step 9 exercise complete!

step2-09/demo/src/reducers/index.ts

@@ -0,0 +1,35 @@
+import { Store } from '../store';
+import { addTodo, remove, complete, clear, setFilter } from './pureFunctions';
+import { combineReducers } from 'redux';
+
+function todoReducer(state: Store['todos'] = {}, action: any): Store['todos'] {
+  switch (action.type) {
+    case 'addTodo':
+      return addTodo(state, action.id, action.label);
+
+    case 'remove':
+      return remove(state, action.id);
+
+    case 'clear':
+      return clear(state);
+
+    case 'complete':
+      return complete(state, action.id);
+  }
+
+  return state;
+}
+
+function filterReducer(state: Store['filter'] = 'all', action: any): Store['filter'] {
+  switch (action.type) {
+    case 'setFilter':
+      return setFilter(state, action.filter);
+  }
+
+  return state;
+}
+
+export const reducer = combineReducers({
+  todos: todoReducer,
+  filter: filterReducer
+});