feat: charter for the PSM, enabling governance (#6090)

* feat: charter for the PSM, enabling governance

No tests are included.

* refactor: turn it into a continuing invitation

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

packages/governance/src/types.js

@@ -521,6 +521,7 @@
  * @typedef {object} GovernedContractFacetAccess
  * @property {VoteOnParamChanges} voteOnParamChanges
  * @property {VoteOnApiInvocation} voteOnApiInvocation
+ * @property {VoteOnOfferFilter} voteOnOfferFilter
  * @property {() => Promise<LimitedCreatorFacet<CF>>} getCreatorFacet - creator
  *   facet of the governed contract, without the tightly held ability to change
  *   param values.

packages/inter-protocol/src/psm/psmCharter.js

@@ -0,0 +1,80 @@
+// @ts-check
+
+import '@agoric/governance/src/exported.js';
+import '@agoric/zoe/exported.js';
+import '@agoric/zoe/src/contracts/exported.js';
+
+import { E, Far } from '@endo/far';
+
+/**
+ * @file
+ *
+ * This contract makes it possible for those who govern the PSM to call for
+ * votes on changes. A more complete implementation would validate parameters,
+ * constrain deadlines and possibly split the ability to call for votes into
+ * separate capabilities for finer grain encapsulation.
+ */
+
+/**
+ * @param {ZCF<{binaryVoteCounterInstallation:Installation}>} zcf
+ * @param {{psm:GovernedContractFacetAccess<{},{}>}} privateArgs
+ */
+export const start = async (zcf, privateArgs) => {
+  const { binaryVoteCounterInstallation: counter } = zcf.getTerms();
+  const { psm } = privateArgs;
+
+  const makeParamInvitaion = () => {
+    /**
+     * @param {Record<string, unknown>} params
+     * @param {bigint} deadline
+     * @param {{paramPath: { key: string }}} [path]
+     */
+    const voteOnParamChanges = (
+      params,
+      deadline,
+      path = { paramPath: { key: 'governedApi' } },
+    ) => {
+      return E(psm).voteOnParamChanges(counter, deadline, {
+        ...path,
+        changes: params,
+      });
+    };
+
+    return zcf.makeInvitation(
+      () => Far('param change hook', { voteOnParamChanges }),
+      'vote on param changes',
+    );
+  };
+
+  const makeOfferFilterInvitation = () => {
+    /**
+     * @param {string[]} strings
+     * @param {bigint} deadline
+     */
+    const voteOnOfferFilter = (strings, deadline) => {
+      return E(psm).voteOnOfferFilter(counter, deadline, strings);
+    };
+
+    return zcf.makeInvitation(
+      () => Far('offer filter hook', { voteOnOfferFilter }),
+      'vote on offer filter',
+    );
+  };
+
+  const invitationMakers = Far('PSM Invitation Makers', {
+    VoteOnParamChange: makeParamInvitaion,
+    VoteOnPauseOffers: makeOfferFilterInvitation,
+  });
+
+  const charterMemberHandler = seat => {
+    seat.exit();
+    return invitationMakers;
+  };
+
+  const creatorFacet = Far('psm charter creator', {
+    makeCharterMemberInvitation: () =>
+      zcf.makeInvitation(charterMemberHandler, 'PSM charter member invitation'),
+  });
+
+  return harden({ creatorFacet });
+};

packages/inter-protocol/test/psm/test-governedPsm.js

@@ -24,7 +24,6 @@ test('psm block offers w/Governance', async t => {
   const invitations = await E(committeeCreator).getVoterInvitations();
   const { governorCreatorFacet } = governor;
 
-  // @ts-expect-error undeclared type?
   const { details } = await E(governorCreatorFacet).voteOnOfferFilter(
     installs.counter,
     2n,