From a5262e4fa998d4fe4a733ac656c23fe198b72589 Mon Sep 17 00:00:00 2001
From: Pooya Parsa <pyapar@gmail.com>
Date: Tue, 15 Mar 2022 18:39:39 +0100
Subject: [PATCH] fix: improve externals handling

---
 src/rollup/plugins/externals.ts | 67 ++++++++++++++++++++++-----------
 1 file changed, 46 insertions(+), 21 deletions(-)

diff --git a/src/rollup/plugins/externals.ts b/src/rollup/plugins/externals.ts
index 02c8450ea8..68beb7cc40 100644
--- a/src/rollup/plugins/externals.ts
+++ b/src/rollup/plugins/externals.ts
@@ -2,14 +2,13 @@ import { existsSync, promises as fsp } from 'fs'
 import { resolve, dirname, normalize } from 'pathe'
 import { nodeFileTrace, NodeFileTraceOptions } from '@vercel/nft'
 import type { Plugin } from 'rollup'
-import { resolvePath, isValidNodeImport, normalizeid } from 'mlly'
+import { resolvePath, isValidNodeImport } from 'mlly'
 
 export interface NodeExternalsOptions {
   inline?: string[]
   external?: string[]
   outDir?: string
   trace?: boolean
-  normalizeId?: boolean
   traceOptions?: NodeFileTraceOptions
   moduleDirectories?: string[]
   exportConditions?: string[]
@@ -21,26 +20,32 @@ export function externals (opts: NodeExternalsOptions): Plugin {
 
   return {
     name: 'node-externals',
-    async resolveId (id, importer, options) {
+    async resolveId (originalId, importer, options) {
       // Skip internals
-      if (!id || id.startsWith('\x00') || id.includes('?') || id.startsWith('#')) {
+      if (!originalId || originalId.startsWith('\x00') || originalId.includes('?') || originalId.startsWith('#')) {
         return null
       }
 
-      // Normalize path on windows
-      const normalizedId = normalize(id)
+      // Skip relative paths
+      if (originalId.startsWith('.')) {
+        return null
+      }
 
-      const _id = normalizedId.split('node_modules/').pop()
-      if (!opts.external.find(i => _id.startsWith(i) || id.startsWith(i))) {
-        // Resolve relative paths and exceptions
-        // Ensure to take absolute and relative id
-        if (_id.startsWith('.') || opts.inline.find(i => _id.startsWith(i) || normalizedId.startsWith(i))) {
-          return null
-        }
+      // Normalize path (windows)
+      const id = normalize(originalId)
+
+      // Id without .../node_modules/
+      const idWithoutNodeModules = id.split('node_modules/').pop()
+
+      // const matchedExternal = opts.external.find(i => idWithoutNodeModules.startsWith(i) || id.startsWith(i))
+
+      // Check for explicit inlines
+      if (opts.inline.find(i => (id.startsWith(i) || idWithoutNodeModules.startsWith(i)))) {
+        return null
       }
 
-      // Resolve external (rollup => node)
-      const resolved = await this.resolve(id, importer, { ...options, skipSelf: true }) || { id }
+      // Resolve id (rollup then native node ESM)
+      const resolved = await this.resolve(originalId, importer, { ...options, skipSelf: true }) || { id }
       if (!existsSync(resolved.id)) {
         resolved.id = await resolvePath(resolved.id, {
           conditions: opts.exportConditions,
@@ -48,7 +53,7 @@ export function externals (opts: NodeExternalsOptions): Plugin {
         })
       }
 
-      // Ensure id is a valid import
+      // Inline invalid node imports
       if (!await isValidNodeImport(resolved.id)) {
         return {
           ...resolved,
@@ -59,11 +64,23 @@ export function externals (opts: NodeExternalsOptions): Plugin {
       // Track externals
       trackedExternals.add(resolved.id)
 
-      // Normalize id with explicit protocol
-      if (opts.normalizeId) {
-        resolved.id = normalizeid(resolved.id)
+      // Try to extract package name from path
+      const { pkgName } = parseNodeModulePath(resolved.id)
+
+      // Inline in trace-mode when cannot extract package name
+      if (!pkgName && opts.trace !== false) {
+        return null
+      }
+
+      // External with package name in trace mode
+      if (opts.trace !== false) {
+        return {
+          id: pkgName,
+          external: true
+        }
       }
 
+      // External with full pack in normal mode
       return {
         ...resolved,
         external: true
@@ -81,10 +98,10 @@ export function externals (opts: NodeExternalsOptions): Plugin {
           .then(r => Array.from(r.fileList).map(f => resolve(opts.traceOptions.base, f)))
           .then(r => r.filter(file => file.includes('node_modules')))
 
-        // // Find all unique package names
+        // Find all unique package names
         const pkgs = new Set<string>()
         for (const file of tracedFiles) {
-          const [, baseDir, pkgName] = /^(.+\/node_modules\/)([^@/]+|@[^/]+\/[^/]+)(\/?.*?)?$/.exec(file)
+          const { baseDir, pkgName } = parseNodeModulePath(file)
           pkgs.add(resolve(baseDir, pkgName, 'package.json'))
         }
 
@@ -114,6 +131,14 @@ export function externals (opts: NodeExternalsOptions): Plugin {
   }
 }
 
+function parseNodeModulePath (path: string) {
+  const [, baseDir, pkgName] = /^(.+\/node_modules\/)([^@/]+|@[^/]+\/[^/]+)(\/?.*?)?$/.exec(path)
+  return {
+    baseDir,
+    pkgName
+  }
+}
+
 async function isFile (file: string) {
   try {
     const stat = await fsp.stat(file)