From 08f72a0fa86769ace5f70361c707b71ec3c8f654 Mon Sep 17 00:00:00 2001
From: yifei <lyfmagic99@gmail.com>
Date: Thu, 3 Sep 2020 09:14:51 +0800
Subject: [PATCH] set assigned keys when clear map

---
 __tests__/map-set.js  | 22 ++++++++++++++++++++++
 src/plugins/mapset.ts |  6 +++++-
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/__tests__/map-set.js b/__tests__/map-set.js
index faa46803..bbe9d479 100644
--- a/__tests__/map-set.js
+++ b/__tests__/map-set.js
@@ -244,5 +244,27 @@ function runBaseTest(name, useProxies, autoFreeze, useListener) {
 			expect(map1.has("key")).toBe(true)
 			expect(map1.get("key")).toBe(undefined)
 		})
+
+		test("#663 - clear map", () => {
+			const map = new Map([
+				["a", "b"],
+				["b", "c"]
+			])
+			const result = produceWithPatches(map, draft => {
+				draft.clear()
+			})
+
+			expect(result).toEqual([
+				new Map(),
+				[
+					{op: "remove", path: ["a"]},
+					{op: "remove", path: ["b"]}
+				],
+				[
+					{op: "add", path: ["a"], value: "b"},
+					{op: "add", path: ["b"], value: "c"}
+				]
+			])
+		})
 	})
 }
diff --git a/src/plugins/mapset.ts b/src/plugins/mapset.ts
index 8bb2d096..6dd579a7 100644
--- a/src/plugins/mapset.ts
+++ b/src/plugins/mapset.ts
@@ -15,7 +15,8 @@ import {
 	markChanged,
 	ProxyTypeMap,
 	ProxyTypeSet,
-	die
+	die,
+	each
 } from "../internal"
 
 export function enableMapSet() {
@@ -110,6 +111,9 @@ export function enableMapSet() {
 			prepareMapCopy(state)
 			markChanged(state)
 			state.assigned_ = new Map()
+			each(state.base_, key => {
+				state.assigned_!.set(key, false)
+			})
 			return state.copy_!.clear()
 		}