feat(build): emit license

docs/config/build-options.md

@@ -185,6 +185,52 @@ export default defineConfig({
 })
 ```
 
+## build.license
+
+- **Type:** `boolean | string`
+- **Default:** `false`
+
+When set to `true`, the build will also generate a `.vite/license.md` file that includes all bundled dependencies' licenses. It can be hosted to display and acknowledge the dependencies used by the app. When the value is a string, it will be used as the license file name. An example output may look like this:
+
+```md
+# Licenses
+
+The app bundles dependencies which contains the following licenses:
+
+## dep-1 - 1.2.3 (CC0-1.0)
+
+CC0 1.0 Universal
+
+...
+
+## dep-2 - 4.5.6 (MIT)
+
+MIT License
+
+...
+```
+
+If a string is passed that ends with `.json`, a raw JSON file will be generated instead. For example:
+
+```json
+[
+  {
+    "name": "dep-1",
+    "version": "1.2.3",
+    "identifier": "CC0-1.0",
+    "text": "CC0 1.0 Universal\n\n..."
+  },
+  {
+    "name": "dep-2",
+    "version": "4.5.6",
+    "identifier": "MIT",
+    "text": "MIT License\n\n..."
+  }
+]
+```
+
+It can be used for further processing to output as a different format.
+
 ## build.manifest
 
 - **Type:** `boolean | string`

packages/vite/src/node/__tests__/plugins/__snapshots__/license.spec.ts.snap

@@ -0,0 +1,47 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`json 1`] = `
+"[
+  {
+    "name": "@vitejs/test-dep-licence-cc0",
+    "version": "0.0.0",
+    "identifier": "CC0-1.0",
+    "text": "CC0 1.0 Universal\\n\\n..."
+  },
+  {
+    "name": "@vitejs/test-dep-license-mit",
+    "version": "0.0.0",
+    "identifier": "MIT",
+    "text": "MIT License\\n\\nCopyright (c) ..."
+  },
+  {
+    "name": "@vitejs/test-dep-nested-license-isc",
+    "version": "0.0.0",
+    "identifier": "ISC",
+    "text": "Copyright (c) ..."
+  }
+]"
+`;
+
+exports[`markdown 1`] = `
+"# Licenses
+
+The app bundles dependencies which contains the following licenses:
+
+## @vitejs/test-dep-licence-cc0 - 0.0.0 (CC0-1.0)
+
+CC0 1.0 Universal
+
+...
+
+## @vitejs/test-dep-license-mit - 0.0.0 (MIT)
+
+MIT License
+
+Copyright (c) ...
+
+## @vitejs/test-dep-nested-license-isc - 0.0.0 (ISC)
+
+Copyright (c) ...
+"
+`;

packages/vite/src/node/__tests__/plugins/esbuild.spec.ts

@@ -20,7 +20,6 @@ describe('resolveEsbuildTranspileOptions', () => {
       'es',
     )
     expect(options).toEqual({
-      charset: 'utf8',
       loader: 'js',
       target: 'es2020',
       format: 'esm',
@@ -64,7 +63,6 @@ describe('resolveEsbuildTranspileOptions', () => {
       'es',
     )
     expect(options).toEqual({
-      charset: 'utf8',
       loader: 'js',
       target: undefined,
       format: 'esm',
@@ -95,7 +93,6 @@ describe('resolveEsbuildTranspileOptions', () => {
       'es',
     )
     expect(options).toEqual({
-      charset: 'utf8',
       loader: 'js',
       target: 'es2020',
       format: 'esm',
@@ -128,7 +125,6 @@ describe('resolveEsbuildTranspileOptions', () => {
       'es',
     )
     expect(options).toEqual({
-      charset: 'utf8',
       loader: 'js',
       target: undefined,
       format: 'esm',
@@ -161,7 +157,6 @@ describe('resolveEsbuildTranspileOptions', () => {
       'cjs',
     )
     expect(options).toEqual({
-      charset: 'utf8',
       loader: 'js',
       target: undefined,
       format: 'cjs',
@@ -193,7 +188,6 @@ describe('resolveEsbuildTranspileOptions', () => {
       'es',
     )
     expect(options).toEqual({
-      charset: 'utf8',
       loader: 'js',
       target: undefined,
       format: 'esm',
@@ -229,7 +223,6 @@ describe('resolveEsbuildTranspileOptions', () => {
       'cjs',
     )
     expect(options).toEqual({
-      charset: 'utf8',
       loader: 'js',
       target: undefined,
       format: 'cjs',

packages/vite/src/node/__tests__/plugins/fixtures/license/dep-licence-cc0/index.js

@@ -0,0 +1 @@
+export default 'ok'

packages/vite/src/node/__tests__/plugins/fixtures/license/dep-licence-cc0/licence

@@ -0,0 +1,3 @@
+CC0 1.0 Universal
+
+...

packages/vite/src/node/__tests__/plugins/fixtures/license/dep-licence-cc0/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "@vitejs/test-dep-licence-cc0",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "license": "CC0-1.0"
+}

packages/vite/src/node/__tests__/plugins/fixtures/license/dep-license-mit/index.js

@@ -0,0 +1,3 @@
+import nestedDep from '@vitejs/test-dep-nested-licence-isc'
+
+export default 'ok' + nestedDep

packages/vite/src/node/__tests__/plugins/fixtures/license/dep-license-mit/license

@@ -0,0 +1,3 @@
+MIT License
+
+Copyright (c) ...

packages/vite/src/node/__tests__/plugins/fixtures/license/dep-license-mit/package.json

@@ -0,0 +1,10 @@
+{
+  "name": "@vitejs/test-dep-license-mit",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "license": "MIT",
+  "dependencies": {
+    "@vitejs/test-dep-nested-licence-isc": "file:../dep-nested-license-isc"
+  }
+}

packages/vite/src/node/__tests__/plugins/fixtures/license/dep-nested-license-isc/LICENSE

@@ -0,0 +1 @@
+Copyright (c) ...

packages/vite/src/node/__tests__/plugins/fixtures/license/dep-nested-license-isc/index.js

@@ -0,0 +1 @@
+export default 'ok'

packages/vite/src/node/__tests__/plugins/fixtures/license/dep-nested-license-isc/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "@vitejs/test-dep-nested-license-isc",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "license": "ISC"
+}

packages/vite/src/node/__tests__/plugins/fixtures/license/index.html

@@ -0,0 +1,5 @@
+<script type="module">
+  import dep1 from '@vitejs/test-dep-licence-cc0'
+  import dep2 from '@vitejs/test-dep-license-mit'
+  console.log(dep1, dep2)
+</script>

packages/vite/src/node/__tests__/plugins/fixtures/license/package.json

@@ -0,0 +1,10 @@
+{
+  "name": "@vitejs/test-license",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "dependencies": {
+    "@vitejs/test-dep-license-mit": "file:./dep-license-mit",
+    "@vitejs/test-dep-licence-cc0": "file:./dep-licence-cc0"
+  }
+}

packages/vite/src/node/__tests__/plugins/license.spec.ts

@@ -0,0 +1,36 @@
+import { fileURLToPath } from 'node:url'
+import type { OutputAsset, RollupOutput } from 'rollup'
+import { expect, test } from 'vitest'
+import { build } from '../../build'
+
+test('markdown', async () => {
+  const result = (await build({
+    root: fileURLToPath(new URL('./fixtures/license', import.meta.url)),
+    logLevel: 'silent',
+    build: {
+      write: false,
+      license: true,
+    },
+  })) as RollupOutput
+  const licenseAsset = result.output.find(
+    (asset) => asset.fileName === '.vite/license.md',
+  ) as OutputAsset | undefined
+  expect(licenseAsset).toBeDefined()
+  expect(licenseAsset?.source).toMatchSnapshot()
+})
+
+test('json', async () => {
+  const result = (await build({
+    root: fileURLToPath(new URL('./fixtures/license', import.meta.url)),
+    logLevel: 'silent',
+    build: {
+      write: false,
+      license: '.vite/license.json',
+    },
+  })) as RollupOutput
+  const licenseAsset = result.output.find(
+    (asset) => asset.fileName === '.vite/license.json',
+  ) as OutputAsset | undefined
+  expect(licenseAsset).toBeDefined()
+  expect(licenseAsset?.source).toMatchSnapshot()
+})

packages/vite/src/node/build.ts

@@ -73,6 +73,7 @@ import {
 } from './baseEnvironment'
 import type { MinimalPluginContext, Plugin, PluginContext } from './plugin'
 import type { RollupPluginHooks } from './typeUtils'
+import { licensePlugin } from './plugins/license'
 
 export interface BuildEnvironmentOptions {
   /**
@@ -199,6 +200,12 @@ export interface BuildEnvironmentOptions {
    * @default true
    */
   copyPublicDir?: boolean
+  /**
+   * Whether to emit a `.vite/license.md` file that includes all bundled dependencies'
+   * licenses. Specify a path that ends with `.json` to generate a raw JSON entry.
+   * @default false
+   */
+  license?: boolean | string
   /**
    * Whether to emit a .vite/manifest.json under assets dir to map hash-less filenames
    * to their hashed versions. Useful when you want to generate your own HTML
@@ -383,6 +390,7 @@ export function resolveBuildEnvironmentOptions(
     write: true,
     emptyOutDir: null,
     copyPublicDir: true,
+    license: false,
     manifest: false,
     lib: false,
     ssr: consumer === 'server',
@@ -501,7 +509,12 @@ export async function resolveBuildPlugins(config: ResolvedConfig): Promise<{
       ...(config.esbuild !== false ? [buildEsbuildPlugin(config)] : []),
       terserPlugin(config),
       ...(!config.isWorker
-        ? [manifestPlugin(), ssrManifestPlugin(), buildReporterPlugin(config)]
+        ? [
+            licensePlugin(),
+            manifestPlugin(),
+            ssrManifestPlugin(),
+            buildReporterPlugin(config),
+          ]
         : []),
       buildLoadFallbackPlugin(),
     ],

packages/vite/src/node/config.ts

@@ -1243,6 +1243,9 @@ export async function resolveConfig(
         ? false
         : {
             jsxDev: !isProduction,
+            // change defaults that fit better for vite
+            charset: 'utf8',
+            legalComments: 'none',
             ...config.esbuild,
           },
     server,

packages/vite/src/node/optimizer/index.ts

@@ -798,6 +798,7 @@ async function prepareEsbuildOptimizerRun(
     metafile: true,
     plugins,
     charset: 'utf8',
+    legalComments: 'none',
     ...esbuildOptions,
     supported: {
       ...defaultEsbuildSupported,

packages/vite/src/node/plugins/css.ts

@@ -1926,7 +1926,7 @@ function resolveMinifyCssEsbuildOptions(
   options: ESBuildOptions,
 ): TransformOptions {
   const base: TransformOptions = {
-    charset: options.charset ?? 'utf8',
+    charset: options.charset,
     logLevel: options.logLevel,
     logLimit: options.logLimit,
     logOverride: options.logOverride,

packages/vite/src/node/plugins/define.ts

@@ -191,7 +191,7 @@ export async function replaceDefine(
 
   const result = await transform(code, {
     loader: 'js',
-    charset: esbuildOptions.charset ?? 'utf8',
+    charset: esbuildOptions.charset,
     platform: 'neutral',
     define,
     sourcefile: id,

packages/vite/src/node/plugins/esbuild.ts

@@ -248,7 +248,6 @@ export function esbuildPlugin(config: ResolvedConfig): Plugin {
   // and for build as the final optimization is in `buildEsbuildPlugin`
   const transformOptions: TransformOptions = {
     target: 'esnext',
-    charset: 'utf8',
     ...esbuildTransformOptions,
     minify: false,
     minifyIdentifiers: false,
@@ -390,7 +389,6 @@ export function resolveEsbuildTranspileOptions(
   const esbuildOptions = config.esbuild || {}
 
   const options: TransformOptions = {
-    charset: 'utf8',
     ...esbuildOptions,
     loader: 'js',
     target: target || undefined,