fix: properly cleanup turnstile on unmount

frontend/src/components/Captcha.jsx

@@ -15,6 +15,7 @@ export default function Captcha({ onToken }) {
     }
 
     let cancelled = false
+    let localWidgetId = null
 
     const renderWidget = () => {
       if (
@@ -25,19 +26,21 @@ export default function Captcha({ onToken }) {
         return
       }
 
-      if (widgetIdRef.current !== null) {
+      // Nettoyage d'un éventuel widget précédent.
+      if (localWidgetId !== null) {
         try {
-          window.turnstile.remove(widgetIdRef.current)
+          window.turnstile.remove(localWidgetId)
         } catch {
-          // Widget déjà supprimé
+          // Widget déjà supprimé.
         }
 
+        localWidgetId = null
         widgetIdRef.current = null
       }
 
       containerRef.current.innerHTML = ''
 
-      widgetIdRef.current = window.turnstile.render(
+      localWidgetId = window.turnstile.render(
         containerRef.current,
         {
           sitekey: TURNSTILE_SITE_KEY,
@@ -58,6 +61,8 @@ export default function Captcha({ onToken }) {
           },
         }
       )
+
+      widgetIdRef.current = localWidgetId
     }
 
     const existingScript = document.getElementById(
@@ -66,46 +71,42 @@ export default function Captcha({ onToken }) {
 
     if (window.turnstile) {
       renderWidget()
-      return
+    } else if (existingScript) {
-    }
-
-    if (existingScript) {
       existingScript.addEventListener('load', renderWidget, {
         once: true,
       })
+    } else {
+      const script = document.createElement('script')
 
-      return () => {
+      script.id = TURNSTILE_SCRIPT_ID
-        cancelled = true
+      script.src = TURNSTILE_SCRIPT_URL
-      }
+      script.async = true
+      script.defer = true
+
+      script.addEventListener('load', renderWidget, {
+        once: true,
+      })
+
+      document.head.appendChild(script)
     }
 
-    const script = document.createElement('script')
-
-    script.id = TURNSTILE_SCRIPT_ID
-    script.src = TURNSTILE_SCRIPT_URL
-    script.async = true
-    script.defer = true
-
-    script.addEventListener('load', renderWidget, {
-      once: true,
-    })
-
-    document.head.appendChild(script)
-
     return () => {
       cancelled = true
 
-      if (
+      const widgetId =
-        widgetIdRef.current !== null &&
+        localWidgetId !== null
-        window.turnstile
+          ? localWidgetId
-      ) {
+          : widgetIdRef.current
+
+      if (widgetId !== null && window.turnstile) {
         try {
-          window.turnstile.remove(widgetIdRef.current)
+          window.turnstile.remove(widgetId)
         } catch {
-          // Widget déjà supprimé
+          // Widget déjà supprimé.
         }
       }
 
+      localWidgetId = null
       widgetIdRef.current = null
     }
   }, [onToken])

frontend/src/test/unit/Captcha.test.jsx

@@ -0,0 +1,139 @@
+import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest'
+import { render, cleanup, waitFor } from '@testing-library/react'
+
+vi.mock('../../config/captcha', () => ({
+  CAPTCHA_ENABLED: true,
+  TURNSTILE_SITE_KEY: '0x4AAAAAAE0AF9mR2Y1luOeG',
+}))
+
+import Captcha from '../../components/Captcha'
+
+describe('Captcha', () => {
+  let originalTurnstile
+
+  beforeEach(() => {
+    originalTurnstile = window.turnstile
+
+    document.head
+      .querySelectorAll('#cf-turnstile-script')
+      .forEach((script) => script.remove())
+
+    window.turnstile = undefined
+  })
+
+  afterEach(() => {
+    cleanup()
+    window.turnstile = originalTurnstile
+    vi.restoreAllMocks()
+  })
+
+  it('rend le widget lorsque Turnstile est déjà disponible', async () => {
+    const onToken = vi.fn()
+
+    window.turnstile = {
+      render: vi.fn((container, options) => {
+        options.callback('token-test')
+        return 'widget-1'
+      }),
+      remove: vi.fn(),
+    }
+
+    render(<Captcha onToken={onToken} />)
+
+    await waitFor(() => {
+      expect(window.turnstile.render).toHaveBeenCalled()
+    })
+
+    expect(onToken).toHaveBeenCalledWith('token-test')
+  })
+
+  it('gère expiration et erreur du widget', async () => {
+    const onToken = vi.fn()
+    let options
+
+    window.turnstile = {
+      render: vi.fn((container, opts) => {
+        options = opts
+        return 'widget-2'
+      }),
+      remove: vi.fn(),
+    }
+
+    render(<Captcha onToken={onToken} />)
+
+    await waitFor(() => {
+      expect(options).toBeDefined()
+    })
+
+    options['expired-callback']()
+    options['error-callback']()
+
+    expect(onToken).toHaveBeenNthCalledWith(1, '')
+    expect(onToken).toHaveBeenNthCalledWith(2, '')
+  })
+
+  it('charge Turnstile lorsque le script existe déjà', async () => {
+    const onToken = vi.fn()
+
+    const script = document.createElement('script')
+    script.id = 'cf-turnstile-script'
+    document.head.appendChild(script)
+
+    render(<Captcha onToken={onToken} />)
+
+    window.turnstile = {
+      render: vi.fn(() => 'widget-3'),
+      remove: vi.fn(),
+    }
+
+    script.dispatchEvent(new Event('load'))
+
+    await waitFor(() => {
+      expect(window.turnstile.render).toHaveBeenCalled()
+    })
+  })
+
+  it('supprime le widget au démontage', async () => {
+    const onToken = vi.fn()
+    const remove = vi.fn()
+
+    window.turnstile = {
+      render: vi.fn(() => 'widget-4'),
+      remove,
+    }
+
+    const { unmount } = render(<Captcha onToken={onToken} />)
+
+    await waitFor(() => {
+      expect(window.turnstile.render).toHaveBeenCalledTimes(1)
+    })
+
+    // Le widget est bien créé avant le démontage.
+    unmount()
+
+    expect(remove).toHaveBeenCalledWith('widget-4')
+  })
+
+  it('tolère une erreur lors de la suppression du widget', async () => {
+    const onToken = vi.fn()
+    const remove = vi.fn(() => {
+      throw new Error('widget déjà supprimé')
+    })
+
+    window.turnstile = {
+      render: vi.fn(() => 'widget-5'),
+      remove,
+    }
+
+    const { unmount } = render(<Captcha onToken={onToken} />)
+
+    await waitFor(() => {
+      expect(window.turnstile.render).toHaveBeenCalledTimes(1)
+    })
+
+    expect(() => unmount()).not.toThrow()
+
+    expect(remove).toHaveBeenCalledWith('widget-5')
+  })
+
+})