feat: support output plugins (#2916)

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### Description

<!-- Please insert your description here and provide especially info
about the "what" this PR is solving -->

examples/basic-vue/rolldown.config.js

@@ -8,4 +8,19 @@ export default defineConfig({
     // aligns with Vite in the future.
     conditionNames: ['import'],
   },
+  output: {
+    plugins: [
+      {
+        name: 'test-plugin',
+        outputOptions: function (options) {
+          console.log(options.banner)
+          options.banner = '/* banner */'
+          return options
+        },
+      },
+    ],
+  },
+  experimental: {
+    enableComposingJsPlugins: true,
+  },
 })

packages/rolldown/src/constants/plugin.ts

@@ -1,5 +1,15 @@
 import { Plugin } from '../plugin'
 
+export const ENUMERATED_OUTPUT_PLUGIN_HOOK_NAMES = [
+  'augmentChunkHash',
+  'outputOptions',
+  'renderChunk',
+  'renderStart',
+  'renderError',
+  'writeBundle',
+  'generateBundle',
+] as const
+
 export const ENUMERATED_PLUGIN_HOOK_NAMES = [
   // build hooks
   'options',
@@ -8,17 +18,11 @@ export const ENUMERATED_PLUGIN_HOOK_NAMES = [
   'load',
   'transform',
   'moduleParsed',
-  'augmentChunkHash',
   'buildEnd',
   'onLog',
   'resolveDynamicImport',
   // generate hooks
-  'generateBundle',
-  'outputOptions',
-  'renderChunk',
-  'renderStart',
-  'renderError',
-  'writeBundle',
+  ...ENUMERATED_OUTPUT_PLUGIN_HOOK_NAMES,
   'footer',
   'banner',
   'intro',

packages/rolldown/src/options/output-options.ts

@@ -4,6 +4,7 @@ import {
   SourcemapIgnoreListOption,
   SourcemapPathTransformOption,
 } from '../rollup'
+import { RolldownOutputPluginOption } from '../plugin'
 
 export type ModuleFormat =
   | 'es'
@@ -72,6 +73,7 @@ export interface OutputOptions {
    * - `preserve-legal`: preserve comments that contain `@license`, `@preserve` or starts with `//!` `/*!`
    */
   comments?: 'none' | 'preserve-legal'
+  plugins?: RolldownOutputPluginOption
 }
 
 interface OverwriteOutputOptionsForCli {

packages/rolldown/src/plugin/index.ts

@@ -301,6 +301,11 @@ export interface Plugin<A = any> extends OutputPlugin, Partial<PluginHooks> {
 
 export type RolldownPlugin<A = any> = Plugin<A> | BuiltinPlugin | ParallelPlugin
 export type RolldownPluginOption<A = any> = NullValue<RolldownPlugin<A>> | false
+export type RolldownOutputPlugin = OutputPlugin | BuiltinPlugin
+export type RolldownOutputPluginOption =
+  | NullValue<RolldownOutputPlugin>
+  | false
+  | RolldownOutputPluginOption[]
 // A recursive type definition for `RolldownPlugin`, this type is used internally for `config.plugins`
 export type RolldownPluginRec<A = any> =
   | RolldownPluginOption<A>

packages/rolldown/src/utils/create-bundler.ts

@@ -19,17 +19,29 @@ export async function createBundler(
     TreeshakingOptionsSchema.parse(inputOptions.treeshake)
   }
 
-  // Convert `RolldownPluginRec` to `RolldownPlugin`
-  let plugins = await normalizePluginOption(inputOptions.plugins)
+  const inputPlugins = await normalizePluginOption(inputOptions.plugins)
+
+  const outputPlugins = await normalizePluginOption(outputOptions.plugins)
+
+  // The `outputOptions` hook is called with the input plugins and the output plugins
+  outputOptions = pluginDriver.callOutputOptionsHook(
+    [...inputPlugins, ...outputPlugins],
+    outputOptions,
+  )
+
+  let plugins = [
+    ...inputPlugins,
+    // TODO give warning if `outputOptions.plugins` using build hooks
+    ...(await normalizePluginOption(outputOptions.plugins)),
+  ]
+
   if (inputOptions.experimental?.enableComposingJsPlugins ?? false) {
     plugins = composeJsPlugins(plugins)
   }
 
   const parallelPluginInitResult = await initializeParallelPlugins(plugins)
 
   try {
-    outputOptions = pluginDriver.callOutputOptionsHook(plugins, outputOptions)
-
     // Convert `NormalizedInputOptions` to `BindingInputOptions`
     const bindingInputOptions = bindingifyInputOptions(
       plugins,

packages/rolldown/src/utils/normalize-plugin-option.ts

@@ -1,10 +1,10 @@
 import { asyncFlatten } from './async-flatten'
-import type { RolldownPlugin } from '../plugin'
+import type { RolldownPlugin, RolldownOutputPlugin } from '../plugin'
 import type { InputOptions } from '../options/input-options'
-import type { OutputOptions, OutputPlugin } from '../rollup-types'
+import type { OutputOptions } from '../options/output-options'
 
 export const normalizePluginOption: {
   (plugins: InputOptions['plugins']): Promise<RolldownPlugin[]>
-  (plugins: OutputOptions['plugins']): Promise<OutputPlugin[]>
+  (plugins: OutputOptions['plugins']): Promise<RolldownOutputPlugin[]>
   (plugins: unknown): Promise<any[]>
 } = async (plugins: any) => (await asyncFlatten([plugins])).filter(Boolean)

packages/rolldown/tests/fixtures/plugin/output-plugins/_config.ts

@@ -0,0 +1,32 @@
+import { defineTest } from '@tests'
+import { getOutputChunk } from '@tests/utils'
+import { expect, vi } from 'vitest'
+
+const fn = vi.fn()
+const renderStartFn = vi.fn()
+
+export default defineTest({
+  skipComposingJsPlugin: true, // Here mutate the test config at non-skipComposingJsPlugin test will be next skipComposingJsPlugin test failed.
+  config: {
+    output: {
+      plugins: [
+        {
+          name: 'test-plugin',
+          outputOptions: function (options) {
+            expect(options.banner).toBeUndefined()
+            options.banner = '/* banner */'
+            fn()
+            return options
+          },
+          renderStart: renderStartFn,
+        },
+      ],
+    },
+  },
+  afterTest: (output) => {
+    expect(renderStartFn).toHaveBeenCalledTimes(1)
+    expect(fn).toHaveBeenCalledTimes(1)
+    const chunk = getOutputChunk(output)[0]
+    expect(chunk.code.includes('banner')).toBe(true)
+  },
+})

packages/rollup-tests/src/ignored-by-unsupported-features.md

@@ -129,6 +129,7 @@
 
 ### The `input.context` is not supported
  - rollup@form@custom-context: allows custom context@generates es
+ - rollup@function@options-in-renderstart: makes input and output options available in renderStart
 
 ### `output.dynamicImportInCjs` is not supported
  - rollup@function@dynamic-import-this-function: uses correct "this" in dynamic imports when not using arrow functions

packages/rollup-tests/src/ignored-tests.js

@@ -49,9 +49,6 @@ const ignoreTests = [
   "rollup@form@comment-before-import: preserves comments before imports@generates es",
   "rollup@form@comment-start-inside-comment: properly remove coments above import statements@generates es",
 
-  // The output plugins hooks is not working as expected
-  "rollup@function@options-in-renderstart: makes input and output options available in renderStart",
-
   // Nested plugin is not supported
   "rollup@function@nested-and-async-plugin: works when nested plugin",
 

packages/rollup-tests/src/status.json

@@ -1,8 +1,8 @@
 {
   "failed": 0,
   "skipFailed": 0,
-  "ignored": 38,
-  "ignored(unsupported features)": 402,
+  "ignored": 37,
+  "ignored(unsupported features)": 403,
   "ignored(treeshaking)": 285,
   "ignored(behavior passed, snapshot different)": 113,
   "passed": 680

packages/rollup-tests/src/status.md

@@ -2,8 +2,8 @@
 |----| ---- |
 | failed | 0 |
 | skipFailed | 0 |
-| ignored | 38 |
-| ignored(unsupported features) | 402 |
+| ignored | 37 |
+| ignored(unsupported features) | 403 |
 | ignored(treeshaking) | 285 |
 | ignored(behavior passed, snapshot different) | 113 |
 | passed | 680 |