Add regression test

Author: ertrzyiks

tests/src/rules/no-duplicates.js

@@ -48,6 +48,49 @@ ruleTester.run('no-duplicates', rule, {
     test({
       code: "import {y} from './foo'; import * as ns from './foo'",
     }),
+
+    // #2027 long import list generate empty lines
+    test({
+      code: `
+        import { One } from '../fragments/one'
+        import { Two } from '../fragments/two'
+        import { Three } from '../fragments/three'
+        import { Four } from '../fragments/four'
+        import { Five } from '../fragments/five'
+        import { Six } from '../fragments/six'
+        import { Seven } from '../fragments/seven'
+        import { Eight } from '../fragments/eight'
+        import { Nine } from '../fragments/nine'
+        import { Ten } from '../fragments/ten'
+        import { Eleven } from '../fragments/eleven'
+        import { OneDoc } from '../fragments/one'
+        import { TwoDoc } from '../fragments/two'
+        import { ThreeDoc } from '../fragments/three'
+        import { FourDoc } from '../fragments/four'
+        import { FiveDoc } from '../fragments/five'
+        import { SixDoc } from '../fragments/six'
+        import { SevenDoc } from '../fragments/seven'
+        import { EightDoc } from '../fragments/eight'
+        import { NineDoc } from '../fragments/nine'
+        import { TenDoc } from '../fragments/ten'
+        import { ElevenDoc } from '../fragments/eleven'
+        export const vars = {}
+      `,
+      output: `
+        import { One, OneDoc } from '../fragments/one'
+        import { Two, TwoDoc } from '../fragments/two'
+        import { Three, ThreeDoc } from '../fragments/three'
+        import { Four, FourDoc } from '../fragments/four'
+        import { Five, FiveDoc } from '../fragments/five'
+        import { Six, SixDoc } from '../fragments/six'
+        import { Seven, SevenDoc } from '../fragments/seven'
+        import { Eight, EightDoc } from '../fragments/eight'
+        import { Nine, NineDoc } from '../fragments/nine'
+        import { Ten, TenDoc } from '../fragments/ten'
+        import { Eleven, ElevenDoc } from '../fragments/eleven'
+        export const vars = {}
+      `,
+    }),
   ],
   invalid: [
     test({