segmentio · chrisradek · Oct 25, 2022 · Oct 21, 2022 · Oct 21, 2022 · Oct 21, 2022
diff --git a/.changeset/khaki-mayflies-punch.md b/.changeset/khaki-mayflies-punch.md
@@ -0,0 +1,5 @@
+---
+'@segment/analytics-next': minor
+---
+
+Adds a new load option `disableAutoISOConversions` that turns off converting ISO strings in event fields to Dates for integrations.
diff --git a/packages/browser/src/browser/__tests__/integration.test.ts b/packages/browser/src/browser/__tests__/integration.test.ts
@@ -2,7 +2,7 @@
 import { Context } from '@/core/context'
 import { Plugin } from '@/core/plugin'
 import { JSDOM } from 'jsdom'
-import { Analytics } from '../../core/analytics'
+import { Analytics, InitOptions } from '../../core/analytics'
 import { LegacyDestination } from '../../plugins/ajs-destination'
 import { PersistedPriorityQueue } from '../../lib/priority-queue/persisted'
 // @ts-ignore loadLegacySettings mocked dependency is accused as unused
@@ -998,3 +998,137 @@ describe('.Integrations', () => {
     `)
   })
 })
+
+describe('Options', () => {
+  beforeEach(async () => {
+    jest.restoreAllMocks()
+    jest.resetAllMocks()
+
+    const html = `
+    <!DOCTYPE html>
+      <head>
+        <script>'hi'</script>
+      </head>
+      <body>
+      </body>
+    </html>
+    `.trim()
+
+    const jsd = new JSDOM(html, {
+      runScripts: 'dangerously',
+      resources: 'usable',
+      url: 'https://localhost',
+    })
+
+    const windowSpy = jest.spyOn(global, 'window', 'get')
+    windowSpy.mockImplementation(
+      () => jsd.window as unknown as Window & typeof globalThis
+    )
+  })
+
+  describe('disableAutoISOConversion', () => {
+    it('converts iso strings to dates be default', async () => {
+      const [analytics] = await AnalyticsBrowser.load({
+        writeKey,
+      })
+
+      const amplitude = new LegacyDestination(
+        'amplitude',
+        'latest',
+        {
+          apiKey: AMPLITUDE_WRITEKEY,
+        },
+        {}
+      )
+
+      await analytics.register(amplitude)
+      await amplitude.ready()
+
+      const integrationMock = jest.spyOn(amplitude.integration!, 'track')
+      await analytics.track('Hello!', {
+        date: new Date(),
+        iso: '2020-10-10',
+      })
+
+      const [integrationEvent] = integrationMock.mock.lastCall
+
+      expect(integrationEvent.properties()).toEqual({
+        date: expect.any(Date),
+        iso: expect.any(Date),
+      })
+      expect(integrationEvent.timestamp()).toBeInstanceOf(Date)
+    })
+
+    it('converts iso strings to dates be default', async () => {
+      const initOptions: InitOptions = { disableAutoISOConversion: false }
+      const [analytics] = await AnalyticsBrowser.load(
+        {
+          writeKey,
+        },
+        initOptions
+      )
+
+      const amplitude = new LegacyDestination(
+        'amplitude',
+        'latest',
+        {
+          apiKey: AMPLITUDE_WRITEKEY,
+        },
+        initOptions
+      )
+
+      await analytics.register(amplitude)
+      await amplitude.ready()
+
+      const integrationMock = jest.spyOn(amplitude.integration!, 'track')
+      await analytics.track('Hello!', {
+        date: new Date(),
+        iso: '2020-10-10',
+      })
+
+      const [integrationEvent] = integrationMock.mock.lastCall
+
+      expect(integrationEvent.properties()).toEqual({
+        date: expect.any(Date),
+        iso: expect.any(Date),
+      })
+      expect(integrationEvent.timestamp()).toBeInstanceOf(Date)
+    })
+
+    it('does not convert iso strings to dates when `true`', async () => {
+      const initOptions: InitOptions = { disableAutoISOConversion: true }
+      const [analytics] = await AnalyticsBrowser.load(
+        {
+          writeKey,
+        },
+        initOptions
+      )
+
+      const amplitude = new LegacyDestination(
+        'amplitude',
+        'latest',
+        {
+          apiKey: AMPLITUDE_WRITEKEY,
+        },
+        initOptions
+      )
+
+      await analytics.register(amplitude)
+      await amplitude.ready()
+
+      const integrationMock = jest.spyOn(amplitude.integration!, 'track')
+      await analytics.track('Hello!', {
+        date: new Date(),
+        iso: '2020-10-10',
+      })
+
+      const [integrationEvent] = integrationMock.mock.lastCall
+
+      expect(integrationEvent.properties()).toEqual({
+        date: expect.any(Date),
+        iso: '2020-10-10',
+      })
+      expect(integrationEvent.timestamp()).toBeInstanceOf(Date)
+    })
+  })
+})
diff --git a/packages/browser/src/core/analytics/index.ts b/packages/browser/src/core/analytics/index.ts
@@ -67,6 +67,13 @@ export interface InitOptions {
    *
    */
   disableClientPersistence?: boolean
+  /**
+   * Disables automatically converting ISO string event properties into Dates.
+   * ISO string to Date conversions occur right before sending events to a classic device mode integration,
+   * after any destination middleware have been ran.
+   * Defaults to `false`.
+   */
+  disableAutoISOConversion?: boolean
   initialPageview?: boolean
   cookie?: CookieOptions
   user?: UserOptions

diff --git a/packages/browser/src/lib/klona.ts b/packages/browser/src/lib/klona.ts
diff --git a/packages/browser/src/plugins/ajs-destination/index.ts b/packages/browser/src/plugins/ajs-destination/index.ts
@@ -65,6 +65,7 @@ export class LegacyDestination implements Plugin {
   private _initialized = false
   private onReady: Promise<unknown> | undefined
   private onInitialize: Promise<unknown> | undefined
+  private disableAutoISOConversion: boolean
 
   integration: LegacyIntegration | undefined
 
@@ -80,6 +81,7 @@ export class LegacyDestination implements Plugin {
     this.name = name
     this.version = version
     this.settings = { ...settings }
+    this.disableAutoISOConversion = options.disableAutoISOConversion || false
 
     // AJS-Renderer sets an extraneous `type` setting that clobbers
     // existing type defaults. We need to remove it if it's present
@@ -228,7 +230,9 @@ export class LegacyDestination implements Plugin {
       return ctx
     }
 
-    const event = new clz(afterMiddleware, {})
+    const event = new clz(afterMiddleware, {
+      traverse: !this.disableAutoISOConversion,
+    })
 
     ctx.stats.increment('analytics_js.integration.invoke', 1, [
       `method:${eventType}`,

diff --git a/packages/browser/src/plugins/middleware/index.ts b/packages/browser/src/plugins/middleware/index.ts
@@ -3,7 +3,6 @@ import { SegmentEvent } from '../../core/events'
 import { Plugin } from '../../core/plugin'
 import { asPromise } from '../../lib/as-promise'
 import { SegmentFacade, toFacade } from '../../lib/to-facade'
-import { klona } from '../../lib/klona'
 
 export interface MiddlewareParams {
   payload: SegmentFacade
@@ -28,7 +27,11 @@ export async function applyDestinationMiddleware(
   evt: SegmentEvent,
   middleware: DestinationMiddlewareFunction[]
 ): Promise<SegmentEvent | null> {
-  let modifiedEvent = klona(evt)
+  // Clone the event so mutations are localized to a single destination.
+  let modifiedEvent = toFacade(evt, {
+    clone: true,
+    traverse: false,
+  }).rawEvent() as SegmentEvent
   async function applyMiddleware(
     event: SegmentEvent,
     fn: DestinationMiddlewareFunction