Stabilize geocode tests

Author: Mahdi451

src/map/geocode.spec.ts

@@ -1,31 +1,139 @@
-import { describe, expect, test } from 'vitest'
+import { afterEach, beforeEach, describe, expect, test, vi } from 'vitest'
+import type { Position } from 'geojson'
 
+import type { ReverseGeocodingFeature, ReverseGeocodingResponse } from './api-types'
 import { getFullAddress, getPlaceName, reverseGeocode } from './geocode'
 
+const fetchMock = vi.fn()
+
+type MockContext = Partial<ReverseGeocodingFeature['properties']['context']>
+
+function createFeature(fullAddress: string, context: MockContext = {}): ReverseGeocodingFeature {
+  return {
+    type: 'Feature',
+    geometry: {
+      type: 'Point',
+      coordinates: [0, 0],
+    },
+    properties: {
+      feature_type: 'address',
+      name: fullAddress,
+      name_preferred: fullAddress,
+      place_formatted: fullAddress,
+      full_address: fullAddress,
+      context,
+    },
+  } as ReverseGeocodingFeature
+}
+
+function createResponse(feature: ReverseGeocodingFeature): ReverseGeocodingResponse {
+  return {
+    type: 'FeatureCollection',
+    attribution: 'test fixture',
+    features: [feature],
+  } as ReverseGeocodingResponse
+}
+
+function coordinateKey(position: Position): string {
+  return `${position[0].toFixed(6)},${position[1].toFixed(6)}`
+}
+
+function mockReverseGeocode(featuresByCoordinate: Map<string, ReverseGeocodingFeature>) {
+  fetchMock.mockImplementation(async (input: string | URL | Request) => {
+    const rawUrl = typeof input === 'string' ? input : input instanceof URL ? input.toString() : input.url
+    const url = new URL(rawUrl)
+    const key = `${url.searchParams.get('longitude')},${url.searchParams.get('latitude')}`
+    const feature = featuresByCoordinate.get(key)
+    if (!feature) throw new Error(`Unexpected reverse geocode lookup for ${key}`)
+
+    return new Response(JSON.stringify(createResponse(feature)), {
+      status: 200,
+      headers: { 'Content-Type': 'application/json' },
+    })
+  })
+}
+
+beforeEach(() => {
+  fetchMock.mockReset()
+  vi.stubGlobal('fetch', fetchMock)
+})
+
+afterEach(() => {
+  vi.restoreAllMocks()
+  vi.unstubAllGlobals()
+})
+
 describe('reverseGeocode', () => {
-  test('return null if coords are [0, 0]', async () => {
+  test('return null if coords are [0, 0] without calling fetch', async () => {
     expect(await reverseGeocode([0, 0])).toBeNull()
+    expect(fetchMock).not.toHaveBeenCalled()
+  })
+
+  test('return first feature from reverse geocode response', async () => {
+    const position: Position = [-0.10664, 51.514209]
+    const feature = createFeature('133 Fleet Street, City of London, London, EC4A 2BB, United Kingdom')
+    mockReverseGeocode(new Map([[coordinateKey(position), feature]]))
+
+    expect(await reverseGeocode(position)).toEqual(feature)
+    expect(fetchMock).toHaveBeenCalledOnce()
+  })
+
+  test('return null when fetch rejects', async () => {
+    vi.spyOn(console, 'error').mockImplementation(() => {})
+    fetchMock.mockRejectedValueOnce(new Error('network down'))
+
+    expect(await reverseGeocode([-0.10664, 51.514209])).toBeNull()
+  })
+
+  test('return null on non-ok response', async () => {
+    fetchMock.mockResolvedValueOnce(new Response('denied', { status: 429, statusText: 'Too Many Requests' }))
+
+    expect(await reverseGeocode([-0.10664, 51.514209])).toBeNull()
+  })
+
+  test('return null when response json cannot be parsed', async () => {
+    fetchMock.mockResolvedValueOnce(new Response('{', { status: 200, headers: { 'Content-Type': 'application/json' } }))
+
+    expect(await reverseGeocode([-0.10664, 51.514209])).toBeNull()
   })
 })
 
 describe('getFullAddress', () => {
-  test('return null if coords are [0, 0]', async () => {
+  test('return null if coords are [0, 0] without calling fetch', async () => {
     expect(await getFullAddress([0, 0])).toBeNull()
+    expect(fetchMock).not.toHaveBeenCalled()
   })
 
   test('normal usage', async () => {
-    // expect(await getFullAddress([-77.036574, 38.8976765])).toBe('1600 Pennsylvania Avenue Northwest, Washington, District of Columbia 20500, United States')
+    mockReverseGeocode(
+      new Map([
+        [coordinateKey([-0.10664, 51.514209]), createFeature('133 Fleet Street, City of London, London, EC4A 2BB, United Kingdom')],
+        [coordinateKey([-2.076843, 51.894799]), createFeature('4 Montpellier Drive, Cheltenham, GL50 1TX, United Kingdom')],
+      ]),
+    )
+
     expect(await getFullAddress([-0.10664, 51.514209])).toBe('133 Fleet Street, City of London, London, EC4A 2BB, United Kingdom')
     expect(await getFullAddress([-2.076843, 51.894799])).toBe('4 Montpellier Drive, Cheltenham, GL50 1TX, United Kingdom')
   })
 })
 
 describe('getPlaceName', () => {
-  test('return null if coords are [0, 0]', async () => {
+  test('return null if coords are [0, 0] without calling fetch', async () => {
     expect(await getPlaceName([0, 0])).toBeNull()
+    expect(fetchMock).not.toHaveBeenCalled()
   })
 
   test('normal usage', async () => {
+    mockReverseGeocode(
+      new Map([
+        [coordinateKey([-117.168638, 32.723695]), createFeature('', { neighborhood: { name: 'Little Italy' } })],
+        [coordinateKey([-118.192757, 33.763015]), createFeature('', { place: { name: 'Downtown Long Beach' } })],
+        [coordinateKey([-0.113643, 51.504546]), createFeature('', { neighborhood: { name: 'Waterloo' } })],
+        [coordinateKey([5.572254, 50.64428]), createFeature('', { locality: { name: 'Liège' } })],
+        [coordinateKey([-2.236802, 53.480931]), createFeature('', { neighborhood: { name: 'Northern Quarter' } })],
+      ]),
+    )
+
     expect(await getPlaceName([-117.168638, 32.723695])).toBe('Little Italy')
     expect(await getPlaceName([-118.192757, 33.763015])).toBe('Downtown Long Beach')
     expect(await getPlaceName([-0.113643, 51.504546])).toBe('Waterloo')