From 8e288039a871b56803a7a5b66cc3766b6c2267db Mon Sep 17 00:00:00 2001
From: Evan You <yyx990803@gmail.com>
Date: Thu, 28 Jan 2021 11:05:04 -0500
Subject: [PATCH] fix: hold missing dep requests while re-bundling

---
 .../src/node/optimizer/registerMissing.ts     | 28 +++++++++----------
 packages/vite/src/node/plugins/resolve.ts     |  4 ++-
 .../src/node/server/middlewares/transform.ts  |  9 +++++-
 3 files changed, 25 insertions(+), 16 deletions(-)

diff --git a/packages/vite/src/node/optimizer/registerMissing.ts b/packages/vite/src/node/optimizer/registerMissing.ts
index 16db330942158e..86b8fe635e112e 100644
--- a/packages/vite/src/node/optimizer/registerMissing.ts
+++ b/packages/vite/src/node/optimizer/registerMissing.ts
@@ -44,20 +44,6 @@ export function createMissingImpoterRegisterFn(server: ViteDevServer) {
         newDeps
       ))
       knownOptimized = newData!.optimized
-
-      // Importers' cached transform results have stale imports (resolved to
-      // old locations) so they need to be invalidated before the page is
-      // reloaded.
-      currentImporters.forEach((importer) => {
-        const mod = server.moduleGraph.getModuleById(importer)
-        if (mod) server.moduleGraph.invalidateModule(mod)
-      })
-      currentImporters.clear()
-
-      server.ws.send({
-        type: 'full-reload',
-        path: '*'
-      })
     } catch (e) {
       logger.error(
         chalk.red(`error while updating dependencies:\n${e.stack}`),
@@ -71,6 +57,20 @@ export function createMissingImpoterRegisterFn(server: ViteDevServer) {
     logger.info(chalk.greenBright(`✨ dependencies updated.`), {
       timestamp: true
     })
+
+    // Importers' cached transform results have stale imports (resolved to
+    // old locations) so they need to be invalidated before the page is
+    // reloaded.
+    currentImporters.forEach((importer) => {
+      const mod = server.moduleGraph.getModuleById(importer)
+      if (mod) server.moduleGraph.invalidateModule(mod)
+    })
+    currentImporters.clear()
+
+    server.ws.send({
+      type: 'full-reload',
+      path: '*'
+    })
   }
 
   return function registerMissingImport(
diff --git a/packages/vite/src/node/plugins/resolve.ts b/packages/vite/src/node/plugins/resolve.ts
index 97da826c0281f8..ab1f34523edfc2 100644
--- a/packages/vite/src/node/plugins/resolve.ts
+++ b/packages/vite/src/node/plugins/resolve.ts
@@ -45,6 +45,7 @@ function resolveExports(
 // special id for paths marked with browser: false
 // https://github.com/defunctzombie/package-browser-field-spec#ignore-a-module
 export const browserExternalId = '__vite-browser-external'
+export const pendingDepId = '__vite-pending-dep'
 
 const isDebug = process.env.DEBUG
 const debug = createDebugger('vite:resolve-details', {
@@ -365,12 +366,13 @@ export function tryNodeResolve(
       if (versionHash) {
         resolved = injectQuery(resolved, `v=${versionHash}`)
       }
+      return { id: resolved }
     } else {
       // this is a missing import.
       // queue optimize-deps re-run.
       server._registerMissingImport?.(id, resolved, importer)
+      return { id: pendingDepId }
     }
-    return { id: resolved }
   }
 }
 
diff --git a/packages/vite/src/node/server/middlewares/transform.ts b/packages/vite/src/node/server/middlewares/transform.ts
index fb2f13f193bf68..336a21b74f7618 100644
--- a/packages/vite/src/node/server/middlewares/transform.ts
+++ b/packages/vite/src/node/server/middlewares/transform.ts
@@ -1,6 +1,5 @@
 import { ViteDevServer } from '..'
 import { Connect } from 'types/connect'
-import { isCSSRequest, isDirectCSSRequest } from '../../plugins/css'
 import {
   cleanUrl,
   createDebugger,
@@ -21,6 +20,8 @@ import {
   NULL_BYTE_PLACEHOLDER,
   VALID_ID_PREFIX
 } from '../../constants'
+import { pendingDepId } from '../../plugins/resolve'
+import { isCSSRequest, isDirectCSSRequest } from '../../plugins/css'
 
 const debugCache = createDebugger('vite:cache')
 const isDebug = !!process.env.DEBUG
@@ -44,6 +45,12 @@ export function transformMiddleware(
       return next()
     }
 
+    if (server._pendingReload && req.url!.endsWith(pendingDepId)) {
+      // missing dep pending reload, hold request
+      server._pendingReload.then(() => res.end())
+      return
+    }
+
     let url = decodeURI(removeTimestampQuery(req.url!)).replace(
       NULL_BYTE_PLACEHOLDER,
       '\0'