fix: error on missing file (#83)

privatenumber · web-flow · commit 320f20f29106 · 2025-08-14T06:23:43.000+08:00
diff --git a/src/resolver.ts b/src/resolver.ts
@@ -73,11 +73,19 @@ export function createDtsResolvePlugin({
           !dtsResolution ||
           (!RE_TS.test(dtsResolution) && !RE_VUE.test(dtsResolution))
         ) {
-          if (
+          const unresolved =
             !rolldownResolution ||
             (!RE_TS.test(rolldownResolution.id) &&
               !RE_VUE.test(rolldownResolution.id))
-          ) {
+
+          if (unresolved) {
+            // For relative/absolute type imports, surface an error instead of
+            // silently externalizing so users know a local type file is missing.
+            const isRelativeOrAbsolute =
+              id.startsWith('.') || path.isAbsolute(id)
+            if (isRelativeOrAbsolute) {
+              return this.error(`Cannot resolve import '${id}' from '${importer}'`)
+            }
             return external
           }
           dtsResolution = rolldownResolution.id
diff --git a/tests/fixtures/unresolved-import/index.d.ts b/tests/fixtures/unresolved-import/index.d.ts
@@ -0,0 +1 @@
+export * from './missing-file'
diff --git a/tests/index.test.ts b/tests/index.test.ts
@@ -164,3 +164,16 @@ test('cjs exports', async () => {
     expect(snapshot).toMatchSnapshot()
   }
 })
+
+test('should error when file import cannot be found', async () => {
+  await expect(() =>
+    rolldownBuild(
+      path.resolve(dirname, 'fixtures/unresolved-import/index.d.ts'),
+      [
+        dts({
+          emitDtsOnly: true,
+        }),
+      ],
+    ),
+  ).rejects.toThrow("Cannot resolve import './missing-file'")
+})
