test(resolve): add test case for #20972 (#20975)

Author: Copilot

playground/resolve/__tests__/resolve.spec.ts

@@ -228,6 +228,10 @@ test('Resolving with query with imports field', async () => {
   )
 })
 
+test('Resolving dot-prefixed directory with imports field', async () => {
+  expect(await page.textContent('.imports-dot-prefixed')).toMatch('[success]')
+})
+
 test("Resolve doesn't interrupt page request with trailing query and .css", async () => {
   await page.goto(viteTestUrl + '/?test.css')
   expect(await page.locator('vite-error-overlay').count()).toBe(0)

playground/resolve/imports-path/.dot-prefixed/index.js

@@ -0,0 +1 @@
+export const msg = '[success] dot-prefixed subpath imports'

playground/resolve/imports-path/importer.js

@@ -0,0 +1,3 @@
+import { msg } from '#dot-prefixed'
+
+export { msg }

playground/resolve/index.html

@@ -64,6 +64,9 @@ <h2>Resolving from other package with imports field</h2>
 <h2>Resolving with query with imports field</h2>
 <p class="imports-query">fail</p>
 
+<h2>Resolving dot-prefixed directory with imports field</h2>
+<p class="imports-dot-prefixed">fail</p>
+
 <h2>Resolve /index.*</h2>
 <p class="index">fail</p>
 
@@ -272,6 +275,9 @@ <h2>utf8-bom-package</h2>
   import importsQuery from '#query?url'
   text('.imports-query', importsQuery)
 
+  import { msg as importsDotPrefixed } from './imports-path/importer.js'
+  text('.imports-dot-prefixed', importsDotPrefixed)
+
   // implicit index resolving
   import { foo } from './util'
   text('.index', foo())

playground/resolve/package.json

@@ -16,7 +16,8 @@
     "#star/*": "./imports-path/star/*",
     "#slash/": "./imports-path/slash/",
     "#other-pkg-slash/": "@vitejs/test-resolve-imports-pkg/nest/",
-    "#query": "./imports-path/query.json"
+    "#query": "./imports-path/query.json",
+    "#dot-prefixed": "./imports-path/.dot-prefixed/index.js"
   },
   "dependencies": {
     "@babel/runtime": "^7.28.4",