add test for preserving order

types/tx.go

@@ -243,8 +243,9 @@ func sortedCopy(txs Txs) Txs {
 // Both lists must be sorted.
 func containsAnyTxs(a, b []Tx) (int, bool) {
 	aix, bix := 0, 0
+
+nextA:
 	for ; aix < len(a); aix++ {
-	LOOP:
 		for bix < len(b) {
 			switch bytes.Compare(b[bix], a[aix]) {
 			case 0:
@@ -259,7 +260,7 @@ func containsAnyTxs(a, b []Tx) (int, bool) {
 					return -1, false
 				}
 			case 1:
-				break LOOP
+				continue nextA
 			}
 		}
 	}

types/tx_test.go

@@ -158,4 +158,42 @@ func TestValidateTxRecordSet(t *testing.T) {
 		err := txrSet.Validate(100, []Tx{})
 		require.Error(t, err)
 	})
+	t.Run("TxRecordSet preserves order", func(t *testing.T) {
+		trs := []*abci.TxRecord{
+			{
+				Action: abci.TxRecord_ADDED,
+				Tx:     Tx([]byte{100}),
+			},
+			{
+				Action: abci.TxRecord_ADDED,
+				Tx:     Tx([]byte{99}),
+			},
+			{
+				Action: abci.TxRecord_ADDED,
+				Tx:     Tx([]byte{55}),
+			},
+			{
+				Action: abci.TxRecord_ADDED,
+				Tx:     Tx([]byte{12}),
+			},
+			{
+				Action: abci.TxRecord_ADDED,
+				Tx:     Tx([]byte{66}),
+			},
+			{
+				Action: abci.TxRecord_ADDED,
+				Tx:     Tx([]byte{9}),
+			},
+			{
+				Action: abci.TxRecord_ADDED,
+				Tx:     Tx([]byte{17}),
+			},
+		}
+		txrSet := NewTxRecordSet(trs)
+		err := txrSet.Validate(100, []Tx{})
+		require.NoError(t, err)
+		for i, tx := range txrSet.IncludedTxs() {
+			require.Equal(t, Tx(trs[i].Tx), tx)
+		}
+	})
 }