feat(ui) : TabList — fenêtrage maxVisibleTabs + flèches navigation

Ajout d'une prop maxVisibleTabs activant un fenêtrage carousel (sans
animation) avec flèches gauche/droite. Les flèches sont désactivées aux
bornes, les panneaux hors fenêtre restent montés, et startIndex est
clampé si tabs/maxVisibleTabs changent.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/components/malio/tab/TabList.test.ts

@@ -15,6 +15,7 @@ type TabListProps = {
   tabs: Tab[]
   modelValue?: string
   id?: string
+  maxVisibleTabs?: number
 }
 
 const TabListForTest = TabList as DefineComponent<TabListProps>
@@ -185,3 +186,127 @@ describe('MalioTabList', () => {
     expect(buttons[1].attributes('aria-selected')).toBe('false')
   })
 })
+
+describe('MalioTabList — fenêtrage maxVisibleTabs', () => {
+  const sevenTabs: Tab[] = [
+    {key: 't1', label: 'Tab 1'},
+    {key: 't2', label: 'Tab 2'},
+    {key: 't3', label: 'Tab 3'},
+    {key: 't4', label: 'Tab 4'},
+    {key: 't5', label: 'Tab 5'},
+    {key: 't6', label: 'Tab 6'},
+    {key: 't7', label: 'Tab 7'},
+  ]
+
+  it('renders only maxVisibleTabs buttons and disables prev at start', () => {
+    const wrapper = mountComponent({tabs: sevenTabs, maxVisibleTabs: 5})
+    const buttons = wrapper.findAll('[role="tab"]')
+    expect(buttons).toHaveLength(5)
+    expect(buttons[0].text()).toContain('Tab 1')
+    expect(buttons[4].text()).toContain('Tab 5')
+
+    const prev = wrapper.find('[data-test="tab-prev"]')
+    const next = wrapper.find('[data-test="tab-next"]')
+    expect(prev.exists()).toBe(true)
+    expect(next.exists()).toBe(true)
+    expect(prev.attributes('disabled')).toBeDefined()
+    expect(next.attributes('disabled')).toBeUndefined()
+  })
+
+  it('shifts the window by 1 on next click', async () => {
+    const wrapper = mountComponent({tabs: sevenTabs, maxVisibleTabs: 5})
+
+    await wrapper.find('[data-test="tab-next"]').trigger('click')
+
+    const labels = wrapper.findAll('[role="tab"]').map(b => b.text())
+    expect(labels.some(l => l.includes('Tab 1'))).toBe(false)
+    expect(labels.some(l => l.includes('Tab 6'))).toBe(true)
+    expect(labels).toHaveLength(5)
+
+    expect(wrapper.find('[data-test="tab-prev"]').attributes('disabled')).toBeUndefined()
+  })
+
+  it('disables next at the end and shows the last window', async () => {
+    const wrapper = mountComponent({tabs: sevenTabs, maxVisibleTabs: 5})
+
+    // 7 - 5 = 2 clicks to reach the end
+    await wrapper.find('[data-test="tab-next"]').trigger('click')
+    await wrapper.find('[data-test="tab-next"]').trigger('click')
+
+    const next = wrapper.find('[data-test="tab-next"]')
+    expect(next.attributes('disabled')).toBeDefined()
+
+    const buttons = wrapper.findAll('[role="tab"]')
+    expect(buttons).toHaveLength(5)
+    // last window starts at tabs[length-5] = tabs[2] = Tab 3
+    expect(buttons[0].text()).toContain('Tab 3')
+    expect(buttons[4].text()).toContain('Tab 7')
+  })
+
+  it('clicking next past the end does not overshoot', async () => {
+    const wrapper = mountComponent({tabs: sevenTabs, maxVisibleTabs: 5})
+    const next = wrapper.find('[data-test="tab-next"]')
+
+    await next.trigger('click')
+    await next.trigger('click')
+    await next.trigger('click') // guarded, no-op
+    await next.trigger('click') // guarded, no-op
+
+    const buttons = wrapper.findAll('[role="tab"]')
+    expect(buttons).toHaveLength(5)
+    expect(buttons[0].text()).toContain('Tab 3')
+    expect(buttons[4].text()).toContain('Tab 7')
+  })
+
+  it('renders no arrows and all tabs when maxVisibleTabs is undefined', () => {
+    const wrapper = mountComponent({tabs: sevenTabs})
+    expect(wrapper.findAll('[role="tab"]')).toHaveLength(7)
+    expect(wrapper.find('[data-test="tab-prev"]').exists()).toBe(false)
+    expect(wrapper.find('[data-test="tab-next"]').exists()).toBe(false)
+  })
+
+  it('renders no arrows when maxVisibleTabs >= tabs.length', () => {
+    const wrapper = mountComponent({tabs: sevenTabs, maxVisibleTabs: 7})
+    expect(wrapper.findAll('[role="tab"]')).toHaveLength(7)
+    expect(wrapper.find('[data-test="tab-prev"]').exists()).toBe(false)
+    expect(wrapper.find('[data-test="tab-next"]').exists()).toBe(false)
+  })
+
+  it('selecting a visible tab activates it without moving the window', async () => {
+    const wrapper = mountComponent({tabs: sevenTabs, maxVisibleTabs: 5})
+    const buttons = wrapper.findAll('[role="tab"]')
+
+    await buttons[2].trigger('click')
+
+    const after = wrapper.findAll('[role="tab"]')
+    expect(after[2].attributes('aria-selected')).toBe('true')
+    // window unchanged
+    expect(after[0].text()).toContain('Tab 1')
+    expect(after).toHaveLength(5)
+  })
+
+  it('keeps the active panel rendered even when its tab is outside the window', async () => {
+    const wrapper = mountComponent(
+      {tabs: sevenTabs, maxVisibleTabs: 5, modelValue: 't1'},
+      {t1: '<p>Panel 1</p>'},
+    )
+
+    await wrapper.find('[data-test="tab-next"]').trigger('click')
+    await wrapper.find('[data-test="tab-next"]').trigger('click')
+
+    // Tab 1 is no longer in the window
+    const labels = wrapper.findAll('[role="tab"]').map(b => b.text())
+    expect(labels.some(l => l.includes('Tab 1'))).toBe(false)
+
+    // but its panel is still rendered and visible
+    const panels = wrapper.findAll('[role="tabpanel"]')
+    expect(panels).toHaveLength(7)
+    expect(wrapper.text()).toContain('Panel 1')
+  })
+
+  it('arrows expose aria-labels', () => {
+    const wrapper = mountComponent({tabs: sevenTabs, maxVisibleTabs: 5})
+    expect(wrapper.find('[data-test="tab-prev"]').attributes('aria-label')).toBe('Onglets précédents')
+    expect(wrapper.find('[data-test="tab-next"]').attributes('aria-label')).toBe('Onglets suivants')
+  })
+})