fix(build): fix resolution algorithm when build.ssr is true

packages/vite/src/node/plugins/resolve.ts

@@ -717,7 +717,11 @@ export function tryNodeResolve(
     let resolvedId = id
     if (isDeepImport) {
       if (!pkg?.data.exports && path.extname(id) !== resolvedExt) {
-        resolvedId += resolvedExt
+        resolvedId = resolved.id.slice(resolved.id.indexOf(id))
+        isDebug &&
+          debug(
+            `[processResult] ${colors.cyan(id)} -> ${colors.dim(resolvedId)}`
+          )
       }
     }
     return { ...resolved, id: resolvedId, external: true }

playground/ssr-resolve/__tests__/ssr-resolve.spec.ts

@@ -0,0 +1,13 @@
+import { expect, test } from 'vitest'
+import { isBuild, readFile, testDir } from '~utils'
+
+test.runIf(isBuild)('correctly resolve entrypoints', async () => {
+  const contents = readFile('dist/main.mjs')
+
+  const _ = `['"]`
+  expect(contents).toMatch(new RegExp(`from ${_}entries/dir/index.js${_}`))
+  expect(contents).toMatch(new RegExp(`from ${_}entries/file.js${_}`))
+  expect(contents).toMatch(new RegExp(`from ${_}pkg-exports/entry${_}`))
+
+  await expect(import(`${testDir}/dist/main.mjs`)).resolves.toBeTruthy()
+})

playground/ssr-resolve/entries/dir/index.js

@@ -0,0 +1 @@
+module.exports = __filename.slice(__filename.lastIndexOf('entries'))

playground/ssr-resolve/entries/file.js

@@ -0,0 +1 @@
+module.exports = __filename.slice(__filename.lastIndexOf('entries'))

playground/ssr-resolve/entries/package.json

@@ -0,0 +1,5 @@
+{
+  "name": "entries",
+  "private": true,
+  "version": "0.0.0"
+}

playground/ssr-resolve/main.js

@@ -0,0 +1,12 @@
+// no `exports` key, should resolve to entries/dir/index.js
+import dirEntry from 'entries/dir'
+// no `exports` key, should resolve to entries/file.js
+import fileEntry from 'entries/file'
+// has `exports` key, should resolve to pkg-exports/entry
+import pkgExportsEntry from 'pkg-exports/entry'
+
+export default `
+  entries/dir: ${dirEntry}
+  entries/file: ${fileEntry}
+  pkg-exports/entry: ${pkgExportsEntry}
+`

playground/ssr-resolve/package.json

@@ -0,0 +1,13 @@
+{
+  "name": "ssr-resolve",
+  "private": true,
+  "version": "0.0.0",
+  "scripts": {
+    "build": "vite build",
+    "debug": "node --inspect-brk ../../packages/vite/bin/vite build"
+  },
+  "dependencies": {
+    "entries": "file:./entries",
+    "pkg-exports": "file:./pkg-exports"
+  }
+}

playground/ssr-resolve/pkg-exports/entry.js

@@ -0,0 +1 @@
+module.exports = 'pkg-exports entry'

playground/ssr-resolve/pkg-exports/index.js

@@ -0,0 +1 @@
+module.exports = undefined

playground/ssr-resolve/pkg-exports/package.json

@@ -0,0 +1,9 @@
+{
+  "name": "pkg-exports",
+  "private": true,
+  "version": "0.0.0",
+  "exports": {
+    ".": "./index.js",
+    "./entry": "./entry.js"
+  }
+}

playground/ssr-resolve/vite.config.js

@@ -0,0 +1,8 @@
+import { resolve } from 'node:path'
+import { defineConfig } from 'vite'
+
+export default defineConfig({
+  build: {
+    ssr: './main.js'
+  }
+})