Fix no-unused-prop-types crash with destructured prop-types (fixes #938)

Author: Yannick Croissant

lib/rules/no-unused-prop-types.js

@@ -579,8 +579,10 @@ module.exports = {
           for (var i = 0, j = node.id.properties.length; i < j; i++) {
             // let {props: {firstname}} = this
             var thisDestructuring = (
-              (node.id.properties[i].key.name === 'props' || node.id.properties[i].key.value === 'props') &&
-              node.id.properties[i].value.type === 'ObjectPattern'
+              node.id.properties[i].key && (
+                (node.id.properties[i].key.name === 'props' || node.id.properties[i].key.value === 'props') &&
+                node.id.properties[i].value.type === 'ObjectPattern'
+              )
             );
             // let {firstname} = props
             var genericDestructuring = isPropAttributeName(node) && (

tests/lib/rules/no-unused-prop-types.js

@@ -1413,6 +1413,15 @@ ruleTester.run('no-unused-prop-types', rule, {
         '});'
       ].join('\n'),
       parserOptions: parserOptions
+    }, {
+      // Destructured props in a stateless function
+      code: [
+        'const Hello = (props) => {',
+        '  const {...rest} = props;',
+        '  return <div />;',
+        '};'
+      ].join('\n'),
+      parserOptions: parserOptions
     }
   ],