From 20fc721c4f6fb8991f47b2d8425092106e6a82e6 Mon Sep 17 00:00:00 2001
From: Haoqun Jiang <haoqunjiang@gmail.com>
Date: Mon, 15 Mar 2021 18:47:51 +0800
Subject: [PATCH 1/3] feat: a `defineConfig` API from `@vue/cli-service` for
 better type support in vue.config.js

Just like the API with the same name in Vite.
<https://vitejs.dev/config/>
---
 packages/@vue/cli-service/lib/Service.js   | 11 +++++++++++
 packages/@vue/cli-service/types/index.d.ts |  5 +++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/packages/@vue/cli-service/lib/Service.js b/packages/@vue/cli-service/lib/Service.js
index 2216adcfde..392ada2e36 100644
--- a/packages/@vue/cli-service/lib/Service.js
+++ b/packages/@vue/cli-service/lib/Service.js
@@ -436,3 +436,14 @@ function cloneRuleNames (to, from) {
     }
   })
 }
+
+/**
+ * @typedef {import('../types/index').ConfigFunction} ConfigFunction
+ * @typedef {import('../types/index').ProjectOptions} ProjectOptions
+ * @typedef {ProjectOptions|ConfigFunction} UserConfig
+ * @param {UserConfig} config
+ * @returns UserConfig
+ */
+module.exports.defineConfig = function defineConfig (config) {
+  return config
+}
diff --git a/packages/@vue/cli-service/types/index.d.ts b/packages/@vue/cli-service/types/index.d.ts
index dfb5e7f2d7..0bee1a3db8 100644
--- a/packages/@vue/cli-service/types/index.d.ts
+++ b/packages/@vue/cli-service/types/index.d.ts
@@ -3,7 +3,7 @@ import ChainableConfig = require('webpack-chain')
 import webpack = require('webpack')
 import WebpackDevServer = require('webpack-dev-server')
 import express = require('express') // @types/webpack-dev-server depends on @types/express
-import { ProjectOptions } from './ProjectOptions'
+import { ProjectOptions, ConfigFunction } from './ProjectOptions'
 
 type RegisterCommandFn = (args: minimist.ParsedArgs, rawArgv: string[]) => any
 
@@ -134,4 +134,5 @@ type ServicePlugin = (
 ) => any
 
 export { ProjectOptions, ServicePlugin, PluginAPI }
-export { ConfigFunction } from './ProjectOptions'
+type UserConfig = ProjectOptions | ConfigFunction
+export function defineConfig(config: UserConfig): UserConfig

From e2cf7cdbf45f775898689bbdde9697062541e234 Mon Sep 17 00:00:00 2001
From: Haoqun Jiang <haoqunjiang@gmail.com>
Date: Tue, 16 Mar 2021 16:05:26 +0800
Subject: [PATCH 2/3] chore: simplify the type annotation

---
 packages/@vue/cli-service/lib/Service.js | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/packages/@vue/cli-service/lib/Service.js b/packages/@vue/cli-service/lib/Service.js
index 392ada2e36..032f7069a5 100644
--- a/packages/@vue/cli-service/lib/Service.js
+++ b/packages/@vue/cli-service/lib/Service.js
@@ -437,13 +437,5 @@ function cloneRuleNames (to, from) {
   })
 }
 
-/**
- * @typedef {import('../types/index').ConfigFunction} ConfigFunction
- * @typedef {import('../types/index').ProjectOptions} ProjectOptions
- * @typedef {ProjectOptions|ConfigFunction} UserConfig
- * @param {UserConfig} config
- * @returns UserConfig
- */
-module.exports.defineConfig = function defineConfig (config) {
-  return config
-}
+/** @type {import('../types/index').defineConfig} */
+module.exports.defineConfig = (config) => config

From 628c1ffe94dc7faf68f1056daf22526df0e16b82 Mon Sep 17 00:00:00 2001
From: Haoqun Jiang <haoqunjiang@gmail.com>
Date: Wed, 17 Mar 2021 21:24:47 +0800
Subject: [PATCH 3/3] docs: mention `defineConfig` helper in the documentation

---
 docs/config/README.md    | 11 +++++++++++
 docs/zh/config/README.md | 12 ++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/docs/config/README.md b/docs/config/README.md
index b2a6f720a8..239c16412a 100644
--- a/docs/config/README.md
+++ b/docs/config/README.md
@@ -27,6 +27,17 @@ module.exports = {
 }
 ```
 
+Or, you can use the `defineConfig` helper from `@vue/cli-service`, which could provide better intellisense support:
+
+```js
+// vue.config.js
+const { defineConfig } = require('@vue/cli-service')
+
+module.exports = defineConfig({
+  // options...
+})
+```
+
 ### baseUrl
 
 Deprecated since Vue CLI 3.3, please use [`publicPath`](#publicPath) instead.
diff --git a/docs/zh/config/README.md b/docs/zh/config/README.md
index 752d3e5015..d3fb522d45 100644
--- a/docs/zh/config/README.md
+++ b/docs/zh/config/README.md
@@ -26,6 +26,18 @@ module.exports = {
   // 选项...
 }
 ```
+
+或者，你也可以使用 `@vue/cli-service` 提供的 `defineConfig` 帮手函数，以获得更好的类型提示：
+
+```js
+// vue.config.js
+const { defineConfig } = require('@vue/cli-service')
+
+module.exports = defineConfig({
+  // 选项
+})
+```
+
 ### baseUrl
 
 从 Vue CLI 3.3 起已弃用，请使用[`publicPath`](#publicpath)。