Cleanup Turbopack and error message

Author: mischnic

crates/next-core/src/middleware.rs

@@ -1,7 +1,4 @@
-use std::env;
-
 use anyhow::Result;
-use pathdiff::diff_paths;
 use turbo_rcstr::{RcStr, rcstr};
 use turbo_tasks::{ResolvedVc, Vc, fxindexmap};
 use turbo_tasks_fs::FileSystemPath;
@@ -125,30 +122,6 @@ struct MiddlewareMissingExportIssue {
     file_path: FileSystemPath,
 }
 
-impl MiddlewareMissingExportIssue {
-    fn get_relative_path(&self) -> String {
-        // Get relative path from current working directory (like process.cwd() in JavaScript)
-        let cwd = env::current_dir().ok();
-        let file_path_str = self.file_path.path.as_str();
-        let relative_path = if let Some(cwd) = cwd {
-            diff_paths(file_path_str, cwd)
-                .and_then(|p| p.to_str().map(|s| s.to_string()))
-                .unwrap_or_else(|| self.file_path.file_name().to_string())
-        } else {
-            self.file_path.file_name().to_string()
-        };
-        format!("./{}", relative_path)
-    }
-
-    fn get_type_description(&self) -> &str {
-        if self.file_type.as_str() == "Proxy" {
-            "proxy (previously called middleware)"
-        } else {
-            "middleware"
-        }
-    }
-}
-
 #[turbo_tasks::value_impl]
 impl Issue for MiddlewareMissingExportIssue {
     #[turbo_tasks::function]
@@ -167,24 +140,23 @@ impl Issue for MiddlewareMissingExportIssue {
 
     #[turbo_tasks::function]
     async fn title(&self) -> Result<Vc<StyledString>> {
-        let relative_path_str = self.get_relative_path();
-
-        // Only the first line goes in title to avoid formatIssue indentation
         let title_text = format!(
-            "The file \"{}\" must export a function, either as a default export or as a named \
-             \"{}\" export.",
-            relative_path_str, self.function_name
+            "{} is missing expected function export name",
+            self.file_type
         );
 
         Ok(StyledString::Text(title_text.into()).cell())
     }
 
     #[turbo_tasks::function]
     async fn description(&self) -> Result<Vc<OptionStyledString>> {
-        let relative_path_str = self.get_relative_path();
-        let type_description = self.get_type_description();
+        let type_description = if self.file_type == "Proxy" {
+            "proxy (previously called middleware)"
+        } else {
+            "middleware"
+        };
 
-        let migration_bullet = if self.file_type.as_str() == "Proxy" {
+        let migration_bullet = if self.file_type == "Proxy" {
             "- You are migrating from `middleware` to `proxy`, but haven't updated the exported \
              function.\n"
         } else {
@@ -200,13 +172,11 @@ impl Issue for MiddlewareMissingExportIssue {
              - The export is not a function (e.g., an object or constant).\n\
              - There's a syntax error preventing the export from being recognized.\n\n\
              To fix it:\n\
-             - Check your \"{}\" file.\n\
-             - Ensure it has either a default or \"{}\" function export.\n\
+             - Ensure this file has either a default or \"{}\" function export.\n\
              - Restart the dev server if the error persists.\n\n\
              Learn more: https://nextjs.org/docs/messages/middleware-to-proxy",
             type_description,
             migration_bullet,
-            relative_path_str,
             self.function_name
         );
 

packages/next/errors.json

@@ -897,5 +897,6 @@
   "896": "oops",
   "897": "Expected HTML document to start with doctype prefix",
   "898": "The file \"%s\" must export a function, either as a default export or as a named \"%s\" export.\\nThis function is what Next.js runs for every request handled by this %s.\\n\\nWhy this happens:\\n- The file exists but doesn't export a function.\\n- The export is not a function (e.g., an object or constant).\\n- There's a syntax error preventing the export from being recognized.\\n\\nTo fix it:\\n- Check your \"%s\" file.\\n- Ensure it has either a default or \"%s\" function export.\\n- Restart the dev server if the error persists.\\n\\nLearn more: https://nextjs.org/docs/messages/middleware-to-proxy",
-  "899": "The file \"%s\" must export a function, either as a default export or as a named \"%s\" export.\\nThis function is what Next.js runs for every request handled by this %s.\\n\\nWhy this happens:\\n%s- The file exists but doesn't export a function.\\n- The export is not a function (e.g., an object or constant).\\n- There's a syntax error preventing the export from being recognized.\\n\\nTo fix it:\\n- Check your \"%s\" file.\\n- Ensure it has either a default or \"%s\" function export.\\n- Restart the dev server if the error persists.\\n\\nLearn more: https://nextjs.org/docs/messages/middleware-to-proxy"
+  "899": "The file \"%s\" must export a function, either as a default export or as a named \"%s\" export.\\nThis function is what Next.js runs for every request handled by this %s.\\n\\nWhy this happens:\\n%s- The file exists but doesn't export a function.\\n- The export is not a function (e.g., an object or constant).\\n- There's a syntax error preventing the export from being recognized.\\n\\nTo fix it:\\n- Check your \"%s\" file.\\n- Ensure it has either a default or \"%s\" function export.\\n- Restart the dev server if the error persists.\\n\\nLearn more: https://nextjs.org/docs/messages/middleware-to-proxy",
+  "900": "The file \"%s\" must export a function, either as a default export or as a named \"%s\" export.\\nThis function is what Next.js runs for every request handled by this %s.\\n\\nWhy this happens:\\n%s- The file exists but doesn't export a function.\\n- The export is not a function (e.g., an object or constant).\\n- There's a syntax error preventing the export from being recognized.\\n\\nTo fix it:\\n- Ensure this file has either a default or \"%s\" function export.\\n- Restart the dev server if the error persists.\\n\\nLearn more: https://nextjs.org/docs/messages/middleware-to-proxy"
 }

packages/next/src/build/analysis/get-page-static-info.ts

@@ -410,8 +410,7 @@ function validateMiddlewareProxyExports({
         `- The export is not a function (e.g., an object or constant).\n` +
         `- There's a syntax error preventing the export from being recognized.\n\n` +
         `To fix it:\n` +
-        `- Check your "${relativeFilePath}" file.\n` +
-        `- Ensure it has either a default or "${fileName}" function export.\n` +
+        `- Ensure this file has either a default or "${fileName}" function export.\n` +
         `- Restart the dev server if the error persists.\n\n` +
         `Learn more: https://nextjs.org/docs/messages/middleware-to-proxy`
     )

packages/next/src/build/templates/middleware.ts

@@ -36,8 +36,7 @@ if (typeof handler !== 'function') {
       `- The export is not a function (e.g., an object or constant).\n` +
       `- There's a syntax error preventing the export from being recognized.\n\n` +
       `To fix it:\n` +
-      `- Check your "${resolvedRelativeFilePath}" file.\n` +
-      `- Ensure it has either a default or "${fileName}" function export.\n` +
+      `- Ensure this file has either a default or "${fileName}" function export.\n` +
       `- Restart the dev server if the error persists.\n\n` +
       `Learn more: https://nextjs.org/docs/messages/middleware-to-proxy`
   )

test/e2e/app-dir/proxy-missing-export/proxy-missing-export.test.ts

@@ -2,8 +2,7 @@ import { nextTestSetup } from 'e2e-utils'
 import { join } from 'node:path'
 import { writeFile } from 'node:fs/promises'
 
-const errorMessage = `The file "./proxy.ts" must export a function, either as a default export or as a named "proxy" export.
-This function is what Next.js runs for every request handled by this proxy (previously called middleware).
+const errorMessage = `This function is what Next.js runs for every request handled by this proxy (previously called middleware).
 
 Why this happens:
 - You are migrating from \`middleware\` to \`proxy\`, but haven't updated the exported function.
@@ -12,8 +11,7 @@ Why this happens:
 - There's a syntax error preventing the export from being recognized.
 
 To fix it:
-- Check your "./proxy.ts" file.
-- Ensure it has either a default or "proxy" function export.
+- Ensure this file has either a default or "proxy" function export.
 - Restart the dev server if the error persists.
 
 Learn more: https://nextjs.org/docs/messages/middleware-to-proxy`
@@ -35,14 +33,25 @@ describe('proxy-missing-export', () => {
       'export function middleware() {}'
     )
 
+    let cliOutput: string
+
     if (isNextDev) {
       await next.start().catch(() => {})
       // Use .catch() because Turbopack errors during compile and exits before runtime.
       await next.browser('/').catch(() => {})
-      expect(next.cliOutput).toContain(errorMessage)
+      cliOutput = next.cliOutput
+    } else {
+      cliOutput = (await next.build()).cliOutput
+    }
+
+    if (process.env.IS_TURBOPACK_TEST) {
+      expect(cliOutput).toContain(`./proxy.ts
+Proxy is missing expected function export name
+${errorMessage}`)
     } else {
-      const { cliOutput } = await next.build()
-      expect(cliOutput).toContain(errorMessage)
+      expect(cliOutput)
+        .toContain(`The file "./proxy.ts" must export a function, either as a default export or as a named "proxy" export.
+${errorMessage}`)
     }
 
     await next.stop()
@@ -107,16 +116,26 @@ describe('proxy-missing-export', () => {
       'const proxy = () => {}; export { proxy as handler };'
     )
 
+    let cliOutput: string
+
     if (isNextDev) {
       await next.start().catch(() => {})
       // Use .catch() because Turbopack errors during compile and exits before runtime.
       await next.browser('/').catch(() => {})
-      expect(next.cliOutput).toContain(errorMessage)
+      cliOutput = next.cliOutput
     } else {
-      const { cliOutput } = await next.build()
-      expect(cliOutput).toContain(errorMessage)
+      cliOutput = (await next.build()).cliOutput
     }
 
+    if (process.env.IS_TURBOPACK_TEST) {
+      expect(cliOutput).toContain(`./proxy.ts
+Proxy is missing expected function export name
+${errorMessage}`)
+    } else {
+      expect(cliOutput)
+        .toContain(`The file "./proxy.ts" must export a function, either as a default export or as a named "proxy" export.
+${errorMessage}`)
+    }
     await next.stop()
   })
 })

test/e2e/app-dir/proxy-missing-export/proxy.ts

@@ -0,0 +1 @@
+export function x() {}