Rewrite references instead

Combines misc.d.ts and webpack.d.ts into `$$compiled.internal.d.ts`.

`$$compiled.internal.d.ts` represents type declarations necessary to type the implementation while `compiled.d.ts`
represents declarations necessary to type the emitted declarations.

This internal/public split is really just a typechecking perf improvement.

We should just be able to include both public and internal ambient declarations in the declaratione emit program
and then just test the internal one isn't referenced.

Author: eps1lon

packages/next/index.d.ts

@@ -1,5 +1,4 @@
 /// <reference types="./types/global" />
-/// <reference types="./types/compiled" />
 /// <reference path="./dist/styled-jsx/types/global.d.ts" />
 /// <reference path="./amp.d.ts" />
 /// <reference path="./app.d.ts" />

packages/next/taskfile.js

@@ -2576,7 +2576,10 @@ export async function trace(task, opts) {
 }
 
 export async function build(task, opts) {
-  await task.serial(['precompile', 'compile', 'generate_types'], opts)
+  await task.serial(
+    ['precompile', 'compile', 'generate_types', 'rewrite_compiled_references'],
+    opts
+  )
 }
 
 export async function generate_types(task, opts) {
@@ -2585,6 +2588,37 @@ export async function generate_types(task, opts) {
   })
 }
 
+/**
+ * TypeScript will emit references to the compiled types used to type the implementation.
+ * The declarations however don't need such detailed types.
+ * We rewrite the references to reference a more lightweight solution instead.
+ * @param {import('taskr').Task} task
+ */
+export async function rewrite_compiled_references(task, opts) {
+  const declarationDirectory = join(__dirname, 'dist')
+  const declarationFiles = glob.sync('**/*.d.ts', { cwd: declarationDirectory })
+
+  for (const declarationFile of declarationFiles) {
+    const content = await fs.readFile(
+      join(declarationDirectory, declarationFile),
+      'utf8'
+    )
+    // Rewrite
+    // /// <reference path="../../../../types/$$compiled.internal.d.ts" />
+    // to
+    // /// <reference path="../../../../types/compiled.d.ts" />
+    if (content.indexOf('/types/$$compiled.internal.d.ts" />') !== -1) {
+      await fs.writeFile(
+        join(declarationDirectory, declarationFile),
+        content.replace(
+          /\/types\/\$\$compiled\.internal\.d\.ts" \/>/g,
+          '/types/compiled.d.ts" />'
+        )
+      )
+    }
+  }
+}
+
 export default async function (task) {
   const opts = { dev: true }
   await task.clear('dist')

packages/next/types/misc.d.ts renamed to packages/next/types/$$compiled.internal.d.ts

@@ -446,3 +446,33 @@ declare module 'next/dist/compiled/zod' {
   import * as m from 'zod'
   export = m
 }
+
+declare module 'mini-css-extract-plugin'
+declare module 'next/dist/compiled/loader-utils3'
+
+declare module 'next/dist/compiled/webpack/webpack' {
+  import type webpackSources from 'webpack-sources1'
+  export function init(): void
+  export let BasicEvaluatedExpression: any
+  export let GraphHelpers: any
+  export let sources: typeof webpackSources
+  export let StringXor: any
+  export {
+    default as webpack,
+    Compiler,
+    Compilation,
+    Module,
+    Stats,
+    Template,
+    RuntimeModule,
+    RuntimeGlobals,
+    NormalModule,
+    ResolvePluginInstance,
+    ModuleFilenameHelpers,
+  } from 'webpack'
+  export type {
+    LoaderDefinitionFunction,
+    LoaderContext,
+    ModuleGraph,
+  } from 'webpack'
+}

packages/next/types/compiled.d.ts

@@ -8,3 +8,48 @@ declare module 'VAR_MODULE_GLOBAL_ERROR'
 declare module 'VAR_USERLAND'
 declare module 'VAR_MODULE_DOCUMENT'
 declare module 'VAR_MODULE_APP'
+
+declare module 'next/dist/compiled/webpack/webpack' {
+  export function init(): void
+  export let BasicEvaluatedExpression: any
+  export let GraphHelpers: any
+  export let sources: any
+  export let StringXor: any
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  export type LoaderDefinitionFunction<T> = any
+  namespace webpack {
+    export type Compiler = any
+    export type WebpackPluginInstance = any
+    export type Compilation = any
+    export type Module = any
+    export type Stats = any
+    export type Template = any
+    export type RuntimeModule = any
+    export type RuntimeGlobals = any
+    export type NormalModule = any
+    export type ResolvePluginInstance = any
+    export type Configuration = any
+    export type ResolveOptions = any
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    export type LoaderContext<T> = any
+    export type RuleSetUseItem = any
+    export type EntryObject = any
+    export type Chunk = any
+    export type ChunkGroup = any
+    export type DefinePlugin = any
+    // eslint-disable-next-line @typescript-eslint/no-shadow
+    namespace sources {
+      export type RawSource = any
+    }
+  }
+  export var webpack: any
+}
+
+declare module 'next/dist/compiled/superstruct' {
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  export type Struct<T, S> = any
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  export type Infer<T = any> = any
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  export type Describe<T> = any
+}