From d480f4d4f5b4dfc05c9ffd44a623535a7b37675d Mon Sep 17 00:00:00 2001
From: David Buchan-Swanson <david.buchanswanson@gmail.com>
Date: Tue, 19 Sep 2017 13:35:27 +1000
Subject: [PATCH] feat: add an auto-fix option to sortKeys

---
 src/rules/sortKeys.js              | 36 ++++++++++++++++++++++++++++++
 tests/rules/assertions/sortKeys.js | 22 ++++++++++++++++++
 2 files changed, 58 insertions(+)

diff --git a/src/rules/sortKeys.js b/src/rules/sortKeys.js
index 5570c3d1..6fce3cb0 100644
--- a/src/rules/sortKeys.js
+++ b/src/rules/sortKeys.js
@@ -65,6 +65,17 @@ const isValidOrders = {
   }
 };
 
+const generateOrderedList = (context, sort, properties) => {
+  return properties.map((property) => {
+    const name = getParameterName(property, context);
+    const value = context.getSourceCode().getFirstToken(property.value).value;
+
+    return [name, value];
+  })
+    .sort((first, second) => { return sort(first[0], second[0]) ? -1 : 1; })
+    .map((item) => { return item[0] + ': ' + item[1]; });
+};
+
 const create = (context) => {
   const order = _.get(context, ['options', 0], 'asc');
   const {natural, caseSensitive} = _.get(context, ['options', 1], defaults);
@@ -96,6 +107,31 @@ const create = (context) => {
             natural: natural ? 'natural ' : '',
             order
           },
+          fix (fixer) {
+            // this could be done much more cleanly in ESLint >=4
+            // as we can apply multiple fixes. That also means we can
+            // maintain code style in a much nicer way
+            let nodeText;
+            const newTypes = generateOrderedList(context, isValidOrder, node.properties);
+            const source = context.getSourceCode(node);
+
+            const originalSubstring = source.getText(node);
+
+            nodeText = originalSubstring;
+
+            node.properties.forEach((property, index) => {
+              const subString = source.getText(property);
+              const addComma = subString[subString.length - 1] === ',';
+
+              nodeText = nodeText.replace(subString, '$' + index + (addComma ? ',' : ''));
+            });
+
+            newTypes.forEach((item, index) => {
+              nodeText = nodeText.replace('$' + index, item);
+            });
+
+            return fixer.replaceText(node, nodeText);
+          },
           loc: identifierNode.loc,
           message: 'Expected type annotations to be in {{natural}}{{insensitive}}{{order}}ending order. "{{current}}" should be before "{{last}}".',
           node: identifierNode
diff --git a/tests/rules/assertions/sortKeys.js b/tests/rules/assertions/sortKeys.js
index 06ec998c..60b408bb 100644
--- a/tests/rules/assertions/sortKeys.js
+++ b/tests/rules/assertions/sortKeys.js
@@ -41,6 +41,28 @@ export default {
       code: 'type FooType = { 1: number, 10: number, 2: boolean }',
       errors: [{message: 'Expected type annotations to be in natural ascending order. "2" should be before "10".'}],
       options: ['asc', {natural: true}]
+    },
+    {
+      code: 'type FooType = { a: number, c: number, b: string }',
+      errors: [{message: 'Expected type annotations to be in ascending order. "b" should be before "c".'}],
+      output: 'type FooType = { a: number, b: string, c: number }'
+    },
+    {
+      code: [
+        'type FooType = {',
+        '  a: number,',
+        '  c: number,',
+        '  b: string,',
+        '}'
+      ].join('\n'),
+      errors: [{message: 'Expected type annotations to be in ascending order. "b" should be before "c".'}],
+      output: [
+        'type FooType = {',
+        '  a: number,',
+        '  b: string,',
+        '  c: number,',
+        '}'
+      ].join('\n')
     }
   ],
   misconfigured: [