integrating immer

package-lock.json

@@ -3263,6 +3263,11 @@
       "integrity": "sha1-xg7taebY/bazEEofy8ocGS3FtQE=",
       "dev": true
     },
+    "immer": {
+      "version": "1.12.1",
+      "resolved": "https://registry.npmjs.org/immer/-/immer-1.12.1.tgz",
+      "integrity": "sha512-3fmKM6ovaqDt0CdC9daXpNi5x/YCYS3i4cwLdTVkhJdk5jrDXoPs7lCm3IqM3yhfSnz4tjjxbRG2CziQ7m8ztg=="
+    },
     "import-local": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/import-local/-/import-local-2.0.0.tgz",

package.json

@@ -4,7 +4,7 @@
   "description": "",
   "main": "index.js",
   "scripts": {
-    "start": "webpack-dev-server --mode development",
+    "start": "webpack-dev-server --mode development --progress",
     "build": "webpack --mode production"
   },
   "keywords": [],
@@ -28,6 +28,7 @@
     "react": "^16.7.0",
     "react-dom": "^16.7.0",
     "redux": "^4.0.1",
-    "react-redux": "^6.0.0"
+    "react-redux": "^6.0.0",
+    "immer": "^1.12.1"
   }
 }

playground/src/components/TodoApp.tsx

@@ -8,18 +8,21 @@ import { TodoItem, FilterTypes } from '../store';
 export interface TodoAppProps {
   todos: { [id: string]: TodoItem };
   filter: FilterTypes;
+  add: (label: string) => void;
+  remove: (id: string) => void;
+  setFilter: (filter: FilterTypes) => void;
 }
 
 export class TodoApp extends React.Component<TodoAppProps> {
   render() {
-    const { todos, filter } = this.props;
+    const { todos, filter, add, remove, setFilter } = this.props;
 
     return (
       <Stack horizontalAlign="center">
         <Stack style={{ width: 650 }} verticalGap={25}>
-          <TodoHeader />
+          <TodoHeader {...{ add, remove, filter }} />
           <TodoList {...{ todos, filter }} />
-          <TodoFooter />
+          <TodoFooter {...{ todos, setFilter }} />
         </Stack>
       </Stack>
     );

playground/src/components/TodoAppContainer.tsx

@@ -1,5 +1,5 @@
 import * as actions from '../actions';
-import { Store } from '../store';
+import { Store, FilterTypes } from '../store';
 import { connect } from 'react-redux';
 import { Dispatch } from 'redux';
 import { TodoApp } from './TodoApp';
@@ -14,7 +14,11 @@ export function mapStateToProps({ todos, filter }: Store) {
 export function mapDispatchToProps(dispatch: Dispatch<actions.TodoAction>) {
   return {
     add: (label: string) => dispatch(actions.add(label)),
-    remove: (id: string) => dispatch(actions.remove(id))
+    remove: (id: string) => dispatch(actions.remove(id)),
+    complete: (id: string) => dispatch(actions.complete(id)),
+    completeAll: () => dispatch(actions.completeAll()),
+    clear: () => dispatch(actions.clear()),
+    setFilter: (filter: FilterTypes) => dispatch(actions.filter(filter))
   };
 }
 

playground/src/components/TodoHeader.tsx

@@ -1,23 +1,54 @@
 import React from 'react';
 import { Text, Stack } from '@uifabric/experiments';
-import { Checkbox, Button, Pivot, PivotItem, TextField } from 'office-ui-fabric-react';
+import { Pivot, PivotItem, TextField } from 'office-ui-fabric-react';
+import { add } from '../actions';
 
-export interface TodoFooterProps {}
+export interface TodoHeaderProps {
+  add: (label: string) => void;
+  remove: (id: string) => void;
+}
 
-export const TodoHeader = (props: TodoFooterProps) => {
+export interface TodoHeaderState {
-  return (
+  labelInput: string;
-    <Stack>
+}
-      <Stack horizontal horizontalAlign="center">
+
-        <Text variant="xxLarge">todos</Text>
+export class TodoHeader extends React.Component<TodoHeaderProps, TodoHeaderState> {
+  constructor(props: TodoHeaderProps) {
+    super(props);
+    this.state = { labelInput: undefined };
+  }
+
+  onKeyPress = (evt: React.KeyboardEvent) => {
+    if (evt.charCode === 13) {
+      this.props.add(this.state.labelInput);
+      this.setState({ labelInput: undefined });
+    }
+  };
+
+  onChange = (evt: React.FormEvent<HTMLInputElement>, newValue: string) => {
+    this.setState({ labelInput: newValue });
+  };
+
+  render() {
+    return (
+      <Stack>
+        <Stack horizontal horizontalAlign="center">
+          <Text variant="xxLarge">todos</Text>
+        </Stack>
+
+        <TextField
+          placeholder="What needs to be done?"
+          value={this.state.labelInput}
+          onChange={this.onChange}
+          onKeyPress={this.onKeyPress}
+        />
+
+        <Pivot>
+          <PivotItem headerText="all" />
+          <PivotItem headerText="active" />
+          <PivotItem headerText="completed" />
+        </Pivot>
       </Stack>
-
+    );
-      <TextField placeholder="What needs to be done?" />
+  }
-
+}
-      <Pivot>
-        <PivotItem headerText="all" />
-        <PivotItem headerText="active" />
-        <PivotItem headerText="completed" />
-      </Pivot>
-    </Stack>
-  );
-};

playground/src/reducers/createReducer.ts

@@ -1,13 +1,14 @@
 import { Reducer } from 'redux';
 import { ActionTypes, TodoAction } from '../actions';
+import { Draft, produce } from 'immer';
 
 export function createReducer<T>(
   initialState: T,
-  handlers: { [actionType in ActionTypes]?: (state: T, action: TodoAction) => T }
+  handlers: { [actionType in ActionTypes]?: (state: Draft<T>, action: TodoAction) => T }
 ): Reducer<T> {
   return function reducer(state = initialState, action: TodoAction): T {
     if (handlers.hasOwnProperty(action.type)) {
-      return handlers[action.type](state, action);
+      return produce(state, draft => handlers[action.type](draft, action));
     } else {
       return state;
     }

playground/src/reducers/index.ts

@@ -5,17 +5,23 @@ import { combineReducers } from 'redux';
 let counter = 0;
 
 export const reducer = combineReducers<Store>({
-  todos: createReducer(
+  todos: createReducer<Store['todos']>(
     {},
     {
-      add(state, action) {
+      add(draft, action) {
         const id = String(counter++);
-        return { ...state, [id]: { label: action.label, completed: false } };
+        draft[id] = { label: action.label, completed: false };
+        return draft;
+      },
+
+      remove(draft, action) {
+        delete draft[action.id];
+        return draft;
       }
     }
   ),
   filter: createReducer<FilterTypes>('all', {
-    filter(state, action) {
+    filter(draft, action) {
       return action.filter;
     }
   })