types: Make object types with indexer properties exact, in our code.

If all has gone to plan, I've improved *all* relevant object types
in our own code this way (not including libdefs). I cast a wide net
for all indexer properties, with a global search for

  \]:

in *.js files outside the flow-typed directory. Some results weren't
indexer properties, but among the ones that were, I made the inexact
ones exact.

src/__tests__/lib/exampleData.js

@@ -674,7 +674,7 @@ export const action = deepFreeze({
 // annotate `action` itself, because we want to keep the information of
 // which one has which specific type.)
 /* eslint-disable-next-line no-unused-expressions */
-(action: { [string]: Action });
+(action: {| [string]: Action |});
 
 /* ========================================================================
  * Action fragments

src/api/initialDataTypes.js

@@ -38,9 +38,9 @@ export type InitialDataPresence = {|
   presences: {| [email: string]: UserPresence |},
 |};
 
-export type AvailableVideoChatProviders = {
+export type AvailableVideoChatProviders = {|
   [providerName: string]: {| name: string, id: number |},
-};
+|};
 
 export type InitialDataRealm = {|
   jitsi_server_url?: string,
@@ -171,7 +171,7 @@ export type InitialDataSubscription = {|
 export type InitialDataUpdateDisplaySettings = {|
   default_language: string,
   emojiset: string,
-  emojiset_choices: { [string]: string },
+  emojiset_choices: {| [string]: string |},
   high_contrast_mode: boolean,
   left_side_userlist: boolean,
   night_mode: boolean,

src/api/modelTypes.js

@@ -30,9 +30,9 @@ export type ImageEmojiType = $ReadOnly<{|
   source_url: string,
 |}>;
 
-export type RealmEmojiById = $ReadOnly<{
+export type RealmEmojiById = $ReadOnly<{|
   [id: string]: ImageEmojiType,
-}>;
+|}>;
 
 export type RealmFilter = [string, string, number];
 
@@ -462,7 +462,7 @@ export type Submessage = $ReadOnly<{|
  *    `EVENT_NEW_MESSAGE` Redux action for the event;
  *  * `messages: Message[]` in a `/messages` (our `getMessages`) response,
  *    and our resulting `MESSAGE_FETCH_COMPLETE` Redux action;
- *  * `messages: { [id]: Message }` in our global Redux state.
+ *  * `messages: {| [id]: Message |}` in our global Redux state.
  *
  * References include:
  *  * the two example events at https://zulip.com/api/get-events-from-queue

src/boot/store.js

@@ -106,7 +106,7 @@ function dropCache(state: GlobalState): $Shape<GlobalState> {
  * a version number to track which migrations are already reflected in it,
  * so that each only has to be run once.
  */
-const migrations: { [string]: (GlobalState) => GlobalState } = {
+const migrations: {| [string]: (GlobalState) => GlobalState |} = {
   // The type is a lie, in several ways:
   //  * The actual object contains only the properties we persist:
   //    those in `storeKeys` and `cacheKeys`, but not `discardKeys`.

src/directSelectors.js

@@ -63,7 +63,7 @@ export const getFetching = (state: GlobalState): FetchingState => state.fetching
 
 export const getFlags = (state: GlobalState): FlagsState => state.flags;
 
-export const getReadFlags = (state: GlobalState): { [messageId: number]: boolean } =>
+export const getReadFlags = (state: GlobalState): {| [messageId: number]: boolean |} =>
   state.flags.read;
 
 export const getAllNarrows = (state: GlobalState): NarrowsState => state.narrows;

src/emoji/codePointMap.js

@@ -1,7 +1,7 @@
 /* @flow strict-local */
 
 /** Maps certain emoji to substitutes, for us to show instead. */
-export const override: { [code: string]: string } = {
+export const override: {| [code: string]: string |} = {
   // :check_mark: -> :check: because the former is invisible on a light
   // background, i.e. when not in night mode.
   '2714': '2705',
@@ -19,7 +19,7 @@ export const override: { [code: string]: string } = {
  * Reaction.emoji_code here:
  *   https://github.com/zulip/zulip/blob/master/zerver/models.py
  */
-export const unicodeCodeByName: { [name: string]: string } = {
+export const unicodeCodeByName: {| [name: string]: string |} = {
   '+1': '1f44d',
   '-1': '1f44e',
   '0': '0030-20e3',

src/emoji/data.js

@@ -35,7 +35,7 @@ export const codeToEmojiMap = objectFromEntries<string, string>(
  */
 export const getFilteredEmojis = (
   query: string,
-  activeImageEmojiByName: $ReadOnly<{ [string]: ImageEmojiType }>,
+  activeImageEmojiByName: $ReadOnly<{| [string]: ImageEmojiType |}>,
 ): $ReadOnlyArray<{| emoji_type: EmojiType, name: string, code: string |}> => {
   // We start by making a map from matching emoji names to a number
   // representing how good a match it is: 0 for a prefix match, 1 for a

src/emoji/emojiSelectors.js

@@ -10,7 +10,7 @@ export const getAllImageEmojiById: Selector<RealmEmojiById> = createSelector(
   getIdentity,
   getRawRealmEmoji,
   (identity, realmEmoji) => {
-    const result: { [string]: ImageEmojiType } = {};
+    const result: {| [string]: ImageEmojiType |} = {};
     [realmEmoji, zulipExtraEmojiMap].forEach(emojis => {
       Object.keys(emojis).forEach(id => {
         result[id] = {
@@ -26,7 +26,7 @@ export const getAllImageEmojiById: Selector<RealmEmojiById> = createSelector(
 export const getActiveImageEmojiById: Selector<RealmEmojiById> = createSelector(
   getAllImageEmojiById,
   emojis => {
-    const result: { [string]: ImageEmojiType } = {};
+    const result: {| [string]: ImageEmojiType |} = {};
     Object.keys(emojis).forEach(id => {
       if (!emojis[id].deactivated) {
         result[id] = emojis[id];
@@ -36,12 +36,12 @@ export const getActiveImageEmojiById: Selector<RealmEmojiById> = createSelector(
   },
 );
 
-export const getAllImageEmojiByCode: Selector<{ [string]: ImageEmojiType }> = createSelector(
+export const getAllImageEmojiByCode: Selector<{| [string]: ImageEmojiType |}> = createSelector(
   getAllImageEmojiById,
   emojis => objectFromEntries(Object.keys(emojis).map(id => [emojis[id].code, emojis[id]])),
 );
 
-export const getActiveImageEmojiByName: Selector<{ [string]: ImageEmojiType }> = createSelector(
+export const getActiveImageEmojiByName: Selector<{| [string]: ImageEmojiType |}> = createSelector(
   getActiveImageEmojiById,
   emojis => objectFromEntries(Object.keys(emojis).map(id => [emojis[id].name, emojis[id]])),
 );

src/emoji/zulipExtraEmojiMap.js

@@ -6,7 +6,7 @@ import type { ImageEmojiType } from '../types';
  * so that both emoji type can be handled in similiar way
  * thus id has no meaning here
  */
-const zulipExtraEmojiMap: { [id: string]: ImageEmojiType } = {
+const zulipExtraEmojiMap: {| [id: string]: ImageEmojiType |} = {
   zulip: {
     deactivated: false,
     code: 'zulip',

src/jsBackport.js

@@ -18,8 +18,8 @@
  * implement and is all we happened to need.  Would be nice to extend to
  * iterables.
  */
-export function objectFromEntries<+K, +V>(entries: $ReadOnlyArray<[K, V]>): { [K]: V } {
-  const obj = ({}: { [K]: V });
+export function objectFromEntries<+K, +V>(entries: $ReadOnlyArray<[K, V]>): {| [K]: V |} {
+  const obj = ({}: {| [K]: V |});
   entries.forEach(entry => {
     // ESLint bug?  I don't understand how this rule even applies to this line.
     // eslint-disable-next-line prefer-destructuring

src/message/messageActionSheet.js

@@ -237,7 +237,7 @@ const allButtonsRaw = {
 
 type ButtonCode = $Keys<typeof allButtonsRaw>;
 
-const allButtons: { [ButtonCode]: ButtonDescription } = allButtonsRaw;
+const allButtons: {| [ButtonCode]: ButtonDescription |} = allButtonsRaw;
 
 type ConstructSheetParams<MsgType: Message | Outbox = Message | Outbox> = {|
   backgroundData: BackgroundData,

src/pm-conversations/pmConversationsSelectors.js

@@ -38,8 +38,8 @@ export const getRecentConversationsLegacy: Selector<PmConversationData[]> = crea
   (
     ownUserId,
     messages: Message[],
-    unreadPms: { [number]: number },
-    unreadHuddles: { [string]: number },
+    unreadPms: {| [number]: number |},
+    unreadHuddles: {| [string]: number |},
     allUsersById,
   ): PmConversationData[] => {
     const items = messages

src/redux-persist-migrate/index.js

@@ -16,7 +16,7 @@ const processKey = key => {
 /* eslint-disable no-use-before-define */
 
 export default function createMigration(
-  manifest: { [string]: (State) => State },
+  manifest: {| [string]: (State) => State |},
   versionSelector: string | (State => number | string | void),
   versionSetter?: (State, number) => State,
 ): StoreEnhancer<State, Action, Dispatch<Action>> {
@@ -46,7 +46,7 @@ export default function createMigration(
 }
 
 export function createMigrationImpl(
-  manifest: { [string]: (State) => State },
+  manifest: {| [string]: (State) => State |},
   versionSelector: State => number | string | void,
   versionSetter: (State, number) => State,
 ): StoreEnhancer<State, Action, Dispatch<Action>> {

src/reduxTypes.js

@@ -73,20 +73,18 @@ export type CaughtUp = {|
  *
  * See `CaughtUp` for details on what each value means.
  */
-export type CaughtUpState = {
-  // TODO(flow-v0.126): Should be exact. See note in src/utils/jsonable.js.
+export type CaughtUpState = {|
   [narrow: string]: CaughtUp,
-};
+|};
 
 /**
  * The user's draft message, if any, in each conversation.
  *
  * The keys correspond to the keys in `NarrowsState`.
  */
-export type DraftsState = {
-  // TODO(flow-v0.126): Should be exact. See note in src/utils/jsonable.js.
+export type DraftsState = {|
   [narrow: string]: string,
-};
+|};
 
 export type Fetching = {|
   older: boolean,
@@ -100,10 +98,9 @@ export type Fetching = {|
  *
  * See also: `CaughtUpState`, `NarrowsState`.
  */
-export type FetchingState = {
-  // TODO(flow-v0.126): Should be exact. See note in src/utils/jsonable.js.
+export type FetchingState = {|
   [narrow: string]: Fetching,
-};
+|};
 
 /**
  * The message flags corresponding to all the messages in `MessagesState`.
@@ -112,18 +109,18 @@ export type FetchingState = {
  * incomplete, always in exactly the same way that `MessagesState` is.
  */
 export type FlagsState = {|
-  read: { [messageId: number]: boolean },
-  starred: { [messageId: number]: boolean },
-  collapsed: { [messageId: number]: boolean },
-  mentioned: { [messageId: number]: boolean },
-  wildcard_mentioned: { [messageId: number]: boolean },
-  summarize_in_home: { [messageId: number]: boolean },
-  summarize_in_stream: { [messageId: number]: boolean },
-  force_expand: { [messageId: number]: boolean },
-  force_collapse: { [messageId: number]: boolean },
-  has_alert_word: { [messageId: number]: boolean },
-  historical: { [messageId: number]: boolean },
-  is_me_message: { [messageId: number]: boolean },
+  read: {| [messageId: number]: boolean |},
+  starred: {| [messageId: number]: boolean |},
+  collapsed: {| [messageId: number]: boolean |},
+  mentioned: {| [messageId: number]: boolean |},
+  wildcard_mentioned: {| [messageId: number]: boolean |},
+  summarize_in_home: {| [messageId: number]: boolean |},
+  summarize_in_stream: {| [messageId: number]: boolean |},
+  force_expand: {| [messageId: number]: boolean |},
+  force_collapse: {| [messageId: number]: boolean |},
+  has_alert_word: {| [messageId: number]: boolean |},
+  historical: {| [messageId: number]: boolean |},
+  is_me_message: {| [messageId: number]: boolean |},
 |};
 
 export type FlagName = $Keys<FlagsState>;
@@ -207,9 +204,9 @@ export type OutboxState = Outbox[];
  * @prop (email) - Indexes over all users for which the app has received a
  *   presence status.
  */
-export type PresenceState = {
+export type PresenceState = {|
   [email: string]: UserPresence,
-};
+|};
 
 /**
  * Configuration for a video chat provider, as specified by the server.
@@ -290,12 +287,12 @@ export type TopicsState = {|
   [number]: Topic[],
 |};
 
-export type TypingState = {
+export type TypingState = {|
   [normalizedRecipients: string]: {
     time: number,
     userIds: UserId[],
   },
-};
+|};
 
 export type UserGroupsState = UserGroup[];
 

src/streams/StreamList.js

@@ -21,7 +21,7 @@ type Props = $ReadOnly<{|
   showDescriptions: boolean,
   showSwitch: boolean,
   streams: $ReadOnlyArray<PseudoSubscription>,
-  unreadByStream: $ReadOnly<{ [number]: number }>,
+  unreadByStream: $ReadOnly<{| [number]: number |}>,
   onPress: (streamName: string) => void,
   onSwitch?: (streamName: string, newValue: boolean) => void,
 |}>;

src/streams/SubscriptionsCard.js

@@ -24,7 +24,7 @@ const styles = createStyleSheet({
 
 type SelectorProps = $ReadOnly<{|
   subscriptions: Subscription[],
-  unreadByStream: $ReadOnly<{ [number]: number }>,
+  unreadByStream: $ReadOnly<{| [number]: number |}>,
 |}>;
 
 type Props = $ReadOnly<{|

src/styles/theme.js

@@ -11,7 +11,7 @@ export type ThemeData = {|
   dividerColor: string,
 |};
 
-export const themeData: { [name: ThemeName | 'light']: ThemeData } = {
+export const themeData: {| [name: ThemeName | 'light']: ThemeData |} = {
   night: {
     color: 'hsl(210, 11%, 85%)',
     backgroundColor: 'hsl(212, 28%, 18%)',

src/types.js

@@ -236,7 +236,7 @@ export type MessageLike =
   | $ReadOnly<Message>
   | $ReadOnly<{
       // $Shape<T> is unsound, per Flow docs, but $ReadOnly<$Shape<T>> is not
-      ...$Shape<{ [$Keys<Message>]: void }>,
+      ...$Shape<{| [$Keys<Message>]: void |}>,
       sender_id?: UserId, // TODO: Drop this once required in Outbox.
       ...Outbox,
     }>;
@@ -246,7 +246,7 @@ type IntlMessageFormatValue = string | number | boolean | null | void;
 
 export type LocalizableText =
   | string
-  | { text: string, values?: { [string]: IntlMessageFormatValue } };
+  | { text: string, values?: {| [string]: IntlMessageFormatValue |} };
 
 /**
  * Usually called `_`, and invoked like `_('Message')` -> `'Nachricht'`.
@@ -264,7 +264,7 @@ export type LocalizableText =
  * @prop intl - The full react-intl API, for more complex situations.
  */
 export type GetText = {
-  (message: string, values?: { [string]: IntlMessageFormatValue }): string,
+  (message: string, values?: {| [string]: IntlMessageFormatValue |}): string,
   intl: IntlShape,
 };
 

src/unread/unreadSelectors.js

@@ -13,12 +13,12 @@ import { pmUnreadsKeyFromPmKeyIds } from '../utils/recipient';
 import { getUnreadStreams, getUnreadPms, getUnreadHuddles, getUnreadMentions } from './unreadModel';
 
 /** The number of unreads in each stream, excluding muted topics, by stream ID. */
-export const getUnreadByStream: Selector<{ [number]: number }> = createSelector(
+export const getUnreadByStream: Selector<{| [number]: number |}> = createSelector(
   getUnreadStreams,
   getSubscriptionsById,
   getMute,
   (unreadStreams, subscriptionsById, mute) => {
-    const totals = ({}: { [number]: number });
+    const totals = ({}: {| [number]: number |});
     unreadStreams.forEach(stream => {
       if (!totals[stream.stream_id]) {
         totals[stream.stream_id] = 0;
@@ -50,10 +50,10 @@ export const getUnreadStreamTotal: Selector<number> = createSelector(
  *
  * See also `getUnreadByHuddles`, for group PM threads.
  */
-export const getUnreadByPms: Selector<{ [number]: number }> = createSelector(
+export const getUnreadByPms: Selector<{| [number]: number |}> = createSelector(
   getUnreadPms,
   unreadPms => {
-    const totals = ({}: { [number]: number });
+    const totals = ({}: {| [number]: number |});
     unreadPms.forEach(pm => {
       totals[pm.sender_id] = totals[pm.sender_id] || 0 + pm.unread_message_ids.length;
     });
@@ -80,10 +80,10 @@ export const getUnreadPmsTotal: Selector<number> = createSelector(
  *
  * See also `getUnreadByPms`, for 1:1 PM threads.
  */
-export const getUnreadByHuddles: Selector<{ [string]: number }> = createSelector(
+export const getUnreadByHuddles: Selector<{| [string]: number |}> = createSelector(
   getUnreadHuddles,
   unreadHuddles => {
-    const totals = ({}: { [string]: number });
+    const totals = ({}: {| [string]: number |});
     unreadHuddles.forEach(huddle => {
       totals[huddle.user_ids_string] =
         totals[huddle.user_ids_string] || 0 + huddle.unread_message_ids.length;