feat: shebang support

resolves #27

package.json

@@ -7,10 +7,9 @@
   "exports": "./dist/index.mjs",
   "types": "dist/index.d.ts",
   "bin": {
-    "unbuild": "./bin/unbuild.mjs"
+    "unbuild": "./dist/cli.mjs"
   },
   "files": [
-    "bin",
     "dist"
   ],
   "scripts": {

src/builder/plugins/shebang.ts

@@ -0,0 +1,60 @@
+import { promises as fsp } from 'fs'
+import MagicString from 'magic-string'
+import { resolve } from 'pathe'
+import type { Plugin } from 'rollup'
+
+// Forked from https://github.com/developit/rollup-plugin-preserve-shebang (1.0.1 @ MIT)
+
+const SHEBANG_RE = /^#![^\n]*/
+
+export interface ShebangPluginOptions {
+  preserve?: Boolean
+}
+
+export function shebangPlugin (options: ShebangPluginOptions = {}): Plugin {
+  const shebangs = new Map()
+  return {
+    name: 'unbuild-shebang',
+    // @ts-ignore temp workaround
+    _options: options,
+    transform (code, mod) {
+      let shebang
+      code = code.replace(SHEBANG_RE, (match) => {
+        shebang = match
+        return ''
+      })
+      if (!shebang) { return null }
+      shebangs.set(mod, shebang)
+      return { code, map: null }
+    },
+    renderChunk (code, chunk, { sourcemap }) {
+      if (options.preserve === false) { return null }
+      const shebang = shebangs.get(chunk.facadeModuleId)
+      if (!shebang) { return null }
+      const s = new MagicString(code)
+      s.prepend(`${shebang}\n`)
+      return {
+        code: s.toString(),
+        map: sourcemap ? s.generateMap({ hires: true }) : null
+      }
+    },
+    async writeBundle (options, bundle) {
+      for (const [fileName, output] of Object.entries(bundle)) {
+        if (output.type !== 'chunk') { continue }
+        if (output.code?.match(SHEBANG_RE)) {
+          const outFile = resolve(options.dir!, fileName)
+          await makeExecutable(outFile)
+        }
+      }
+    }
+  }
+}
+
+export async function makeExecutable (filePath: string) {
+  await fsp.chmod(filePath, 0o755 /* rwx r-x r-x */).catch(() => {})
+}
+
+export function getShebang (code: string, append = '\n') {
+  const m = code.match(SHEBANG_RE)
+  return m ? m + append : ''
+}

src/builder/rollup.ts

@@ -1,4 +1,5 @@
 import { writeFile } from 'fs/promises'
+import { promises as fsp } from 'fs'
 import type { RollupOptions, OutputOptions, OutputChunk } from 'rollup'
 import { rollup } from 'rollup'
 import commonjs from '@rollup/plugin-commonjs'
@@ -8,11 +9,12 @@ import _esbuild from 'rollup-plugin-esbuild'
 import dts from 'rollup-plugin-dts'
 import { relative, resolve } from 'pathe'
 import consola from 'consola'
-import { getpkg } from '../utils'
+import { getpkg, tryResolve } from '../utils'
 import type { BuildContext } from '../types'
 import { JSONPlugin } from './plugins/json'
 import { rawPlugin } from './plugins/raw'
 import { cjsPlugin } from './plugins/cjs'
+import { shebangPlugin, makeExecutable, getShebang } from './plugins/shebang'
 
 // @ts-ignore https://github.com/unjs/unbuild/issues/23
 const esbuild = _esbuild.default || _esbuild
@@ -21,11 +23,21 @@ export async function rollupBuild (ctx: BuildContext) {
   if (ctx.options.stub) {
     for (const entry of ctx.options.entries.filter(entry => entry.builder === 'rollup')) {
       const output = resolve(ctx.options.rootDir, ctx.options.outDir, entry.name!)
+
+      const resolvedEntry = tryResolve(entry.input, ctx.options.rootDir) || entry.input
+      const code = await fsp.readFile(resolvedEntry, 'utf8')
+      const shebang = getShebang(code)
+
       if (ctx.options.rollup.emitCJS) {
-        await writeFile(output + '.cjs', `module.exports = require('jiti')(null, { interopDefault: true })('${entry.input}')`)
+        await writeFile(output + '.cjs', `${shebang}module.exports = require('jiti')(null, { interopDefault: true })('${entry.input}')`)
       }
-      await writeFile(output + '.mjs', `import jiti from 'jiti';\nexport default jiti(null, { interopDefault: true })('${entry.input}');`)
+      await writeFile(output + '.mjs', `${shebang}import jiti from 'jiti';\nexport default jiti(null, { interopDefault: true })('${entry.input}');`)
       await writeFile(output + '.d.ts', `export * from '${entry.input}';\nexport { default } from '${entry.input}';`)
+
+      if (shebang) {
+        await makeExecutable(output + '.cjs')
+        await makeExecutable(output + '.mjs')
+      }
     }
     await ctx.hooks.callHook('rollup:done', ctx)
     return
@@ -61,6 +73,9 @@ export async function rollupBuild (ctx: BuildContext) {
   // Types
   if (ctx.options.declaration) {
     rollupOptions.plugins = rollupOptions.plugins || []
+    // TODO: Use fresh rollup options
+    const shebangPlugin: any = rollupOptions.plugins.find(p => p && p.name === 'unbuild-shebang')
+    shebangPlugin._options.preserve = false
     rollupOptions.plugins.push(dts({ respectExternal: true }))
     await ctx.hooks.callHook('rollup:dts:options', ctx, rollupOptions)
     const typesBuild = await rollup(rollupOptions)
@@ -143,6 +158,8 @@ export function getRollupOptions (ctx: BuildContext): RollupOptions {
         preferConst: true
       }),
 
+      shebangPlugin(),
+
       esbuild({
         target: 'es2020'
       }),
@@ -158,6 +175,7 @@ export function getRollupOptions (ctx: BuildContext): RollupOptions {
       ctx.options.rollup.cjsBridge && cjsPlugin({}),
 
       rawPlugin()
+
     ].filter(Boolean)
   } as RollupOptions
 }

src/cli.ts

@@ -1,3 +1,4 @@
+#!/bin/env node
 import { resolve } from 'pathe'
 import mri from 'mri'
 import { build } from './build'

src/utils.ts

@@ -44,3 +44,15 @@ export function tryRequire (id: string, rootDir: string = process.cwd()) {
     return {}
   }
 }
+
+export function tryResolve (id: string, rootDir: string = process.cwd()) {
+  const _require = jiti(rootDir, { interopDefault: true })
+  try {
+    return _require.resolve(id)
+  } catch (err: any) {
+    if (err.code !== 'MODULE_NOT_FOUND') {
+      console.error(`Error trying import ${id} from ${rootDir}`, err)
+    }
+    return id
+  }
+}