EntityStore: allow deleting entities

app/soapbox/entity-store/__tests__/reducer.test.ts

@@ -1,5 +1,6 @@
-import { entitiesFetchFail, entitiesFetchRequest, importEntities } from '../actions';
+import { deleteEntities, entitiesFetchFail, entitiesFetchRequest, importEntities } from '../actions';
-import reducer from '../reducer';
+import reducer, { State } from '../reducer';
+import { createListState } from '../utils';
 
 import type { EntityCache } from '../types';
 
@@ -76,4 +77,24 @@ test('failure adds the error to the state', () => {
   const result = reducer(undefined, action);
 
   expect(result.TestEntity!.lists.thingies!.state.error).toBe(error);
+});
+
+test('deleting items', () => {
+  const state: State = {
+    TestEntity: {
+      store: { '1': { id: '1' }, '2': { id: '2' }, '3': { id: '3' } },
+      lists: {
+        '': {
+          ids: new Set(['1', '2', '3']),
+          state: createListState(),
+        },
+      },
+    },
+  };
+
+  const action = deleteEntities(['3', '1'], 'TestEntity');
+  const result = reducer(state, action);
+
+  expect(result.TestEntity!.store).toMatchObject({ '2': { id: '2' } });
+  expect([...result.TestEntity!.lists['']!.ids]).toEqual(['2']);
 });

app/soapbox/entity-store/actions.ts

@@ -1,6 +1,7 @@
 import type { Entity, EntityListState } from './types';
 
 const ENTITIES_IMPORT = 'ENTITIES_IMPORT' as const;
+const ENTITIES_DELETE = 'ENTITIES_DELETE' as const;
 const ENTITIES_FETCH_REQUEST = 'ENTITIES_FETCH_REQUEST' as const;
 const ENTITIES_FETCH_SUCCESS = 'ENTITIES_FETCH_SUCCESS' as const;
 const ENTITIES_FETCH_FAIL = 'ENTITIES_FETCH_FAIL' as const;
@@ -15,6 +16,14 @@ function importEntities(entities: Entity[], entityType: string, listKey?: string
   };
 }
 
+function deleteEntities(ids: Iterable<string>, entityType: string) {
+  return {
+    type: ENTITIES_DELETE,
+    ids,
+    entityType,
+  };
+}
+
 function entitiesFetchRequest(entityType: string, listKey?: string) {
   return {
     type: ENTITIES_FETCH_REQUEST,
@@ -45,16 +54,19 @@ function entitiesFetchFail(entityType: string, listKey: string | undefined, erro
 /** Any action pertaining to entities. */
 type EntityAction =
   ReturnType<typeof importEntities>
+  | ReturnType<typeof deleteEntities>
   | ReturnType<typeof entitiesFetchRequest>
   | ReturnType<typeof entitiesFetchSuccess>
   | ReturnType<typeof entitiesFetchFail>;
 
 export {
   ENTITIES_IMPORT,
+  ENTITIES_DELETE,
   ENTITIES_FETCH_REQUEST,
   ENTITIES_FETCH_SUCCESS,
   ENTITIES_FETCH_FAIL,
   importEntities,
+  deleteEntities,
   entitiesFetchRequest,
   entitiesFetchSuccess,
   entitiesFetchFail,

app/soapbox/entity-store/reducer.ts

@@ -2,6 +2,7 @@ import produce, { enableMapSet } from 'immer';
 
 import {
   ENTITIES_IMPORT,
+  ENTITIES_DELETE,
   ENTITIES_FETCH_REQUEST,
   ENTITIES_FETCH_SUCCESS,
   ENTITIES_FETCH_FAIL,
@@ -43,6 +44,26 @@ const importEntities = (
   });
 };
 
+const deleteEntities = (
+  state: State,
+  entityType: string,
+  ids: Iterable<string>,
+) => {
+  return produce(state, draft => {
+    const cache = draft[entityType] ?? createCache();
+
+    for (const id of ids) {
+      delete cache.store[id];
+
+      for (const list of Object.values(cache.lists)) {
+        list?.ids.delete(id);
+      }
+    }
+
+    draft[entityType] = cache;
+  });
+};
+
 const setFetching = (
   state: State,
   entityType: string,
@@ -69,6 +90,8 @@ function reducer(state: Readonly<State> = {}, action: EntityAction): State {
   switch (action.type) {
     case ENTITIES_IMPORT:
       return importEntities(state, action.entityType, action.entities, action.listKey);
+    case ENTITIES_DELETE:
+      return deleteEntities(state, action.entityType, action.ids);
     case ENTITIES_FETCH_SUCCESS:
       return importEntities(state, action.entityType, action.entities, action.listKey, action.newState);
     case ENTITIES_FETCH_REQUEST:
@@ -80,4 +103,5 @@ function reducer(state: Readonly<State> = {}, action: EntityAction): State {
   }
 }
 
-export default reducer;
+export default reducer;
+export type { State };

app/soapbox/entity-store/utils.ts

@@ -1,4 +1,4 @@
-import type { Entity, EntityStore, EntityList, EntityCache } from './types';
+import type { Entity, EntityStore, EntityList, EntityCache, EntityListState } from './types';
 
 /** Insert the entities into the store. */
 const updateStore = (store: EntityStore, entities: Entity[]): EntityStore => {
@@ -26,13 +26,16 @@ const createCache = (): EntityCache => ({
 /** Create an empty entity list. */
 const createList = (): EntityList => ({
   ids: new Set(),
-  state: {
+  state: createListState(),
-    next: undefined,
+});
-    prev: undefined,
+
-    fetching: false,
+/** Create an empty entity list state. */
-    error: null,
+const createListState = (): EntityListState => ({
-    lastFetchedAt: undefined,
+  next: undefined,
-  },
+  prev: undefined,
+  fetching: false,
+  error: null,
+  lastFetchedAt: undefined,
 });
 
 export {
@@ -40,4 +43,5 @@ export {
   updateList,
   createCache,
   createList,
+  createListState,
 };

tsconfig.json

@@ -6,7 +6,7 @@
     "strict": true,
     "module": "es2022",
     "lib": ["es2019", "es6", "dom", "webworker"],
-    "target": "es5",
+    "target": "es2015",
     "jsx": "react",
     "allowJs": true,
     "moduleResolution": "node",