From b1a949ed455dbecc1d7c868d723c76576ae713f9 Mon Sep 17 00:00:00 2001
From: "Fabio M. Costa" <fabiomcosta@gmail.com>
Date: Fri, 27 Dec 2013 16:42:57 -0800
Subject: [PATCH 1/3] Adds the filename to JSXTransform error message, making
 it easier to debug JSX syntax errors.

---
 vendor/browser-transforms.js | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/vendor/browser-transforms.js b/vendor/browser-transforms.js
index f6a6980c691b..0bcf7f096258 100644
--- a/vendor/browser-transforms.js
+++ b/vendor/browser-transforms.js
@@ -41,7 +41,20 @@ var transformCode = function(code, source) {
   var jsx = docblock.parseAsObject(docblock.extract(code)).jsx;
 
   if (jsx) {
-    var transformed = transformReact(code);
+    try {
+      var transformed = transformReact(code);
+    } catch(e) {
+      if (source) {
+        if ('fileName' in e) {
+          // We set `fileName` if it's supported by this error object and
+          // a `source` was provided.
+          // The error will correctly point to `source` in Firefox.
+          e.fileName = source;
+        }
+        e.message += '\n    at ' + source + ':' + e.lineNumber + ':' + e.column;
+      }
+      throw e;
+    }
 
     var map = transformed.sourceMap.toJSON();
     if (source == null) {
@@ -98,7 +111,7 @@ var load = exports.load = function(url, callback) {
 
 runScripts = function() {
   var scripts = document.getElementsByTagName('script');
-  
+
   // Array.prototype.slice cannot be used on NodeList on IE8
   var jsxScripts = [];
   for (var i = 0; i < scripts.length; i++) {
@@ -106,7 +119,7 @@ runScripts = function() {
       jsxScripts.push(scripts.item(i));
     }
   }
-  
+
   console.warn("You are using the in-browser JSX transformer. Be sure to precompile your JSX for production - http://facebook.github.io/react/docs/tooling-integration.html#jsx");
 
   jsxScripts.forEach(function(script) {

From d829d1ab9b9c8e6a3a07fb987f609be3f71d081c Mon Sep 17 00:00:00 2001
From: "Fabio M. Costa" <fabiomcosta@gmail.com>
Date: Fri, 27 Dec 2013 19:38:53 -0800
Subject: [PATCH 2/3] Adding current page's url for inline code and code
 improvement

---
 vendor/browser-transforms.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/vendor/browser-transforms.js b/vendor/browser-transforms.js
index 0bcf7f096258..6e9319a14eb5 100644
--- a/vendor/browser-transforms.js
+++ b/vendor/browser-transforms.js
@@ -44,6 +44,7 @@ var transformCode = function(code, source) {
     try {
       var transformed = transformReact(code);
     } catch(e) {
+      e.message += '\n    at ';
       if (source) {
         if ('fileName' in e) {
           // We set `fileName` if it's supported by this error object and
@@ -51,7 +52,9 @@ var transformCode = function(code, source) {
           // The error will correctly point to `source` in Firefox.
           e.fileName = source;
         }
-        e.message += '\n    at ' + source + ':' + e.lineNumber + ':' + e.column;
+        e.message += source + ':' + e.lineNumber + ':' + e.column;
+      } else {
+        e.message += location.href;
       }
       throw e;
     }

From de7a92afa703d27cf05f176b2bbd176beb03ea52 Mon Sep 17 00:00:00 2001
From: "Fabio M. Costa" <fabiomcosta@gmail.com>
Date: Sun, 29 Dec 2013 19:40:16 -0800
Subject: [PATCH 3/3] Updating error message to also show part of the code,
 making it easier to find the error

---
 vendor/browser-transforms.js | 38 ++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/vendor/browser-transforms.js b/vendor/browser-transforms.js
index 6e9319a14eb5..701693c34a7c 100644
--- a/vendor/browser-transforms.js
+++ b/vendor/browser-transforms.js
@@ -37,6 +37,43 @@ exports.exec = function(code) {
 
 var inlineScriptCount = 0;
 
+// This method returns a nicely formated line of code pointing the
+// exactly location of the error `e`.
+// The line is limited in size so big lines of code are also shown
+// in a readable way.
+// Example:
+//
+// ... x', overflow:'scroll'}} id={} onScroll={this.scroll} class=" ...
+//                                 ^
+var createSourceCodeErrorMessage = function(code, e) {
+  var sourceLines = code.split('\n');
+  var erroneousLine = sourceLines[e.lineNumber - 1];
+
+  // Removes any leading indenting spaces and gets the number of
+  // chars indenting the `erroneousLine`
+  var indentation = 0;
+  erroneousLine = erroneousLine.replace(/^\s+/, function(leadingSpaces) {
+    indentation = leadingSpaces.length;
+    return '';
+  });
+
+  // Defines the number of characters that are going to show
+  // before and after the erroneous code
+  var LIMIT = 30;
+  var errorColumn = e.column - indentation;
+
+  if (errorColumn > LIMIT) {
+    erroneousLine = '... ' + erroneousLine.slice(errorColumn - LIMIT);
+    errorColumn = 4 + LIMIT;
+  }
+  if (erroneousLine.length - errorColumn > LIMIT) {
+    erroneousLine = erroneousLine.slice(0, errorColumn + LIMIT) + ' ...';
+  }
+  var message = '\n\n' + erroneousLine + '\n';
+  message += new Array(errorColumn - 1).join(' ') + '^';
+  return message;
+};
+
 var transformCode = function(code, source) {
   var jsx = docblock.parseAsObject(docblock.extract(code)).jsx;
 
@@ -56,6 +93,7 @@ var transformCode = function(code, source) {
       } else {
         e.message += location.href;
       }
+      e.message += createSourceCodeErrorMessage(code, e);
       throw e;
     }