feat : composable de navigation mois/année du calendrier (#MUI-33)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/components/malio/date/composables/useCalendarView.test.ts

@@ -0,0 +1,68 @@
+import {afterEach, beforeEach, describe, expect, it, vi} from 'vitest'
+import {ref} from 'vue'
+import {useCalendarView} from './useCalendarView'
+
+describe('useCalendarView', () => {
+  beforeEach(() => {
+    vi.useFakeTimers()
+    vi.setSystemTime(new Date(2026, 4, 19)) // 19 mai 2026
+  })
+  afterEach(() => vi.useRealTimers())
+
+  it('initialises to the current month and year', () => {
+    const {currentMonth, currentYear} = useCalendarView(ref('days'))
+    expect(currentMonth.value).toBe(4)
+    expect(currentYear.value).toBe(2026)
+  })
+
+  it('goToNext advances the month in days view', () => {
+    const {currentMonth, goToNext} = useCalendarView(ref('days'))
+    goToNext()
+    expect(currentMonth.value).toBe(5)
+  })
+
+  it('rolls December to January and bumps the year', () => {
+    const {currentMonth, currentYear, goToNext} = useCalendarView(ref('days'))
+    currentMonth.value = 11
+    goToNext()
+    expect(currentMonth.value).toBe(0)
+    expect(currentYear.value).toBe(2027)
+  })
+
+  it('rolls January to December backwards', () => {
+    const {currentMonth, currentYear, goToPrev} = useCalendarView(ref('days'))
+    currentMonth.value = 0
+    goToPrev()
+    expect(currentMonth.value).toBe(11)
+    expect(currentYear.value).toBe(2025)
+  })
+
+  it('navigates the year in months view', () => {
+    const {currentYear, goToNext, goToPrev} = useCalendarView(ref('months'))
+    goToNext()
+    expect(currentYear.value).toBe(2027)
+    goToPrev()
+    expect(currentYear.value).toBe(2026)
+  })
+
+  it('selectMonth sets the current month', () => {
+    const {currentMonth, selectMonth} = useCalendarView(ref('days'))
+    selectMonth(0)
+    expect(currentMonth.value).toBe(0)
+  })
+
+  it('syncToIso sets month/year from a valid ISO', () => {
+    const {currentMonth, currentYear, syncToIso} = useCalendarView(ref('days'))
+    syncToIso('2025-12-25')
+    expect(currentMonth.value).toBe(11)
+    expect(currentYear.value).toBe(2025)
+  })
+
+  it('syncToIso falls back to today for null/invalid', () => {
+    const {currentMonth, currentYear, syncToIso} = useCalendarView(ref('days'))
+    syncToIso('2025-12-25')
+    syncToIso(null)
+    expect(currentMonth.value).toBe(4)
+    expect(currentYear.value).toBe(2026)
+  })
+})