blog/tests/unit/format.utils.test.ts

import { describe, expect, it } from 'vitest'
import { formatDate, formatDateTime, isoDate } from '../../frontend/shared/utils/format'

const SAMPLE = '2025-01-15T10:30:00.000Z'

describe('formatDate', () => {
  it('formats a date in long it-IT style by default', () => {
    expect(formatDate(SAMPLE)).toBe('15 gennaio 2025')
  })

  it('formats a date in long en-GB style when locale is en', () => {
    expect(formatDate(SAMPLE, 'en')).toBe('15 January 2025')
  })

  it('returns an empty string when unset', () => {
    expect(formatDate(null)).toBe('')
    expect(formatDate(undefined)).toBe('')
  })
})

describe('formatDateTime', () => {
  it('includes both date and time', () => {
    const result = formatDateTime(SAMPLE)
    expect(result).toContain('15 gennaio 2025')
  })

  it('includes both date and time in English', () => {
    const result = formatDateTime(SAMPLE, 'en')
    expect(result).toContain('15 January 2025')
  })

  it('returns an empty string when unset', () => {
    expect(formatDateTime(null)).toBe('')
  })
})

describe('isoDate', () => {
  it('returns an ISO 8601 string', () => {
    expect(isoDate(SAMPLE)).toBe(new Date(SAMPLE).toISOString())
  })

  it('returns an empty string when unset', () => {
    expect(isoDate(null)).toBe('')
    expect(isoDate(undefined)).toBe('')
  })
})