Prefer const enums due to typescript being stricter with them

.eslintrc.js

@@ -77,6 +77,15 @@ module.exports = {
                 additionalTestBlockFunctions: ["beforeAll", "beforeEach", "oldBackendOnly"],
             },
         ],
+
+        // Prefer const enums
+        "no-restricted-syntax": [
+            "error",
+            {
+                selector: "TSEnumDeclaration:not([const=true])",
+                message: "Don't declare non-const enums",
+            },
+        ],
     },
     overrides: [
         {

spec/test-utils/SyncResponder.ts

@@ -31,7 +31,7 @@ export interface ISyncResponder {
     sendOrQueueSyncResponse(response: object): void;
 }
 
-enum SyncResponderState {
+const enum SyncResponderState {
     IDLE,
     WAITING_FOR_REQUEST,
     WAITING_FOR_RESPONSE,

spec/unit/crypto/verification/sas.spec.ts

@@ -17,7 +17,7 @@ limitations under the License.
 import "../../../olm-loader";
 import { makeTestClients } from "./util";
 import { MatrixEvent } from "../../../../src/models/event";
-import { ISasEvent, SAS, SasEvent } from "../../../../src/crypto/verification/SAS";
+import { ISasEvent, SAS } from "../../../../src/crypto/verification/SAS";
 import { DeviceInfo, IDevice } from "../../../../src/crypto/deviceinfo";
 import { CryptoEvent, verificationMethods } from "../../../../src/crypto";
 import * as olmlib from "../../../../src/crypto/olmlib";
@@ -28,6 +28,7 @@ import { IVerificationChannel } from "../../../../src/crypto/verification/reques
 import { MatrixClient } from "../../../../src";
 import { VerificationRequest } from "../../../../src/crypto/verification/request/VerificationRequest";
 import { TestClient } from "../../../TestClient";
+import { VerifierEvent } from "../../../../src/crypto-api/verification";
 
 const Olm = global.Olm;
 
@@ -134,7 +135,7 @@ describe("SAS verification", function () {
 
             bobPromise = new Promise<VerificationBase<any, any>>((resolve, reject) => {
                 bob.client.on(CryptoEvent.VerificationRequest, (request) => {
-                    (<SAS>request.verifier!).on(SasEvent.ShowSas, (e) => {
+                    (<SAS>request.verifier!).on(VerifierEvent.ShowSas, (e) => {
                         if (!e.sas.emoji || !e.sas.decimal) {
                             e.cancel();
                         } else if (!aliceSasEvent) {
@@ -159,7 +160,7 @@ describe("SAS verification", function () {
                 bob.client.getUserId()!,
                 bob.deviceId!,
             ) as SAS;
-            aliceVerifier.on(SasEvent.ShowSas, (e) => {
+            aliceVerifier.on(VerifierEvent.ShowSas, (e) => {
                 if (!e.sas.emoji || !e.sas.decimal) {
                     e.cancel();
                 } else if (!bobSasEvent) {
@@ -418,7 +419,7 @@ describe("SAS verification", function () {
 
         const bobPromise = new Promise<VerificationBase<any, any>>((resolve, reject) => {
             bob.client.on(CryptoEvent.VerificationRequest, (request) => {
-                (<SAS>request.verifier!).on(SasEvent.ShowSas, (e) => {
+                (<SAS>request.verifier!).on(VerifierEvent.ShowSas, (e) => {
                     e.mismatch();
                 });
                 resolve(request.verifier!);
@@ -509,7 +510,7 @@ describe("SAS verification", function () {
             bobPromise = new Promise<void>((resolve, reject) => {
                 bob.client.on(CryptoEvent.VerificationRequest, async (request) => {
                     const verifier = request.beginKeyVerification(SAS.NAME) as SAS;
-                    verifier.on(SasEvent.ShowSas, (e) => {
+                    verifier.on(VerifierEvent.ShowSas, (e) => {
                         if (!e.sas.emoji || !e.sas.decimal) {
                             e.cancel();
                         } else if (!aliceSasEvent) {
@@ -533,7 +534,7 @@ describe("SAS verification", function () {
             const aliceRequest = await alice.client.requestVerificationDM(bob.client.getUserId()!, "!room_id");
             await aliceRequest.waitFor((r) => r.started);
             aliceVerifier = aliceRequest.verifier! as SAS;
-            aliceVerifier.on(SasEvent.ShowSas, (e) => {
+            aliceVerifier.on(VerifierEvent.ShowSas, (e) => {
                 if (!e.sas.emoji || !e.sas.decimal) {
                     e.cancel();
                 } else if (!bobSasEvent) {

spec/unit/queueToDevice.spec.ts

@@ -44,7 +44,7 @@ const FAKE_MSG = {
     payload: FAKE_PAYLOAD,
 };
 
-enum StoreType {
+const enum StoreType {
     Memory = "Memory",
     IndexedDB = "IndexedDB",
 }

src/@types/PushRules.ts

@@ -17,13 +17,13 @@ limitations under the License.
 // allow camelcase as these are things that go onto the wire
 /* eslint-disable camelcase */
 
-export enum PushRuleActionName {
+export const enum PushRuleActionName {
     DontNotify = "dont_notify",
     Notify = "notify",
     Coalesce = "coalesce",
 }
 
-export enum TweakName {
+export const enum TweakName {
     Highlight = "highlight",
     Sound = "sound",
 }
@@ -38,7 +38,7 @@ export type TweakSound = Tweak<TweakName.Sound, string>;
 
 export type Tweaks = TweakHighlight | TweakSound;
 
-export enum ConditionOperator {
+export const enum ConditionOperator {
     ExactEquals = "==",
     LessThan = "<",
     GreaterThan = ">",
@@ -60,7 +60,7 @@ export function isDmMemberCountCondition(condition: AnyMemberCountCondition): bo
     return condition === "==2" || condition === "2";
 }
 
-export enum ConditionKind {
+export const enum ConditionKind {
     EventMatch = "event_match",
     EventPropertyIs = "event_property_is",
     EventPropertyContains = "event_property_contains",
@@ -127,15 +127,15 @@ export type PushRuleCondition =
     | ICallStartedCondition
     | ICallStartedPrefixCondition;
 
-export enum PushRuleKind {
+export const enum PushRuleKind {
     Override = "override",
     ContentSpecific = "content",
     RoomSpecific = "room",
     SenderSpecific = "sender",
     Underride = "underride",
 }
 
-export enum RuleId {
+export const enum RuleId {
     Master = ".m.rule.master",
     IsUserMention = ".org.matrix.msc3952.is_user_mention",
     IsRoomMention = ".org.matrix.msc3952.is_room_mention",

src/@types/auth.ts

@@ -63,7 +63,7 @@ export interface ISSOFlow extends ILoginFlow {
     [DELEGATED_OIDC_COMPATIBILITY.altName]?: boolean;
 }
 
-export enum IdentityProviderBrand {
+export const enum IdentityProviderBrand {
     Gitlab = "gitlab",
     Github = "github",
     Apple = "apple",
@@ -92,7 +92,7 @@ export interface ILoginParams {
 }
 /* eslint-enable camelcase */
 
-export enum SSOAction {
+export const enum SSOAction {
     /** The user intends to login to an existing account */
     LOGIN = "login",
 

src/@types/event.ts

@@ -16,7 +16,7 @@ limitations under the License.
 
 import { UnstableValue } from "../NamespacedValue";
 
-export enum EventType {
+export const enum EventType {
     // Room state events
     RoomCanonicalAlias = "m.room.canonical_alias",
     RoomCreate = "m.room.create",
@@ -95,14 +95,14 @@ export enum EventType {
     GroupCallMemberPrefix = "org.matrix.msc3401.call.member",
 }
 
-export enum RelationType {
+export const enum RelationType {
     Annotation = "m.annotation",
     Replace = "m.replace",
     Reference = "m.reference",
     Thread = "m.thread",
 }
 
-export enum MsgType {
+export const enum MsgType {
     Text = "m.text",
     Emote = "m.emote",
     Notice = "m.notice",
@@ -116,7 +116,7 @@ export enum MsgType {
 
 export const RoomCreateTypeField = "type";
 
-export enum RoomType {
+export const enum RoomType {
     Space = "m.space",
     UnstableCall = "org.matrix.msc3417.call",
     ElementVideo = "io.element.video",

src/@types/location.ts

@@ -20,7 +20,7 @@ import { EitherAnd } from "matrix-events-sdk";
 import { UnstableValue } from "../NamespacedValue";
 import { M_TEXT } from "./extensible_events";
 
-export enum LocationAssetType {
+export const enum LocationAssetType {
     Self = "m.self",
     Pin = "m.pin",
 }

src/@types/partials.ts

@@ -28,12 +28,12 @@ export interface IImageInfo {
     h?: number;
 }
 
-export enum Visibility {
+export const enum Visibility {
     Public = "public",
     Private = "private",
 }
 
-export enum Preset {
+export const enum Preset {
     PrivateChat = "private_chat",
     TrustedPrivateChat = "trusted_private_chat",
     PublicChat = "public_chat",
@@ -44,7 +44,7 @@ export type ResizeMethod = "crop" | "scale";
 export type IdServerUnbindResult = "no-support" | "success";
 
 // Knock and private are reserved keywords which are not yet implemented.
-export enum JoinRule {
+export const enum JoinRule {
     Public = "public",
     Invite = "invite",
     /**
@@ -55,7 +55,7 @@ export enum JoinRule {
     Restricted = "restricted",
 }
 
-export enum RestrictedAllowType {
+export const enum RestrictedAllowType {
     RoomMembership = "m.room_membership",
 }
 
@@ -67,12 +67,12 @@ export interface IJoinRuleEventContent {
     }[];
 }
 
-export enum GuestAccess {
+export const enum GuestAccess {
     CanJoin = "can_join",
     Forbidden = "forbidden",
 }
 
-export enum HistoryVisibility {
+export const enum HistoryVisibility {
     Invited = "invited",
     Joined = "joined",
     Shared = "shared",

src/@types/read_receipts.ts

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-export enum ReceiptType {
+export const enum ReceiptType {
     Read = "m.read",
     FullyRead = "m.fully_read",
     ReadPrivate = "m.read.private",

src/@types/search.ts

@@ -48,7 +48,7 @@ export interface ISearchResult {
     context: IResultContext;
 }
 
-enum GroupKey {
+const enum GroupKey {
     RoomId = "room_id",
     Sender = "sender",
 }
@@ -76,7 +76,7 @@ interface IResultCategories {
 
 export type SearchKey = "content.body" | "content.name" | "content.topic";
 
-export enum SearchOrderBy {
+export const enum SearchOrderBy {
     Recent = "recent",
     Rank = "rank",
 }

src/@types/threepids.ts

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-export enum ThreepidMedium {
+export const enum ThreepidMedium {
     Email = "email",
     Phone = "msisdn",
 }

src/autodiscovery.ts

@@ -22,14 +22,16 @@ import { MatrixError, Method, timeoutSignal } from "./http-api";
 // Dev note: Auto discovery is part of the spec.
 // See: https://matrix.org/docs/spec/client_server/r0.4.0.html#server-discovery
 
-export enum AutoDiscoveryAction {
+export const enum AutoDiscoveryAction {
     SUCCESS = "SUCCESS",
     IGNORE = "IGNORE",
     PROMPT = "PROMPT",
     FAIL_PROMPT = "FAIL_PROMPT",
     FAIL_ERROR = "FAIL_ERROR",
 }
 
+// Allow this non-const enum
+// eslint-disable-next-line no-restricted-syntax
 enum AutoDiscoveryError {
     Invalid = "Invalid homeserver discovery response",
     GenericFailure = "Failed to get autodiscovery configuration from server",

src/client.ts

@@ -398,7 +398,7 @@ export interface IMatrixClientCreateOpts extends ICreateClientOpts {
     usingExternalCrypto?: boolean;
 }
 
-export enum PendingEventOrdering {
+export const enum PendingEventOrdering {
     Chronological = "chronological",
     Detached = "detached",
 }
@@ -478,7 +478,7 @@ export interface IStartClientOpts {
 
 export interface IStoredClientOpts extends IStartClientOpts {}
 
-export enum RoomVersionStability {
+export const enum RoomVersionStability {
     Stable = "stable",
     Unstable = "unstable",
 }
@@ -521,7 +521,7 @@ export interface ICrossSigningKey {
     user_id: string;
 }
 
-enum CrossSigningKeyType {
+const enum CrossSigningKeyType {
     MasterKey = "master_key",
     SelfSigningKey = "self_signing_key",
     UserSigningKey = "user_signing_key",
@@ -879,7 +879,7 @@ interface IWhoamiResponse {
 // Probably not the most graceful solution but does a good enough job for now
 const EVENT_ID_PREFIX = "$";
 
-export enum ClientEvent {
+export const enum ClientEvent {
     Sync = "sync",
     Event = "event",
     ToDeviceEvent = "toDeviceEvent",

src/crypto-api.ts

@@ -20,7 +20,7 @@ import { DeviceMap } from "./models/device";
 import { UIAuthCallback } from "./interactive-auth";
 
 /** Types of cross-signing key */
-export enum CrossSigningKey {
+export const enum CrossSigningKey {
     Master = "master",
     SelfSigning = "self_signing",
     UserSigning = "user_signing",

src/crypto-api/verification.ts

@@ -17,7 +17,7 @@ limitations under the License.
 import { MatrixEvent } from "../models/event";
 
 /** Events emitted by `Verifier`. */
-export enum VerifierEvent {
+export const enum VerifierEvent {
     /**
      * The verification has been cancelled, by us or the other side.
      *

src/crypto/CrossSigning.ts

@@ -582,7 +582,7 @@ function deviceToObject(device: DeviceInfo, userId: string): DeviceObject {
     };
 }
 
-export enum CrossSigningLevel {
+export const enum CrossSigningLevel {
     MASTER = 4,
     USER_SIGNING = 2,
     SELF_SIGNING = 1,

src/crypto/DeviceList.ts

@@ -51,7 +51,7 @@ import { CryptoEvent, CryptoEventHandlerMap } from "./index";
  */
 
 // constants for DeviceList.deviceTrackingStatus
-export enum TrackingStatus {
+export const enum TrackingStatus {
     NotTracked,
     PendingDownload,
     DownloadInProgress,

src/crypto/OutgoingRoomKeyRequestManager.ts

@@ -63,7 +63,7 @@ const SEND_KEY_REQUESTS_DELAY_MS = 500;
  * (deleted)  <---------------------------+
  * ```
  */
-export enum RoomKeyRequestState {
+export const enum RoomKeyRequestState {
     /** request not yet sent */
     Unsent,
     /** request sent, awaiting reply */