feat: More obvious loading state when submitting a post (#35153)

app/javascript/mastodon/components/button/button.stories.tsx

@@ -11,6 +11,7 @@ const meta = {
     compact: false,
     dangerous: false,
     disabled: false,
+    loading: false,
     onClick: fn(),
   },
   argTypes: {
@@ -41,16 +42,6 @@ const buttonTest: Story['play'] = async ({ args, canvas, userEvent }) => {
   await expect(args.onClick).toHaveBeenCalled();
 };
 
-const disabledButtonTest: Story['play'] = async ({
-  args,
-  canvas,
-  userEvent,
-}) => {
-  const button = await canvas.findByRole('button');
-  await userEvent.click(button);
-  await expect(args.onClick).not.toHaveBeenCalled();
-};
-
 export const Primary: Story = {
   args: {
     children: 'Primary button',
@@ -82,6 +73,18 @@ export const Dangerous: Story = {
   play: buttonTest,
 };
 
+const disabledButtonTest: Story['play'] = async ({
+  args,
+  canvas,
+  userEvent,
+}) => {
+  const button = await canvas.findByRole('button');
+  await userEvent.click(button);
+  // Disabled controls can't be focused
+  await expect(button).not.toHaveFocus();
+  await expect(args.onClick).not.toHaveBeenCalled();
+};
+
 export const PrimaryDisabled: Story = {
   args: {
     ...Primary.args,
@@ -97,3 +100,24 @@ export const SecondaryDisabled: Story = {
   },
   play: disabledButtonTest,
 };
+
+const loadingButtonTest: Story['play'] = async ({
+  args,
+  canvas,
+  userEvent,
+}) => {
+  const button = await canvas.findByRole('button', {
+    name: 'Primary button Loading…',
+  });
+  await userEvent.click(button);
+  await expect(button).toHaveFocus();
+  await expect(args.onClick).not.toHaveBeenCalled();
+};
+
+export const Loading: Story = {
+  args: {
+    ...Primary.args,
+    loading: true,
+  },
+  play: loadingButtonTest,
+};

app/javascript/mastodon/components/button/index.tsx

@@ -3,12 +3,15 @@ import { useCallback } from 'react';
 
 import classNames from 'classnames';
 
+import { LoadingIndicator } from 'mastodon/components/loading_indicator';
+
 interface BaseProps
   extends Omit<React.ButtonHTMLAttributes<HTMLButtonElement>, 'children'> {
   block?: boolean;
   secondary?: boolean;
   compact?: boolean;
   dangerous?: boolean;
+  loading?: boolean;
 }
 
 interface PropsChildren extends PropsWithChildren<BaseProps> {
@@ -34,6 +37,7 @@ export const Button: React.FC<Props> = ({
   secondary,
   compact,
   dangerous,
+  loading,
   className,
   title,
   text,
@@ -42,13 +46,18 @@ export const Button: React.FC<Props> = ({
 }) => {
   const handleClick = useCallback<React.MouseEventHandler<HTMLButtonElement>>(
     (e) => {
-      if (!disabled && onClick) {
+      if (disabled || loading) {
+        e.stopPropagation();
+        e.preventDefault();
+      } else if (onClick) {
         onClick(e);
       }
     },
-    [disabled, onClick],
+    [disabled, loading, onClick],
   );
 
+  const label = text ?? children;
+
   return (
     <button
       className={classNames('button', className, {
@@ -56,14 +65,27 @@ export const Button: React.FC<Props> = ({
         'button--compact': compact,
         'button--block': block,
         'button--dangerous': dangerous,
+        loading,
       })}
-      disabled={disabled}
+      // Disabled buttons can't have focus, so we don't really
+      // disable the button during loading
+      disabled={disabled && !loading}
+      aria-disabled={loading}
+      // If the loading prop is used, announce label changes
+      aria-live={loading !== undefined ? 'polite' : undefined}
       onClick={handleClick}
       title={title}
       type={type}
       {...props}
     >
-      {text ?? children}
+      {loading ? (
+        <>
+          <span className='button__label-wrapper'>{label}</span>
+          <LoadingIndicator role='none' />
+        </>
+      ) : (
+        label
+      )}
     </button>
   );
 };

app/javascript/mastodon/components/loading_indicator.tsx

@@ -6,15 +6,34 @@ const messages = defineMessages({
   loading: { id: 'loading_indicator.label', defaultMessage: 'Loading…' },
 });
 
-export const LoadingIndicator: React.FC = () => {
+interface LoadingIndicatorProps {
+  /**
+   * Use role='none' to opt out of the current default role 'progressbar'
+   * and aria attributes which we should re-visit to check if they're appropriate.
+   * In Firefox the aria-label is not applied, instead an implied value of `50` is
+   * used as the label.
+   */
+  role?: string;
+}
+
+export const LoadingIndicator: React.FC<LoadingIndicatorProps> = ({
+  role = 'progressbar',
+}) => {
   const intl = useIntl();
 
+  const a11yProps =
+    role === 'progressbar'
+      ? ({
+          role,
+          'aria-busy': true,
+          'aria-live': 'polite',
+        } as const)
+      : undefined;
+
   return (
     <div
       className='loading-indicator'
-      role='progressbar'
+      {...a11yProps}
-      aria-busy
-      aria-live='polite'
       aria-label={intl.formatMessage(messages.loading)}
     >
       <CircularProgress size={50} strokeWidth={6} />

app/javascript/mastodon/features/compose/components/compose_form.jsx

@@ -12,9 +12,10 @@ import { length } from 'stringz';
 
 import { missingAltTextModal } from 'mastodon/initial_state';
 
-import AutosuggestInput from '../../../components/autosuggest_input';
+import AutosuggestInput from 'mastodon/components/autosuggest_input';
-import AutosuggestTextarea from '../../../components/autosuggest_textarea';
+import AutosuggestTextarea from 'mastodon/components/autosuggest_textarea';
-import { Button } from '../../../components/button';
+import { Button } from 'mastodon/components/button';
+import { LoadingIndicator } from 'mastodon/components/loading_indicator';
 import EmojiPickerDropdown from '../containers/emoji_picker_dropdown_container';
 import PollButtonContainer from '../containers/poll_button_container';
 import PrivacyDropdownContainer from '../containers/privacy_dropdown_container';
@@ -225,9 +226,8 @@ class ComposeForm extends ImmutablePureComponent {
   };
 
   render () {
-    const { intl, onPaste, autoFocus, withoutNavigation, maxChars } = this.props;
+    const { intl, onPaste, autoFocus, withoutNavigation, maxChars, isSubmitting } = this.props;
     const { highlighted } = this.state;
-    const disabled = this.props.isSubmitting;
 
     return (
       <form className='compose-form' onSubmit={this.handleSubmit}>
@@ -246,7 +246,7 @@ class ComposeForm extends ImmutablePureComponent {
                 <AutosuggestInput
                   placeholder={intl.formatMessage(messages.spoiler_placeholder)}
                   value={this.props.spoilerText}
-                  disabled={disabled}
+                  disabled={isSubmitting}
                   onChange={this.handleChangeSpoilerText}
                   onKeyDown={this.handleKeyDown}
                   ref={this.setSpoilerText}
@@ -268,7 +268,7 @@ class ComposeForm extends ImmutablePureComponent {
             <AutosuggestTextarea
               ref={this.textareaRef}
               placeholder={intl.formatMessage(messages.placeholder)}
-              disabled={disabled}
+              disabled={isSubmitting}
               value={this.props.text}
               onChange={this.handleChange}
               suggestions={this.props.suggestions}
@@ -305,9 +305,15 @@ class ComposeForm extends ImmutablePureComponent {
                 <Button
                   type='submit'
                   compact
-                  text={intl.formatMessage(this.props.isEditing ? messages.saveChanges : (this.props.isInReply ? messages.reply : messages.publish))}
                   disabled={!this.canSubmit()}
-                />
+                  loading={isSubmitting}
+                >
+                  {intl.formatMessage(
+                    this.props.isEditing ?
+                      messages.saveChanges : 
+                      (this.props.isInReply ? messages.reply : messages.publish)
+                  )}
+                </Button>
               </div>
             </div>
           </div>

app/javascript/styles/mastodon/components.scss

@@ -249,6 +249,21 @@
     width: 100%;
   }
 
+  &.loading {
+    cursor: wait;
+
+    .button__label-wrapper {
+      // Hide the label only visually, so that
+      // it keeps its layout and accessibility
+      opacity: 0;
+    }
+
+    .loading-indicator {
+      position: absolute;
+      inset: 0;
+    }
+  }
+
   .icon {
     width: 18px;
     height: 18px;
@@ -4645,14 +4660,20 @@ a.status-card {
 .icon-button .loading-indicator {
   position: static;
   transform: none;
+  color: inherit;
 
   .circular-progress {
-    color: $primary-text-color;
+    color: inherit;
     width: 22px;
     height: 22px;
   }
 }
 
+.button--compact .loading-indicator .circular-progress {
+  width: 17px;
+  height: 17px;
+}
+
 .icon-button .loading-indicator .circular-progress {
   color: lighten($ui-base-color, 26%);
   width: 12px;