Fix used props detection in components for which we are not confident (…

…fixes #420)

lib/util/Components.js

@@ -77,11 +77,33 @@ Components.prototype.set = function(node, props) {
  */
 Components.prototype.list = function() {
   var list = {};
+  var usedPropTypes = {};
+  // Find props used in components for which we are not confident
   for (var i in this._list) {
-    if (!this._list.hasOwnProperty(i) || this._list[i].confidence < 2) {
+    if (!this._list.hasOwnProperty(i) || this._list[i].confidence >= 2) {
       continue;
     }
-    list[i] = this._list[i];
+    var component;
+    var node;
+    node = this._list[i].node;
+    while (!component && node.parent) {
+      node = node.parent;
+      component = this.get(node);
+    }
+    if (component) {
+      usedPropTypes[this._getId(component.node)] = this._list[i].usedPropTypes;
+    }
+  }
+  // Assign used props in not confident components to the parent component
+  for (var j in this._list) {
+    if (!this._list.hasOwnProperty(j) || this._list[j].confidence < 2) {
+      continue;
+    }
+    var id = this._getId(this._list[j].node);
+    list[j] = this._list[j];
+    if (usedPropTypes[id]) {
+      list[j].usedPropTypes = (list[j].usedPropTypes || []).concat(usedPropTypes[id]);
+    }
   }
   return list;
 };

tests/lib/rules/prop-types.js

@@ -1937,6 +1937,16 @@ ruleTester.run('prop-types', rule, {
       errors: [{
         message: '\'names\' is missing in props validation'
       }]
+    }, {
+      code: [
+        'const MyComponent = props => (',
+        '  <div onClick={() => props.toggle()}></div>',
+        ')'
+      ].join('\n'),
+      parserOptions: parserOptions,
+      errors: [{
+        message: '\'toggle\' is missing in props validation'
+      }]
     }
   ]
 });