Fix no-danger-with-children crash with spread on global variables (fixes #921)

Author: Yannick Croissant

lib/rules/no-danger-with-children.js

@@ -56,7 +56,7 @@ module.exports = {
       return attributes.find(function (attribute) {
         if (attribute.type === 'JSXSpreadAttribute') {
           var variable = findSpreadVariable(attribute.argument.name);
-          if (variable && variable.defs[0].node.init) {
+          if (variable && variable.defs.length && variable.defs[0].node.init) {
             return findObjectProp(variable.defs[0].node.init, propName);
           }
         }

tests/lib/rules/no-danger-with-children.js

@@ -30,6 +30,13 @@ ruleTester.run('no-danger-with-children', rule, {
       code: '<div>Children</div>',
       parserOptions: parserOptions
     },
+    {
+      code: '<div {...props} />',
+      parserOptions: parserOptions,
+      globals: {
+        props: true
+      }
+    },
     {
       code: '<div dangerouslySetInnerHTML={{ __html: "HTML" }} />',
       parserOptions: parserOptions