Fix 12661 (#12744)

* Revert "persist last-intersected status update and restore when ScrollableList is restored"

This reverts commit 07e26142ef6a8e74bd2ac5e9b461a5a1699bd4c8.

accidentally merged spurious code in https://github.com/tootsuite/mastodon/pull/12661.  https://github.com/tootsuite/mastodon/pull/12735 removes the slowdown that this code was trying to solve; and other functionality successfully restores the view state of the list

* Revert "cache currently-viewing status id to avoid calling redux with identical value"

This reverts commit c93df2159fbd3888a5c48d8a8b8ae61dbbc54b89.

accidentally merged spurious code in https://github.com/tootsuite/mastodon/pull/12661.  https://github.com/tootsuite/mastodon/pull/12735 removes the slowdown that this code was trying to solve; and other functionality successfully restores the view state of the list

app/javascript/mastodon/actions/timelines.js

@@ -17,14 +17,6 @@ export const TIMELINE_LOAD_PENDING = 'TIMELINE_LOAD_PENDING';
 export const TIMELINE_DISCONNECT   = 'TIMELINE_DISCONNECT';
 export const TIMELINE_CONNECT      = 'TIMELINE_CONNECT';
 
-export const CURRENTLY_VIEWING = 'CURRENTLY_VIEWING';
-
-export const updateCurrentlyViewing = (timeline, id) => ({
-  type: CURRENTLY_VIEWING,
-  timeline,
-  id,
-});
-
 export const loadPending = timeline => ({
   type: TIMELINE_LOAD_PENDING,
   timeline,

app/javascript/mastodon/components/intersection_observer_article.js

@@ -20,8 +20,6 @@ export default class IntersectionObserverArticle extends React.Component {
     cachedHeight: PropTypes.number,
     onHeightChange: PropTypes.func,
     children: PropTypes.node,
-    currentlyViewing: PropTypes.number,
-    updateCurrentlyViewing: PropTypes.func,
   };
 
   state = {
@@ -50,8 +48,6 @@ export default class IntersectionObserverArticle extends React.Component {
     );
 
     this.componentMounted = true;
-
-    if(id === this.props.currentlyViewing) this.node.scrollIntoView();
   }
 
   componentWillUnmount () {
@@ -64,8 +60,6 @@ export default class IntersectionObserverArticle extends React.Component {
   handleIntersection = (entry) => {
     this.entry = entry;
 
-    if(entry.intersectionRatio > 0.75 && this.props.updateCurrentlyViewing) this.props.updateCurrentlyViewing(this.id);
-
     scheduleIdleTask(this.calculateHeight);
     this.setState(this.updateStateAfterIntersection);
   }

app/javascript/mastodon/components/scrollable_list.js

@@ -36,8 +36,6 @@ export default class ScrollableList extends PureComponent {
     emptyMessage: PropTypes.node,
     children: PropTypes.node,
     bindToDocument: PropTypes.bool,
-    currentlyViewing: PropTypes.number,
-    updateCurrentlyViewing: PropTypes.func,
   };
 
   static defaultProps = {
@@ -314,8 +312,6 @@ export default class ScrollableList extends PureComponent {
                 listLength={childrenCount}
                 intersectionObserverWrapper={this.intersectionObserverWrapper}
                 saveHeightKey={trackScroll ? `${this.context.router.route.location.key}:${scrollKey}` : null}
-                currentlyViewing={this.props.currentlyViewing}
-                updateCurrentlyViewing={this.props.updateCurrentlyViewing}
               >
                 {React.cloneElement(child, {
                   getScrollPosition: this.getScrollPosition,

app/javascript/mastodon/components/status_list.js

@@ -26,8 +26,6 @@ export default class StatusList extends ImmutablePureComponent {
     emptyMessage: PropTypes.node,
     alwaysPrepend: PropTypes.bool,
     timelineId: PropTypes.string,
-    currentlyViewing: PropTypes.number,
-    updateCurrentlyViewing: PropTypes.func,
   };
 
   static defaultProps = {
@@ -60,12 +58,6 @@ export default class StatusList extends ImmutablePureComponent {
     this.props.onLoadMore(this.props.statusIds.size > 0 ? this.props.statusIds.last() : undefined);
   }, 300, { leading: true })
 
-  updateCurrentlyViewingWithCache = (id) => {
-    if(this.cachedCurrentlyViewing === id) return;
-    this.cachedCurrentlyViewing = id;
-    this.props.updateCurrentlyViewing(id);
-  }
-
   _selectChild (index, align_top) {
     const container = this.node.node;
     const element = container.querySelector(`article:nth-of-type(${index + 1}) .focusable`);
@@ -87,7 +79,6 @@ export default class StatusList extends ImmutablePureComponent {
   render () {
     const { statusIds, featuredStatusIds, shouldUpdateScroll, onLoadMore, timelineId, ...other }  = this.props;
     const { isLoading, isPartial } = other;
-    other.updateCurrentlyViewing = this.updateCurrentlyViewingWithCache;
 
     if (isPartial) {
       return <RegenerationIndicator />;

app/javascript/mastodon/features/ui/containers/status_list_container.js

 import { connect } from 'react-redux';
 import StatusList from '../../../components/status_list';
-import { scrollTopTimeline, loadPending, updateCurrentlyViewing } from '../../../actions/timelines';
+import { scrollTopTimeline, loadPending } from '../../../actions/timelines';
 import { Map as ImmutableMap, List as ImmutableList } from 'immutable';
 import { createSelector } from 'reselect';
 import { debounce } from 'lodash';
@@ -39,7 +39,6 @@ const makeMapStateToProps = () => {
     isPartial: state.getIn(['timelines', timelineId, 'isPartial'], false),
     hasMore:   state.getIn(['timelines', timelineId, 'hasMore']),
     numPending: getPendingStatusIds(state, { type: timelineId }).size,
-    currentlyViewing: state.getIn(['timelines', timelineId, 'currentlyViewing'], -1),
   });
 
   return mapStateToProps;
@@ -57,7 +56,6 @@ const mapDispatchToProps = (dispatch, { timelineId }) => ({
 
   onLoadPending: () => dispatch(loadPending(timelineId)),
 
-  updateCurrentlyViewing: id => dispatch(updateCurrentlyViewing(timelineId, id)),
 });
 
 export default connect(makeMapStateToProps, mapDispatchToProps)(StatusList);

app/javascript/mastodon/reducers/timelines.js

@@ -9,7 +9,6 @@ import {
   TIMELINE_CONNECT,
   TIMELINE_DISCONNECT,
   TIMELINE_LOAD_PENDING,
-  CURRENTLY_VIEWING,
 } from '../actions/timelines';
 import {
   ACCOUNT_BLOCK_SUCCESS,
@@ -29,7 +28,6 @@ const initialTimeline = ImmutableMap({
   hasMore: true,
   pendingItems: ImmutableList(),
   items: ImmutableList(),
-  currentlyViewing: -1,
 });
 
 const expandNormalizedTimeline = (state, timeline, statuses, next, isPartial, isLoadingRecent, usePendingItems) => {
@@ -170,8 +168,6 @@ export default function timelines(state = initialState, action) {
       initialTimeline,
       map => map.set('online', false).update(action.usePendingItems ? 'pendingItems' : 'items', items => items.first() ? items.unshift(null) : items)
     );
-  case CURRENTLY_VIEWING:
-    return state.update(action.timeline, initialTimeline, map => map.set('currentlyViewing', action.id));
   default:
     return state;
   }