fix: useI18n wrong type and other type broken (#1309)

Author: kazupon

packages/core-base/src/context.ts

@@ -355,11 +355,22 @@ let _cid = 0
 export function createCoreContext<
   Message = string,
   Options extends CoreOptions<Message> = CoreOptions<Message>,
-  Messages = Options['messages'] extends object ? Options['messages'] : {},
-  DateTimeFormats = Options['datetimeFormats'] extends object
+  Messages extends Record<string, any> = Options['messages'] extends Record<
+    string,
+    any
+  >
+    ? Options['messages']
+    : {},
+  DateTimeFormats extends Record<
+    string,
+    any
+  > = Options['datetimeFormats'] extends Record<string, any>
     ? Options['datetimeFormats']
     : {},
-  NumberFormats = Options['numberFormats'] extends object
+  NumberFormats extends Record<
+    string,
+    any
+  > = Options['numberFormats'] extends Record<string, any>
     ? Options['numberFormats']
     : {}
 >(
@@ -379,12 +390,20 @@ export function createCoreContext<
     SchemaParams<Schema, Message>,
     LocaleParams<Locales>
   >,
-  Messages = Options['messages'] extends object ? Options['messages'] : {},
-  DateTimeFormats = Options['datetimeFormats'] extends object
-    ? Options['datetimeFormats']
+  Messages extends Record<string, any> = NonNullable<
+    Options['messages']
+  > extends Record<string, any>
+    ? NonNullable<Options['messages']>
     : {},
-  NumberFormats = Options['numberFormats'] extends object
-    ? Options['numberFormats']
+  DateTimeFormats extends Record<string, any> = NonNullable<
+    Options['datetimeFormats']
+  > extends Record<string, any>
+    ? NonNullable<Options['datetimeFormats']>
+    : {},
+  NumberFormats extends Record<string, any> = NonNullable<
+    Options['numberFormats']
+  > extends Record<string, any>
+    ? NonNullable<Options['numberFormats']>
     : {}
 >(
   options: Options

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

@@ -1750,23 +1750,20 @@ export function createComposer<
     SchemaParams<Schema, VueMessageType>,
     LocaleParams<Locales>
   >,
-  Messages extends Record<string, any> = Options['messages'] extends Record<
-    string,
-    any
-  >
-    ? Options['messages']
+  Messages extends Record<string, any> = NonNullable<
+    Options['messages']
+  > extends Record<string, any>
+    ? NonNullable<Options['messages']>
     : {},
-  DateTimeFormats extends Record<
-    string,
-    any
-  > = Options['datetimeFormats'] extends Record<string, any>
-    ? Options['datetimeFormats']
+  DateTimeFormats extends Record<string, any> = NonNullable<
+    Options['datetimeFormats']
+  > extends Record<string, any>
+    ? NonNullable<Options['datetimeFormats']>
     : {},
-  NumberFormats extends Record<
-    string,
-    any
-  > = Options['numberFormats'] extends Record<string, any>
-    ? Options['numberFormats']
+  NumberFormats extends Record<string, any> = NonNullable<
+    Options['numberFormats']
+  > extends Record<string, any>
+    ? NonNullable<Options['numberFormats']>
     : {}
 >(
   options: Options,

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

@@ -481,23 +481,20 @@ export function createI18n<
     SchemaParams<Schema, VueMessageType>,
     LocaleParams<Locales>
   > = I18nOptions<SchemaParams<Schema, VueMessageType>, LocaleParams<Locales>>,
-  Messages extends Record<string, unknown> = Options['messages'] extends Record<
-    string,
-    unknown
-  >
-    ? Options['messages']
+  Messages extends Record<string, unknown> = NonNullable<
+    Options['messages']
+  > extends Record<string, unknown>
+    ? NonNullable<Options['messages']>
     : {},
-  DateTimeFormats extends Record<
-    string,
-    unknown
-  > = Options['datetimeFormats'] extends Record<string, unknown>
-    ? Options['datetimeFormats']
+  DateTimeFormats extends Record<string, unknown> = NonNullable<
+    Options['datetimeFormats']
+  > extends Record<string, unknown>
+    ? NonNullable<Options['datetimeFormats']>
     : {},
-  NumberFormats extends Record<
-    string,
-    unknown
-  > = Options['numberFormats'] extends Record<string, unknown>
-    ? Options['numberFormats']
+  NumberFormats extends Record<string, unknown> = NonNullable<
+    Options['numberFormats']
+  > extends Record<string, unknown>
+    ? NonNullable<Options['numberFormats']>
     : {},
   OptionLocale = Options['locale'] extends string ? Options['locale'] : Locale
 >(
@@ -731,7 +728,7 @@ export function useI18n<Options extends UseI18nOptions = UseI18nOptions>(
   NonNullable<Options['messages']>,
   NonNullable<Options['datetimeFormats']>,
   NonNullable<Options['numberFormats']>,
-  NonNullable<Options['locale']>
+  Options['locale'] extends unknown ? string : Options['locale']
 >
 
 /**
@@ -803,7 +800,7 @@ export function useI18n<
   NonNullable<Options['messages']>,
   NonNullable<Options['datetimeFormats']>,
   NonNullable<Options['numberFormats']>,
-  NonNullable<Options['locale']>
+  Options['locale'] extends unknown ? string : Options['locale']
 >
 // eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
 export function useI18n<

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

@@ -1439,23 +1439,20 @@ export function createVueI18n<
     SchemaParams<Schema, VueMessageType>,
     LocaleParams<Locales>
   >,
-  Messages extends Record<string, any> = Options['messages'] extends Record<
-    string,
-    any
-  >
-    ? Options['messages']
+  Messages extends Record<string, any> = NonNullable<
+    Options['messages']
+  > extends Record<string, any>
+    ? NonNullable<Options['messages']>
     : {},
-  DateTimeFormats extends Record<
-    string,
-    any
-  > = Options['datetimeFormats'] extends Record<string, any>
-    ? Options['datetimeFormats']
+  DateTimeFormats extends Record<string, any> = NonNullable<
+    Options['datetimeFormats']
+  > extends Record<string, any>
+    ? NonNullable<Options['datetimeFormats']>
     : {},
-  NumberFormats extends Record<
-    string,
-    any
-  > = Options['numberFormats'] extends Record<string, any>
-    ? Options['numberFormats']
+  NumberFormats extends Record<string, any> = NonNullable<
+    Options['numberFormats']
+  > extends Record<string, any>
+    ? NonNullable<Options['numberFormats']>
     : {}
 >(
   options?: Options,

pnpm-lock.yaml

@@ -1,6 +1,6 @@
 /* eslint-disable @typescript-eslint/no-explicit-any */
-import { expectType } from './index'
-import { MessageType } from '../packages/runtime/dist/runtime'
+import { expectType } from '../index'
+import { MessageType } from '../../packages/core-base/src'
 
 /**
  * Message Type

test-d/runtime.test-d.ts renamed to test-d/core-base/runtime.test-d.ts

@@ -249,6 +249,13 @@ const globalComposer = useI18n<[ResourceSchema], 'en' | 'ja'>({
   useScope: 'global'
 })
 expect<string>(globalComposer.t('nest.bar', { foo: 1 }, { locale: 'ja' }))
+expect<'en' | 'ja'>(globalComposer.locale.value)
+
+// no annotation
+const localComposer = useI18n({
+  useScope: 'local'
+})
+expect<string>(localComposer.locale.value)
 
 expectType<I18nOptions>(looseOptions)
 expectType<