Merge pull request #4823 from urbit/lf/more-virt-perf

VirtualScroller: performance enhancements

pkg/arvo/app/glob.hoon

@@ -5,7 +5,7 @@
 /-  glob
 /+  default-agent, verb, dbug
 |%
-++  hash  0v3.g6u13.haedt.jt4hd.61ek5.6t30q
+++  hash  0v3.hls3k.gsbae.rm6pr.p6qve.46dh8
 +$  state-0  [%0 hash=@uv glob=(unit (each glob:glob tid=@ta))]
 +$  all-states
   $%  state-0

pkg/arvo/app/landscape/index.html

@@ -24,6 +24,6 @@
     <div id="portal-root"></div>
     <script src="/~landscape/js/channel.js"></script>
     <script src="/~landscape/js/session.js"></script>
-    <script src="/~landscape/js/bundle/index.59e682153138f604d358.js"></script>
+    <script src="/~landscape/js/bundle/index.b253f1f3f824fdeb29d3.js"></script>
   </body>
 </html>

pkg/interface/src/logic/lib/virtualContext.tsx

@@ -43,8 +43,8 @@ export function useVirtualResizeState(s: boolean) {
     [_setState, save]
   );
 
-  useLayoutEffect(() => {
+  useEffect(() => {
-    restore();
+    requestAnimationFrame(restore);
   }, [state]);
 
   return [state, setState] as const;
@@ -58,7 +58,7 @@ export function useVirtualResizeProp(prop: Primitive) {
     save();
   }
 
-  useLayoutEffect(() => {
+  useEffect(() => {
     requestAnimationFrame(restore);
   }, [prop]);
 

pkg/interface/src/logic/reducers/graph-update.ts

@@ -1,5 +1,6 @@
 import _ from 'lodash';
 import BigIntOrderedMap from "@urbit/api/lib/BigIntOrderedMap";
+import produce from 'immer';
 import bigInt, { BigInteger } from "big-integer";
 import useGraphState, { GraphState } from '../state/graph';
 import { reduceState } from '../state/base';
@@ -51,23 +52,18 @@ const keys = (json, state: GraphState): GraphState => {
 const processNode = (node) => {
   //  is empty
   if (!node.children) {
-    node.children = new BigIntOrderedMap();
+    return produce(node, draft => {
-    return node;
+      draft.children = new BigIntOrderedMap();
+    });
   }
 
   //  is graph
-  let converted = new BigIntOrderedMap();
+  return produce(node, draft => {
-  for (let idx in node.children) {
+    draft.children = new BigIntOrderedMap()
-    let item = node.children[idx];
+      .gas(_.map(draft.children, (item, idx) => 
-    let index = bigInt(idx);
+        [bigInt(idx), processNode(item)] as [BigInteger, any]
-    
+      ));
-    converted.set(
+  });
-      index,
-      processNode(item)
-    );
-  }
-  node.children = converted;
-  return node;
 };
 
 
@@ -85,17 +81,10 @@ const addGraph = (json, state: GraphState): GraphState => {
     state.graphTimesentMap[resource] = {};
 
 
-    for (let idx in data.graph) {
+    state.graphs[resource] = state.graphs[resource].gas(Object.keys(data.graph).map(idx => {
-      let item = data.graph[idx];
+      return [bigInt(idx), processNode(data.graph[idx])];
-      let index = bigInt(idx);
+    }));
 
-      let node = processNode(item);
-
-      state.graphs[resource].set(
-        index,
-        node
-      );
-    }
     state.graphKeys.add(resource);
   }
   return state;
@@ -116,7 +105,7 @@ const removeGraph = (json, state: GraphState): GraphState => {
 };
 
 const mapifyChildren = (children) => {
-  return new BigIntOrderedMap(
+  return new BigIntOrderedMap().gas(
     _.map(children, (node, idx) => {
       idx = idx && idx.startsWith('/') ? idx.slice(1) : idx;
       const nd = {...node, children: mapifyChildren(node.children || {}) }; 
@@ -128,8 +117,7 @@ const addNodes = (json, state) => {
   const _addNode = (graph, index, node) => {
     //  set child of graph
     if (index.length === 1) {
-      graph.set(index[0], node);
+      return graph.set(index[0], node);
-      return graph;
     }
 
     // set parent of graph
@@ -138,19 +126,20 @@ const addNodes = (json, state) => {
       console.error('parent node does not exist, cannot add child');
       return graph;
     }
-    parNode.children = _addNode(parNode.children, index.slice(1), node);
+    return graph.set(index[0], produce(parNode, draft => {
-    graph.set(index[0], parNode);
+      draft.children = _addNode(draft.children, index.slice(1), node);
-    return graph;
+    }));
   };
 
   const _remove = (graph, index) => {
     if (index.length === 1) {
-      graph.delete(index[0]);
+      return graph.delete(index[0]);
     } else {
       const child = graph.get(index[0]);
       if (child) {
-        child.children = _remove(child.children, index.slice(1));
+        return graph.set(index[0], produce(child, draft => {
-        graph.set(index[0], child);
+          draft.children = _remove(draft.children, index.slice(1));
+        }));
       }
     }
 
@@ -166,10 +155,9 @@ const addNodes = (json, state) => {
         return bigInt(ind);
       });
 
-      graph = _remove(graph, indexArr);
       delete state.graphTimesentMap[resource][timestamp];
+      return _remove(graph, indexArr);
     }
-
     return graph;
   };
 
@@ -208,11 +196,12 @@ const addNodes = (json, state) => {
       return aArr.length - bArr.length;
     });
 
-    let graph = state.graphs[resource];
-
     indices.forEach((index) => {
       let node = data.nodes[index];
-      graph = _removePending(graph, node.post, resource);
+      const old = state.graphs[resource].size;
+      state.graphs[resource] = _removePending(state.graphs[resource], node.post, resource);
+      const newSize = state.graphs[resource].size;
+
       
       if (index.split('/').length === 0) { return; }
       let indexArr = index.split('/').slice(1).map((ind) => {
@@ -225,17 +214,21 @@ const addNodes = (json, state) => {
         state.graphTimesentMap[resource][node.post['time-sent']] = index;
       }
 
-      node.children = mapifyChildren(node?.children || {});
       
-      graph = _addNode(
+     
-        graph,
+      state.graphs[resource] = _addNode(
+        state.graphs[resource],
         indexArr,
-        node
+        produce(node, draft => {
+          draft.children = mapifyChildren(draft?.children || {});
+        })
       );
+      if(newSize !== old) {
+        console.log(`${resource}, (${old}, ${newSize}, ${state.graphs[resource].size})`);
+      }
       
     });
 
-    state.graphs[resource] = graph;
   }
   return state;
 };
@@ -243,13 +236,15 @@ const addNodes = (json, state) => {
 const removeNodes = (json, state: GraphState): GraphState => {
   const _remove = (graph, index) => {
     if (index.length === 1) {
-        graph.delete(index[0]);
+        return graph.delete(index[0]);
       } else {
         const child = graph.get(index[0]);
         if (child) {
-          _remove(child.children, index.slice(1));
+          return graph.set(index[0], produce(draft => {
-          graph.set(index[0], child);
+            draft.children = _remove(draft.children, index.slice(1))
+          }));
         }
+        return graph;
       }
   };
 
@@ -264,7 +259,7 @@ const removeNodes = (json, state: GraphState): GraphState => {
       let indexArr = index.split('/').slice(1).map((ind) => {
         return bigInt(ind);
       });
-      _remove(state.graphs[res], indexArr);
+      state.graphs[res] = _remove(state.graphs[res], indexArr);
     });
   }
   return state;

pkg/interface/src/logic/reducers/hark-update.ts

@@ -329,9 +329,9 @@ function added(json: any, state: HarkState): HarkState {
     );
     if (arrIdx !== -1) {
       timebox[arrIdx] = { index, notification };
-      state.notifications.set(time, timebox);
+      state.notifications = state.notifications.set(time, timebox);
     } else {
-      state.notifications.set(time, [...timebox, { index, notification }]);
+      state.notifications = state.notifications.set(time, [...timebox, { index, notification }]);
     }
   }
   return state;
@@ -350,7 +350,7 @@ const timebox = (json: any, state: HarkState): HarkState => {
   if (data) {
     const time = makePatDa(data.time);
     if (!data.archive) {
-      state.notifications.set(time, data.notifications);
+      state.notifications = state.notifications.set(time, data.notifications);
     }
   }
   return state;
@@ -403,7 +403,7 @@ function setRead(
     return state;
   }
   timebox[arrIdx].notification.read = read;
-  state.notifications.set(patDa, timebox);
+  state.notifications = state.notifications.set(patDa, timebox);
   return state;
 }
 

pkg/interface/src/logic/state/graph.ts

@@ -128,6 +128,8 @@ const useGraphState = createState<GraphState>('Graph', {
   //   });
   //   graphReducer(node);
   // },
-}, ['graphs', 'graphKeys', 'looseNodes']);
+}, ['graphs', 'graphKeys', 'looseNodes', 'graphTimesentMap']);
+
+window.useGraphState = useGraphState;
 
 export default useGraphState;

pkg/interface/src/views/apps/chat/ChatResource.tsx

@@ -28,9 +28,9 @@ type ChatResourceProps = StoreState & {
   association: Association;
   api: GlobalApi;
   baseUrl: string;
-} & RouteComponentProps;
+};
 
-export function ChatResource(props: ChatResourceProps) {
+function ChatResource(props: ChatResourceProps) {
   const station = props.association.resource;
   const groupPath = props.association.group;
   const groups = useGroupState(state => state.groups);
@@ -40,7 +40,7 @@ export function ChatResource(props: ChatResourceProps) {
   const graphPath = station.slice(7);
   const graph = graphs[graphPath];
   const unreads = useHarkState(state => state.unreads);
-  const unreadCount = unreads.graph?.[station]?.['/']?.unreads || 0;
+  const unreadCount = unreads.graph?.[station]?.['/']?.unreads as number || 0;
   const graphTimesentMap = useGraphState(state => state.graphTimesentMap);
   const [,, owner, name] = station.split('/');
   const ourContact = contacts?.[`~${window.ship}`];
@@ -48,7 +48,7 @@ export function ChatResource(props: ChatResourceProps) {
   const canWrite = isWriter(group, station);
 
   useEffect(() => {
-    const count = 100 + unreadCount;
+    const count = Math.min(400, 100 + unreadCount);
     props.api.graph.getNewest(owner, name, count);
   }, [station]);
 
@@ -165,10 +165,9 @@ export function ChatResource(props: ChatResourceProps) {
       {dragging && <SubmitDragger />}
       <ChatWindow
         key={station}
-        history={props.history}
         graph={graph}
         graphSize={graph.size}
-        unreadCount={unreadCount}
+        unreadCount={unreadCount as number}
         showOurContact={ !showBanner && hasLoadedAllowed }
         association={props.association}
         pendingSize={Object.keys(graphTimesentMap[graphPath] || {}).length}
@@ -196,3 +195,8 @@ export function ChatResource(props: ChatResourceProps) {
     </Col>
   );
 }
+
+ChatResource.whyDidYouRender = true;
+
+export { ChatResource };
+

pkg/interface/src/views/apps/chat/components/ChatMessage.tsx

@@ -3,6 +3,7 @@ import bigInt from 'big-integer';
 import React, {
   useState,
   useEffect,
+  useMemo,
   useRef,
   Component,
   PureComponent,
@@ -40,11 +41,12 @@ import styled from 'styled-components';
 import useLocalState from '~/logic/state/local';
 import useSettingsState, { selectCalmState } from '~/logic/state/settings';
 import Timestamp from '~/views/components/Timestamp';
-import useContactState from '~/logic/state/contact';
+import useContactState, {useContact} from '~/logic/state/contact';
 import { useIdlingState } from '~/logic/lib/idling';
 import ProfileOverlay from '~/views/components/ProfileOverlay';
 import {useCopy} from '~/logic/lib/useCopy';
 import {GraphContentWide} from '~/views/landscape/components/Graph/GraphContentWide';
+import {Contact} from '@urbit/api';
 
 
 export const DATESTAMP_FORMAT = '[~]YYYY.M.D';
@@ -80,7 +82,7 @@ export const DayBreak = ({ when, shimTop = false }: DayBreakProps) => (
 );
 
 export const UnreadMarker = React.forwardRef(
-  ({ dayBreak, when, api, association }, ref) => {
+  ({ dayBreak, when, api, association }: any, ref) => {
     const [visible, setVisible] = useState(false);
     const idling = useIdlingState();
     const dismiss = useCallback(() => {
@@ -141,7 +143,7 @@ const MessageActionItem = (props) => {
   );
 };
 
-const MessageActions = ({ api, onReply, association, history, msg, group }) => {
+const MessageActions = ({ api, onReply, association, msg, group }) => {
   const isAdmin = () => group.tags.role.admin.has(window.ship);
   const isOwn = () => msg.author === window.ship;
   const { doCopy, copyDisplay } = useCopy(`web+urbitgraph://group${association.group.slice(5)}/graph${association.resource.slice(5)}${msg.index}`, 'Copy Message Link');
@@ -241,29 +243,18 @@ interface ChatMessageProps {
   className?: string;
   isPending: boolean;
   style?: unknown;
-  scrollWindow: HTMLDivElement;
   isLastMessage?: boolean;
   unreadMarkerRef: React.RefObject<HTMLDivElement>;
-  history: unknown;
   api: GlobalApi;
   highlighted?: boolean;
   renderSigil?: boolean;
   hideHover?: boolean;
   innerRef: (el: HTMLDivElement | null) => void;
   onReply?: (msg: Post) => void;
+  showOurContact: boolean;
 }
 
-class ChatMessage extends Component<ChatMessageProps> {
+function ChatMessage(props: ChatMessageProps) {
-  private divRef: React.RefObject<HTMLDivElement>;
-
-  constructor(props) {
-    super(props);
-    this.divRef = React.createRef();
-  }
-
-  componentDidMount() {}
-
-  render() {
   let { highlighted } = this.props;
   const {
     msg,
@@ -275,15 +266,20 @@ class ChatMessage extends Component<ChatMessageProps> {
     className = '',
     isPending,
     style,
-      scrollWindow,
     isLastMessage,
     unreadMarkerRef,
-      history,
     api,
     showOurContact,
     fontSize,
     hideHover
-    } = this.props;
+  } = props;
+
+  let onReply = props?.onReply ?? (() => {});
+  const transcluded = props?.transcluded ?? 0;
+  const renderSigil = props.renderSigil ?? (Boolean(nextMsg && msg.author !== nextMsg.author) ||
+        !nextMsg ||
+        msg.number === 1
+    );
 
     const ourMention = msg?.contents?.some((e) => {
       return e?.mention && e?.mention === window.ship;
@@ -295,46 +291,35 @@ class ChatMessage extends Component<ChatMessageProps> {
       }
     }
 
-    let onReply = this.props?.onReply ?? (() => {});
+  const date = useMemo(() => daToUnix(bigInt(msg.index.split('/')[1])), [msg.index]);
-    const transcluded = this.props?.transcluded ?? 0;
+  const nextDate = useMemo(() => nextMsg ? (
-    let { renderSigil } = this.props;
-
-    if (renderSigil === undefined) {
-      renderSigil = Boolean(
-        (nextMsg && msg.author !== nextMsg.author) ||
-          !nextMsg ||
-          msg.number === 1
-      );
-    }
-
-    const date = daToUnix(bigInt(msg.index.split('/')[1]));
-    const nextDate = nextMsg ? (
     daToUnix(bigInt(nextMsg.index.split('/')[1]))
-    ) : null;
+  ) : null,
+    [nextMsg]
+  );
 
-    const dayBreak =
+  const dayBreak = useMemo(() =>
-      nextMsg &&
+    nextDate &&
     new Date(date).getDate() !==
-      new Date(nextDate).getDate();
+    new Date(nextDate).getDate()
+  , [nextDate, date])
 
   const containerClass = `${isPending ? 'o-40' : ''} ${className}`;
 
-    const timestamp = moment
+  const timestamp = useMemo(() => moment
     .unix(date / 1000)
-      .format(renderSigil ? 'h:mm A' : 'h:mm');
+    .format(renderSigil ? 'h:mm A' : 'h:mm'),
+    [date, renderSigil]
+  );
 
   const messageProps = {
     msg,
     timestamp,
     association,
     group,
-      style,
-      containerClass,
     isPending,
     showOurContact,
-      history,
     api,
-      scrollWindow,
     highlighted,
     fontSize,
     hideHover,
@@ -342,13 +327,24 @@ class ChatMessage extends Component<ChatMessageProps> {
     onReply
   };
 
+  const message = useMemo(() => (
+    <Message
+      msg={msg}
+      timestamp={timestamp}
+      timestampHover={!renderSigil}
+      api={api}
+      transcluded={transcluded}
+      showOurContact={showOurContact}
+    />
+  ), [renderSigil, msg, timestamp, api, transcluded, showOurContact]);
+
   const unreadContainerStyle = {
     height: isLastRead ? '2rem' : '0'
   };
 
   return (
     <Box
-        ref={this.props.innerRef}
+      ref={props.innerRef}
       pt={renderSigil ? 2 : 0}
       width="100%"
       pb={isLastMessage ? '20px' : 0}
@@ -361,11 +357,11 @@ class ChatMessage extends Component<ChatMessageProps> {
       {renderSigil ? (
         <MessageWrapper {...messageProps}>
           <MessageAuthor pb={1} {...messageProps} />
-            <Message pl={'44px'} pr={4} {...messageProps} />
+          {message}
         </MessageWrapper>
       ) : (
         <MessageWrapper {...messageProps}>
-            <Message pl={'44px'} pr={4} timestampHover {...messageProps} />
+          {message}
         </MessageWrapper>
       )}
       <Box style={unreadContainerStyle}>
@@ -381,40 +377,34 @@ class ChatMessage extends Component<ChatMessageProps> {
       </Box>
     </Box>
   );
-  }
 }
 
-export default React.forwardRef((props, ref) => (
+export default React.forwardRef((props: Omit<ChatMessageProps, 'innerRef'>, ref: any) => (
   <ChatMessage {...props} innerRef={ref} />
 ));
 
 export const MessageAuthor = ({
   timestamp,
   msg,
-  group,
   api,
-  history,
-  scrollWindow,
   showOurContact,
-  ...rest
 }) => {
   const osDark = useLocalState((state) => state.dark);
 
   const theme = useSettingsState((s) => s.display.theme);
   const dark = theme === 'dark' || (theme === 'auto' && osDark);
-  const contacts = useContactState((state) => state.contacts);
+  let contact: Contact | null = useContact(`~${msg.author}`);
 
   const date = daToUnix(bigInt(msg.index.split('/')[1]));
 
   const datestamp = moment
     .unix(date / 1000)
     .format(DATESTAMP_FORMAT);
-  const contact =
+  contact =
     ((msg.author === window.ship && showOurContact) ||
-      msg.author !== window.ship) &&
+      msg.author !== window.ship)
-    `~${msg.author}` in contacts
+      ? contact
-      ? contacts[`~${msg.author}`]
+      : null;
-      : undefined;
 
   const showNickname = useShowNickname(contact);
   const { hideAvatars } = useSettingsState(selectCalmState);
@@ -467,7 +457,7 @@ export const MessageAuthor = ({
       </Box>
     );
   return (
-    <Box display='flex' alignItems='flex-start' {...rest}>
+    <Box display='flex' alignItems='flex-start'>
       <Box
        height={24}
         pr={2}
@@ -519,20 +509,20 @@ export const MessageAuthor = ({
   );
 };
 
-export const Message = ({
+type MessageProps = { timestamp: string; timestampHover: boolean; }
+  & Pick<ChatMessageProps, "msg" | "api" | "transcluded" | "showOurContact">
+
+export const Message = React.memo(({
   timestamp,
   msg,
-  group,
   api,
-  scrollWindow,
   timestampHover,
   transcluded,
-  showOurContact,
+  showOurContact
-  ...rest
+}: MessageProps) => {
-}) => {
   const { hovering, bind } = useHovering();
   return (
-    <Box width="100%" position='relative' {...rest}>
+    <Box pl="44px" width="100%" position='relative'>
       {timestampHover ? (
         <Text
           display={hovering ? 'block' : 'none'}
@@ -559,7 +549,9 @@ export const Message = ({
       />
     </Box>
   );
-};
+});
+
+Message.displayName = 'Message';
 
 export const MessagePlaceholder = ({
   height,

pkg/interface/src/views/apps/chat/components/ChatWindow.tsx

@@ -1,4 +1,4 @@
-import React, { Component } from 'react';
+import React, { useEffect, Component, useRef, useState, useCallback } from 'react';
 import { RouteComponentProps } from 'react-router-dom';
 import _ from 'lodash';
 import bigInt, { BigInteger } from 'big-integer';
@@ -30,10 +30,13 @@ const DEFAULT_BACKLOG_SIZE = 100;
 const IDLE_THRESHOLD = 64;
 const MAX_BACKLOG_SIZE = 1000;
 
-type ChatWindowProps = RouteComponentProps<{
+const getCurrGraphSize = (ship: string, name: string) => {
-  ship: Patp;
+  const { graphs } = useGraphState.getState();
-  station: string;
+  const graph = graphs[`${ship}/${name}`];
-}> & {
+  return graph.size;
+};
+
+type ChatWindowProps = {
   unreadCount: number;
   graph: Graph;
   graphSize: number;
@@ -44,6 +47,8 @@ type ChatWindowProps = RouteComponentProps<{
   api: GlobalApi;
   scrollTo?: BigInteger;
   onReply: (msg: Post) => void;
+  pendingSize?: number;
+  showOurContact: boolean;
 };
 
 interface ChatWindowState {
@@ -55,6 +60,7 @@ interface ChatWindowState {
 
 const virtScrollerStyle = { height: '100%' };
 
+
 class ChatWindow extends Component<
   ChatWindowProps,
   ChatWindowState
@@ -81,6 +87,7 @@ class ChatWindow extends Component<
     this.handleWindowBlur = this.handleWindowBlur.bind(this);
     this.handleWindowFocus = this.handleWindowFocus.bind(this);
     this.stayLockedIfActive = this.stayLockedIfActive.bind(this);
+    this.fetchMessages = this.fetchMessages.bind(this);
 
     this.virtualList = null;
     this.unreadMarkerRef = React.createRef();
@@ -109,9 +116,11 @@ class ChatWindow extends Component<
     }
     const unreadIndex = graph.keys()[unreadCount];
     if (!unreadIndex || unreadCount === 0) {
+      if(state.unreadIndex.neq(bigInt.zero)) {
         this.setState({
           unreadIndex: bigInt.zero
         });
+      }
       return;
     }
     this.setState({
@@ -122,7 +131,7 @@ class ChatWindow extends Component<
   dismissedInitialUnread() {
     const { unreadCount, graph } = this.props;
   
-    return this.state.unreadIndex.neq(bigInt.zero) &&
+    return this.state.unreadIndex.eq(bigInt.zero) ? unreadCount > graph.size : 
     this.state.unreadIndex.neq(graph.keys()?.[unreadCount]?.[0] ?? bigInt.zero); 
   }
 
@@ -138,7 +147,7 @@ class ChatWindow extends Component<
   }
 
   componentDidUpdate(prevProps: ChatWindowProps, prevState) {
-    const { history, graph, unreadCount, graphSize, station } = this.props;
+    const { graph, unreadCount, graphSize, station } = this.props;
     if(unreadCount === 0 && prevProps.unreadCount !== unreadCount) {
       this.unreadSet = true;
     }
@@ -195,31 +204,35 @@ class ChatWindow extends Component<
     this.props.api.hark.markCountAsRead(association, '/', 'message');
   }
 
-  setActive = () => { 
-    if(this.state.idle) {
-      this.setState({ idle: false });
-    }
-  }
 
-  fetchMessages = async (newer: boolean): Promise<boolean> => {
+  async fetchMessages(newer: boolean): Promise<boolean> {
     const { api, station, graph } = this.props;
     const pageSize = 100;
 
     const [, , ship, name] = station.split('/');
     const expectedSize = graph.size + pageSize;
     if (newer) {
-      const [index] = graph.peekLargest()!;
+      const index = graph.peekLargest()?.[0];
+      if(!index) {
+        console.log(`no index for: ${graph}`);
+        return true;
+      }
       await api.graph.getYoungerSiblings(
         ship,
         name,
         pageSize,
         `/${index.toString()}`
       );
-      return expectedSize !== graph.size;
+      return expectedSize !== getCurrGraphSize(ship.slice(1), name);
     } else {
-      const [index] = graph.peekSmallest()!;
+      console.log('x');
+      const index = graph.peekSmallest()?.[0];
+      if(!index) {
+        console.log(`no index for: ${graph}`);
+        return true;
+      }
       await api.graph.getOlderSiblings(ship, name, pageSize, `/${index.toString()}`);
-      const done = expectedSize !== graph.size;
+      const done = expectedSize !== getCurrGraphSize(ship.slice(1), name);
       if(done) {
         this.calculateUnreadIndex();
       }
@@ -238,12 +251,9 @@ class ChatWindow extends Component<
     const {
       api,
       association,
-      group,
       showOurContact,
       graph,
-      history,
+      group,
-      groups,
-      associations,
       onReply
     } = this.props;
     const { unreadMarkerRef } = this;
@@ -252,10 +262,8 @@ class ChatWindow extends Component<
       group,
       showOurContact,
       unreadMarkerRef,
-      history,
       api,
-      groups,
+      group,
-      associations,
       onReply
     };
 
@@ -275,10 +283,10 @@ class ChatWindow extends Component<
       graph.peekLargest()?.[0] ?? bigInt.zero
     );
     const highlighted = index.eq(this.props.scrollTo ?? bigInt.zero);
-    const keys = graph.keys().reverse();
+    const keys = graph.keys();
     const graphIdx = keys.findIndex((idx) => idx.eq(index));
-    const prevIdx = keys[graphIdx + 1];
+    const prevIdx = keys[graphIdx - 1];
-    const nextIdx = keys[graphIdx - 1];
+    const nextIdx = keys[graphIdx + 1];
     const isLastRead: boolean = this.state.unreadIndex.eq(index);
     const props = {
       highlighted,
@@ -308,12 +316,8 @@ class ChatWindow extends Component<
       association,
       group,
       graph,
-      history,
-      groups,
-      associations,
       showOurContact,
-      pendingSize,
+      pendingSize = 0,
-      onReply,
     } = this.props;
 
     const unreadMarkerRef = this.unreadMarkerRef;
@@ -321,16 +325,10 @@ class ChatWindow extends Component<
       association,
       group,
       unreadMarkerRef,
-      history,
       api,
-      associations
     };
     const unreadMsg = graph.get(this.state.unreadIndex);
     
-    // hack to force a re-render when we toggle showing contact
-    const contactsModified =
-      showOurContact ? 0 : 100;
-
     return (
       <Col height='100%' overflow='hidden' position='relative'>
         { this.dismissedInitialUnread() && 
@@ -353,12 +351,11 @@ class ChatWindow extends Component<
           offset={unreadCount}
           origin='bottom'
           style={virtScrollerStyle}
-          onStartReached={this.setActive}
           onBottomLoaded={this.onBottomLoaded}
           onScroll={this.onScroll}
           data={graph}
           size={graph.size}
-          pendingSize={pendingSize + contactsModified}
+          pendingSize={pendingSize}
           id={association.resource}
           averageHeight={22}
           renderer={this.renderer}
@@ -369,8 +366,5 @@ class ChatWindow extends Component<
   }
 }
 
-export default withState(ChatWindow, [
+
-  [useGroupState, ['groups']],
+export default ChatWindow
-  [useMetadataState, ['associations']],
-  [useGraphState, ['pendingSize']]
-]);

pkg/interface/src/views/apps/chat/components/unread-notice.js

@@ -8,22 +8,11 @@ import Timestamp from '~/views/components/Timestamp';
 export const UnreadNotice = (props) => {
   const { unreadCount, unreadMsg, dismissUnread, onClick } = props;
 
-  if (!unreadMsg || unreadCount === 0) {
+  if (unreadCount === 0) {
     return null;
   }
 
-  const stamp = moment.unix(unreadMsg.post['time-sent'] / 1000);
+  const stamp = unreadMsg && moment.unix(unreadMsg.post['time-sent'] / 1000);
-
-  let datestamp = moment
-    .unix(unreadMsg.post['time-sent'] / 1000)
-    .format('YYYY.M.D');
-  const timestamp = moment
-    .unix(unreadMsg.post['time-sent'] / 1000)
-    .format('HH:mm');
-
-  if (datestamp === moment().format('YYYY.M.D')) {
-    datestamp = null;
-  }
 
   return (
     <Box
@@ -52,15 +41,20 @@ export const UnreadNotice = (props) => {
               whiteSpace='pre'
               overflow='hidden'
               display='flex'
-              cursor='pointer'
+              cursor={unreadMsg ? 'pointer' : null}
               onClick={onClick}
             >
-              {unreadCount} new message{unreadCount > 1 ? 's' : ''} since{' '}
+              {unreadCount} new message{unreadCount > 1 ? 's' : ''}
+              {unreadMsg && (
+                <>
+                {' '}since{' '}
                 <Timestamp stamp={stamp} color='black' date={true} fontSize={1} />
+                </>
+              )}
             </Text>
             <Icon
               icon='X'
-              ml='4'
+              ml={unreadMsg ? 4 : 1}
               color='black'
               cursor='pointer'
               textAlign='right'

pkg/interface/src/views/apps/links/LinkResource.tsx

@@ -23,7 +23,7 @@ type LinkResourceProps = StoreState & {
   association: Association;
   api: GlobalApi;
   baseUrl: string;
-} & RouteComponentProps;
+};
 
 export function LinkResource(props: LinkResourceProps) {
   const {

pkg/interface/src/views/apps/links/LinkWindow.tsx

@@ -6,7 +6,7 @@ import React, {
   Component,
 } from "react";
 
-import { Col, Text } from "@tlon/indigo-react";
+import { Box, Col, Text } from "@tlon/indigo-react";
 import bigInt from "big-integer";
 import { Association, Graph, Unreads, Group, Rolodex } from "@urbit/api";
 
@@ -48,7 +48,7 @@ class LinkWindow extends Component<LinkWindowProps, {}> {
     return isWriter(group, association.resource);
   }
 
-  renderItem = ({ index, scrollWindow }) => {
+  renderItem = React.forwardRef(({ index, scrollWindow }, ref) => {
     const { props } = this;
     const { association, graph, api } = props;
     const [, , ship, name] = association.resource.split("/");
@@ -80,12 +80,14 @@ class LinkWindow extends Component<LinkWindowProps, {}> {
               api={api}
             />
           </Col>
-          <LinkItem {...linkProps} />
+          <LinkItem ref={ref} {...linkProps} />
         </React.Fragment>
       );
     }
-    return <LinkItem key={index.toString()} {...linkProps} />;
+    return <Box ref={ref}>
-  };
+      <LinkItem ref={ref} key={index.toString()} {...linkProps} />;
+    </Box>
+  });
 
   render() {
     const { graph, api, association } = this.props;

pkg/interface/src/views/apps/links/components/LinkItem.tsx

@@ -19,7 +19,7 @@ interface LinkItemProps {
   node: GraphNode;
   association: Association;
   resource: string; api: GlobalApi; group: Group; path: string; }
-export const LinkItem = (props: LinkItemProps): ReactElement => {
+export const LinkItem = React.forwardRef((props: LinkItemProps, ref): ReactElement => {
   const {
     association,
     node,
@@ -30,7 +30,6 @@ export const LinkItem = (props: LinkItemProps): ReactElement => {
     ...rest
   } = props;
 
-  const ref = useRef<HTMLDivElement | null>(null);
   const remoteRef = useRef<typeof RemoteContent | null>(null);
   const index = node.post.index.split('/')[1];
 
@@ -210,5 +209,5 @@ export const LinkItem = (props: LinkItemProps): ReactElement => {
 
     </Row>
   </Box>);
-};
+});
 

pkg/interface/src/views/apps/publish/PublishResource.tsx

@@ -11,7 +11,7 @@ type PublishResourceProps = StoreState & {
   association: Association;
   api: GlobalApi;
   baseUrl: string;
-} & RouteComponentProps;
+};
 
 export function PublishResource(props: PublishResourceProps) {
   const { association, api, baseUrl, notebooks } = props;

pkg/interface/src/views/components/VirtualScroller.tsx

@@ -1,4 +1,4 @@
-import React, { Component, useCallback } from 'react';
+import React, { Component, useCallback, SyntheticEvent } from 'react';
 import _ from 'lodash';
 import normalizeWheel from 'normalize-wheel';
 import bigInt, { BigInteger } from 'big-integer';
@@ -76,7 +76,7 @@ interface VirtualScrollerProps<T> {
 }
 
 interface VirtualScrollerState<T> {
-  visibleItems: BigIntOrderedMap<T>;
+  visibleItems: BigInteger[];
   scrollbar: number;
   loaded: {
     top: boolean;
@@ -91,10 +91,9 @@ const log = (level: LogLevel, message: string) => {
   if(logLevel.includes(level)) {
     console.log(`[${level}]: ${message}`);
   }
-
 }
 
-const ZONE_SIZE = IS_IOS ? 10 : 40;
+const ZONE_SIZE = IS_IOS ? 10 : 80;
 
 
 // nb: in this file, an index refers to a BigInteger and an offset refers to a
@@ -114,7 +113,7 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
   /**
    * A map of child refs, used to calculate scroll position
    */
-  private childRefs = new BigIntOrderedMap<HTMLElement>();
+  private childRefs = new Map<string, HTMLElement>();
   /**
    * A set of child refs which have been unmounted
    */
@@ -149,7 +148,7 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
   constructor(props: VirtualScrollerProps<T>) {
     super(props);
     this.state = {
-      visibleItems: new BigIntOrderedMap(),
+      visibleItems: [],
       scrollbar: 0,
       loaded: {
         top: false,
@@ -160,10 +159,11 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
     this.updateVisible = this.updateVisible.bind(this);
 
     this.invertedKeyHandler = this.invertedKeyHandler.bind(this);
-    this.onScroll = IS_IOS ? _.debounce(this.onScroll.bind(this), 400) : this.onScroll.bind(this);
+    this.onScroll = IS_IOS ? _.debounce(this.onScroll.bind(this), 200) : this.onScroll.bind(this);
     this.scrollKeyMap = this.scrollKeyMap.bind(this);
     this.setWindow = this.setWindow.bind(this);
     this.restore = this.restore.bind(this);
+    this.startOffset = this.startOffset.bind(this);
   }
 
   componentDidMount() {
@@ -181,7 +181,7 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
     }
     [...this.orphans].forEach(o => {
       const index = bigInt(o);
-      this.childRefs.delete(index);
+      this.childRefs.delete(index.toString());
     });
     this.orphans.clear();
   };
@@ -206,13 +206,10 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
 
   componentDidUpdate(prevProps: VirtualScrollerProps<T>, _prevState: VirtualScrollerState<T>) {
     const { id, size, data, offset, pendingSize } = this.props;
-    const { visibleItems } = this.state;
 
     if(size !== prevProps.size || pendingSize !== prevProps.pendingSize) {
-      if(this.scrollLocked && visibleItems?.peekLargest() && data?.peekLargest()) {
+      if(this.scrollLocked) {
-        if(!visibleItems.peekLargest()[0].eq(data.peekLargest()[0])) {
         this.updateVisible(0);
-        }
         this.resetScroll();
       }
     }
@@ -228,11 +225,13 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
   }
 
   startOffset() {
-    const startIndex = this.state?.visibleItems?.peekLargest()?.[0];
+    const { data } = this.props;
+    const startIndex = this.state.visibleItems?.[0];
     if(!startIndex) {
       return 0;
     }
-    const offset = [...this.props.data].findIndex(([i]) => i.eq(startIndex))
+    const dataList = Array.from(data);
+    const offset = dataList.findIndex(([i]) => i.eq(startIndex))
     if(offset === -1) {
       // TODO: revisit when we remove nodes for any other reason than
       // pending indices being removed
@@ -252,19 +251,17 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
     log('reflow', `from: ${this.startOffset()} to: ${newOffset}`);
 
     const { data, onCalculateVisibleItems } = this.props;
-    const visibleItems = new BigIntOrderedMap<any>(
+    const visibleItems = data.keys().slice(newOffset, newOffset + this.pageSize);
-      [...data].slice(newOffset, newOffset + this.pageSize)
-    );
 
     this.save();
 
     this.setState({
       visibleItems,
-    }, () => {
+    });
     requestAnimationFrame(() => {
       this.restore();
     });
-    });
+
   }
 
   scrollKeyMap(): Map<string, number> {
@@ -296,7 +293,6 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
   setWindow(element) {
     if (!element)
       return;
-    console.log('resetting window');
     this.save();
 
     if (this.window) {
@@ -309,8 +305,8 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
     const { averageHeight } = this.props;
 
     this.window = element;
-    this.pageSize = Math.floor(element.offsetHeight / Math.floor(averageHeight / 5.5));
+    this.pageSize = Math.floor(element.offsetHeight / Math.floor(averageHeight / 2));
-    this.pageDelta = Math.floor(this.pageSize / 3);
+    this.pageDelta = Math.floor(this.pageSize / 4);
     if (this.props.origin === 'bottom') {
        element.addEventListener('wheel', (event) => {
         event.preventDefault();
@@ -356,7 +352,7 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
     }
   };
 
-  onScroll(event: UIEvent) {
+  onScroll(event: SyntheticEvent<HTMLElement, ScrollEvent>) {
     this.updateScroll();
     if(!this.window) {
       // bail if we're going to adjust scroll anyway
@@ -371,6 +367,8 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
     const { scrollTop, scrollHeight } = this.window;
 
     const startOffset = this.startOffset();
+
+    const scrollEnd = scrollTop + windowHeight;
     if (scrollTop < ZONE_SIZE) {
       log('scroll', `Entered start zone ${scrollTop}`);
       if (startOffset === 0) {
@@ -417,17 +415,23 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
     }
       if(this.scrollLocked) {
         this.resetScroll();
+      requestAnimationFrame(() => {
         this.savedIndex = null;
         this.savedDistance = 0;
         this.saveDepth--;
+      });
       return;
     }
 
-    let ref = this.childRefs.get(this.savedIndex)
+    let ref = this.childRefs.get(this.savedIndex.toString())
     if(!ref) {
       return;
     }
-    const newScrollTop = this.window.scrollHeight - ref.offsetTop - this.savedDistance;
+
+    const newScrollTop = this.props.origin === 'top'
+      ? this.savedDistance + ref.offsetTop
+      : this.window.scrollHeight - ref.offsetTop - this.savedDistance;
+
 
     this.window.scrollTo(0, newScrollTop);
     requestAnimationFrame(() => {
@@ -435,10 +439,11 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
         this.savedDistance = 0;
         this.saveDepth--;
       });
+
   }
 
   scrollToIndex = (index: BigInteger) => {
-    let ref = this.childRefs.get(index);
+    let ref = this.childRefs.get(index.toString());
     if(!ref) {
       const offset = [...this.props.data].findIndex(([idx]) => idx.eq(index));
       if(offset === -1) {
@@ -446,7 +451,7 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
       }
       this.updateVisible(Math.max(offset - this.pageDelta, 0));
       requestAnimationFrame(() => {
-        ref = this.childRefs.get(index);
+        ref = this.childRefs.get(index.toString());
         this.savedIndex = null;
         this.savedDistance = 0;
         this.saveDepth = 0;
@@ -467,17 +472,20 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
       return;
     }
     if(this.saveDepth !== 0) {
-      console.log('bail', 'deep save');
       return;
     }
 
-    this.saveDepth++;
+    log('scroll', 'saving...');
 
-    let bottomIndex: BigInteger | null = null;
+    this.saveDepth++;
+    const { visibleItems } = this.state;
+
+    let bottomIndex = visibleItems[visibleItems.length - 1];
     const { scrollTop, scrollHeight } = this.window;
-    const topSpacing = scrollHeight - scrollTop;
+    const topSpacing = this.props.origin === 'top' ? scrollTop : scrollHeight - scrollTop;
-    [...Array.from(this.state.visibleItems)].reverse().forEach(([index, datum]) => {
+    const items = this.props.origin === 'top' ? visibleItems : [...visibleItems].reverse();
-      const el = this.childRefs.get(index);
+    items.forEach((index) => {
+      const el = this.childRefs.get(index.toString());
       if(!el) {
         return;
       }
@@ -490,20 +498,22 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
     if(!bottomIndex) {
       // weird, shouldn't really happen
       this.saveDepth--;
+      log('bail', 'no index found');
       return;
     }
 
     this.savedIndex = bottomIndex;
-    const ref = this.childRefs.get(bottomIndex)!;
+    const ref = this.childRefs.get(bottomIndex.toString())!;
     const { offsetTop } = ref;
     this.savedDistance = topSpacing - offsetTop
   }
 
-  shiftLayout = { save: this.save.bind(this), restore: this.restore.bind(this) };
+  // disabled until we work out race conditions with loading new nodes
+  shiftLayout = { save: () => {}, restore: () => {} };
 
   setRef = (element: HTMLElement | null, index: BigInteger) => {
     if(element) {
-      this.childRefs.set(index, element);
+      this.childRefs.set(index.toString(), element);
       this.orphans.delete(index.toString());
     } else {
       this.orphans.add(index.toString());
@@ -525,12 +535,11 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
 
     const isTop = origin === 'top';
 
-    const indexesToRender = isTop ? visibleItems.keys() : visibleItems.keys().reverse();
-
     const transform = isTop ? 'scale3d(1, 1, 1)' : 'scale3d(1, -1, 1)';
+    const children = isTop ? visibleItems : [...visibleItems].reverse();
 
-    const atStart = (this.props.data.peekLargest()?.[0] ?? bigInt.zero).eq(visibleItems.peekLargest()?.[0] || bigInt.zero);
+    const atStart = (this.props.data.peekLargest()?.[0] ?? bigInt.zero).eq(visibleItems?.[0] || bigInt.zero);
-    const atEnd = this.state.loaded.top;
+    const atEnd = (this.props.data.peekSmallest()?.[0] ?? bigInt.zero).eq(visibleItems?.[visibleItems.length -1 ] || bigInt.zero);
 
     return (
       <>
@@ -542,7 +551,7 @@ export default class VirtualScroller<T> extends Component<VirtualScrollerProps<T
             <LoadingSpinner />
           </Center>)}
           <VirtualContext.Provider value={this.shiftLayout}>
-            {indexesToRender.map(index => (
+            {children.map(index => (
               <VirtualChild
                 key={index.toString()}
                 setRef={this.setRef}
@@ -575,8 +584,10 @@ function VirtualChild(props: VirtualChildProps) {
 
   const ref = useCallback((el: HTMLElement | null) => {
     setRef(el, props.index);
-  }, [setRef, props.index])
+  //  VirtualChild should always be keyed on the index, so the index should be
+  //  valid for the entire lifecycle of the component, hence no dependencies
+  }, []);
 
-  return (<Renderer ref={ref} {...rest} />);
+  return <Renderer ref={ref} {...rest} />
 };
 

pkg/interface/src/views/landscape/components/GroupsPane.tsx

@@ -124,7 +124,6 @@ export function GroupsPane(props: GroupsPaneProps) {
             >
               <Resource
                 {...props}
-                {...routeProps}
                 association={association}
                 baseUrl={baseUrl}
               />

pkg/interface/src/views/landscape/components/Home/Post/PostFeed.js

@@ -2,7 +2,7 @@ import React from 'react';
 import bigInt from 'big-integer';
 import VirtualScroller from "~/views/components/VirtualScroller";
 import PostItem from './PostItem/PostItem';
-import { Col } from '@tlon/indigo-react';
+import { Col, Box } from '@tlon/indigo-react';
 import { resourceFromPath } from '~/logic/lib/group';
 
 
@@ -15,7 +15,12 @@ export class PostFeed extends React.Component {
     super(props);
 
     this.isFetching = false;
-    this.renderItem = React.forwardRef(({ index, scrollWindow }, ref) => {
+
+    this.fetchPosts = this.fetchPosts.bind(this);
+    this.doNotFetch = this.doNotFetch.bind(this);
+  }
+
+  renderItem = React.forwardRef(({ index, scrollWindow }, ref) => {
     const {
       graph,
       graphPath,
@@ -46,13 +51,13 @@ export class PostFeed extends React.Component {
         <React.Fragment key={index.toString()}>
           <Col
             key={index.toString()}
+            ref={ref}
             mb="3"
             width="100%"
             flexShrink={0}
           >
             <PostItem
               key={parentNode.post.index}
-                ref={ref}
               parentPost={grandparentNode?.post}
               node={parentNode}
               parentNode={grandparentNode}
@@ -69,7 +74,6 @@ export class PostFeed extends React.Component {
             />
           </Col>
           <PostItem
-              ref={ref}
             node={node}
             graphPath={graphPath}
             association={association}
@@ -88,9 +92,8 @@ export class PostFeed extends React.Component {
     }
 
     return (
+      <Box key={index.toString()} ref={ref}>
       <PostItem
-          key={index.toString()}
-          ref={ref}
         node={node}
         graphPath={graphPath}
         association={association}
@@ -104,12 +107,10 @@ export class PostFeed extends React.Component {
         vip={vip}
         group={group}
       />
+      </Box>
     );
   });
 
-    this.fetchPosts = this.fetchPosts.bind(this);
-    this.doNotFetch = this.doNotFetch.bind(this);
-  }
 
   async fetchPosts(newer) {
     const { graph, graphPath, api } = this.props;

pkg/interface/src/views/landscape/components/Resource.tsx

@@ -15,12 +15,14 @@ import useGroupState from '~/logic/state/group';
 import useContactState from '~/logic/state/contact';
 import useHarkState from '~/logic/state/hark';
 import useMetadataState from '~/logic/state/metadata';
+import {Workspace} from '~/types';
 
 type ResourceProps = StoreState & {
   association: Association;
   api: GlobalApi;
   baseUrl: string;
-} & RouteComponentProps;
+  workspace: Workspace;
+};
 
 export function Resource(props: ResourceProps): ReactElement {
   const { association, api, notificationsGraphConfig } = props;

pkg/npm/api/lib/BigIntOrderedMap.ts

@@ -1,6 +1,10 @@
-import { immerable } from 'immer';
+import produce, { immerable, castImmutable, castDraft, setAutoFreeze, enablePatches } from 'immer';
 import bigInt, { BigInteger } from "big-integer";
 
+setAutoFreeze(false);
+
+enablePatches();
+
 function sortBigInt(a: BigInteger, b: BigInteger) {
   if (a.lt(b)) {
     return 1;
@@ -11,19 +15,18 @@ function sortBigInt(a: BigInteger, b: BigInteger) {
   }
 }
 export default class BigIntOrderedMap<V> implements Iterable<[BigInteger, V]> {
-  private root: Record<string, V> = {}
+  root: Record<string, V> = {}
-  private cachedIter: [BigInteger, V][] | null = null;
+  cachedIter: [BigInteger, V][] = [];
   [immerable] = true;
 
   constructor(items: [BigInteger, V][] = []) {
     items.forEach(([key, val]) => {
       this.set(key, val);
     });
-    this.generateCachedIter();
   }
 
   get size() {
-    return this.cachedIter?.length ?? Object.keys(this.root).length;
+    return Object.keys(this.root).length;
   }
 
 
@@ -31,14 +34,30 @@ export default class BigIntOrderedMap<V> implements Iterable<[BigInteger, V]> {
     return this.root[key.toString()] ?? null;
   }
 
+  gas(items: [BigInteger, V][]) {
+    return produce(this, draft => {
+      items.forEach(([key, value]) => {
+        draft.root[key.toString()] = castDraft(value);
+      });
+      draft.generateCachedIter();
+    }, 
+    (patches) => {
+      //console.log(`gassed with ${JSON.stringify(patches, null, 2)}`);
+    });
+  }
+
   set(key: BigInteger, value: V) {
-    this.root[key.toString()] = value;
+    return produce(this, draft => {
-    this.cachedIter = null;
+      draft.root[key.toString()] = castDraft(value);
+      draft.generateCachedIter();
+    });
   }
 
   clear() {
-    this.cachedIter = null;
+    return produce(this, draft => {
-    this.root = {}
+      draft.cachedIter = [];
+      draft.root = {}
+    });
   }
 
   has(key: BigInteger) {
@@ -46,17 +65,15 @@ export default class BigIntOrderedMap<V> implements Iterable<[BigInteger, V]> {
   }
 
   delete(key: BigInteger) {
-    const had = this.has(key);
+    return produce(this, draft => {
-    if(had) {
+      delete draft.root[key.toString()];
-      delete this.root[key.toString()];
+      draft.cachedIter  = draft.cachedIter.filter(([x]) => x.eq(key));
-      this.cachedIter = null;
+    });
-    }
-    return had;
   }
 
   [Symbol.iterator](): IterableIterator<[BigInteger, V]> {
     let idx = 0;
-    const result = this.generateCachedIter();
+    let result = [...this.cachedIter];
     return {
       [Symbol.iterator]: this[Symbol.iterator],
       next: (): IteratorResult<[BigInteger, V]> => {
@@ -79,19 +96,15 @@ export default class BigIntOrderedMap<V> implements Iterable<[BigInteger, V]> {
   }
 
   keys() {
-    return Object.keys(this.root).map(k => bigInt(k)).sort(sortBigInt)
+    return Array.from(this).map(([k,v]) => k);
   }
 
-  private generateCachedIter() {
+  generateCachedIter() {
-    if(this.cachedIter) {
-      return this.cachedIter;
-    }
     const result = Object.keys(this.root).map(key => {
       const num = bigInt(key);
       return [num, this.root[key]] as [BigInteger, V];
     }).sort(([a], [b]) => sortBigInt(a,b));
     this.cachedIter = result;
-    return result;
   }
 }