From e06f09a925fea9993f727e5bed1cd6bbdc448e43 Mon Sep 17 00:00:00 2001
From: Gajus Kuizinas <gajus@gajus.com>
Date: Fri, 15 May 2020 17:07:46 -0700
Subject: [PATCH] fix: support shebang (fixes #416)

---
 src/rules/requireValidFileAnnotation.js       | 13 ++++++++++
 .../assertions/requireValidFileAnnotation.js  | 24 +++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/src/rules/requireValidFileAnnotation.js b/src/rules/requireValidFileAnnotation.js
index e6643ab2..51265988 100644
--- a/src/rules/requireValidFileAnnotation.js
+++ b/src/rules/requireValidFileAnnotation.js
@@ -124,6 +124,19 @@ const create = (context) => {
               annotation = ['line', 'none'].includes(style) ? '// @flow\n' : '/* @flow */\n';
             }
 
+            const firstComment = node.comments[0];
+
+            if (firstComment && firstComment.type === 'Shebang') {
+              return fixer
+                .replaceTextRange(
+                  [
+                    firstComment.range[1],
+                    firstComment.range[1],
+                  ],
+                  '\n' + annotation.trim(),
+                );
+            }
+
             return fixer
               .replaceTextRange(
                 [
diff --git a/tests/rules/assertions/requireValidFileAnnotation.js b/tests/rules/assertions/requireValidFileAnnotation.js
index c2b627f6..5db3ebb9 100644
--- a/tests/rules/assertions/requireValidFileAnnotation.js
+++ b/tests/rules/assertions/requireValidFileAnnotation.js
@@ -1,5 +1,29 @@
 export default {
   invalid: [
+    {
+      code: '#!/usr/bin/env node',
+      errors: [
+        {
+          message: 'Flow file annotation is missing.',
+        },
+      ],
+      options: [
+        'always',
+      ],
+      output: '#!/usr/bin/env node\n// @flow',
+    },
+    {
+      code: '#!/usr/bin/env node\na;',
+      errors: [
+        {
+          message: 'Flow file annotation is missing.',
+        },
+      ],
+      options: [
+        'always',
+      ],
+      output: '#!/usr/bin/env node\n// @flow\na;',
+    },
     {
       code: ';// @flow',
       errors: [