From 2c21ffab0339675e4577017f06ee01dd3852a4fc Mon Sep 17 00:00:00 2001
From: kyscott18 <43524469+kyscott18@users.noreply.github.com>
Date: Fri, 16 Aug 2024 17:53:35 -0400
Subject: [PATCH] fix cached from block (#1042)

* fix cached from block

* cleanup

* chore: changeset

* Update silver-lamps-tan.md

---------

Co-authored-by: typedarray <90073088+0xOlias@users.noreply.github.com>
---
 .changeset/silver-lamps-tan.md             |  5 +++++
 packages/core/src/sync-historical/index.ts | 18 ++++++++++++++----
 packages/core/src/utils/interval.test.ts   | 21 +++++++++++++++++++++
 packages/core/src/utils/interval.ts        |  4 ++++
 4 files changed, 44 insertions(+), 4 deletions(-)
 create mode 100644 .changeset/silver-lamps-tan.md

diff --git a/.changeset/silver-lamps-tan.md b/.changeset/silver-lamps-tan.md
new file mode 100644
index 000000000..5f845c0bd
--- /dev/null
+++ b/.changeset/silver-lamps-tan.md
@@ -0,0 +1,5 @@
+---
+"@ponder/core": patch
+---
+
+Fixed a regression introduced in `0.5.9` that sometimes caused events to be skipped during indexing if any `startBlock` was set earlier than in a previous indexing run. This issue did not affect the database integrity, but affected apps should restart to ensure all events are indexed.
diff --git a/packages/core/src/sync-historical/index.ts b/packages/core/src/sync-historical/index.ts
index 05f5e1b56..556df5d76 100644
--- a/packages/core/src/sync-historical/index.ts
+++ b/packages/core/src/sync-historical/index.ts
@@ -20,6 +20,7 @@ import {
   intervalDifference,
   intervalIntersection,
   intervalSum,
+  sortIntervals,
 } from "@/utils/interval.js";
 import { never } from "@/utils/never.js";
 import type { RequestQueue } from "@/utils/requestQueue.js";
@@ -89,12 +90,21 @@ export const createHistoricalSync = async (
    * some progress.
    */
   const _latestCompletedBlocks = args.sources.map(({ filter }) => {
-    const completedIntervals = intervalIntersection(
-      [[filter.fromBlock, filter.toBlock ?? Number.POSITIVE_INFINITY]],
-      intervalsCache.get(filter)!,
+    const requiredInterval = [
+      filter.fromBlock,
+      filter.toBlock ?? Number.POSITIVE_INFINITY,
+    ] satisfies Interval;
+    const cachedIntervals = intervalsCache.get(filter)!;
+
+    const completedIntervals = sortIntervals(
+      intervalIntersection([requiredInterval], cachedIntervals),
     );
+
     if (completedIntervals.length === 0) return undefined;
-    return completedIntervals[0]![1];
+
+    const earliestCompletedInterval = completedIntervals[0]!;
+    if (earliestCompletedInterval[0] !== filter.fromBlock) return undefined;
+    return earliestCompletedInterval[1];
   });
 
   if (_latestCompletedBlocks.every((block) => block !== undefined)) {
diff --git a/packages/core/src/utils/interval.test.ts b/packages/core/src/utils/interval.test.ts
index 1f737228c..3d7497efe 100644
--- a/packages/core/src/utils/interval.test.ts
+++ b/packages/core/src/utils/interval.test.ts
@@ -4,6 +4,7 @@ import {
   intervalIntersection,
   intervalSum,
   intervalUnion,
+  sortIntervals,
 } from "./interval.js";
 
 test("intervalSum handles empty input", () => {
@@ -194,3 +195,23 @@ test("intervalDifference does not mutate inputs", () => {
 
   expect(initial).toStrictEqual([6, 17]);
 });
+
+test("sortIntervals", () => {
+  let result = sortIntervals([
+    [1, 5],
+    [4, 7],
+  ]);
+  expect(result).toStrictEqual([
+    [1, 5],
+    [4, 7],
+  ]);
+
+  result = sortIntervals([
+    [4, 7],
+    [1, 5],
+  ]);
+  expect(result).toStrictEqual([
+    [1, 5],
+    [4, 7],
+  ]);
+});
diff --git a/packages/core/src/utils/interval.ts b/packages/core/src/utils/interval.ts
index 46c727864..6c409007f 100644
--- a/packages/core/src/utils/interval.ts
+++ b/packages/core/src/utils/interval.ts
@@ -164,6 +164,10 @@ export function intervalDifference(
   return result;
 }
 
+export function sortIntervals(intervals: Interval[]) {
+  return intervals.sort((a, b) => (a[0] < b[0] ? -1 : 1));
+}
+
 export function getChunks({
   interval,
   maxChunkSize,