fix(vat-bank): allow numeric or string nonces (#10929)

closes: #10928 
refs: #8544

## Description

The change in #8544 unintentionally disabled `vat-bank`'s vpurse balance notification feature.

### Security Considerations

Since the `vat-bank.js` on mainnet has not been upgraded to the code in #8544, the #10928 issue only pertains to new or upgraded instances of `vat-bank.js`, such as in CI, local chains, and testnet chains.  There is absolutely no impact if this PR is landed before the next `vat-bank.js` upgrade to #8544 code.

### Scaling Considerations

None.

### Documentation Considerations

None.

### Testing Considerations

A unit test would be beneficial, but is not yet implemented.

### Upgrade Considerations

As above, production chains should not upgrade their `vat-bank.js` to the code in current master until this PR lands.

packages/cosmic-swingset/src/types.d.ts

@@ -1,8 +1,5 @@
-import { QueuedActionType } from '@agoric/internal/src/action-types.js';
-import type {
-  CoreEval,
-  CoreEvalSDKType,
-} from '@agoric/cosmic-proto/agoric/swingset/swingset.js';
+import type { CoreEvalSDKType } from '@agoric/cosmic-proto/agoric/swingset/swingset.js';
+import type { BridgeBigInt } from '@agoric/internal';
 
 // TODO move `walletFlags.js` from @agoric/vats to @agoric/cosmic-proto
 type PowerFlag = 'SMART_WALLET' | 'REMOTE_WALLET';
@@ -11,10 +8,12 @@ type PowerFlag = 'SMART_WALLET' | 'REMOTE_WALLET';
 // structs or use some other shared type truth
 // https://github.com/Agoric/agoric-sdk/issues/8545
 
+export type { BridgeBigInt };
+
 interface ActionContext<T extends Uppercase<string>> {
   type: T;
-  blockHeight: string;
-  blockTime: string;
+  blockHeight: BridgeBigInt;
+  blockTime: BridgeBigInt;
 }
 
 /**
@@ -39,7 +38,7 @@ export type PleaseProvisionAction = ActionContext<'PLEASE_PROVISION'> & {
  * @see VbankBalanceUpdate in vbank.go
  */
 export type VbankBalanceUpdateAction = ActionContext<'VBANK_BALANCE_UPDATE'> & {
-  nonce: string;
+  nonce: BridgeBigInt;
   updated: Array<{ address: string; denom: string; amount: string }>;
 };
 

packages/internal/src/typeGuards.js

@@ -1,4 +1,5 @@
 // @jessie-check
+// @ts-check
 
 import { M } from '@endo/patterns';
 
@@ -11,3 +12,14 @@ export const UnguardedHelperI = M.interface(
   // not exposed so sloppy okay
   { sloppy: true },
 );
+
+/**
+ * @typedef {number | `${bigint}`} BridgeBigInt Ensure that callees passed a
+ *   bridge message that was serialised from a Golang int64 or uint64 accept
+ *   either a JS number or a stringified JS bigint.
+ */
+
+/**
+ * @type {import('./types.js').TypedPattern<BridgeBigInt>}
+ */
+export const BridgeBigIntShape = M.or(M.number(), M.string());

packages/internal/test/snapshots/exports.test.js.md

@@ -9,6 +9,7 @@ Generated by [AVA](https://avajs.dev).
 > Snapshot 1
 
     [
+      'BridgeBigIntShape',
       'BridgeId',
       'CosmosInitKeyToBridgeId',
       'NonNullish',

packages/vats/src/vat-bank.js

@@ -3,7 +3,7 @@ import { E, Far } from '@endo/far';
 import { M, getInterfaceGuardPayload } from '@endo/patterns';
 
 import { AmountMath, AssetKind, BrandShape } from '@agoric/ertp';
-import { deeplyFulfilledObject } from '@agoric/internal';
+import { deeplyFulfilledObject, BridgeBigIntShape } from '@agoric/internal';
 import { prepareGuardedAttenuator } from '@agoric/internal/src/callback.js';
 import {
   IterableEachTopicI,
@@ -23,8 +23,8 @@ import {
 
 /**
  * @import {Guarded} from '@endo/exo';
- * @import {Passable, RemotableObject} from '@endo/pass-style';
- * @import {BridgeMessage} from '@agoric/cosmic-swingset/src/types.js';
+ * @import {RemotableObject} from '@endo/pass-style';
+ * @import {BridgeMessage, BridgeBigInt} from '@agoric/cosmic-swingset/src/types.js';
  */
 
 const { VirtualPurseControllerI } = makeVirtualPurseKitIKit();
@@ -42,12 +42,12 @@ const BridgeChannelI = M.interface('BridgeChannel', {
 
 /**
  * @typedef {Guarded<{
- *   update: (value: string, nonce?: string) => void;
+ *   update: (value: string, nonce?: BridgeBigInt) => void;
  * }>} BalanceUpdater
  */
 
 const BalanceUpdaterI = M.interface('BalanceUpdater', {
-  update: M.call(M.string()).optional(M.string()).returns(),
+  update: M.call(M.string()).optional(BridgeBigIntShape).returns(),
 });
 
 /**
@@ -71,6 +71,10 @@ const prepareBalanceUpdater = zone =>
       lastBalanceUpdate: -1n,
     }),
     {
+      /**
+       * @param {string} value
+       * @param {BridgeBigInt} [nonce]
+       */
       update(value, nonce = undefined) {
         if (nonce !== undefined) {
           const thisBalanceUpdate = BigInt(nonce);

packages/vats/test/vat-bank.test.js

@@ -11,6 +11,7 @@ import { buildRootObject } from '../src/vat-bank.js';
 /**
  * @import {Remote} from '@agoric/internal';
  * @import {BridgeHandler, ScopedBridgeManager} from '../src/types.js';
+ * @import {VbankBalanceUpdateAction} from '@agoric/cosmic-swingset/src/types.js';
  */
 
 const { fakeVomKit } = reincarnate({ relaxDurabilityRules: false });
@@ -200,7 +201,14 @@ test('communication', async t => {
   const notifier = E(vpurse).getCurrentAmountNotifier();
   const updateRecord = await E(notifier).getUpdateSince();
   const balance = { address: 'agoricfoo', denom: 'ubld', amount: '92929' };
-  const obj = { type: 'VBANK_BALANCE_UPDATE', updated: [balance] };
+  /** @type {VbankBalanceUpdateAction} */
+  const obj = {
+    type: 'VBANK_BALANCE_UPDATE',
+    blockHeight: 992827,
+    nonce: 123,
+    blockTime: Date.now() / 1000,
+    updated: [balance],
+  };
   assert(bankHandler);
   await E(bankHandler).fromBridge(obj);