feat(ssr): hook into require during development

This ensures `resolve.dedupe` is respected even by modules not passed through `ssrLoadModule`
vitejs · Jun 27, 2021 · 44afbf6 · 44afbf6
1 parent bdb5750
commit 44afbf6
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Showing 2 changed files with 59 additions and 15 deletions.
diff --git a/packages/vite/src/node/plugins/ssrRequireHook.ts b/packages/vite/src/node/plugins/ssrRequireHook.ts
@@ -2,23 +2,53 @@ import MagicString from 'magic-string'
 import { ResolvedConfig } from '..'
 import { Plugin } from '../plugin'
 
-const impl = `;(function() {
-  const Module = require("module")
+type NodeResolveFilename = (
+  request: string,
+  parent: NodeModule,
+  isMain: boolean,
+  options?: Record<string, any>
+) => string
+
+export function dedupeRequire(dedupe: string[], module: NodeModule) {
+  const Module = require('module') as { _resolveFilename: NodeResolveFilename }
   const resolveFilename = Module._resolveFilename
-  const dedupe = DEDUPE_IDS
-  Module._resolveFilename = function (request, parent, isMain, options) {
-    if (request[0] !== "." && request[0] !== "/") {
-      const parts = request.split("/")
-      const pkgName = parts[0][0] === "@" ? parts[0] + "/" + parts[1] : parts[0]
-      if (dedupe.includes(pkgName)) {
-        // Use this module as the parent.
-        parent = module
+  Module._resolveFilename = getDedupeRequire(resolveFilename)(dedupe, module)
+  return () => {
+    Module._resolveFilename = resolveFilename
+  }
+}
+
+const getDedupeRequire = (resolveFilename?: NodeResolveFilename) => {
+  const dedupeRequireImpl = (
+    dedupe: string[],
+    module: NodeModule
+  ): NodeResolveFilename =>
+    function (request, parent, isMain, options) {
+      if (request[0] !== '.' && request[0] !== '/') {
+        const parts = request.split('/')
+        const pkgName =
+          parts[0][0] === '@' ? parts[0] + '/' + parts[1] : parts[0]
+        if (dedupe.includes(pkgName)) {
+          // Use this module as the parent.
+          parent = module
+        }
       }
+      return resolveFilename!(request, parent, isMain, options)
     }
-    return resolveFilename(request, parent, isMain, options)
+
+  if (resolveFilename) {
+    return dedupeRequireImpl
   }
-})();
-`
+
+  return new Function(
+    `dedupe`,
+    `var Module = require("module");
+var resolveFilename = Module._resolveFilename;
+Module._resolveFilename = ${dedupeRequireImpl
+      .toString()
+      .replace(/^.+? => /, '')};`
+  )
+}
 
 export function ssrRequireHookPlugin(config: ResolvedConfig): Plugin | null {
   if (config.command !== 'build' || !config.resolve.dedupe?.length) {
@@ -31,7 +61,9 @@ export function ssrRequireHookPlugin(config: ResolvedConfig): Plugin | null {
       if (moduleInfo?.isEntry) {
         const s = new MagicString(code)
         s.prepend(
-          impl.replace('DEDUPE_IDS', JSON.stringify(config.resolve.dedupe))
+          `;(${getDedupeRequire()})(${JSON.stringify(
+            config.resolve.dedupe
+          )});\n`
         )
         return {
           code: s.toString(),

diff --git a/packages/vite/src/node/ssr/ssrModuleLoader.ts b/packages/vite/src/node/ssr/ssrModuleLoader.ts
@@ -11,6 +11,7 @@ import {
 } from './ssrTransform'
 import { transformRequest } from '../server/transformRequest'
 import { InternalResolveOptions, tryNodeResolve } from '../plugins/resolve'
+import { dedupeRequire } from '../plugins/ssrRequireHook'
 
 interface SSRContext {
   global: NodeJS.Global
@@ -181,8 +182,19 @@ function nodeRequire(
   if (!resolved) {
     throw Error(`Cannot find module '${id}'`)
   }
-  const mod = require(resolved.id)
+
+  const unhookRequire = resolveOptions.dedupe?.length
+    ? dedupeRequire(resolveOptions.dedupe, module)
+    : null
+
+  try {
+    var mod = require(resolved.id)
+  } finally {
+    unhookRequire?.()
+  }
+
   const defaultExport = mod.__esModule ? mod.default : mod
+
   // rollup-style default import interop for cjs
   return new Proxy(mod, {
     get(mod, prop) {