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Libraries/JavaScriptAppEngine/Initialization/__mocks__/SourceMapsCache.js

@@ -0,0 +1,19 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+'use strict';
+
+const SourceMapsCache = jest.genMockFromModule('SourceMapsCache');
+
+var getSourceMaps = jest.genMockFunction();
+const promise = new Promise((resolve, reject) => resolve({}));
+
+getSourceMaps.mockReturnValue(promise);
+SourceMapsCache.getSourceMaps = getSourceMaps;
+
+module.exports = SourceMapsCache;

Libraries/JavaScriptAppEngine/Initialization/__mocks__/parseErrorStack.js

@@ -0,0 +1,22 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+'use strict';
+
+const parseErrorStack = jest.genMockFunction();
+
+const frame = [{
+  file: '/Examples/UIExplorer/ViewExample.js',
+  methodName: 'Constructor.render',
+  lineNumber: 42,
+  column: 0
+}];
+
+parseErrorStack.mockReturnValue(frame);
+
+module.exports = parseErrorStack;

Libraries/JavaScriptAppEngine/Initialization/__tests__/exceptionOccurHint-test.js

@@ -0,0 +1,22 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+'use strict';
+
+jest.unmock('../exceptionOccurHint');
+
+const exceptionOccurHint = require('exceptionOccurHint');
+
+describe('exceptionOccurHint', () => {
+
+  pit('give a hint', () => {
+    return exceptionOccurHint().then(hint => {
+      expect(hint).toEqual('At: ViewExample.js:42');
+    });
+  });
+});

Libraries/JavaScriptAppEngine/Initialization/exceptionOccurHint.js

@@ -0,0 +1,34 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @providesModule exceptionOccurHint
+ */
+
+'use strict';
+
+const SourceMapsCache = require('SourceMapsCache');
+const parseErrorStack = require('parseErrorStack');
+
+function exceptionOccurHint() {
+  const stack =  parseErrorStack(new Error());
+  const renderFrame = stack.find((frame) => frame.methodName.endsWith('render'));
+
+  if (renderFrame) {
+    return SourceMapsCache.getSourceMaps().then(sourceMaps => {
+      const prettyStack = parseErrorStack({stack: [renderFrame]}, sourceMaps);
+      const prettyFrame = prettyStack[0];
+      const fileParts = prettyFrame.file.split('/');
+      const fileName = fileParts[fileParts.length - 1];
+      return `At: ${fileName }:${prettyFrame.lineNumber}`;
+    });
+  } else {
+    return new Promise((resolve, reject) => resolve(null));
+  }
+}
+
+module.exports = exceptionOccurHint;

Libraries/ReactIOS/YellowBox.js

@@ -17,6 +17,7 @@ import type EmitterSubscription from 'EmitterSubscription';
 const Platform = require('Platform');
 const React = require('React');
 const StyleSheet = require('StyleSheet');
+const exceptionOccurHint = require('exceptionOccurHint');
 
 const _warningEmitter = new EventEmitter();
 const _warningMap = new Map();
@@ -82,9 +83,23 @@ function updateWarningMap(format, ...args): void {
     ...args.slice(argCount).map(stringifySafe),
   ].join(' ');
 
-  const count = _warningMap.has(warning) ? _warningMap.get(warning) : 0;
-  _warningMap.set(warning, count + 1);
+  var warningInfo = _warningMap.get(warning);
+  if (warningInfo) {
+    warningInfo.count += 1;
+  } else {
+    warningInfo = {count: 1, frame: ''};
+  }
+
+  _warningMap.set(warning, warningInfo);
   _warningEmitter.emit('warning', _warningMap);
+
+  exceptionOccurHint().then((frame) => {
+    warningInfo = _warningMap.get(warning);
+    if (warningInfo && frame) {
+      warningInfo.frame = frame;
+      _warningEmitter.emit('warning', _warningMap);
+    }
+  });
 }
 
 function isWarningIgnored(warning: string): boolean {
@@ -123,6 +138,7 @@ const WarningRow = ({count, warning, onPress}) => {
 
 const WarningInspector = ({
   count,
+  frame,
   warning,
   onClose,
   onDismiss,
@@ -145,6 +161,7 @@ const WarningInspector = ({
       <View style={styles.inspectorContent}>
         <View style={styles.inspectorCount}>
           <Text style={styles.inspectorCountText}>{countSentence}</Text>
+          <Text style={styles.inspectorCountText}>{frame}</Text>
         </View>
         <ScrollView style={styles.inspectorWarning}>
           <Text style={styles.inspectorWarningText}>{warning}</Text>
@@ -230,9 +247,12 @@ class YellowBox extends React.Component {
     const View = require('View');
 
     const inspecting = this.state.inspecting;
-    const inspector = inspecting !== null ?
+    const inspectingWarningInfo = this.state.warningMap.get(inspecting);
+
+    const inspector = inspecting !== null && inspectingWarningInfo !== null ?
       <WarningInspector
-        count={this.state.warningMap.get(inspecting)}
+        count={inspectingWarningInfo.count}
+        frame={inspectingWarningInfo.frame}
         warning={inspecting}
         onClose={() => this.setState({inspecting: null})}
         onDismiss={() => this.dismissWarning(inspecting)}
@@ -241,12 +261,12 @@ class YellowBox extends React.Component {
       null;
 
     const rows = [];
-    this.state.warningMap.forEach((count, warning) => {
+    this.state.warningMap.forEach((warningInfo, warning) => {
       if (!isWarningIgnored(warning)) {
         rows.push(
           <WarningRow
             key={warning}
-            count={count}
+            count={warningInfo.count}
             warning={warning}
             onPress={() => this.setState({inspecting: warning})}
             onDismiss={() => this.dismissWarning(warning)}
@@ -324,7 +344,7 @@ var styles = StyleSheet.create({
   inspectorWarning: {
     padding: 15,
     position: 'absolute',
-    top: 39,
+    top: 50,
     bottom: 60,
   },
   inspectorWarningText: {