add no-when rule

Author: alunny

README.md

@@ -68,6 +68,7 @@ Add `jquery` to the plugins section of your `.eslintrc` configuration file. You
     "jquery/no-trigger": 2,
     "jquery/no-trim": 2,
     "jquery/no-val": 2,
+    "jquery/no-when": 2,
     "jquery/no-wrap": 2
   }
 }

index.js

@@ -42,6 +42,7 @@ module.exports = {
     'no-trigger': require('./rules/no-trigger'),
     'no-trim': require('./rules/no-trim'),
     'no-val': require('./rules/no-val'),
+    'no-when': require('./rules/no-when'),
     'no-wrap': require('./rules/no-wrap')
   },
   configs: {
@@ -87,6 +88,7 @@ module.exports = {
         "jquery/no-trigger": 2,
         "jquery/no-trim": 2,
         "jquery/no-val": 2,
+        "jquery/no-when": 2,
         "jquery/no-wrap": 2
       }
     },

rules/no-when.js

@@ -0,0 +1,18 @@
+'use strict';
+
+module.exports = function(context) {
+  return {
+    CallExpression: function(node) {
+      if (node.callee.type !== 'MemberExpression') return
+      if (node.callee.object.name !== '$') return
+      if (node.callee.property.name !== 'when') return
+
+      context.report({
+        node: node,
+        message: 'Prefer Promise.all to $.when'
+      })
+    }
+  }
+}
+
+module.exports.schema = []

tests/no-when.js

@@ -0,0 +1,23 @@
+'use strict';
+
+const rule = require('../rules/no-when')
+const RuleTester = require('eslint').RuleTester
+
+const error = 'Prefer Promise.all to $.when'
+
+const ruleTester = new RuleTester()
+ruleTester.run('no-when', rule, {
+  valid: [
+    'When()',
+    'new When()',
+    '"test".when()',
+    '"test".when',
+    '$when()'
+  ],
+  invalid: [
+    {
+      code: '$.when(a,b)',
+      errors: [{message: error, type: 'CallExpression'}]
+    }
+  ]
+})