fix: tweaks from review comments

packages/SwingSet/docs/static-vats.md

@@ -97,7 +97,7 @@ This is particularly useful for vats that implement a REPL, so operators can inc
 
 ### vat termination: `exitVat` and `exitVatWithFailure`
 
-A vat may signal to the kernel that it should be terminated at the end of its current crank.  Two powers are provided to do this: `exitVat(completion)` and `exitVatWithFailure(reason)`.  These powers will work in any vat but are primarily useful in dynamic vats.  The two differ in how the circumstances of termination are signalled to holders of the vat's `done` promise: `exitVat` fulfills that promise with the value provided in the `completion` parameter, whereas `exitVatWithFailure` rejects the promise with the value provided in the `reason` parameter.  Conventionally, `completion` will be a string and `reason` will be an `Error`, but any serializable object may be used for either.  After the crank in which either of these powers is invoked, no further messages will be delivered to the vat; instead, any such messages will be rejected with a `'vat terminated'` error.  Any outstanding promises for which the vat was the decider will also be rejected in the same way.  The vat and any resources it holds will become eligible for garbage collection.
+A vat may signal to the kernel that it should be terminated at the end of its current crank.  Two powers are provided to do this: `exitVat(completion)` and `exitVatWithFailure(reason)`.  These powers will work in any vat but are primarily useful in dynamic vats.  The two differ in how the circumstances of termination are signalled to holders of the vat's `done` promise: `exitVat` fulfills that promise with the value provided in the `completion` parameter, whereas `exitVatWithFailure` rejects the promise with the value provided in the `reason` parameter.  Conventionally, `completion` will be a string and `reason` will be an `Error`, but any serializable object may be used for either.  After the crank in which either of these powers is invoked, no further messages will be delivered to the vat; instead, any such messages will be rejected with a `'vat terminated'` error.  Any outstanding promises for which the vat was the decider will also be rejected in the same way.  The vat and any resources it holds will become eligible for garbage collection.  However, the crank itself will end normally, meaning that any actions taken by the vat during the crank in which either exit power was invoked will become part of the persisted state of the swingset, including messages that were sent from the vat during that crank (including, notably, actions taken _after_ the exit power was invoked but before the crank finished).
 
 ## Configuring Vats
 

packages/SwingSet/src/kernel/kernel.js

@@ -320,9 +320,8 @@ export default function buildKernel(
     insistCapData(info);
     if (kernelKeeper.getVatKeeper(vatID)) {
       const promisesToReject = kernelKeeper.cleanupAfterTerminatedVat(vatID);
-      const err = VAT_TERMINATION_ERROR;
       for (const kpid of promisesToReject) {
-        resolveToError(kpid, err, vatID);
+        resolveToError(kpid, VAT_TERMINATION_ERROR, vatID);
       }
       removeVatManager(vatID, shouldReject, info).then(
         () => kdebug(`terminated vat ${vatID}`),
@@ -334,7 +333,9 @@ export default function buildKernel(
   let terminationTrigger;
 
   function setTerminationTrigger(vatID, shouldAbortCrank, shouldReject, info) {
-    assert(!(shouldAbortCrank && !shouldReject));
+    if (shouldAbortCrank) {
+      assert(shouldReject);
+    }
     if (!terminationTrigger || shouldAbortCrank) {
       terminationTrigger = { vatID, shouldAbortCrank, shouldReject, info };
     }

packages/SwingSet/src/kernel/liveSlots.js

@@ -522,11 +522,11 @@ function build(
   }
 
   function exitVat(completion) {
-    syscall.exit(false, m.serialize(completion));
+    syscall.exit(false, m.serialize(harden(completion)));
   }
 
   function exitVatWithFailure(reason) {
-    syscall.exit(true, m.serialize(reason));
+    syscall.exit(true, m.serialize(harden(reason)));
   }
 
   // vats which use D are in: acorn-eventual-send, cosmic-swingset

packages/SwingSet/test/vat-admin/terminate/bootstrap-die-cleanly.js

@@ -15,7 +15,7 @@ export function buildRootObject() {
     },
     async phase2() {
       // terminate as a second phase, so we can capture the kernel state in between
-      E(dude.adminNode).terminate();
+      E(dude.adminNode).terminate('phase 2');
       await E(dude.adminNode).done();
     },
   });

packages/SwingSet/test/vat-admin/terminate/bootstrap-die-with-presence.js

@@ -0,0 +1,28 @@
+import { E } from '@agoric/eventual-send';
+
+export function buildRootObject(vatPowers) {
+  const { testLog } = vatPowers;
+
+  const self = harden({
+    async bootstrap(vats, devices) {
+      testLog('preparing dynamic vat');
+      const vatMaker = E(vats.vatAdmin).createVatAdminService(devices.vatAdmin);
+      const dude = await E(vatMaker).createVatByName('dude');
+      E(dude.root).dieReturningAPresence(self);
+      const doneP = E(dude.adminNode).done();
+      try {
+        const doneResult = await doneP;
+        testLog(`done message: ${doneResult.message}`);
+        await E(doneResult.emissary).talkBack('from beyond?');
+      } catch (e) {
+        testLog(`done exception ${e} (this should not happen)`);
+      }
+      testLog('done');
+    },
+
+    talkBack(arg) {
+      testLog(`talkback ${arg}`);
+    },
+  });
+  return self;
+}

packages/SwingSet/test/vat-admin/terminate/bootstrap-no-zombies.js

@@ -9,7 +9,7 @@ export function buildRootObject() {
       // sure everything is working
       const weatherwax = await E(vatMaker).createVatByName('weatherwax');
       await E(weatherwax.root).live();
-      E(weatherwax.adminNode).terminate();
+      E(weatherwax.adminNode).terminate('no zombies?');
       try {
         await E(weatherwax.adminNode).done();
       } catch (e) {

packages/SwingSet/test/vat-admin/terminate/bootstrap-speak-to-dead.js

@@ -37,7 +37,7 @@ export function buildRootObject(vatPowers) {
         testLog(`b: speak failed: ${e}`);
       }
 
-      E(weatherwax.adminNode).terminate();
+      E(weatherwax.adminNode).terminate('arbitrary reason');
       try {
         await E(weatherwax.adminNode).done();
       } catch (e) {

packages/SwingSet/test/vat-admin/terminate/bootstrap-terminate.js

@@ -59,12 +59,21 @@ export function buildRootObject(vatPowers, vatParameters) {
         case 'exceptionallyHappy':
           E(dude.root).dieHappy(Error(mode));
           break;
+        case 'happyTalkFirst':
+          E(dude.root).dieHappyButTalkToMeFirst(self, mode);
+          break;
         case 'sad':
           E(dude.root).dieSad(mode);
           break;
         case 'exceptionallySad':
           E(dude.root).dieSad(Error(mode));
           break;
+        case 'sadTalkFirst':
+          E(dude.root).dieSadButTalkToMeFirst(self, Error(mode));
+          break;
+        case 'dieReturningAPresence':
+          E(dude.root).dieReturningAPresence(self, Error(mode));
+          break;
         default:
           console.log('something terrible has happened');
           break;
@@ -77,7 +86,7 @@ export function buildRootObject(vatPowers, vatParameters) {
       );
       // then we try to kill the vat again, which should be idempotent
       if (mode === 'kill') {
-        E(dude.adminNode).terminate();
+        E(dude.adminNode).terminate('because we said so');
       }
 
       // the run-queue should now look like:
@@ -140,9 +149,9 @@ export function buildRootObject(vatPowers, vatParameters) {
       // proceed to the end of the test. We push the 'done' message to testLog
       try {
         const v = await doneP;
-        testLog(`done result ${v}`);
+        testLog(`done result ${v} (Error=${v instanceof Error})`);
       } catch (e) {
-        testLog(`done exception ${e}`);
+        testLog(`done exception ${e} (Error=${e instanceof Error})`);
       }
       testLog('done');
 

packages/SwingSet/test/vat-admin/terminate/swingset-die-with-presence.json

@@ -0,0 +1,13 @@
+{
+  "bootstrap": "bootstrap",
+  "bundles": {
+    "dude": {
+      "sourceSpec": "vat-dude-terminate.js"
+    }
+  },
+  "vats": {
+    "bootstrap": {
+      "sourceSpec": "bootstrap-die-with-presence.js"
+    }
+  }
+}

packages/SwingSet/test/vat-admin/terminate/test-terminate.js

@@ -25,7 +25,7 @@ test.before(async t => {
   t.context.data = { kernelBundles };
 });
 
-async function doTerminate(t, mode, reference) {
+async function doTerminate(t, mode, reference, extraMessage = []) {
   const configPath = path.resolve(__dirname, 'swingset-terminate.json');
   const config = loadSwingsetConfigFile(configPath);
   const controller = await buildVatController(config, [mode], t.context.data);
@@ -45,6 +45,7 @@ async function doTerminate(t, mode, reference) {
     'query2 2',
     'QUERY 3',
     'GOT QUERY 3',
+    ...extraMessage,
     'foreverP.catch Error: vat terminated',
     'query3P.catch Error: vat terminated',
     'foo4P.catch Error: vat terminated',
@@ -55,33 +56,64 @@ async function doTerminate(t, mode, reference) {
 }
 
 test('terminate', async t => {
-  await doTerminate(t, 'kill', 'done exception kill');
+  await doTerminate(t, 'kill', 'done exception kill (Error=false)');
 });
 
 test('exit happy path simple result', async t => {
-  await doTerminate(t, 'happy', 'done result happy');
+  await doTerminate(t, 'happy', 'done result happy (Error=false)');
 });
 
 test('exit happy path complex result', async t => {
   await doTerminate(
     t,
     'exceptionallyHappy',
-    'done result Error: exceptionallyHappy',
+    'done result Error: exceptionallyHappy (Error=true)',
   );
 });
 
 test('exit sad path simple result', async t => {
-  await doTerminate(t, 'sad', 'done exception sad');
+  await doTerminate(t, 'sad', 'done exception sad (Error=false)');
 });
 
 test('exit sad path complex result', async t => {
   await doTerminate(
     t,
     'exceptionallySad',
-    'done exception Error: exceptionallySad',
+    'done exception Error: exceptionallySad (Error=true)',
   );
 });
 
+test('exit happy path with ante-mortem message', async t => {
+  await doTerminate(
+    t,
+    'happyTalkFirst',
+    'done result happyTalkFirst (Error=false)',
+    ['GOT QUERY not dead quite yet'],
+  );
+});
+
+test('exit sad path with ante-mortem message', async t => {
+  await doTerminate(
+    t,
+    'sadTalkFirst',
+    'done exception Error: sadTalkFirst (Error=true)',
+    ['GOT QUERY not dead quite yet (but soon)'],
+  );
+});
+
+test('exit with presence', async t => {
+  const configPath = path.resolve(__dirname, 'swingset-die-with-presence.json');
+  const config = loadSwingsetConfigFile(configPath);
+  const controller = await buildVatController(config, [], t.context.data);
+  await controller.run();
+  t.deepEqual(controller.dump().log, [
+    'preparing dynamic vat',
+    'done message: your ad here',
+    'talkback from beyond?',
+    'done',
+  ]);
+});
+
 test('dispatches to the dead do not harm kernel', async t => {
   const configPath = path.resolve(__dirname, 'swingset-speak-to-dead.json');
   const config = loadSwingsetConfigFile(configPath);
@@ -99,7 +131,7 @@ test('dispatches to the dead do not harm kernel', async t => {
       `w: I ate'nt dead`,
       'b: p1b = I so resolve',
       'b: p2b fails Error: vat terminated',
-      'done: undefined',
+      'done: arbitrary reason',
     ]);
   }
   const state1 = getAllState(storage1);
@@ -122,7 +154,7 @@ test('dispatches to the dead do not harm kernel', async t => {
     t.deepEqual(c2.dump().log, [
       'b: p1b = I so resolve',
       'b: p2b fails Error: vat terminated',
-      'done: undefined',
+      'done: arbitrary reason',
       'm: live 2 failed: Error: vat terminated',
     ]);
   }

packages/SwingSet/test/vat-admin/terminate/vat-dude-terminate.js

@@ -24,6 +24,20 @@ export function buildRootObject(vatPowers) {
       vatPowers.exitVatWithFailure(reason);
     },
 
+    dieHappyButTalkToMeFirst(other, completion) {
+      vatPowers.exitVat(completion);
+      E(other).query('not dead quite yet');
+    },
+
+    dieSadButTalkToMeFirst(other, reason) {
+      vatPowers.exitVatWithFailure(reason);
+      E(other).query('not dead quite yet (but soon)');
+    },
+
+    dieReturningAPresence(other) {
+      vatPowers.exitVat({ message: 'your ad here', emissary: other });
+    },
+
     async elsewhere(other, arg) {
       testLog(`QUERY ${arg}`);
       const answer = await E(other).query(arg);