Reset fill history when editing partially filled orders

matching-engine/matching-engine-core/src/main/kotlin/co/nilin/opex/matching/engine/core/engine/SimpleOrderBook.kt

@@ -250,7 +250,7 @@ class SimpleOrderBook(val pair: Pair, var replayMode: Boolean) : OrderBook {
             order.matchConstraint,
             order.orderType,
             order.direction,
-            order.filledQuantity,
+            0,
             null,
             null,
             null
@@ -613,4 +613,4 @@ class SimpleOrderBook(val pair: Pair, var replayMode: Boolean) : OrderBook {
         """.trimIndent()
         )
     }
-}
+}

matching-engine/matching-engine-core/src/test/kotlin/co/nilin/opex/matching/engine/core/SimpleOrderBookUnitTest.kt

@@ -564,6 +564,64 @@ class SimpleOrderBookUnitTest {
         Assertions.assertNull(orderBook.bestAskOrder)
     }
 
+    @Test
+    fun givenPartiallyFilledOrder_whenEditQuantity_thenRequestedQuantityRests() {
+        val orderBook = SimpleOrderBook(pair, false)
+        val ask = orderBook.handleNewOrderCommand(
+            OrderCreateCommand(
+                UUID.randomUUID().toString(),
+                uuid,
+                pair,
+                100,
+                10,
+                OrderDirection.ASK,
+                MatchConstraint.GTC,
+                OrderType.LIMIT_ORDER
+            )
+        )!!
+        orderBook.handleNewOrderCommand(
+            OrderCreateCommand(
+                UUID.randomUUID().toString(),
+                uuid,
+                pair,
+                100,
+                4,
+                OrderDirection.BID,
+                MatchConstraint.GTC,
+                OrderType.LIMIT_ORDER
+            )
+        )
+
+        val edited = orderBook.handleEditCommand(
+            OrderEditCommand(
+                UUID.randomUUID().toString(),
+                uuid,
+                ask.id()!!,
+                pair,
+                101,
+                6
+            )
+        ) as SimpleOrder
+
+        Assertions.assertEquals(0, edited.filledQuantity)
+        Assertions.assertEquals(6, edited.remainedQuantity())
+        Assertions.assertEquals(6, orderBook.askOrders[101]?.totalQuantity)
+
+        val aggressor = orderBook.handleNewOrderCommand(
+            OrderCreateCommand(
+                UUID.randomUUID().toString(),
+                uuid,
+                pair,
+                101,
+                6,
+                OrderDirection.BID,
+                MatchConstraint.IOC,
+                OrderType.LIMIT_ORDER
+            )
+        ) as SimpleOrder
+        Assertions.assertEquals(6, aggressor.filledQuantity)
+    }
+
     @Test
     fun givenEmptyOrderBook_whenGtcBidMarketOrderCreated_thenRejected() {
         //given
@@ -849,4 +907,4 @@ class SimpleOrderBookUnitTest {
         Assertions.assertNotNull(orderBook.bestBidOrder)
         Assertions.assertNotNull(orderBook.bestAskOrder)
     }
-}
+}