From c29f2c276fc621fe37abacb51e9d63a0b3f0e359 Mon Sep 17 00:00:00 2001
From: Chris Hibbert <hibbert@agoric.com>
Date: Sun, 5 Mar 2023 14:13:43 -0800
Subject: [PATCH] refactor: don't reschedule next if price is already locked

---
 .../inter-protocol/src/auction/scheduler.js   | 24 ++++++++++++++++---
 .../test/auction/test-computeRoundTiming.js   |  7 ++++++
 .../test/auction/test-scheduler.js            |  6 +++++
 3 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/packages/inter-protocol/src/auction/scheduler.js b/packages/inter-protocol/src/auction/scheduler.js
index 1fd25fdd1250..3dca74d03848 100644
--- a/packages/inter-protocol/src/auction/scheduler.js
+++ b/packages/inter-protocol/src/auction/scheduler.js
@@ -93,8 +93,17 @@ export const computeRoundTiming = (params, baseTime) => {
     startDelay,
   );
   const endTime = TimeMath.addAbsRel(startTime, actualDuration);
+  const lockTime = TimeMath.subtractAbsRel(startTime, lockPeriod);
 
-  const next = { startTime, endTime, steps, endRate, startDelay, clockStep };
+  const next = {
+    startTime,
+    endTime,
+    steps,
+    endRate,
+    startDelay,
+    clockStep,
+    lockTime,
+  };
   return harden(next);
 };
 
@@ -144,8 +153,17 @@ export const makeScheduler = async (
       auctionState = AuctionState.WAITING;
 
       auctionDriver.finalize();
-      const afterNow = TimeMath.addAbsRel(time, TimeMath.toRel(1n, timerBrand));
-      nextSchedule = computeRoundTiming(params, afterNow);
+
+      // only recalculate the next schedule at this point if the lock time has
+      // not been reached.
+      const nextLock = nextSchedule.lockTime;
+      if (TimeMath.compareAbs(time, nextLock) < 0) {
+        const afterNow = TimeMath.addAbsRel(
+          time,
+          TimeMath.toRel(1n, timerBrand),
+        );
+        nextSchedule = computeRoundTiming(params, afterNow);
+      }
       liveSchedule = undefined;
 
       E(timer).cancel(stepCancelToken);
diff --git a/packages/inter-protocol/test/auction/test-computeRoundTiming.js b/packages/inter-protocol/test/auction/test-computeRoundTiming.js
index 74ad93cf43f0..7bd9a0ba7ca0 100644
--- a/packages/inter-protocol/test/auction/test-computeRoundTiming.js
+++ b/packages/inter-protocol/test/auction/test-computeRoundTiming.js
@@ -47,6 +47,7 @@ const checkSchedule = (t, params, baseTime, rawExpect) => {
     endRate: rawExpect.endRate,
     startDelay: TimeMath.toRel(rawExpect.startDelay, brand),
     clockStep: TimeMath.toRel(rawExpect.clockStep, brand),
+    lockTime: TimeMath.toAbs(rawExpect.lockTime, brand),
   };
   t.deepEqual(schedule, expect);
 };
@@ -76,6 +77,7 @@ test('simple schedule', checkSchedule, makeDefaultParams(), 100, {
   endRate: 6_500n,
   startDelay: 300,
   clockStep: 600,
+  lockTime: 3000,
 });
 
 test(
@@ -90,6 +92,7 @@ test(
     endRate: 6_500n,
     startDelay: 300,
     clockStep: 600,
+    lockTime: 6600,
   },
 );
 
@@ -107,6 +110,7 @@ test(
     endRate: 6_500n,
     startDelay: 300,
     clockStep: 300,
+    lockTime: 3000,
   },
 );
 
@@ -155,6 +159,7 @@ test(
     endRate: 10_500n - 2_001n,
     startDelay: 300,
     clockStep: 600,
+    lockTime: 3000,
   },
 );
 
@@ -180,6 +185,7 @@ test(
     endRate: 10_500n - 5n * 10n,
     startDelay: 300,
     clockStep: 600,
+    lockTime: 3000,
   },
 );
 
@@ -197,5 +203,6 @@ test(
     endRate: 10_500n - 5n * 350n,
     startDelay: 300,
     clockStep: 600,
+    lockTime: 3000,
   },
 );
diff --git a/packages/inter-protocol/test/auction/test-scheduler.js b/packages/inter-protocol/test/auction/test-scheduler.js
index 5fd850c85fa1..5c64a1d110b0 100644
--- a/packages/inter-protocol/test/auction/test-scheduler.js
+++ b/packages/inter-protocol/test/auction/test-scheduler.js
@@ -69,6 +69,7 @@ test('schedule start to finish', async t => {
     endRate: 6500n,
     startDelay: TimeMath.toRel(1n, timerBrand),
     clockStep: TimeMath.toRel(2n, timerBrand),
+    lockTime: TimeMath.toAbs(126n, timerBrand),
   };
   t.deepEqual(schedule.nextAuctionSchedule, firstSchedule);
 
@@ -93,6 +94,7 @@ test('schedule start to finish', async t => {
     endRate: 6500n,
     startDelay: TimeMath.toRel(1n, timerBrand),
     clockStep: TimeMath.toRel(2n, timerBrand),
+    lockTime: TimeMath.toAbs(136, timerBrand),
   });
 
   t.is(fakeAuctioneer.getState().step, 1);
@@ -130,6 +132,7 @@ test('schedule start to finish', async t => {
     endRate: 6500n,
     startDelay: TimeMath.toRel(1n, timerBrand),
     clockStep: TimeMath.toRel(2n, timerBrand),
+    lockTime: TimeMath.toAbs(136n, timerBrand),
   };
   t.deepEqual(finalSchedule.nextAuctionSchedule, secondSchedule);
 
@@ -150,6 +153,7 @@ test('schedule start to finish', async t => {
     endRate: 6500n,
     startDelay: TimeMath.toRel(1n, timerBrand),
     clockStep: TimeMath.toRel(2n, timerBrand),
+    lockTime: TimeMath.toAbs(146n, timerBrand),
   });
 
   t.is(fakeAuctioneer.getState().step, 4);
@@ -521,6 +525,7 @@ test('duration = freq', async t => {
     endRate: 50n,
     startDelay: TimeMath.toRel(5n, timerBrand),
     clockStep: TimeMath.toRel(60n, timerBrand),
+    lockTime: TimeMath.toAbs(345n, timerBrand),
   };
   t.deepEqual(schedule.nextAuctionSchedule, firstSchedule);
 
@@ -535,6 +540,7 @@ test('duration = freq', async t => {
     endRate: 50n,
     startDelay: TimeMath.toRel(5n, timerBrand),
     clockStep: TimeMath.toRel(60n, timerBrand),
+    lockTime: TimeMath.toAbs(705n, timerBrand),
   };
   t.deepEqual(schedule.nextAuctionSchedule, secondSchedule);
 });