refactor: share and normalize build output resolution

src/plugins/bytecode.ts

@@ -1,10 +1,10 @@
 import path from 'node:path'
 import { randomBytes } from 'node:crypto'
 import colors from 'picocolors'
-import { type Plugin, type LibraryOptions, type Rolldown, normalizePath } from 'vite'
+import { type Plugin, type Rolldown, normalizePath } from 'vite'
 import * as babel from '@babel/core'
 import MagicString from 'magic-string'
-import { toRelativePath } from '../utils'
+import { toRelativePath, resolveBuildOutputs } from '../utils'
 import type { BytecodeCompiler, BytecodeTarget } from '../bytecodeCompiler'
 
 // Inspired by https://github.com/bytenode/bytenode
@@ -140,10 +140,9 @@ export function bytecodePlugin(options: BytecodeOptions = {}): Plugin | null {
         return
       }
       const build = config.build
-      const resolvedOutputs = resolveBuildOutputs(build.rolldownOptions.output, build.lib)
+      const outputs = resolveBuildOutputs(build.rolldownOptions.output, build.lib)
-      if (resolvedOutputs) {
-        const outputs = Array.isArray(resolvedOutputs) ? resolvedOutputs : [resolvedOutputs]
       const output = outputs[0]
+      if (output) {
         if (output.format === 'es') {
           config.logger.warn(
             colors.yellow(
@@ -280,17 +279,6 @@ export function bytecodePlugin(options: BytecodeOptions = {}): Plugin | null {
   }
 }
 
-function resolveBuildOutputs(
-  outputs: Rolldown.OutputOptions | Rolldown.OutputOptions[] | undefined,
-  libOptions: LibraryOptions | false
-): Rolldown.OutputOptions | Rolldown.OutputOptions[] | undefined {
-  if (libOptions && !Array.isArray(outputs)) {
-    const libFormats = libOptions.formats || []
-    return libFormats.map(format => ({ ...outputs, format }))
-  }
-  return outputs
-}
-
 interface ProtectStringsPluginState extends babel.PluginPass {
   opts: { protectedStrings: Set<string> }
 }

src/plugins/electron.ts

@@ -2,9 +2,9 @@ import path from 'node:path'
 import fs from 'node:fs'
 import { builtinModules } from 'node:module'
 import colors from 'picocolors'
-import { type Plugin, type LibraryOptions, type Rolldown, type UserConfig, mergeConfig, normalizePath } from 'vite'
+import { type Plugin, type UserConfig, mergeConfig, normalizePath } from 'vite'
 import { getElectronNodeTarget, getElectronChromeTarget, supportESM } from '../electron'
-import { loadPackageData } from '../utils'
+import { loadPackageData, resolveBuildOutputs } from '../utils'
 
 export interface ElectronPluginOptions {
   root?: string
@@ -38,17 +38,6 @@ function processEnvDefine(): Record<string, string> {
   }
 }
 
-function resolveBuildOutputs(
-  outputs: Rolldown.OutputOptions | Rolldown.OutputOptions[] | undefined,
-  libOptions: LibraryOptions | false
-): Rolldown.OutputOptions | Rolldown.OutputOptions[] | undefined {
-  if (libOptions && !Array.isArray(outputs)) {
-    const libFormats = libOptions.formats || []
-    return libFormats.map(format => ({ ...outputs, format }))
-  }
-  return outputs
-}
-
 export function electronMainConfigPresetPlugin(options?: ElectronPluginOptions): Plugin {
   return {
     name: 'vite:electron-main-config-preset',
@@ -148,16 +137,15 @@ export function electronMainConfigValidatorPlugin(): Plugin {
         )
       }
 
-      const resolvedOutputs = resolveBuildOutputs(rolldownOptions.output, libOptions)
+      const outputs = resolveBuildOutputs(rolldownOptions.output, libOptions)
 
-      if (resolvedOutputs) {
+      if (outputs.length > 0) {
-        const outputs = Array.isArray(resolvedOutputs) ? resolvedOutputs : [resolvedOutputs]
         if (outputs.length > 1) {
           throw new Error('The electron vite main config does not support multiple outputs.')
         } else {
-          const outpout = outputs[0]
+          const output = outputs[0]
-          if (['es', 'cjs'].includes(outpout.format || '')) {
+          if (['es', 'cjs'].includes(output.format || '')) {
-            if (outpout.format === 'es' && !supportESM()) {
+            if (output.format === 'es' && !supportESM()) {
               throw new Error(
                 'The electron vite main config output format does not support "es", ' +
                   'you can upgrade electron to the latest version or switch to "cjs" format.'
@@ -232,12 +220,9 @@ export function electronPreloadConfigPresetPlugin(options?: ElectronPluginOption
       const buildConfig = mergeConfig(defaultConfig.build, build)
       config.build = buildConfig
 
-      const resolvedOutputs = resolveBuildOutputs(config.build.rolldownOptions!.output, config.build.lib || false)
+      const outputs = resolveBuildOutputs(config.build.rolldownOptions!.output, config.build.lib)
 
-      if (resolvedOutputs) {
+      if (outputs.some(({ format }) => format === 'es')) {
-        const outputs = Array.isArray(resolvedOutputs) ? resolvedOutputs : [resolvedOutputs]
-
-        if (outputs.find(({ format }) => format === 'es')) {
         if (Array.isArray(config.build.rolldownOptions!.output)) {
           config.build.rolldownOptions!.output.forEach(output => {
             if (output.format === 'es') {
@@ -252,7 +237,6 @@ export function electronPreloadConfigPresetPlugin(options?: ElectronPluginOption
             : path.posix.join(build.assetsDir || defaultConfig.build.assetsDir, '[name]-[hash].mjs')
         }
       }
-      }
 
       config.define = config.define || {}
       config.define = { ...processEnvDefine(), ...config.define }
@@ -302,16 +286,15 @@ export function electronPreloadConfigValidatorPlugin(): Plugin {
         )
       }
 
-      const resolvedOutputs = resolveBuildOutputs(rolldownOptions.output, libOptions)
+      const outputs = resolveBuildOutputs(rolldownOptions.output, libOptions)
 
-      if (resolvedOutputs) {
+      if (outputs.length > 0) {
-        const outputs = Array.isArray(resolvedOutputs) ? resolvedOutputs : [resolvedOutputs]
         if (outputs.length > 1) {
           throw new Error('The electron vite preload config does not support multiple outputs.')
         } else {
-          const outpout = outputs[0]
+          const output = outputs[0]
-          if (['es', 'cjs'].includes(outpout.format || '')) {
+          if (['es', 'cjs'].includes(output.format || '')) {
-            if (outpout.format === 'es' && !supportESM()) {
+            if (output.format === 'es' && !supportESM()) {
               throw new Error(
                 'The electron vite preload config output format does not support "es", ' +
                   'you can upgrade electron to the latest version or switch to "cjs" format.'

src/utils.ts

@@ -3,7 +3,7 @@ import path from 'node:path'
 import fs from 'node:fs'
 import { createHash } from 'node:crypto'
 import { createRequire } from 'node:module'
-import { loadEnv as viteLoadEnv } from 'vite'
+import { type LibraryOptions, type Rolldown, loadEnv as viteLoadEnv } from 'vite'
 
 export function isObject(value: unknown): value is Record<string, unknown> {
   return Object.prototype.toString.call(value) === '[object Object]'
@@ -32,6 +32,23 @@ export function toRelativePath(filename: string, importer: string): string {
   return relPath.startsWith('.') ? relPath : `./${relPath}`
 }
 
+/**
+ * Resolve configured build outputs into an array.
+ */
+export function resolveBuildOutputs(
+  outputs: Rolldown.OutputOptions | Rolldown.OutputOptions[] | undefined,
+  libOptions: LibraryOptions | false | undefined
+): Rolldown.OutputOptions[] {
+  if (Array.isArray(outputs)) {
+    return outputs
+  }
+  if (libOptions) {
+    const libFormats = libOptions.formats || []
+    return libFormats.map(format => ({ ...outputs, format }))
+  }
+  return outputs ? [outputs] : []
+}
+
 /**
  * Load `.env` files within the `envDir` (default: `process.cwd()`) .
  * By default, only env variables prefixed with `VITE_`, `MAIN_VITE_`, `PRELOAD_VITE_` and