From 15ba863914fc041dcdc399df1a79784b0ba8354f Mon Sep 17 00:00:00 2001
From: Chiawen Chen <golopot@gmail.com>
Date: Fri, 18 Oct 2019 18:03:49 +0800
Subject: [PATCH] [Fix] false positive for prefer-default-export with type
 export

---
 src/rules/prefer-default-export.js       | 8 ++++----
 tests/src/rules/prefer-default-export.js | 9 ++++++++-
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/rules/prefer-default-export.js b/src/rules/prefer-default-export.js
index f0af00d02..17a07688c 100644
--- a/src/rules/prefer-default-export.js
+++ b/src/rules/prefer-default-export.js
@@ -14,6 +14,7 @@ module.exports = {
     let specifierExportCount = 0
     let hasDefaultExport = false
     let hasStarExport = false
+    let hasTypeExport = false
     let namedExportNode = null
 
     function captureDeclaration(identifierOrPattern) {
@@ -50,9 +51,6 @@ module.exports = {
         // if there are specifiers, node.declaration should be null
         if (!node.declaration) return
 
-        // don't warn on single type aliases, declarations, or interfaces
-        if (node.exportKind === 'type') return
-
         const { type } = node.declaration
 
         if (
@@ -61,6 +59,8 @@ module.exports = {
           type === 'TSInterfaceDeclaration' ||
           type === 'InterfaceDeclaration'
         ) {
+          specifierExportCount++
+          hasTypeExport = true
           return
         }
 
@@ -86,7 +86,7 @@ module.exports = {
       },
 
       'Program:exit': function() {
-        if (specifierExportCount === 1 && !hasDefaultExport && !hasStarExport) {
+        if (specifierExportCount === 1 && !hasDefaultExport && !hasStarExport && !hasTypeExport) {
           context.report(namedExportNode, 'Prefer default export.')
         }
       },
diff --git a/tests/src/rules/prefer-default-export.js b/tests/src/rules/prefer-default-export.js
index 452192737..19aef41e0 100644
--- a/tests/src/rules/prefer-default-export.js
+++ b/tests/src/rules/prefer-default-export.js
@@ -3,7 +3,7 @@ import { test, getNonDefaultParsers } from '../utils'
 import { RuleTester } from 'eslint'
 
 const ruleTester = new RuleTester()
-    , rule = require('rules/prefer-default-export')
+    , rule = require('../../../src/rules/prefer-default-export')
 
 ruleTester.run('prefer-default-export', rule, {
   valid: [
@@ -194,6 +194,13 @@ context('TypeScript', function() {
           },
           parserConfig,
         ),
+        test (
+          {
+            code: 'export interface foo { bar: string; }; export function goo() {}',
+            parser,
+          },
+          parserConfig,
+        ),
       ],
       invalid: [],
     })