Enable typechecking for sidebar/store/modules

- Add JSDoc for the `actionTypes` function. This uses an advanced
  TS feature called "mapped types" [1] to specify that the result is an
  object with the same keys as the input object, but where the values
  are strings rather than functions.

  Going forwards there are likely better ways to replace `actionTypes`.
  The original purpose was to make sure that the `type` field of each action
  object matches up with a key of the `updates` object.

- Fix various existing JSDoc errors
- Add imports for the existing `Group` and `Annotation` references
- Add missing `group` property to `Annotation` type

[1] https://www.typescriptlang.org/docs/handbook/advanced-types.html#mapped-types
    (See in particular the `in keyof T` mentions).

src/sidebar/store/modules/annotations.js

@@ -3,6 +3,10 @@
  * sidebar.
  */
 
+/**
+ * @typedef {import('../../../types/api').Annotation} Annotation
+ */
+
 import { createSelector } from 'reselect';
 
 import * as metadata from '../../util/annotation-metadata';
@@ -56,7 +60,7 @@ function findByTag(annotations, tag) {
  * from the service.
  *
  * @param {Object} annotation
- * @param {Number} tag - The `$tag` value that should be used for this
+ * @param {string} tag - The `$tag` value that should be used for this
  *                       if it doesn't have a `$tag` already
  * @return {Object} - annotation with local (`$*`) fields set
  */
@@ -226,7 +230,7 @@ function updateFlagStatus(id, isFlagged) {
 /**
  * Add these `annotations` to the current collection of annotations in the store.
  *
- * @param {Object}[] annotations - Array of annotation objects to add.
+ * @param {Annotation[]} annotations - Array of annotation objects to add.
  */
 function addAnnotations(annotations) {
   return function (dispatch, getState) {
@@ -344,7 +348,7 @@ function unhideAnnotation(id) {
 /**
  * Return all loaded annotations which have been saved to the server.
  *
- * @param {state} - The global app state
+ * @param {Object} state - The global app state
  */
 function savedAnnotations(state) {
   return state.annotations.annotations.filter(function (ann) {
@@ -365,7 +369,7 @@ function annotationExists(state, id) {
  * If an annotation does not have an ID because it has not been created on
  * the server, there will be no entry for it in the returned array.
  *
- * @param {string[]} Local tags of annotations to look up
+ * @param {string[]} tags - Local tags of annotations to look up
  */
 function findIDsForTags(state, tags) {
   const ids = [];

src/sidebar/store/modules/groups.js

@@ -4,6 +4,10 @@ import * as util from '../util';
 
 import session from './session';
 
+/**
+ * @typedef {import('../../../types/api').Group} Group
+ */
+
 function init() {
   return {
     /**
@@ -97,7 +101,7 @@ function loadGroups(groups) {
 /**
  * Return the currently focused group.
  *
- * @return {Group|null}
+ * @return {Group|undefined|null}
  */
 function focusedGroup(state) {
   if (!state.groups.focusedGroupId) {

src/sidebar/store/modules/real-time-updates.js

@@ -3,6 +3,10 @@
  * WebSocket connection to h's real-time API.
  */
 
+/**
+ * @typedef {import('../../../types/api').Annotation} Annotation
+ */
+
 import { createSelector } from 'reselect';
 
 import { actionTypes } from '../util';

src/sidebar/store/modules/selection.js

@@ -313,7 +313,7 @@ function setForceVisible(id, visible) {
 /**
  * Sets which annotations are currently focused.
  *
- * @param {Array<string>} Tags of annotations to focus
+ * @param {string[]} tags - Tags of annotations to focus
  */
 function focusAnnotations(tags) {
   return {

src/sidebar/store/modules/viewer.js

@@ -41,7 +41,7 @@ function setShowHighlights(show) {
 }
 
 /**
- * @param {boolean} sidebarState - If the sidebar is open
+ * @param {boolean} opened - If the sidebar is open
  */
 function setSidebarOpened(opened) {
   return { type: actions.SET_SIDEBAR_OPENED, opened };

src/sidebar/store/util.js

 /**
  * Return an object where each key in `updateFns` is mapped to the key itself.
+ *
+ * @template {Object.<string,Function>} T
+ * @param {T} reducers - Object containing reducer functions
+ * @return {{ [index in keyof T]: string }}
  */
-export function actionTypes(updateFns) {
-  return Object.keys(updateFns).reduce(function (types, key) {
+export function actionTypes(reducers) {
+  return Object.keys(reducers).reduce(function (types, key) {
     types[key] = key;
     return types;
-  }, {});
+  }, /** @type {any} */ ({}));
 }
 
 /**

src/tsconfig.json

@@ -17,6 +17,7 @@
     "shared/*.js",
     "shared/components/*.js",
     "sidebar/*.js",
+    "sidebar/store/modules/*.js",
     "sidebar/services/*.js",
     "sidebar/util/*.js"
   ],

src/types/api.js

@@ -12,6 +12,7 @@
  * @prop {string} [id]
  * @prop {string[]} [references]
  * @prop {string} created
+ * @prop {string} group
  * @prop {string} updated
  * @prop {string[]} tags
  * @prop {string} text