feat: add google maps mcp source (#125)

packages/freya-source-google-maps/src/google-maps-source.test.ts

@@ -0,0 +1,135 @@
+import type {
+	McpCallToolParams,
+	McpCallToolResult,
+	McpClient,
+	McpListToolsResult,
+	McpReadResourceParams,
+	McpReadResourceResult,
+} from "@freya/source-mcp"
+
+import { describe, expect, test } from "bun:test"
+
+import { GoogleMapsAction, GoogleMapsSource, GoogleMapsSourceId, GoogleMapsTool } from "./index"
+
+class MockMcpClient implements McpClient {
+	readonly calls: McpCallToolParams[] = []
+
+	async listTools(): Promise<McpListToolsResult> {
+		return {
+			tools: Object.values(GoogleMapsTool).map((name) => ({
+				name,
+				description: `${name} description`,
+			})),
+		}
+	}
+
+	async readResource(_params: McpReadResourceParams): Promise<McpReadResourceResult> {
+		throw new Error("unexpected resource read")
+	}
+
+	async callTool(params: McpCallToolParams): Promise<McpCallToolResult> {
+		this.calls.push(params)
+		return {
+			structuredContent: {
+				tool: params.name,
+				arguments: params.arguments ?? {},
+			},
+		}
+	}
+}
+
+describe("GoogleMapsSource", () => {
+	test("uses the Google Maps source id", () => {
+		const source = new GoogleMapsSource({ client: new MockMcpClient() })
+		expect(source.id).toBe(GoogleMapsSourceId)
+	})
+
+	test("exposes documented Google Maps MCP tools as actions", async () => {
+		const source = new GoogleMapsSource({ client: new MockMcpClient() })
+
+		const actions = await source.listActions()
+
+		expect(Object.keys(actions).sort()).toEqual(Object.values(GoogleMapsAction).sort())
+		expect(actions[GoogleMapsAction.SearchPlaces]!.id).toBe(GoogleMapsAction.SearchPlaces)
+	})
+
+	test("maps action execution to the underlying MCP tool", async () => {
+		const client = new MockMcpClient()
+		const source = new GoogleMapsSource({ client })
+
+		const result = await source.executeAction(GoogleMapsAction.SearchPlaces, {
+			textQuery: "coffee shops near Golden Gate Park",
+			regionCode: "US",
+		})
+
+		expect(client.calls).toEqual([
+			{
+				name: GoogleMapsTool.SearchPlaces,
+				arguments: {
+					textQuery: "coffee shops near Golden Gate Park",
+					regionCode: "US",
+				},
+			},
+		])
+		expect(result).toEqual({
+			tool: GoogleMapsTool.SearchPlaces,
+			arguments: {
+				textQuery: "coffee shops near Golden Gate Park",
+				regionCode: "US",
+			},
+		})
+	})
+
+	test("validates action input before calling the MCP tool", async () => {
+		const client = new MockMcpClient()
+		const source = new GoogleMapsSource({ client })
+
+		await expectRejectsWithMessage(
+			source.executeAction(GoogleMapsAction.SearchPlaces, {}),
+			"textQuery must be a string",
+		)
+		expect(client.calls).toEqual([])
+	})
+
+	test("validates resolve names query objects", async () => {
+		const client = new MockMcpClient()
+		const source = new GoogleMapsSource({ client })
+
+		await expectRejectsWithMessage(
+			source.executeAction(GoogleMapsAction.ResolveNames, { queries: [{}] }),
+			"queries[0].text must be a string",
+		)
+		expect(client.calls).toEqual([])
+	})
+
+	test("does not produce feed items or context by default", async () => {
+		const source = new GoogleMapsSource({ client: new MockMcpClient() })
+
+		const contextEntries = await source.fetchContext(undefined as never)
+		const items = await source.fetchItems(undefined as never)
+
+		expect(contextEntries).toBeNull()
+		expect(items).toEqual([])
+	})
+})
+
+async function expectRejectsWithMessage(
+	promise: Promise<unknown>,
+	expectedMessage: string,
+): Promise<void> {
+	try {
+		await promise
+	} catch (err) {
+		expect(errorMessage(err)).toContain(expectedMessage)
+		return
+	}
+
+	throw new Error(`Expected promise to reject with "${expectedMessage}"`)
+}
+
+function errorMessage(err: unknown): string {
+	if (err instanceof Error) {
+		return err.message
+	}
+	return String(err)
+}