Fix reaction-selector reference invalidation

## Issue
When comments are refreshed, each `Comment` gets rendered 4-5 times due to reference invalidation for `othersReacts` (the data didn't actually change).

## Change
For selectors without transformation, there is no need to memoize using `createSelector` -- just access it directly. Also, don't do things like `return a[id] || {}` in a reducer, because the reference to the empty object will be different on each call.

Always return directly from the state so that the same reference is returned.

This simple change avoided the wasted resources needed for `createSelector`, and reduced to render to just 2 (initial render, and when reactions are fetched).

ui/component/comment/index.js

@@ -12,7 +12,7 @@ import { doSetPlayingUri } from 'redux/actions/content';
 import { selectUserVerifiedEmail } from 'redux/selectors/user';
 import {
   selectLinkedCommentAncestors,
-  makeSelectOthersReactionsForComment,
+  selectOthersReactsForComment,
   makeSelectTotalReplyPagesForParentId,
 } from 'redux/selectors/comments';
 import { selectActiveChannelClaim } from 'redux/selectors/app';
@@ -29,7 +29,7 @@ const select = (state, props) => {
     thumbnail: props.authorUri && makeSelectThumbnailForUri(props.authorUri)(state),
     channelIsBlocked: props.authorUri && makeSelectChannelIsMuted(props.authorUri)(state),
     commentingEnabled: IS_WEB ? Boolean(selectUserVerifiedEmail(state)) : true,
-    othersReacts: makeSelectOthersReactionsForComment(reactionKey)(state),
+    othersReacts: selectOthersReactsForComment(state, reactionKey),
     activeChannelClaim,
     myChannels: selectMyChannelClaims(state),
     playingUri: selectPlayingUri(state),

ui/component/commentReactions/index.js

@@ -3,7 +3,7 @@ import Comment from './view';
 import { makeSelectClaimIsMine, makeSelectClaimForUri } from 'redux/selectors/claims';
 import { doResolveUri } from 'redux/actions/claims';
 import { doToast } from 'redux/actions/notifications';
-import { makeSelectMyReactionsForComment, makeSelectOthersReactionsForComment } from 'redux/selectors/comments';
+import { selectMyReactsForComment, selectOthersReactsForComment } from 'redux/selectors/comments';
 import { doCommentReact } from 'redux/actions/comments';
 import { selectActiveChannelClaim } from 'redux/selectors/app';
 
@@ -15,8 +15,8 @@ const select = (state, props) => {
   return {
     claim: makeSelectClaimForUri(props.uri)(state),
     claimIsMine: makeSelectClaimIsMine(props.uri)(state),
-    myReacts: makeSelectMyReactionsForComment(reactionKey)(state),
-    othersReacts: makeSelectOthersReactionsForComment(reactionKey)(state),
+    myReacts: selectMyReactsForComment(state, reactionKey),
+    othersReacts: selectOthersReactsForComment(state, reactionKey),
     activeChannelId,
   };
 };

ui/component/commentReactions/view.jsx

@@ -73,12 +73,12 @@ export default function CommentReactions(props: Props) {
   const shouldHide = !canCreatorReact && hideCreatorLike;
   const creatorLiked = getCountForReact(REACTION_TYPES.CREATOR_LIKE) > 0;
   const likeIcon = SIMPLE_SITE
-    ? myReacts.includes(REACTION_TYPES.LIKE)
+    ? myReacts && myReacts.includes(REACTION_TYPES.LIKE)
       ? ICONS.FIRE_ACTIVE
       : ICONS.FIRE
     : ICONS.UPVOTE;
   const dislikeIcon = SIMPLE_SITE
-    ? myReacts.includes(REACTION_TYPES.DISLIKE)
+    ? myReacts && myReacts.includes(REACTION_TYPES.DISLIKE)
       ? ICONS.SLIME_ACTIVE
       : ICONS.SLIME
     : ICONS.DOWNVOTE;

ui/component/commentsList/index.js

@@ -13,8 +13,8 @@ import {
   selectIsFetchingCommentsById,
   selectIsFetchingReacts,
   makeSelectTotalCommentsCountForUri,
-  selectOthersReactsById,
-  selectMyReactionsByCommentId,
+  selectOthersReacts,
+  selectMyReacts,
   makeSelectCommentIdsForUri,
   selectSettingsByChannelId,
   makeSelectPinnedCommentsForUri,
@@ -47,8 +47,8 @@ const select = (state, props) => {
     isFetchingReacts: selectIsFetchingReacts(state),
     fetchingChannels: selectFetchingMyChannels(state),
     settingsByChannelId: selectSettingsByChannelId(state),
-    myReactsByCommentId: selectMyReactionsByCommentId(state),
-    othersReactsById: selectOthersReactsById(state),
+    myReactsByCommentId: selectMyReacts(state),
+    othersReactsById: selectOthersReacts(state),
     activeChannelId: activeChannelClaim && activeChannelClaim.claim_id,
   };
 };

ui/redux/actions/comments.js

@@ -9,8 +9,8 @@ import { selectClaimsByUri, selectMyChannelClaims } from 'redux/selectors/claims
 import { doClaimSearch } from 'redux/actions/claims';
 import { doToast, doSeeNotifications } from 'redux/actions/notifications';
 import {
-  makeSelectMyReactionsForComment,
-  makeSelectOthersReactionsForComment,
+  selectMyReactsForComment,
+  selectOthersReactsForComment,
   selectPendingCommentReacts,
   selectModerationBlockList,
   selectModerationDelegatorsById,
@@ -466,8 +466,8 @@ export function doCommentReact(commentId: string, type: string) {
     }
 
     const reactKey = `${commentId}:${activeChannelClaim.claim_id}`;
-    const myReacts = makeSelectMyReactionsForComment(reactKey)(state);
-    const othersReacts = makeSelectOthersReactionsForComment(reactKey)(state);
+    const myReacts = selectMyReactsForComment(state, reactKey) || [];
+    const othersReacts = selectOthersReactsForComment(state, reactKey) || {};
 
     const signatureData = await channelSignName(activeChannelClaim.claim_id, activeChannelClaim.name);
     if (!signatureData) {

ui/redux/selectors/comments.js

@@ -6,6 +6,8 @@ import { selectBlacklistedOutpointMap, selectFilteredOutpointMap } from 'lbryinc
 import { selectClaimsById, selectMyActiveClaims } from 'redux/selectors/claims';
 import { isClaimNsfw } from 'util/claim';
 
+type State = { comments: CommentsState };
+
 const selectState = (state) => state.comments || {};
 
 export const selectCommentsById = createSelector(selectState, (state) => state.commentById || {});
@@ -13,7 +15,17 @@ export const selectIsFetchingComments = createSelector(selectState, (state) => s
 export const selectIsFetchingCommentsById = createSelector(selectState, (state) => state.isLoadingById);
 export const selectIsFetchingCommentsByParentId = createSelector(selectState, (state) => state.isLoadingByParentId);
 export const selectIsFetchingReacts = createSelector(selectState, (state) => state.isFetchingReacts);
-export const selectOthersReactsById = createSelector(selectState, (state) => state.othersReactsByCommentId);
+
+export const selectMyReacts = (state: State) => state.comments.myReactsByCommentId;
+export const selectMyReactsForComment = (state: State, commentIdChannelId: string) => {
+  // @commentIdChannelId: Format = 'commentId:MyChannelId'
+  return state.comments.myReactsByCommentId && state.comments.myReactsByCommentId[commentIdChannelId];
+};
+
+export const selectOthersReacts = (state: State) => state.comments.othersReactsByCommentId;
+export const selectOthersReactsForComment = (state: State, id: string) => {
+  return state.comments.othersReactsByCommentId && state.comments.othersReactsByCommentId[id];
+};
 
 export const selectPinnedCommentsById = createSelector(selectState, (state) => state.pinnedCommentsById);
 export const makeSelectPinnedCommentsForUri = (uri: string) =>
@@ -177,31 +189,6 @@ export const makeSelectCommentIdsForUri = (uri: string) =>
     return state.byId[claimId];
   });
 
-export const selectMyReactionsByCommentId = createSelector(selectState, (state) => state.myReactsByCommentId);
-
-/**
- * makeSelectMyReactionsForComment
- *
- * @param commentIdChannelId Format = "commentId:MyChannelId".
- */
-export const makeSelectMyReactionsForComment = (commentIdChannelId: string) =>
-  createSelector(selectState, (state) => {
-    if (!state.myReactsByCommentId) {
-      return [];
-    }
-
-    return state.myReactsByCommentId[commentIdChannelId] || [];
-  });
-
-export const makeSelectOthersReactionsForComment = (commentId: string) =>
-  createSelector(selectState, (state) => {
-    if (!state.othersReactsByCommentId) {
-      return {};
-    }
-
-    return state.othersReactsByCommentId[commentId] || {};
-  });
-
 export const selectPendingCommentReacts = createSelector(selectState, (state) => state.pendingCommentReactions);
 
 export const selectSettingsByChannelId = createSelector(selectState, (state) => state.settingsByChannelId);