fix: stack overflow when config have both default and named exports (#49)

Author: astrochemx

packages/unconfig/src/interop.ts

@@ -9,15 +9,16 @@ export function interopDefault<T>(mod: T & { default?: T }): T {
 
   for (const key in mod) {
     try {
-      if (!(key in defaultValue)) {
-        Object.defineProperty(defaultValue, key, {
-          enumerable: key !== 'default',
-          configurable: key !== 'default',
-          get() {
-            return (mod as any)[key]
-          },
-        })
-      }
+      if (key in defaultValue || key === 'default' || (mod as any)[key] === defaultValue)
+        continue
+
+      Object.defineProperty(defaultValue, key, {
+        configurable: true,
+        enumerable: true,
+        get() {
+          return (mod as any)[key]
+        },
+      })
     }
     catch {}
   }

packages/unconfig/test/run.test.ts

@@ -124,6 +124,94 @@ it.each([
   expect(result2.config).toEqual({
     value: 'two',
   })
+
+  // Test config with default and named exports simultaneously
+  await writeFile(configPath, `export const config = {
+  value: 'three',
+}
+export default config`, 'utf8')
+
+  const result3 = await loadConfig({
+    sources: [{ files: configFileName }],
+    cwd,
+  })
+
+  expect(result3.config).toEqual({
+    value: 'three',
+  })
+
+  // Test config with several named exports only
+  await writeFile(configPath, `export const config1 = {
+  value1: 'config-1',
+}
+export const config2= {
+  value2: 'config-2',
+}`, 'utf8')
+
+  const result4 = await loadConfig({
+    sources: [{ files: configFileName }],
+    cwd,
+  })
+
+  expect(result4.config).toEqual({
+    config1: {
+      value1: 'config-1',
+    },
+    config2: {
+      value2: 'config-2',
+    },
+  })
+
+  // Test config with default and several named exports simultaneously
+  await writeFile(configPath, `export const config1 = {
+  value1: 'config-1',
+}
+export const config2= {
+  value2: 'config-2',
+}
+export const config3= {
+  value3: 'config-3',
+}
+export default config3`, 'utf8')
+
+  const result5 = await loadConfig({
+    sources: [{ files: configFileName }],
+    cwd,
+  })
+
+  expect(result5.config).toEqual({
+    config1: {
+      value1: 'config-1',
+    },
+    config2: {
+      value2: 'config-2',
+    },
+    value3: 'config-3',
+  })
+
+  // Test config when default export property and named export itself have similar names
+  await writeFile(configPath, `export const config1 = {
+  value1: 'config-1',
+}
+export const config2= {
+  value2: 'config-2',
+}
+export const config3= {
+  config1: 'config-3',
+}
+export default config3`, 'utf8')
+
+  const result6 = await loadConfig({
+    sources: [{ files: configFileName }],
+    cwd,
+  })
+
+  expect(result6.config).toEqual({
+    config1: 'config-3',
+    config2: {
+      value2: 'config-2',
+    },
+  })
 })
 
 it('custom parser', async () => {