From 7576033134ee744e2d7739d05cedcd98c0bce1e8 Mon Sep 17 00:00:00 2001
From: Simon Warta <simon@warta.it>
Date: Mon, 2 Mar 2020 12:01:03 +0100
Subject: [PATCH] Fix order when merging results

---
 packages/bcp/src/cosmwasmconnection.ts | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/packages/bcp/src/cosmwasmconnection.ts b/packages/bcp/src/cosmwasmconnection.ts
index a7054e82..648ea7a0 100644
--- a/packages/bcp/src/cosmwasmconnection.ts
+++ b/packages/bcp/src/cosmwasmconnection.ts
@@ -60,7 +60,7 @@ function isDefined<X>(value: X | undefined): value is X {
   return value !== undefined;
 }
 
-function deduplicate<T>(input: ReadonlyArray<T>, comparator: (a: T, b: T) => number): ReadonlyArray<T> {
+function deduplicate<T>(input: ReadonlyArray<T>, comparator: (a: T, b: T) => number): Array<T> {
   const out = new Array<T>();
   for (const element of input) {
     if (!out.find(o => comparator(o, element) === 0)) {
@@ -70,6 +70,15 @@ function deduplicate<T>(input: ReadonlyArray<T>, comparator: (a: T, b: T) => num
   return out;
 }
 
+/** Compares transaxtion by height. If the height is equal, compare by hash to ensure deterministic order */
+function compareByHeightAndHash(a: TxsResponse, b: TxsResponse): number {
+  if (a.height === b.height) {
+    return a.txhash.localeCompare(b.txhash);
+  } else {
+    return parseInt(a.height, 10) - parseInt(b.height, 10);
+  }
+}
+
 /** Account and undefined are valid events. The third option means no event fired yet */
 type LastWatchAccountEvent = Account | undefined | "no_event_fired_yet";
 
@@ -362,7 +371,7 @@ export class CosmWasmConnection implements BlockchainConnection {
       }
       const responses = await Promise.all(pendingRequests);
       const allResults = responses.reduce((accumulator, results) => accumulator.concat(results), []);
-      txs = deduplicate(allResults, (a, b) => a.txhash.localeCompare(b.txhash));
+      txs = deduplicate(allResults, (a, b) => a.txhash.localeCompare(b.txhash)).sort(compareByHeightAndHash);
     } else {
       throw new Error("Unsupported query");
     }