refactor: ban TypeScript enums across internal-snaps

eslint.config.mjs

@@ -161,6 +161,11 @@ const config = createConfig([
           typescript,
         ]),
         ...NO_CONTROLLER_STATE_CHANGE_SELECTOR_OBJECTS,
+        {
+          selector: 'TSEnumDeclaration',
+          message:
+            "Don't use enums. There are a number of reasons why they are problematic, but the most important is that TypeScript treats them nominally, not structurally, and this can cause unexpected breaking changes. Instead, use an object + type, an array + type, or just a type. Learn more here: https://github.com/MetaMask/eslint-config/issues/417",
+        },
       ],
     },
   },

packages/bitcoin-wallet-snap/CHANGELOG.md

@@ -7,6 +7,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+**BREAKING:** Convert `CronjobMethod`, `Slip44`, `Purpose`, `Sep43ErrorCode`, `Fiat`, `CurrencyUnit`, `AccountFeature`, `AddressType`, `BalanceChangeType`, `ConfirmationStatus`, and `TransactionType` from TypeScript enums to `as const` objects with derived union types ([#XXX](https://github.com/MetaMask/internal-snaps/pull/XXX))
+- Member access (`Enum.Member`) and runtime values are unchanged
+- Type signatures change: `Enum` is now a union of string/number literals instead of a nominal enum type
+- `typeof Enum.Member` expressions in type positions now refer to literal values instead of enum member types
+
+
 ### Fixed
 
 - Ensure certain errors are stringified correctly ([#179](https://github.com/MetaMask/internal-snaps/pull/179))

packages/bitcoin-wallet-snap/src/entities/account.ts

@@ -222,17 +222,20 @@ export type BitcoinAccount = {
   applyUnconfirmedTx(tx: Transaction, lastSeen: number): void;
 };
 
-export enum AccountCapability {
-  SignPsbt = 'signPsbt',
-  ComputeFee = 'computeFee',
-  FillPsbt = 'fillPsbt',
-  BroadcastPsbt = 'broadcastPsbt',
-  SendTransfer = 'sendTransfer',
-  GetUtxo = 'getUtxo',
-  ListUtxos = 'listUtxos',
-  PublicDescriptor = 'publicDescriptor',
-  SignMessage = 'signMessage',
-}
+export const AccountCapability = {
+  SignPsbt: 'signPsbt',
+  ComputeFee: 'computeFee',
+  FillPsbt: 'fillPsbt',
+  BroadcastPsbt: 'broadcastPsbt',
+  SendTransfer: 'sendTransfer',
+  GetUtxo: 'getUtxo',
+  ListUtxos: 'listUtxos',
+  PublicDescriptor: 'publicDescriptor',
+  SignMessage: 'signMessage',
+} as const;
+
+export type AccountCapability =
+  (typeof AccountCapability)[keyof typeof AccountCapability];
 
 /**
  * BitcoinAccountRepository is a repository that manages Bitcoin accounts.
@@ -332,18 +335,22 @@ export type BitcoinAccountRepository = {
   getFrozenUTXOs(id: string): Promise<string[]>;
 };
 
-export enum Purpose {
-  Legacy = 44,
-  Segwit = 49,
-  NativeSegwit = 84,
-  Taproot = 86,
-  Multisig = 45,
-}
+export const Purpose = {
+  Legacy: 44,
+  Segwit: 49,
+  NativeSegwit: 84,
+  Taproot: 86,
+  Multisig: 45,
+} as const;
 
-export enum Slip44 {
-  Bitcoin = 0,
-  Testnet = 1,
-}
+export type Purpose = (typeof Purpose)[keyof typeof Purpose];
+
+export const Slip44 = {
+  Bitcoin: 0,
+  Testnet: 1,
+} as const;
+
+export type Slip44 = (typeof Slip44)[keyof typeof Slip44];
 
 export const addressTypeToPurpose: Record<AddressType, Purpose> = {
   p2pkh: Purpose.Legacy,

packages/bitcoin-wallet-snap/src/entities/confirmation.ts

@@ -39,10 +39,13 @@ export type SignPsbtConfirmationContext = {
   inputCount: number;
 };
 
-export enum ConfirmationEvent {
-  Confirm = 'confirmation-confirm',
-  Cancel = 'confirmation-cancel',
-}
+export const ConfirmationEvent = {
+  Confirm: 'confirmation-confirm',
+  Cancel: 'confirmation-cancel',
+} as const;
+
+export type ConfirmationEvent =
+  (typeof ConfirmationEvent)[keyof typeof ConfirmationEvent];
 
 /**
  * ConfirmationRepository is a repository that manages request confirmations for dApps.

packages/bitcoin-wallet-snap/src/entities/currency.ts

@@ -1,12 +1,14 @@
 import type { Network } from '@metamask/bitcoindevkit';
 
-export enum CurrencyUnit {
-  Bitcoin = 'BTC',
-  Testnet = 'tBTC',
-  Signet = 'sBTC',
-  Regtest = 'rBTC',
-  Fiat = 'fiat', // Can also be cryptos like ETH, but will be fiat for 99% of users
-}
+export const CurrencyUnit = {
+  Bitcoin: 'BTC',
+  Testnet: 'tBTC',
+  Signet: 'sBTC',
+  Regtest: 'rBTC',
+  Fiat: 'fiat', // Can also be cryptos like ETH, but will be fiat for 99% of users
+} as const;
+
+export type CurrencyUnit = (typeof CurrencyUnit)[keyof typeof CurrencyUnit];
 
 export type CurrencyRate = {
   conversionRate: number;

packages/bitcoin-wallet-snap/src/entities/send-flow.ts

@@ -43,18 +43,20 @@ export type SendFormContext = {
   locale: string;
 };
 
-export enum SendFormEvent {
-  Amount = 'amount',
-  Recipient = 'recipient',
-  ClearRecipient = 'clearRecipient',
-  ClearAmount = 'clearAmount',
-  Confirm = 'confirm',
-  Cancel = 'cancel',
-  Max = 'max',
-  Account = 'account',
-  Asset = 'asset',
-  SwitchCurrency = 'switchCurrency',
-}
+export const SendFormEvent = {
+  Amount: 'amount',
+  Recipient: 'recipient',
+  ClearRecipient: 'clearRecipient',
+  ClearAmount: 'clearAmount',
+  Confirm: 'confirm',
+  Cancel: 'cancel',
+  Max: 'max',
+  Account: 'account',
+  Asset: 'asset',
+  SwitchCurrency: 'switchCurrency',
+} as const;
+
+export type SendFormEvent = (typeof SendFormEvent)[keyof typeof SendFormEvent];
 
 export type ReviewTransactionContext = {
   from: string;
@@ -75,10 +77,13 @@ export type ReviewTransactionContext = {
   sendForm?: SendFormContext;
 };
 
-export enum ReviewTransactionEvent {
-  Send = 'send',
-  HeaderBack = 'headerBack',
-}
+export const ReviewTransactionEvent = {
+  Send: 'send',
+  HeaderBack: 'headerBack',
+} as const;
+
+export type ReviewTransactionEvent =
+  (typeof ReviewTransactionEvent)[keyof typeof ReviewTransactionEvent];
 
 /**
  * SendFlowRepository is a repository that manages Bitcoin Send flow interfaces.

packages/bitcoin-wallet-snap/src/entities/snap.ts

@@ -46,12 +46,15 @@ export type SyncResult = {
   transactionsToNotify: WalletTx[];
 };
 
-export enum TrackingSnapEvent {
-  TransactionFinalized = 'Transaction Finalized',
-  TransactionReceived = 'Transaction Received',
-  TransactionReorged = 'Transaction Reorged',
-  TransactionSubmitted = 'Transaction Submitted',
-}
+export const TrackingSnapEvent = {
+  TransactionFinalized: 'Transaction Finalized',
+  TransactionReceived: 'Transaction Received',
+  TransactionReorged: 'Transaction Reorged',
+  TransactionSubmitted: 'Transaction Submitted',
+} as const;
+
+export type TrackingSnapEvent =
+  (typeof TrackingSnapEvent)[keyof typeof TrackingSnapEvent];
 
 /**
  * The SnapClient represents the MetaMask Snap state and manages the BIP-32 entropy from the Wallet SRP.

packages/bitcoin-wallet-snap/src/handlers/CronHandler.ts

@@ -6,12 +6,14 @@ import { InexistentMethodError, SynchronizationError } from '../entities';
 import type { SnapClient, SyncResult } from '../entities';
 import type { SendFlowUseCases, AccountUseCases } from '../use-cases';
 
-export enum CronMethod {
-  SynchronizeAccounts = 'synchronizeAccounts',
-  RefreshRates = 'refreshRates',
-  SyncSelectedAccounts = 'syncSelectedAccounts',
-  FullScanAccount = 'fullScanAccount',
-}
+export const CronMethod = {
+  SynchronizeAccounts: 'synchronizeAccounts',
+  RefreshRates: 'refreshRates',
+  SyncSelectedAccounts: 'syncSelectedAccounts',
+  FullScanAccount: 'fullScanAccount',
+} as const;
+
+export type CronMethod = (typeof CronMethod)[keyof typeof CronMethod];
 
 export const SendFormRefreshRatesRequest = object({
   interfaceId: string(),

packages/bitcoin-wallet-snap/src/handlers/caip.ts

@@ -30,13 +30,15 @@ export const networkToScope = reverseMapping(scopeToNetwork);
 
 export const addressTypeToCaip = reverseMapping(caipToAddressType);
 
-export enum Caip19Asset {
-  Bitcoin = 'bip122:000000000019d6689c085ae165831e93/slip44:0',
-  Testnet = 'bip122:000000000933ea01ad0ee984209779ba/slip44:0',
-  Testnet4 = 'bip122:00000000da84f2bafbbc53dee25a72ae/slip44:0',
-  Signet = 'bip122:00000008819873e925422c1ff0f99f7c/slip44:0',
-  Regtest = 'bip122:regtest/slip44:0',
-}
+export const Caip19Asset = {
+  Bitcoin: 'bip122:000000000019d6689c085ae165831e93/slip44:0',
+  Testnet: 'bip122:000000000933ea01ad0ee984209779ba/slip44:0',
+  Testnet4: 'bip122:00000000da84f2bafbbc53dee25a72ae/slip44:0',
+  Signet: 'bip122:00000008819873e925422c1ff0f99f7c/slip44:0',
+  Regtest: 'bip122:regtest/slip44:0',
+} as const;
+
+export type Caip19Asset = (typeof Caip19Asset)[keyof typeof Caip19Asset];
 
 export const NetworkStruct = enums(Object.values(BtcScope));
 

packages/bitcoin-wallet-snap/src/handlers/validation.ts

@@ -22,25 +22,29 @@ import {
 import type { BitcoinAccount, CodifiedError, Logger } from '../entities';
 import { ValidationError } from '../entities';
 
-export enum RpcMethod {
-  StartSendTransactionFlow = 'startSendTransactionFlow',
-  SignAndSendTransaction = 'signAndSendTransaction',
-  ComputeFee = 'computeFee',
-  VerifyMessage = 'verifyMessage',
-  OnAddressInput = 'onAddressInput',
-  OnAmountInput = 'onAmountInput',
-  ConfirmSend = 'confirmSend',
-  SignRewardsMessage = 'signRewardsMessage',
-  SignProofOfOwnership = 'signProofOfOwnership',
-}
-
-export enum SendErrorCodes {
-  // eslint-disable-next-line @typescript-eslint/no-shadow
-  Required = 'Required',
-  Invalid = 'Invalid',
-  InsufficientBalance = 'InsufficientBalance',
-  InsufficientBalanceToCoverFee = 'InsufficientBalanceToCoverFee',
-}
+export const RpcMethod = {
+  StartSendTransactionFlow: 'startSendTransactionFlow',
+  SignAndSendTransaction: 'signAndSendTransaction',
+  ComputeFee: 'computeFee',
+  VerifyMessage: 'verifyMessage',
+  OnAddressInput: 'onAddressInput',
+  OnAmountInput: 'onAmountInput',
+  ConfirmSend: 'confirmSend',
+  SignRewardsMessage: 'signRewardsMessage',
+  SignProofOfOwnership: 'signProofOfOwnership',
+} as const;
+
+export type RpcMethod = (typeof RpcMethod)[keyof typeof RpcMethod];
+
+export const SendErrorCodes = {
+  Required: 'Required',
+  Invalid: 'Invalid',
+  InsufficientBalance: 'InsufficientBalance',
+  InsufficientBalanceToCoverFee: 'InsufficientBalanceToCoverFee',
+} as const;
+
+export type SendErrorCodes =
+  (typeof SendErrorCodes)[keyof typeof SendErrorCodes];
 
 export const NonEmptyStringStruct = refine(
   nonempty(string()),

packages/solana-wallet-snap/CHANGELOG.md

@@ -7,6 +7,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+**BREAKING:** Convert `SolMethod`, `AccountCreationType`, `TokenFeature`, `TokenStandard`, `TransactionScanType`, `TransactionStatus`, `TransactionType`, `AccountType`, `AccountScope`, `AccountFeature`, `Scope`, `CronjobMethod`, `ScheduleBackgroundEventMethod`, `Network`, `Sep43ErrorCode`, and `Secp256Instruction` from TypeScript enums to `as const` objects with derived union types ([#XXX](https://github.com/MetaMask/internal-snaps/pull/XXX))
+- Member access (`Enum.Member`) and runtime values are unchanged
+- Type signatures change: `Enum` is now a union of string/number literals instead of a nominal enum type
+
+
 ### Changed
 
 - Extract Snap-owned assets domain logic into `SnapAssetsAdapter`; `AssetsService` is a thin facade that delegates metadata, market data, fetch, persist, and account asset reads through the adapter (no Core routing yet). ([#121](https://github.com/MetaMask/internal-snaps/pull/121))

packages/solana-wallet-snap/src/core/clients/token-api-client/TokenApiClient.ts

@@ -89,7 +89,9 @@ export class TokenApiClient {
       // The Token API only supports the networks in TokenApiClient.supportedNetworks
       const supportedAssetTypes = assetTypes.filter((assetType) => {
         const { chainId } = parseCaipAssetType(assetType);
-        return TokenApiClient.supportedNetworks.includes(chainId as Network);
+        return TokenApiClient.supportedNetworks.includes(
+          chainId as (typeof TokenApiClient.supportedNetworks)[number],
+        );
       });
 
       if (supportedAssetTypes.length !== assetTypes.length) {

packages/solana-wallet-snap/src/core/constants/solana.ts

@@ -14,26 +14,30 @@ export const METAMASK_ORIGIN_URL = 'https://metamask.io';
  *
  * @see https://namespaces.chainagnostic.org/solana/caip2
  */
-export enum Network {
-  Mainnet = 'solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp',
-  Devnet = 'solana:EtWTRABZaYq6iMfeYKouRu166VU2xqa1',
-  Testnet = 'solana:4uhcVJyU9pJkvQyS88uRDiswHXSCkY3z',
-  Localnet = 'solana:123456789abcdef',
-}
-
-export enum KnownCaip19Id {
-  SolMainnet = `${Network.Mainnet}/slip44:501`,
-  SolDevnet = `${Network.Devnet}/slip44:501`,
-  SolTestnet = `${Network.Testnet}/slip44:501`,
-  SolLocalnet = `${Network.Localnet}/slip44:501`,
-  UsdcMainnet = `${Network.Mainnet}/token:EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v`,
-  UsdcDevnet = `${Network.Devnet}/token:4zMMC9srt5Ri5X14GAgXhaHii3GnPAEERYPJgZJDncDU`,
-  UsdcLocalnet = `${Network.Localnet}/token:EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v`,
-  EurcMainnet = `${Network.Mainnet}/token:HzwqbKZw8HxMN6bF2yFZNrht3c2iXXzpKcFu7uBEDKtr`,
-  EurcDevnet = `${Network.Devnet}/token:HzwqbKZw8HxMN6bF2yFZNrht3c2iXXzpKcFu7uBEDKtr`,
-  EurcLocalnet = `${Network.Localnet}/token:HzwqbKZw8HxMN6bF2yFZNrht3c2iXXzpKcFu7uBEDKtr`,
-  Ai16zMainnet = `${Network.Mainnet}/token:HeLp6NuQkmYB4pYWo2zYs22mESHXPQYzXbB8n4V98jwC`,
-}
+export const Network = {
+  Mainnet: 'solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp',
+  Devnet: 'solana:EtWTRABZaYq6iMfeYKouRu166VU2xqa1',
+  Testnet: 'solana:4uhcVJyU9pJkvQyS88uRDiswHXSCkY3z',
+  Localnet: 'solana:123456789abcdef',
+} as const;
+
+export type Network = (typeof Network)[keyof typeof Network];
+
+export const KnownCaip19Id = {
+  SolMainnet: `${Network.Mainnet}/slip44:501`,
+  SolDevnet: `${Network.Devnet}/slip44:501`,
+  SolTestnet: `${Network.Testnet}/slip44:501`,
+  SolLocalnet: `${Network.Localnet}/slip44:501`,
+  UsdcMainnet: `${Network.Mainnet}/token:EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v`,
+  UsdcDevnet: `${Network.Devnet}/token:4zMMC9srt5Ri5X14GAgXhaHii3GnPAEERYPJgZJDncDU`,
+  UsdcLocalnet: `${Network.Localnet}/token:EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v`,
+  EurcMainnet: `${Network.Mainnet}/token:HzwqbKZw8HxMN6bF2yFZNrht3c2iXXzpKcFu7uBEDKtr`,
+  EurcDevnet: `${Network.Devnet}/token:HzwqbKZw8HxMN6bF2yFZNrht3c2iXXzpKcFu7uBEDKtr`,
+  EurcLocalnet: `${Network.Localnet}/token:HzwqbKZw8HxMN6bF2yFZNrht3c2iXXzpKcFu7uBEDKtr`,
+  Ai16zMainnet: `${Network.Mainnet}/token:HeLp6NuQkmYB4pYWo2zYs22mESHXPQYzXbB8n4V98jwC`,
+} as const;
+
+export type KnownCaip19Id = (typeof KnownCaip19Id)[keyof typeof KnownCaip19Id];
 
 export type NativeCaipAssetType = `${Network}/slip44:501`;
 export type TokenCaipAssetType = `${Network}/token:${string}`;
@@ -92,9 +96,12 @@ export const NETWORK_TO_EXPLORER_CLUSTER = {
   [Network.Localnet]: 'local',
 };
 
-export enum SolanaCaip19Tokens {
-  SOL = 'slip44:501',
-}
+export const SolanaCaip19Tokens = {
+  SOL: 'slip44:501',
+} as const;
+
+export type SolanaCaip19Tokens =
+  (typeof SolanaCaip19Tokens)[keyof typeof SolanaCaip19Tokens];
 
 export type TokenInfo = {
   symbol: string;