feat(shared): support Map and Set in toDisplayString

close #1067, close #1100

packages/shared/src/index.ts

@@ -11,6 +11,7 @@ export * from './domTagConfig'
 export * from './domAttrConfig'
 export * from './escapeHtml'
 export * from './looseEqual'
+export * from './toDisplayString'
 
 export const EMPTY_OBJ: { readonly [key: string]: any } = __DEV__
   ? Object.freeze({})
@@ -112,15 +113,6 @@ export const capitalize = cacheStringFunction(
 export const hasChanged = (value: any, oldValue: any): boolean =>
   value !== oldValue && (value === value || oldValue === oldValue)
 
-// For converting {{ interpolation }} values to displayed strings.
-export const toDisplayString = (val: unknown): string => {
-  return val == null
-    ? ''
-    : isArray(val) || (isPlainObject(val) && val.toString === objectToString)
-      ? JSON.stringify(val, null, 2)
-      : String(val)
-}
-
 export const invokeArrayFns = (fns: Function[], arg?: any) => {
   for (let i = 0; i < fns.length; i++) {
     fns[i](arg)

packages/shared/src/toDisplayString.ts

@@ -0,0 +1,28 @@
+import { isArray, isObject, isPlainObject } from './index'
+
+// For converting {{ interpolation }} values to displayed strings.
+export const toDisplayString = (val: unknown): string => {
+  return val == null
+    ? ''
+    : isObject(val)
+      ? JSON.stringify(val, replacer, 2)
+      : String(val)
+}
+
+const replacer = (_key: string, val: any) => {
+  if (val instanceof Map) {
+    return {
+      [`Map(${val.size})`]: [...val.entries()].reduce((entries, [key, val]) => {
+        ;(entries as any)[`${key} =>`] = val
+        return entries
+      }, {})
+    }
+  } else if (val instanceof Set) {
+    return {
+      [`Set(${val.size})`]: [...val.values()]
+    }
+  } else if (isObject(val) && !isArray(val) && !isPlainObject(val)) {
+    return String(val)
+  }
+  return val
+}