fix(resolve): fix resolver not following node resolve algorithm (#2718)…

…, fix #2695

packages/playground/resolve/__tests__/resolve.spec.ts

@@ -42,6 +42,14 @@ test('implicit dir/index.js vs explicit file', async () => {
   expect(await page.textContent('.dir-vs-file')).toMatch('[success]')
 })
 
+test('exact extension vs. duplicated (.js.js)', async () => {
+  expect(await page.textContent('.exact-extension')).toMatch('[success]')
+})
+
+test('dont add extension to directory name (./dir-with-ext.js/index.js)', async () => {
+  expect(await page.textContent('.dir-with-ext')).toMatch('[success]')
+})
+
 test('filename with dot', async () => {
   expect(await page.textContent('.dot')).toMatch('[success]')
 })

packages/playground/resolve/dir-with-ext/index.js

@@ -0,0 +1 @@
+export const file = '[success] ./dir-with-ext/index.js'

packages/playground/resolve/exact-extension/file.js

@@ -0,0 +1 @@
+export const file = '[success] file.js'

packages/playground/resolve/exact-extension/file.js.js

@@ -0,0 +1 @@
+export const file = 'file.js.js'

packages/playground/resolve/index.html

@@ -24,6 +24,12 @@ <h2>Resolve /index.*</h2>
 <h2>Resolve dir and file of the same name (should prioritize file)</h2>
 <p class="dir-vs-file">fail</p>
 
+<h2>Resolve to non-duplicated file extension</h2>
+<p class="exact-extension">fail</p>
+
+<h2>Don't add extensions to directory names</h2>
+<p class="dir-with-ext">fail</p>
+
 <h2>Resolve file name containing dot</h2>
 <p class="dot">fail</p>
 
@@ -95,6 +101,14 @@ <h2>resolve.conditions</h2>
   import { file } from './dir'
   text('.dir-vs-file', file)
 
+  // // exact extension vs. duplicated (.js.js)
+  import { file as exactExtMsg } from './exact-extension/file.js'
+  text('.exact-extension', exactExtMsg)
+
+  // don't add extensions to dir name (./dir-with-ext.js/index.js)
+  import { file as dirWithExtMsg } from './dir-with-ext'
+  text('.dir-with-ext', dirWithExtMsg)
+
   // filename with dot
   import { bar } from './util/bar.util'
   text('.dot', bar())

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

@@ -240,6 +240,12 @@ function tryFsResolve(
   }
 
   let res: string | undefined
+  if (
+    (res = tryResolveFile(file, postfix, options, false, options.tryPrefix))
+  ) {
+    return res
+  }
+
   for (const ext of options.extensions || DEFAULT_EXTENSIONS) {
     if (
       (res = tryResolveFile(
@@ -288,8 +294,6 @@ function tryResolveFile(
       }
       const index = tryFsResolve(file + '/index', options)
       if (index) return index + postfix
-    } else {
-      return normalizePath(ensureVolumeInPath(file)) + postfix
     }
   }
   if (tryPrefix) {