From 3d981011e9a251742d263e08113045b20e4c5901 Mon Sep 17 00:00:00 2001
From: Kyle Huey <khuey@kylehuey.com>
Date: Thu, 30 Jun 2011 14:42:15 -0700
Subject: [PATCH] Bug 661582: XHR.response should return a Blob, not a File.
 r=sicking

---
 content/base/src/nsXMLHttpRequest.cpp | 33 +++++++++++++++++++++++----
 content/base/test/test_XHR.html       |  2 ++
 2 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/content/base/src/nsXMLHttpRequest.cpp b/content/base/src/nsXMLHttpRequest.cpp
index 6f21c7b0f92..be232ea679f 100644
--- a/content/base/src/nsXMLHttpRequest.cpp
+++ b/content/base/src/nsXMLHttpRequest.cpp
@@ -1620,9 +1620,21 @@ void nsXMLHttpRequest::CreateResponseBlob(nsIRequest *request)
     if (cc) {
       cc->GetCacheToken(getter_AddRefs(cacheToken));
     }
-    mResponseBlob = new nsDOMFile(file,
-                                  NS_ConvertASCIItoUTF16(contentType),
-                                  cacheToken);
+
+    NS_ConvertASCIItoUTF16 wideContentType(contentType);
+
+    nsCOMPtr<nsIDOMBlob> blob =
+      new nsDOMFile(file, wideContentType, cacheToken);
+
+    // XXXkhuey this is a complete hack ... but we need to get 6 out the door
+    // The response blob here should not be a File object, it should only
+    // be a Blob.  Unfortunately, because nsDOMFile has grown through
+    // accretion over the years and is in dangerous need of a refactoring,
+    // slicing it is the easiest way to get there ...
+    PRUint64 size = 0;
+    blob->GetSize(&size);
+    blob->MozSlice(0, size, wideContentType, 2, getter_AddRefs(mResponseBlob));
+    
     mResponseBody.Truncate();
     mResponseBodyUnicode.SetIsVoid(PR_TRUE);
   }
@@ -1893,9 +1905,20 @@ nsXMLHttpRequest::OnStopRequest(nsIRequest *request, nsISupports *ctxt, nsresult
       void *blobData = PR_Malloc(blobLen);
       if (blobData) {
         memcpy(blobData, mResponseBody.BeginReading(), blobLen);
-        mResponseBlob =
+
+        NS_ConvertASCIItoUTF16 wideContentType(contentType);
+        nsCOMPtr<nsIDOMBlob> blob =
           new nsDOMMemoryFile(blobData, blobLen, EmptyString(),
-                              NS_ConvertASCIItoUTF16(contentType));
+                              wideContentType);
+
+        // XXXkhuey this is a complete hack ... but we need to get 6 out the door
+        // The response blob here should not be a File object, it should only
+        // be a Blob.  Unfortunately, because nsDOMFile has grown through
+        // accretion over the years and is in dangerous need of a refactoring,
+        // slicing it is the easiest way to get there ...
+        blob->MozSlice(0, blobLen, wideContentType,
+                       2, getter_AddRefs(mResponseBlob));
+
         mResponseBody.Truncate();
       }
       NS_ASSERTION(mResponseBodyUnicode.IsVoid(),
diff --git a/content/base/test/test_XHR.html b/content/base/test/test_XHR.html
index 4f370b34969..7c3a221a8ee 100644
--- a/content/base/test/test_XHR.html
+++ b/content/base/test/test_XHR.html
@@ -160,6 +160,8 @@ checkResponseTextAccessThrows(xhr);
 checkResponseXMLAccessThrows(xhr);
 b = xhr.response;
 ok(b, "should have a non-null blob");
+ok(b instanceof Blob, "should be a Blob");
+ok(!(b instanceof File), "should not be a File");
 is(b.size, "hello pass\n".length, "wrong blob size");
 
 var fr = new FileReader();