Add non-broken fallback text when maxlength/maxwords is 0

app/views/examples/translated/index.njk

@@ -136,7 +136,7 @@
     hint: {
       text: "Peidiwch â chynnwys gwybodaeth bersonol neu ariannol fel eich rhif Yswiriant Gwladol neu fanylion eich cerdyn credyd."
     },
-    fallbackHintText: "Gallwch ddefnyddio hyd at %{count} nod",
+    textareaDescriptionText: "Gallwch ddefnyddio hyd at %{count} nod",
     charactersUnderLimitHtml: {
       one: "Mae gennych %{count} nod ar ôl",
       two: "Mae gennych %{count} nod ar ôl",
@@ -163,7 +163,7 @@
       classes: "govuk-label--l",
       isPageHeading: true
     },
-    fallbackHintText: "Gallwch ddefnyddio hyd at %{count} gair",
+    textareaDescriptionText: "Gallwch ddefnyddio hyd at %{count} gair",
     hint: {
       text: "Peidiwch â chynnwys gwybodaeth bersonol neu ariannol fel eich rhif Yswiriant Gwladol neu fanylion eich cerdyn credyd."
     },

src/govuk/components/character-count/_index.scss

@@ -17,6 +17,15 @@
     @include govuk-font($size: false, $tabular: true);
     margin-top: 0;
     margin-bottom: 0;
+
+    &:after {
+      // Zero-width space that will reserve vertical space when no hint is provided
+      // as:
+      // - setting a min-height is not possible without a magic number
+      //   because the line-height is set by the `govuk-font` call above
+      // - using `:empty` is not possible as the hint macro outputs line breaks
+      content: "\200B";
+    }
   }
 
   .govuk-character-count__message--disabled {

src/govuk/components/character-count/character-count.mjs

@@ -28,6 +28,9 @@ var TRANSLATIONS_DEFAULT = {
   wordsOverLimit: {
     one: 'You have %{count} word too many',
     other: 'You have %{count} words too many'
+  },
+  textareaDescription: {
+    other: ''
   }
 }
 
@@ -118,32 +121,39 @@ CharacterCount.prototype.init = function () {
   }
 
   var $textarea = this.$textarea
-  var $fallbackLimitMessage = document.getElementById($textarea.id + '-info')
+  var $textareaDescription = document.getElementById($textarea.id + '-info')
+
+  // Inject a decription for the textarea if none is present already
+  // for when the component was rendered with no maxlength, maxwords
+  // nor custom textareaDescriptionText
+  if ($textareaDescription.textContent.match(/^\s*$/)) {
+    $textareaDescription.textContent = this.i18n.t('textareaDescription', { count: this.maxLength })
+  }
 
-  // Move the fallback count message to be immediately after the textarea
+  // Move the textarea description to be immediately after the textarea
   // Kept for backwards compatibility
-  $textarea.insertAdjacentElement('afterend', $fallbackLimitMessage)
+  $textarea.insertAdjacentElement('afterend', $textareaDescription)
 
   // Create the *screen reader* specific live-updating counter
   // This doesn't need any styling classes, as it is never visible
   var $screenReaderCountMessage = document.createElement('div')
   $screenReaderCountMessage.className = 'govuk-character-count__sr-status govuk-visually-hidden'
   $screenReaderCountMessage.setAttribute('aria-live', 'polite')
   this.$screenReaderCountMessage = $screenReaderCountMessage
-  $fallbackLimitMessage.insertAdjacentElement('afterend', $screenReaderCountMessage)
+  $textareaDescription.insertAdjacentElement('afterend', $screenReaderCountMessage)
 
   // Create our live-updating counter element, copying the classes from the
-  // fallback element for backwards compatibility as these may have been
+  // textarea description for backwards compatibility as these may have been
   // configured
   var $visibleCountMessage = document.createElement('div')
-  $visibleCountMessage.className = $fallbackLimitMessage.className
+  $visibleCountMessage.className = $textareaDescription.className
   $visibleCountMessage.classList.add('govuk-character-count__status')
   $visibleCountMessage.setAttribute('aria-hidden', 'true')
   this.$visibleCountMessage = $visibleCountMessage
-  $fallbackLimitMessage.insertAdjacentElement('afterend', $visibleCountMessage)
+  $textareaDescription.insertAdjacentElement('afterend', $visibleCountMessage)
 
-  // Hide the fallback limit message
-  $fallbackLimitMessage.classList.add('govuk-visually-hidden')
+  // Hide the textarea description
+  $textareaDescription.classList.add('govuk-visually-hidden')
 
   // Remove hard limit if set
   $textarea.removeAttribute('maxlength')
@@ -373,6 +383,7 @@ export default CharacterCount
  * @property {PluralisedTranslation} [wordsUnderLimit] - Words under limit
  * @property {string} [wordsAtLimit] - Words at limit
  * @property {PluralisedTranslation} [wordsOverLimit] - Words over limit
+ * @property {PluralisedTranslation} [textareaDescription] - Fallback hint
  */
 
 /**

src/govuk/components/character-count/character-count.test.js

@@ -31,7 +31,7 @@ describe('Character count', () => {
       await page.setJavaScriptEnabled(true)
     })
 
-    it('shows the fallback message', async () => {
+    it('shows the textarea description', async () => {
       await goToComponent(page, 'character-count')
       const message = await page.$eval('.govuk-character-count__message', el => el.innerHTML.trim())
 
@@ -55,7 +55,7 @@ describe('Character count', () => {
         expect(srMessage).toBeTruthy()
       })
 
-      it('hides the fallback hint', async () => {
+      it('hides the textarea description', async () => {
         const messageClasses = await page.$eval('.govuk-character-count__message', el => el.className)
         expect(messageClasses).toContain('govuk-visually-hidden')
       })
@@ -429,6 +429,32 @@ describe('Character count', () => {
           const visibility = await page.$eval('.govuk-character-count__status', el => window.getComputedStyle(el).visibility)
           expect(visibility).toEqual('visible')
         })
+
+        it('configures the description of the textarea', async () => {
+          // This tests that a description can be provided through JavaScript attributes
+          // and interpolated with the limit provided to the character count in JS.
+
+          await renderAndInitialise(page, 'character-count', {
+            nunjucksParams:
+              examples[
+                'when neither maxlength/maxwords nor textarea description are set'
+              ],
+            javascriptConfig: {
+              maxlength: 10,
+              i18n: {
+                textareaDescription: {
+                  other: 'No more than %{count} characters'
+                }
+              }
+            }
+          })
+
+          const message = await page.$eval(
+            '.govuk-character-count__message',
+            (el) => el.innerHTML.trim()
+          )
+          expect(message).toEqual('No more than 10 characters')
+        })
       })
 
       describe('via `initAll`', () => {
@@ -579,6 +605,28 @@ describe('Character count', () => {
           )
           expect(message).toEqual('You have 1 word too many')
         })
+
+        it('interpolates the textarea description in data attributes with the maximum set in JavaScript', async () => {
+          // This tests that any textarea description provided through data-attributes
+          // (or the Nunjucks macro), waiting for a maximum to be provided in
+          // JavaScript config, will lead to the message being injected in the
+          // element holding the textarea's accessible description
+          // (and interpolated to replace `%{count}` with the maximum)
+
+          await renderAndInitialise(page, 'character-count', {
+            nunjucksParams:
+              examples['when neither maxlength nor maxwords are set'],
+            javascriptConfig: {
+              maxlength: 10
+            }
+          })
+
+          const message = await page.$eval(
+            '.govuk-character-count__message',
+            (el) => el.innerHTML.trim()
+          )
+          expect(message).toEqual('No more than 10 characters')
+        })
       })
     })
 

src/govuk/components/character-count/character-count.yaml

@@ -37,10 +37,10 @@ params:
   required: false
   description: Options for the hint component.
   isComponent: true
-- name: fallbackHintText
+- name: textareaDescriptionText
   type: string
   required: false
-  description: Text describing the maximum number of characters you can enter, which is announced to screen readers. The text is displayed as a fallback if the character count JavaScript does not run. Depending on how you configure this component and what parameters you add, instances of `%{count}` are replaced by the value of `maxwords`. If not configured, it uses `maxlength`. By default, fallback text is provided in English.
+  description: Text describing the maximum number of characters you can enter, which is announced to screen readers. The text is displayed as a fallback if the character count JavaScript does not run. Depending on how you configure this component and what parameters you add, instances of `%{count}` are replaced by the value of `maxwords`. If not configured, it uses `maxlength`. By default, textarea description is provided in English.
 - name: errorMessage
   type: object
   required: false
@@ -86,13 +86,13 @@ examples:
       label:
         text: Can you provide more detail?
 
-  - name: with custom fallback text
-    description: with no-js fallback text translated into Welsh
+  - name: with custom textarea description
+    description: with textarea description translated into Welsh
     data:
-      name: custom-fallback
-      id: custom-fallback
+      name: custom-textarea-description
+      id: custom-textarea-description
       maxlength: 10
-      fallbackHintText: Gallwch ddefnyddio hyd at %{count} nod
+      textareaDescriptionText: Gallwch ddefnyddio hyd at %{count} nod
 
   - name: with hint
     data:
@@ -187,7 +187,6 @@ examples:
         other: '%{count} words too many'
         one: 'One word too many'
 
-
 # Hidden examples are not shown in the review app, but are used for tests and HTML fixtures
   - name: classes
     hidden: true
@@ -290,3 +289,18 @@ examples:
       name: address
       label:
         text: Full address
+  - name: when neither maxlength nor maxwords are set
+    hidden: true
+    data:
+      id: no-maximum
+      name: no-maximum
+      label:
+        text: Full address
+      textareaDescriptionText: 'No more than %{count} characters'
+  - name: when neither maxlength/maxwords nor textarea description are set
+    hidden: true
+    data:
+      id: no-maximum
+      name: no-maximum
+      label:
+        text: Full address

src/govuk/components/character-count/template.njk

@@ -3,10 +3,19 @@
 {% from "../textarea/macro.njk" import govukTextarea %}
 {% from "../hint/macro.njk" import govukHint %}
 
+{%- set hasNoLimit = (not params.maxwords and not params.maxlength) %}
+
 <div class="govuk-character-count" data-module="govuk-character-count"
 {%- if params.maxlength %} data-maxlength="{{ params.maxlength }}"{% endif %}
 {%- if params.threshold %} data-threshold="{{ params.threshold }}"{% endif %}
 {%- if params.maxwords %} data-maxwords="{{ params.maxwords }}"{% endif %}
+{#
+  Without maxlength or maxwords, we can't guess if the component will count words or characters.
+  We can't guess a default textarea description to be interpolated in JavaScript
+  once the maximum gets configured there.
+  So we only add the attribute if a textarea description was explicitely provided.
+#}
+{%- if hasNoLimit and params.textareaDescriptionText %}{{govukPluralisedI18nAttributes('textarea-description', {other: params.textareaDescriptionText})}}{% endif %}
 {%- if params.charactersUnderLimitText %}{{govukPluralisedI18nAttributes('characters-under-limit', params.charactersUnderLimitText)}}{% endif %}
 {%- if params.charactersAtLimitText %} data-i18n.characters-at-limit="{{ params.charactersAtLimitText | escape}}"{% endif %}
 {%- if params.charactersOverLimitText %}{{govukPluralisedI18nAttributes('characters-over-limit', params.charactersOverLimitText)}}{% endif %}
@@ -34,10 +43,15 @@
     errorMessage: params.errorMessage,
     attributes: params.attributes
   }) }}
-  {%- set fallbackHintLength = params.maxwords or params.maxlength %}
-  {%- set fallbackHintDefault = 'You can enter up to %{count} ' + ('words' if params.maxwords else 'characters') %}
+  {%- set textareaDescriptionLength = params.maxwords or params.maxlength %}
+  {%- set textareaDescriptionText = params.textareaDescriptionText or 'You can enter up to %{count} ' + ('words' if params.maxwords else 'characters') %}
+  {#
+    If the limit is set in JavaScript, we won't be able to interpolate the message
+    until JavaScript, so we only set a text if the `maxlength` or `maxwords` options
+    were provided to the macro.
+  #}
   {{ govukHint({
-    text: (params.fallbackHintText or fallbackHintDefault) | replace('%{count}', fallbackHintLength),
+    text: ((textareaDescriptionText) | replace('%{count}', textareaDescriptionLength) if not hasNoLimit),
     id: params.id + '-info',
     classes: 'govuk-character-count__message' + (' ' + params.countMessage.classes if params.countMessage.classes)
   }) }}

src/govuk/components/character-count/template.test.js

@@ -225,9 +225,9 @@ describe('Character count', () => {
     })
   })
 
-  describe('with custom fallback text', () => {
-    it('allows customisation of the fallback message', () => {
-      const $ = render('character-count', examples['with custom fallback text'])
+  describe('with custom textarea description', () => {
+    it('allows customisation of the textarea description', () => {
+      const $ = render('character-count', examples['with custom textarea description'])
 
       const message = $('.govuk-character-count__message').text().trim()
       expect(message).toEqual('Gallwch ddefnyddio hyd at 10 nod')
@@ -256,4 +256,36 @@ describe('Character count', () => {
       })
     })
   })
+
+  describe('when neither maxlength nor maxwords are set', () => {
+    describe('with textarea description set', () => {
+      // If the template has no maxwords or maxlength to go for
+      // it needs to pass down any textarea description to the JavaScript
+      // so it can inject the limit it may have received at instantiation
+      it('renders the textarea description as a data attribute', () => {
+        const $ = render('character-count', examples['when neither maxlength nor maxwords are set'])
+
+        // Fallback hint is passed as data attribute
+        const $component = $('[data-module]')
+        expect($component.attr('data-i18n.textarea-description.other')).toEqual('No more than %{count} characters')
+
+        // No content is set as the accessible description cannot be interpolated on the backend
+        // It'll be up to the JavaScript to fill it in
+        const $countMessage = $('.govuk-character-count__message')
+        expect($countMessage.html()).toMatch(/^\s*$/) // The macro outputs linebreaks around the hint itself
+      })
+    })
+
+    describe('without textarea description', () => {
+      it('does not render a textarea description data attribute', () => {
+        const $ = render(
+          'character-count',
+          examples['when neither maxlength/maxwords nor textarea description are set']
+        )
+
+        const $component = $('[data-module]')
+        expect($component.attr('data-i18n.textarea-description.other')).toBeFalsy()
+      })
+    })
+  })
 })