

packages/coding-agent/test/suite/harness.ts

@@ -0,0 +1,141 @@
+/**
+ * Local test harness for the new coding-agent test suite.
+ */
+
+import { existsSync, mkdirSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import type { AgentTool } from "@mariozechner/pi-agent-core";
+import { Agent } from "@mariozechner/pi-agent-core";
+import type { FauxModelDefinition, FauxProviderRegistration, FauxResponseStep, Model } from "@mariozechner/pi-ai";
+import { registerFauxProvider } from "@mariozechner/pi-ai";
+import { AgentSession, type AgentSessionEvent } from "../../src/core/agent-session.js";
+import { AuthStorage } from "../../src/core/auth-storage.js";
+import { ModelRegistry } from "../../src/core/model-registry.js";
+import { SessionManager } from "../../src/core/session-manager.js";
+import type { Settings } from "../../src/core/settings-manager.js";
+import { SettingsManager } from "../../src/core/settings-manager.js";
+import type { ExtensionFactory, ResourceLoader } from "../../src/index.js";
+import {
+	type CreateTestExtensionsResultInput,
+	createTestExtensionsResult,
+	createTestResourceLoader,
+} from "../utilities.js";
+
+export interface HarnessOptions {
+	models?: FauxModelDefinition[];
+	settings?: Partial<Settings>;
+	systemPrompt?: string;
+	tools?: AgentTool[];
+	resourceLoader?: ResourceLoader;
+	extensionFactories?: Array<ExtensionFactory | CreateTestExtensionsResultInput>;
+}
+
+export interface Harness {
+	session: AgentSession;
+	sessionManager: SessionManager;
+	settingsManager: SettingsManager;
+	faux: FauxProviderRegistration;
+	models: [Model<string>, ...Model<string>[]];
+	getModel(): Model<string>;
+	getModel(modelId: string): Model<string> | undefined;
+	setResponses: (responses: FauxResponseStep[]) => void;
+	appendResponses: (responses: FauxResponseStep[]) => void;
+	getPendingResponseCount: () => number;
+	events: AgentSessionEvent[];
+	eventsOfType<T extends AgentSessionEvent["type"]>(type: T): Extract<AgentSessionEvent, { type: T }>[];
+	tempDir: string;
+	cleanup: () => void;
+}
+
+function createTempDir(): string {
+	const tempDir = join(tmpdir(), `pi-suite-${Date.now()}-${Math.random().toString(36).slice(2)}`);
+	mkdirSync(tempDir, { recursive: true });
+	return tempDir;
+}
+
+export async function createHarness(options: HarnessOptions = {}): Promise<Harness> {
+	const tempDir = createTempDir();
+	const fauxProvider: FauxProviderRegistration = registerFauxProvider({
+		models: options.models,
+	});
+	fauxProvider.setResponses([]);
+	const model = fauxProvider.getModel();
+	const toolMap = options.tools ? Object.fromEntries(options.tools.map((tool) => [tool.name, tool])) : undefined;
+
+	const agent = new Agent({
+		getApiKey: () => "faux-key",
+		initialState: {
+			model,
+			systemPrompt: options.systemPrompt ?? "You are a test assistant.",
+			tools: [],
+		},
+	});
+
+	const sessionManager = SessionManager.inMemory();
+	const settingsManager = SettingsManager.inMemory(options.settings);
+
+	const authStorage = AuthStorage.inMemory();
+	authStorage.setRuntimeApiKey(model.provider, "faux-key");
+	const modelRegistry = ModelRegistry.inMemory(authStorage);
+	modelRegistry.registerProvider(model.provider, {
+		baseUrl: model.baseUrl,
+		apiKey: "faux-key",
+		api: fauxProvider.api,
+		models: fauxProvider.models.map((registeredModel) => ({
+			id: registeredModel.id,
+			name: registeredModel.name,
+			api: registeredModel.api,
+			reasoning: registeredModel.reasoning,
+			input: registeredModel.input,
+			cost: registeredModel.cost,
+			contextWindow: registeredModel.contextWindow,
+			maxTokens: registeredModel.maxTokens,
+			baseUrl: registeredModel.baseUrl,
+		})),
+	});
+	const extensionsResult = options.extensionFactories
+		? await createTestExtensionsResult(options.extensionFactories, tempDir)
+		: undefined;
+	const resourceLoader =
+		options.resourceLoader ?? createTestResourceLoader(extensionsResult ? { extensionsResult } : undefined);
+
+	const session = new AgentSession({
+		agent,
+		sessionManager,
+		settingsManager,
+		cwd: tempDir,
+		modelRegistry,
+		resourceLoader,
+		baseToolsOverride: toolMap,
+	});
+
+	const events: AgentSessionEvent[] = [];
+	session.subscribe((event) => {
+		events.push(event);
+	});
+
+	return {
+		session,
+		sessionManager,
+		settingsManager,
+		faux: fauxProvider,
+		models: fauxProvider.models,
+		getModel: fauxProvider.getModel,
+		setResponses: fauxProvider.setResponses,
+		appendResponses: fauxProvider.appendResponses,
+		getPendingResponseCount: fauxProvider.getPendingResponseCount,
+		events,
+		eventsOfType<T extends AgentSessionEvent["type"]>(type: T) {
+			return events.filter((event): event is Extract<AgentSessionEvent, { type: T }> => event.type === type);
+		},
+		tempDir,
+		cleanup() {
+			session.dispose();
+			fauxProvider.unregister();
+			if (existsSync(tempDir)) {
+				rmSync(tempDir, { recursive: true });
+			}
+		},
+	};
+}