Fix prop-types crash when accessing constructor on props (fixes #654)

Author: yannickcr

lib/rules/prop-types.js

@@ -168,10 +168,12 @@ module.exports = Components.detect(function(context, components, utils) {
     for (var i = 0, j = keyList.length; i < j; i++) {
       var key = keyList[i];
       var propType = (
-        // Check if this key is declared
-        declaredPropTypes[key] ||
-        // If not, check if this type accepts any key
-        declaredPropTypes.__ANY_KEY__
+        declaredPropTypes && (
+          // Check if this key is declared
+          declaredPropTypes[key] ||
+          // If not, check if this type accepts any key
+          declaredPropTypes.__ANY_KEY__
+        )
       );
 
       if (!propType) {

tests/lib/rules/prop-types.js

@@ -2206,6 +2206,21 @@ ruleTester.run('prop-types', rule, {
         {message: '\'firstname\' is missing in props validation'},
         {message: '\'lastname\' is missing in props validation'}
       ]
+    }, {
+      code: [
+        'function Hello(props) {',
+        '  return <div>{props.name.constructor.firstname}</div>',
+        '}',
+        'Hello.propTypes = {',
+        '  name: PropTypes.shape({',
+        '    firstname: PropTypes.object',
+        '  })',
+        '};'
+      ].join('\n'),
+      parser: 'babel-eslint',
+      errors: [
+        {message: '\'name.constructor.firstname\' is missing in props validation'}
+      ]
     }
   ]
 });