From d17be5750c8e536547ddefe9a0d24be4fd419898 Mon Sep 17 00:00:00 2001
From: Julien Ripouteau <julien@ripouteau.com>
Date: Wed, 21 Jan 2026 13:12:02 +0100
Subject: [PATCH 1/2] fix: keep import attribute

---
 src/get_config.ts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/get_config.ts b/src/get_config.ts
index 08899a1..778fef0 100644
--- a/src/get_config.ts
+++ b/src/get_config.ts
@@ -36,6 +36,9 @@ const DEFAULT_CONFIG: SWCConfig = {
         runtime: 'automatic',
       },
     },
+    experimental: {
+      keepImportAttributes: true,
+    },
     keepClassNames: true,
   },
 }
@@ -96,6 +99,9 @@ function tsConfigToSwcConfig(tsConfig: TsConfigJsonResolved): SWCConfig {
             : {}),
         },
       },
+      experimental: {
+        keepImportAttributes: true,
+      },
       keepClassNames: true,
     },
   }

From 78fe3fc463f7a1ad7c2b7c5b4909179e7d01f524 Mon Sep 17 00:00:00 2001
From: Julien Ripouteau <julien@ripouteau.com>
Date: Wed, 21 Jan 2026 14:38:59 +0100
Subject: [PATCH 2/2] test: update tests + add new for import attributes

---
 tests/get_config.spec.ts | 12 +++++++++
 tests/loader.spec.ts     | 56 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+)

diff --git a/tests/get_config.spec.ts b/tests/get_config.spec.ts
index 229979e..7a17ab0 100644
--- a/tests/get_config.spec.ts
+++ b/tests/get_config.spec.ts
@@ -16,6 +16,9 @@ test.group('Get config', () => {
       {
         "swcConfig": {
           "jsc": {
+            "experimental": {
+              "keepImportAttributes": true,
+            },
             "externalHelpers": false,
             "keepClassNames": true,
             "parser": {
@@ -59,6 +62,9 @@ test.group('Get config', () => {
         "swcConfig": {
           "jsc": {
             "baseUrl": undefined,
+            "experimental": {
+              "keepImportAttributes": true,
+            },
             "externalHelpers": false,
             "keepClassNames": true,
             "parser": {
@@ -107,6 +113,9 @@ test.group('Get config', () => {
         "swcConfig": {
           "jsc": {
             "baseUrl": undefined,
+            "experimental": {
+              "keepImportAttributes": true,
+            },
             "externalHelpers": false,
             "keepClassNames": true,
             "parser": {
@@ -158,6 +167,9 @@ test.group('Get config', () => {
         "swcConfig": {
           "jsc": {
             "baseUrl": undefined,
+            "experimental": {
+              "keepImportAttributes": true,
+            },
             "externalHelpers": false,
             "keepClassNames": true,
             "parser": {
diff --git a/tests/loader.spec.ts b/tests/loader.spec.ts
index 2816ce5..7f5e5f1 100644
--- a/tests/loader.spec.ts
+++ b/tests/loader.spec.ts
@@ -651,4 +651,60 @@ test.group('Loader', (group) => {
       'Error: Cannot import "./get_path.ts?v=1" using ".ts" extension. Enable "compilerOptions.rewriteRelativeImportExtensions" to import TypeScript files'
     )
   })
+
+  test('preserve import attributes for JSON imports', async ({ assert, fs }) => {
+    await fs.createJson('tsconfig.json', {
+      compilerOptions: {},
+    })
+
+    await fs.createJson('data.json', {
+      name: 'ts-exec',
+      version: '1.0.0',
+    })
+
+    await fs.create(
+      'index.ts',
+      `
+      import data from './data.json' with { type: 'json' }
+      console.log(data.name)
+    `
+    )
+
+    const result = await spawnPromisified(
+      process.execPath,
+      ['--no-warnings', '--import', './build/index.js', join(fs.basePath, 'index.ts')],
+      {}
+    )
+
+    assert.equal(result.stdout.trim(), 'ts-exec')
+    assert.equal(result.stderr.trim(), '')
+  })
+
+  test('preserve import attributes for dynamic JSON imports', async ({ assert, fs }) => {
+    await fs.createJson('tsconfig.json', {
+      compilerOptions: {},
+    })
+
+    await fs.createJson('config.json', {
+      enabled: true,
+      timeout: 5000,
+    })
+
+    await fs.create(
+      'index.ts',
+      `
+      const config = await import('./config.json', { with: { type: 'json' } })
+      console.log(config.default.timeout)
+    `
+    )
+
+    const result = await spawnPromisified(
+      process.execPath,
+      ['--no-warnings', '--import', './build/index.js', join(fs.basePath, 'index.ts')],
+      {}
+    )
+
+    assert.equal(result.stdout.trim(), '5000')
+    assert.equal(result.stderr.trim(), '')
+  })
 })