From ef246a9387f45bb0988887cfdbfab86bc3650fb2 Mon Sep 17 00:00:00 2001
From: Alexander Afanasyev <afanasieffav@gmail.com>
Date: Fri, 8 Jul 2016 20:17:27 -0400
Subject: [PATCH] feat(rules): 'use-first-last' rule to apply fixes

---
 lib/rules/use-first-last.js  | 69 +++++++++++++++++++++++-------------
 test/rules/use-first-last.js | 30 ++++++++++++----
 2 files changed, 69 insertions(+), 30 deletions(-)

diff --git a/lib/rules/use-first-last.js b/lib/rules/use-first-last.js
index 73e5365..cfe0b36 100644
--- a/lib/rules/use-first-last.js
+++ b/lib/rules/use-first-last.js
@@ -5,38 +5,59 @@
  * @author Alexander Afanasyev
  */
 
-module.exports = function (context) {
-  var valueFunction = {
-    '0': 'first()',
-    '-1': 'last()'
-  }
+var valueFunction = {
+  '0': 'first()',
+  '-1': 'last()'
+}
+
+module.exports = {
+  meta: {
+    fixable: 'code'
+  },
 
-  function getFirstArgumentValue (methodArguments) {
-    var firstArgument = methodArguments[0]
+  create: function (context) {
+    function getFirstArgumentValue (methodArguments) {
+      var firstArgument = methodArguments[0]
 
-    if (firstArgument) {
-      if (firstArgument.value === 0) {
-        return 0
-      } else if (firstArgument.operator === '-') {
-        return -firstArgument.argument.value
+      if (firstArgument) {
+        if (firstArgument.value === 0) {
+          return 0
+        } else if (firstArgument.operator === '-') {
+          return -firstArgument.argument.value
+        }
+      }
+    }
+
+    function createFirstLastAutoFixFunction (property, argument, argumentValue) {
+      var functionToUse = valueFunction[argumentValue]
+      var rangeStart = property.range[0]
+      var rangeEnd = argument.range[1] + 1  // 1 added for parenthesis
+
+      return function (fixer) {
+        // replace get(0) with first(), get(-1) with last()
+        return fixer.replaceTextRange([rangeStart, rangeEnd], functionToUse)
       }
     }
-  }
 
-  return {
-    CallExpression: function (node) {
-      var property = node.callee.property
+    return {
+      CallExpression: function (node) {
+        var property = node.callee.property
 
-      if (property && property.name === 'get' && node.arguments) {
-        var argumentValue = getFirstArgumentValue(node.arguments)
+        if (property && property.name === 'get' && node.arguments) {
+          var argumentValue = getFirstArgumentValue(node.arguments)
 
-        if (argumentValue === 0 || argumentValue === -1) {
-          var object = node.callee.object
-          var callee = object.callee
+          if (argumentValue === 0 || argumentValue === -1) {
+            var object = node.callee.object
+            var callee = object.callee
 
-          if (callee && ((callee.property && (callee.property.name === 'all' || callee.property.name === '$$')) ||
-            (callee.name === '$$'))) {
-            context.report(node, 'Unexpected "get(' + argumentValue + ')" call, use "' + valueFunction[argumentValue] + '" instead')
+            if (callee && ((callee.property && (callee.property.name === 'all' || callee.property.name === '$$')) ||
+              (callee.name === '$$'))) {
+              context.report({
+                node: callee,
+                message: 'Unexpected "get(' + argumentValue + ')" call, use "' + valueFunction[argumentValue] + '" instead',
+                fix: createFirstLastAutoFixFunction(property, node.arguments[0], argumentValue)
+              })
+            }
           }
         }
       }
diff --git a/test/rules/use-first-last.js b/test/rules/use-first-last.js
index bb4a500..c202574 100644
--- a/test/rules/use-first-last.js
+++ b/test/rules/use-first-last.js
@@ -27,7 +27,8 @@ eslintTester.run('use-first-last', rule, {
         {
           message: 'Unexpected "get(0)" call, use "first()" instead'
         }
-      ]
+      ],
+      output: 'element.all(by.css(".class")).first();'
     },
     {
       code: 'element(by.id("id")).all(by.css(".class")).get(-1);',
@@ -35,7 +36,8 @@ eslintTester.run('use-first-last', rule, {
         {
           message: 'Unexpected "get(-1)" call, use "last()" instead'
         }
-      ]
+      ],
+      output: 'element(by.id("id")).all(by.css(".class")).last();'
     },
     {
       code: '$$(".class").get(0);',
@@ -43,7 +45,8 @@ eslintTester.run('use-first-last', rule, {
         {
           message: 'Unexpected "get(0)" call, use "first()" instead'
         }
-      ]
+      ],
+      output: '$$(".class").first();'
     },
     {
       code: 'element(by.id("id")).$$(".class").get(-1);',
@@ -51,7 +54,8 @@ eslintTester.run('use-first-last', rule, {
         {
           message: 'Unexpected "get(-1)" call, use "last()" instead'
         }
-      ]
+      ],
+      output: 'element(by.id("id")).$$(".class").last();'
     },
     {
       code: 'element.all(by.css(".class")).get(0).getText();',
@@ -59,7 +63,8 @@ eslintTester.run('use-first-last', rule, {
         {
           message: 'Unexpected "get(0)" call, use "first()" instead'
         }
-      ]
+      ],
+      output: 'element.all(by.css(".class")).first().getText();'
     },
     {
       code: 'element.all(by.css(".class")).get(-1).getText();',
@@ -67,7 +72,20 @@ eslintTester.run('use-first-last', rule, {
         {
           message: 'Unexpected "get(-1)" call, use "last()" instead'
         }
-      ]
+      ],
+      output: 'element.all(by.css(".class")).last().getText();'
+    },
+    {
+      code: 'element.all(by.css(".class")).get(-1).all(by.css(".anotherclass")).get(0).getText();',
+      errors: [
+        {
+          message: 'Unexpected "get(0)" call, use "first()" instead'
+        },
+        {
+          message: 'Unexpected "get(-1)" call, use "last()" instead'
+        }
+      ],
+      output: 'element.all(by.css(".class")).last().all(by.css(".anotherclass")).first().getText();'
     }
   ]
 })