improvement/flag-for-vue-i18n-bridge (#705)

Author: kazupon

packages/vue-i18n-core/src/composer.ts

@@ -49,7 +49,8 @@ import {
   EnableEmitter,
   DisableEmitter,
   SetPluralRulesSymbol,
-  LegacyInstanceSymbol
+  LegacyInstanceSymbol,
+  __VUE_I18N_BRIDGE__
 } from './symbols'
 import { deepCopy, getLocaleMessages, getComponentOptions } from './utils'
 import { VERSION } from './misc'
@@ -1905,7 +1906,8 @@ export function createComposer(options: any = {}, VueI18nLegacy?: any): any {
         ? _warnHtmlMessage
           ? 'warn'
           : 'off'
-        : 'off'
+        : 'off',
+      __VUE_I18N_BRIDGE__
     }
     __legacy = new VueI18nLegacy(legacyOptions)
   }

packages/vue-i18n-core/src/i18n.ts

@@ -20,7 +20,12 @@ import { createComposer } from './composer'
 import { createVueI18n } from './legacy'
 import { I18nWarnCodes, getWarnMessage } from './warnings'
 import { I18nErrorCodes, createI18nError } from './errors'
-import { EnableEmitter, DisableEmitter, LegacyInstanceSymbol } from './symbols'
+import {
+  EnableEmitter,
+  DisableEmitter,
+  LegacyInstanceSymbol,
+  __VUE_I18N_BRIDGE__
+} from './symbols'
 import { apply } from './plugin'
 import { defineMixin as defineMixinNext } from './mixins/next'
 import { defineMixin as defineMixinBridge } from './mixins/bridge'
@@ -769,7 +774,7 @@ export function useI18n<
  * @VueI18nGeneral
  */
 export const castToVueI18n = /* #__PURE__*/ (i18n: I18n): VueI18n => {
-  if (!isLegacyVueI18n(i18n)) {
+  if (!(__VUE_I18N_BRIDGE__ in i18n)) {
     throw createI18nError(I18nErrorCodes.NOT_COMPATIBLE_LEGACY_VUE_I18N)
   }
   return i18n as unknown as VueI18n

packages/vue-i18n-core/src/legacy.ts

@@ -2,7 +2,7 @@
 import { createComposer, DefineLocaleMessage } from './composer'
 import { I18nWarnCodes, getWarnMessage } from './warnings'
 import { createI18nError, I18nErrorCodes } from './errors'
-import { EnableEmitter, DisableEmitter } from './symbols'
+import { EnableEmitter, DisableEmitter, __VUE_I18N_BRIDGE__ } from './symbols'
 import { DEFAULT_LOCALE } from '@intlify/core-base'
 import {
   isString,
@@ -15,7 +15,6 @@ import {
   assign,
   warn
 } from '@intlify/shared'
-import { isLegacyVueI18n } from './utils'
 
 import type {
   Path,
@@ -1464,9 +1463,7 @@ export function createVueI18n(options: any = {}, VueI18nLegacy?: any): any {
   type Message = VueMessageType
 
   if (__BRIDGE__) {
-    if (!isLegacyVueI18n(VueI18nLegacy)) {
-      throw createI18nError(I18nErrorCodes.NOT_COMPATIBLE_LEGACY_VUE_I18N)
-    }
+    options[__VUE_I18N_BRIDGE__] = __VUE_I18N_BRIDGE__ // marking
     return new VueI18nLegacy(options)
   } else {
     const composer = createComposer(convertComposerOptions(options)) as Composer

packages/vue-i18n-core/src/mixins/bridge.ts

@@ -37,7 +37,7 @@ export function defineMixin(
                   ? options.i18n.messages
                   : {}
               ;(options.__i18n as string[]).forEach(resource =>
-                deepCopy(localeMessages, JSON.parse(resource))
+                deepCopy(JSON.parse(resource), localeMessages)
               )
               Object.keys(localeMessages).forEach((locale: Locale) => {
                 options.i18n.mergeLocaleMessage(locale, localeMessages[locale])
@@ -82,7 +82,7 @@ export function defineMixin(
                   ? options.i18n.messages
                   : {}
               ;(options.__i18n as string[]).forEach(resource =>
-                deepCopy(localeMessages, JSON.parse(resource))
+                deepCopy(JSON.parse(resource), localeMessages)
               )
               options.i18n.messages = localeMessages
             } catch (e) {
@@ -94,7 +94,7 @@ export function defineMixin(
 
           const { sharedMessages } = options.i18n
           if (sharedMessages && isPlainObject(sharedMessages)) {
-            deepCopy(options.i18n.messages, sharedMessages)
+            deepCopy(sharedMessages, options.i18n.messages)
           }
 
           this._i18n = new VueI18n(options.i18n)

packages/vue-i18n-core/src/symbols.ts

@@ -9,3 +9,5 @@ export const DisableEmitter = /* #__PURE__*/ makeSymbol('__disableEmitter')
 export const SetPluralRulesSymbol = makeSymbol('__setPluralRules')
 export const DevToolsMetaSymbol = makeSymbol('__intlifyMeta')
 export const LegacyInstanceSymbol = /* #__PURE__*/ makeSymbol('__legacyVueI18n')
+
+export const __VUE_I18N_BRIDGE__ = /* #__PURE__*/ '__VUE_I18N_BRIDGE__'

packages/vue-i18n-core/test/i18n.test.ts

@@ -22,6 +22,7 @@ import {
 import { createEmitter } from '@intlify/shared'
 import { mount, pluralRules as _pluralRules } from './helper'
 import { createI18n, useI18n, castToVueI18n } from '../src/i18n'
+import { __VUE_I18N_BRIDGE__ } from '../src/symbols'
 import { errorMessages, I18nErrorCodes } from '../src/errors'
 import { Composer } from '../src/composer'
 
@@ -942,7 +943,7 @@ test('Intlify devtools hooking', () => {
 describe('castToVueI18n', () => {
   test('succeeded', () => {
     const mockVueI18n = {
-      version: '8.2.0'
+      __VUE_I18N_BRIDGE__
     } as unknown as I18n
     expect(castToVueI18n(mockVueI18n)).toBe(mockVueI18n)
   })