feat(analytics-utilities): Add date formatting support [MA-1969] (#785)

- Refactor tests to allow using `runUtcTest` in more files.
- Add analytics-specific date format to analytics-utilities.

packages/analytics/analytics-utilities/src/format.spec.tz.ts

@@ -0,0 +1,21 @@
+import { it, expect } from 'vitest'
+import { formatISOTimeWithTZ } from './format'
+import { runNonUtcTest, runUtcTest } from './specUtils'
+
+runNonUtcTest('date formatting, non-UTC', () => {
+  it('formatISOTimeWithTZ should work', () => {
+    const pattern = /20\d{2}-\d\d-\d\dT\d\d:\d\d:\d\d\.\d\d\d[+-]\d\d?:\d\d/
+    const date = new Date('2021-01-01T06:02:03.000Z')
+    expect(formatISOTimeWithTZ(date)).toMatch(pattern)
+    expect(formatISOTimeWithTZ(date.getTime())).toMatch(pattern)
+  })
+})
+
+runUtcTest('date formatting in UTC', () => {
+  it('formatISOTimeWithTZ should work', () => {
+    const str = '2020-01-01T01:02:03.000Z'
+    const date = new Date(str)
+    expect(formatISOTimeWithTZ(date)).toBe(str)
+    expect(formatISOTimeWithTZ(date.getTime())).toBe(str)
+  })
+})

packages/analytics/analytics-utilities/src/format.ts

@@ -0,0 +1,5 @@
+import { format } from 'date-fns'
+
+export function formatISOTimeWithTZ(ts: number | Date) {
+  return format(ts, "yyyy-MM-dd'T'HH:mm:ss.SSSXXX")
+}

packages/analytics/analytics-utilities/src/index.ts

@@ -1,4 +1,5 @@
 export * from './types'
+export * from './format'
 export * from './granularity'
 export * from './queryTime'
 export * from './timeframes'

packages/analytics/analytics-utilities/src/queryTime.spec.tz.ts

@@ -6,6 +6,7 @@ import { DeltaQueryTime, TimeseriesQueryTime, UnaryQueryTime } from './queryTime
 import type { Timeframe } from './timeframes'
 import { datePickerSelectionToTimeframe, TimePeriods } from './timeframes'
 import { formatInTimeZone } from 'date-fns-tz'
+import { runUtcTest } from './specUtils'
 
 const standardizeTimezone = (d: Date) => {
   // Adjust according to the test runner's timezone for consistent results.
@@ -497,10 +498,6 @@ runDstTest('daylight savings time: fall', () => {
   })
 })
 
-const supportsUtc = Intl.DateTimeFormat().resolvedOptions().timeZone === 'UTC'
-
-const runUtcTest = supportsUtc ? describe : describe.skip
-
 runUtcTest('UTC: timezone handling', () => {
   beforeEach(() => {
     vi.useFakeTimers()

packages/analytics/analytics-utilities/src/specUtils.ts

@@ -0,0 +1,8 @@
+import { describe } from 'vitest'
+
+const supportsUtc = Intl.DateTimeFormat().resolvedOptions().timeZone === 'UTC'
+
+// Squash type errors; we don't actually export this file from the package, so it's fine that the type depends on Vitest.
+export const runUtcTest: any = supportsUtc ? describe : describe.skip
+
+export const runNonUtcTest: any = supportsUtc ? describe.skip : describe