Fix a relative ordering issue where a configuration could override a with attribute and add a test

Author: lukesandberg

test/e2e/turbopack-import-with-type/app/api/configured-as-ecmascript.txt

@@ -0,0 +1 @@
+throw new Error('this file is configured as ecmascript but imported as bytes')

test/e2e/turbopack-import-with-type/app/api/route.js

@@ -2,6 +2,7 @@ import text from './data.txt' with { type: 'text' }
 import jsAsText from './some.js' with { type: 'text' }
 import bytes from './data.bin' with { type: 'bytes' }
 import jsAsBytes from './some.js' with { type: 'bytes' }
+import configuredAsJsAsBytes from './configured-as-ecmascript.txt' with { type: 'bytes' }
 
 export async function GET(_req) {
   return Response.json(
@@ -24,6 +25,10 @@ export async function GET(_req) {
         instanceofUint8Array: jsAsBytes instanceof Uint8Array,
         content: new TextDecoder().decode(jsAsBytes),
       },
+      configuredAsJsAsBytes: {
+        instanceofUint8Array: configuredAsJsAsBytes instanceof Uint8Array,
+        content: new TextDecoder().decode(configuredAsJsAsBytes),
+      },
     },
     { status: 200 }
   )

test/e2e/turbopack-import-with-type/index.test.ts

@@ -37,6 +37,11 @@ describe('turbopack-import-with-type', () => {
         instanceofUint8Array: true,
         content: jsContent,
       },
+      configuredAsJsAsBytes: {
+        instanceofUint8Array: true,
+        content:
+          "throw new Error('this file is configured as ecmascript but imported as bytes')\n",
+      },
     })
   })
 })

test/e2e/turbopack-import-with-type/next.config.ts

@@ -1,6 +1,19 @@
-export default {
+import type { NextConfig } from 'next'
+
+const config: NextConfig = {
   experimental: {
     turbopackImportTypeBytes: true,
     turbopackImportTypeText: true,
   },
+  turbopack: {
+    rules: {
+      // This rule configures a .txt file as ecmascript to test that
+      // import attributes (with { type: 'bytes' }) take priority
+      '**/configured-as-ecmascript.txt': {
+        type: 'ecmascript',
+      },
+    },
+  },
 }
+
+export default config

turbopack/crates/turbopack/src/module_options/mod.rs

@@ -361,6 +361,31 @@ impl ModuleOptions {
 
         let mut rules = vec![];
 
+        // Import attribute rules (bytes/text) must come BEFORE config rules.
+        // Import attributes have a stronger API contract - they're explicit in the source code
+        // and should override any file-pattern-based config rules.
+        if enable_import_as_bytes {
+            rules.push(ModuleRule::new(
+                RuleCondition::ReferenceType(ReferenceType::EcmaScriptModules(
+                    EcmaScriptModulesReferenceSubType::ImportWithType("bytes".into()),
+                )),
+                vec![ModuleRuleEffect::SourceTransforms(ResolvedVc::cell(vec![
+                    ResolvedVc::upcast(BytesSourceTransform::new().to_resolved().await?),
+                ]))],
+            ));
+        }
+
+        if enable_import_as_text {
+            rules.push(ModuleRule::new(
+                RuleCondition::ReferenceType(ReferenceType::EcmaScriptModules(
+                    EcmaScriptModulesReferenceSubType::ImportWithType("text".into()),
+                )),
+                vec![ModuleRuleEffect::SourceTransforms(ResolvedVc::cell(vec![
+                    ResolvedVc::upcast(TextSourceTransform::new().to_resolved().await?),
+                ]))],
+            ));
+        }
+
         if let Some(webpack_loaders_options) = enable_webpack_loaders {
             let webpack_loaders_options = webpack_loaders_options.await?;
             let execution_context =
@@ -531,34 +556,6 @@ impl ModuleOptions {
             ),
         ]);
 
-        if enable_import_as_bytes {
-            // Rule to apply the source transform when importing with type:"bytes".
-            // The transform renames the file to .mjs, so the existing .mjs rule will
-            // set the module type to Ecmascript.
-            rules.push(ModuleRule::new(
-                RuleCondition::ReferenceType(ReferenceType::EcmaScriptModules(
-                    EcmaScriptModulesReferenceSubType::ImportWithType("bytes".into()),
-                )),
-                vec![ModuleRuleEffect::SourceTransforms(ResolvedVc::cell(vec![
-                    ResolvedVc::upcast(BytesSourceTransform::new().to_resolved().await?),
-                ]))],
-            ));
-        }
-
-        if enable_import_as_text {
-            // Rule to apply the source transform when importing with type:"text".
-            // The transform renames the file to .mjs, so the existing .mjs rule will
-            // set the module type to Ecmascript.
-            rules.push(ModuleRule::new(
-                RuleCondition::ReferenceType(ReferenceType::EcmaScriptModules(
-                    EcmaScriptModulesReferenceSubType::ImportWithType("text".into()),
-                )),
-                vec![ModuleRuleEffect::SourceTransforms(ResolvedVc::cell(vec![
-                    ResolvedVc::upcast(TextSourceTransform::new().to_resolved().await?),
-                ]))],
-            ));
-        }
-
         // Rules that apply based on file extension or content type
         rules.extend([
             ModuleRule::new_all(