diff options
Diffstat (limited to 'app/assets/javascripts/batch_comments/components/review_bar.vue')
-rw-r--r-- | app/assets/javascripts/batch_comments/components/review_bar.vue | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/app/assets/javascripts/batch_comments/components/review_bar.vue b/app/assets/javascripts/batch_comments/components/review_bar.vue index 3cd1a2525e9..111b670596b 100644 --- a/app/assets/javascripts/batch_comments/components/review_bar.vue +++ b/app/assets/javascripts/batch_comments/components/review_bar.vue @@ -2,10 +2,20 @@ import { mapActions, mapGetters } from 'vuex'; import glFeatureFlagMixin from '~/vue_shared/mixins/gl_feature_flags_mixin'; import { REVIEW_BAR_VISIBLE_CLASS_NAME } from '../constants'; +import { PREVENT_LEAVING_PENDING_REVIEW } from '../i18n'; import PreviewDropdown from './preview_dropdown.vue'; import PublishButton from './publish_button.vue'; import SubmitDropdown from './submit_dropdown.vue'; +function closeInterrupt(event) { + event.preventDefault(); + + // This is the correct way to write backwards-compatible beforeunload listeners + // https://developer.chrome.com/blog/page-lifecycle-api/#the-beforeunload-event + /* eslint-disable-next-line no-return-assign, no-param-reassign */ + return (event.returnValue = PREVENT_LEAVING_PENDING_REVIEW); +} + export default { components: { PreviewDropdown, @@ -25,8 +35,26 @@ export default { }, mounted() { document.body.classList.add(REVIEW_BAR_VISIBLE_CLASS_NAME); + /* + * This stuff is a lot trickier than it looks. + * + * Mandatory reading: https://developer.mozilla.org/en-US/docs/Web/API/Window/beforeunload_event + * Some notable sentences: + * - "[...] browsers may not display prompts created in beforeunload event handlers unless the + * page has been interacted with, or may even not display them at all." + * - "Especially on mobile, the beforeunload event is not reliably fired." + * - "The beforeunload event is not compatible with the back/forward cache (bfcache) [...] + * It is recommended that developers listen for beforeunload only in this scenario, and only + * when they actually have unsaved changes, so as to minimize the effect on performance." + * + * Please ensure that this is really not working before you modify it, because there are a LOT + * of scenarios where browser behavior will make it _seem_ like it's not working, but it actually + * is under the right combination of contexts. + */ + window.addEventListener('beforeunload', closeInterrupt, { capture: true }); }, beforeDestroy() { + window.removeEventListener('beforeunload', closeInterrupt, { capture: true }); document.body.classList.remove(REVIEW_BAR_VISIBLE_CLASS_NAME); }, methods: { |