feat: defineInertInvitation

packages/fast-usdc/src/fast-usdc.contract.js

@@ -11,6 +11,7 @@ import { prepareLiquidityPoolKit } from './exos/liquidity-pool.js';
 import { prepareSettler } from './exos/settler.js';
 import { prepareStatusManager } from './exos/status-manager.js';
 import { prepareTransactionFeedKit } from './exos/transaction-feed.js';
+import { defineInertInvitation } from './utils/zoe.js';
 
 const trace = makeTracer('FastUsdc');
 
@@ -86,6 +87,11 @@ export const contract = async (zcf, privateArgs, zone, tools) => {
     { makeRecorderKit },
   );
 
+  const makeTestSubmissionInvitation = defineInertInvitation(
+    zcf,
+    'test of submitting evidence',
+  );
+
   const creatorFacet = zone.exo('Fast USDC Creator', undefined, {
     simulateFeesFromAdvance(amount, payment) {
       console.log('🚧🚧 UNTIL: advance fees are implemented 🚧🚧');
@@ -109,11 +115,7 @@ export const contract = async (zcf, privateArgs, zone, tools) => {
       // TODO(bootstrap integration): force this to throw and confirm that it
       // shows up in the the smart-wallet UpdateRecord `error` property
       feedKit.admin.submitEvidence(evidence);
-      return zcf.makeInvitation(async cSeat => {
-        trace('Offer made on noop invitation');
-        cSeat.exit();
-        return 'noop; evidence was pushed in the invitation maker call';
-      }, 'noop invitation');
+      return makeTestSubmissionInvitation();
     },
     makeDepositInvitation() {
       // eslint-disable-next-line no-use-before-define

packages/fast-usdc/src/utils/zoe.js

@@ -0,0 +1,28 @@
+import { makeTracer } from '@agoric/internal';
+
+const trace = makeTracer('ZoeUtils');
+
+/**
+ * Used for "continuing offer" invitations in which the caller does not need
+ * anything in return. In those cases there is no Zoe offer safety and the
+ * invitation making function can perform the request itself.
+ *
+ * But smart-wallet expects an invitation maker to make an invitation, so this
+ * function abstracts making such an inert invitation and logs consistently when
+ * it is used.
+ *
+ * When this is used by an invitation maker that performs the operation, receiving
+ * one of these invitations is evidence that the operation took place.
+ *
+ * @param {ZCF} zcf
+ * @param {string} description @see {@link ZCF.makeInvitation}
+ * @returns {() => Promise<Invitation>} an arg-less invitation maker
+ */
+export const defineInertInvitation = (zcf, description) => {
+  return () =>
+    zcf.makeInvitation(seat => {
+      trace(`ℹ️ An offer was made on an inert invitation for ${description}`);
+      seat.exit();
+      return 'inert; nothing should be expected from this offer';
+    }, description);
+};

packages/fast-usdc/test/fast-usdc.contract.test.ts

@@ -56,7 +56,7 @@ test('start', async t => {
   const seat = await E(zoe).offer(inv);
   t.is(
     await E(seat).getOfferResult(),
-    'noop; evidence was pushed in the invitation maker call',
+    'inert; nothing should be expected from this offer',
   );
 });