new file mode 100644
--- /dev/null
+++ b/netwerk/test/unit/test_alt-data_overwrite.js
@@ -0,0 +1,205 @@
+/**
+ * Test for overwriting the alternative data in a cache entry.
+ *
+ * - run_test loads a new channel
+ * - readServerContent checks the content, and saves alt-data
+ * - cacheFlushObserver creates a new channel with "text/binary" alt-data type
+ * - readAltContent checks that it gets back alt-data and creates a channel with the dummy/null alt-data type
+ * - readServerContent2 checks that it gets regular content, from the cache and tries to overwrite the alt-data with the same representation
+ * - cacheFlushObserver2 creates a new channel with "text/binary" alt-data type
+ * - readAltContent2 checks that it gets back alt-data, and tries to overwrite with a kind of alt-data
+ * - cacheFlushObserver3 creates a new channel with "text/binary2" alt-data type
+ * - readAltContent3 checks that it gets back the newly saved alt-data
+ */
+
+Cu.import("resource://testing-common/httpd.js");
+Cu.import("resource://gre/modules/NetUtil.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+
+XPCOMUtils.defineLazyGetter(this, "URL", function() {
+ return "http://localhost:" + httpServer.identity.primaryPort + "/content";
+});
+
+let httpServer = null;
+
+function make_and_open_channel(url, altContentType, callback) {
+ let chan = NetUtil.newChannel({uri: url, loadUsingSystemPrincipal: true});
+ if (altContentType) {
+ let cc = chan.QueryInterface(Ci.nsICacheInfoChannel);
+ cc.preferAlternativeDataType(altContentType);
+ }
+ chan.asyncOpen2(new ChannelListener(callback, null));
+}
+
+const responseContent = "response body";
+const altContent = "!@#$%^&*()";
+const altContentType = "text/binary";
+const altContent2 = "abc";
+const altContentType2 = "text/binary2";
+
+let servedNotModified = false;
+
+function contentHandler(metadata, response)
+{
+ response.setHeader("Content-Type", "text/plain");
+ response.setHeader("Cache-Control", "no-cache");
+ response.setHeader("ETag", "test-etag1");
+ let etag = ""
+ try {
+ etag = metadata.getHeader("If-None-Match");
+ } catch(ex) {
+ etag = "";
+ }
+
+ if (etag == "test-etag1") {
+ response.setStatusLine(metadata.httpVersion, 304, "Not Modified");
+ servedNotModified = true;
+ } else {
+ servedNotModified = false;
+ response.bodyOutputStream.write(responseContent, responseContent.length);
+ }
+}
+
+function run_test()
+{
+ do_get_profile();
+ httpServer = new HttpServer();
+ httpServer.registerPathHandler("/content", contentHandler);
+ httpServer.start(-1);
+
+ do_test_pending();
+ make_and_open_channel(URL, altContentType, readServerContent);
+}
+
+function readServerContent(request, buffer)
+{
+ let cc = request.QueryInterface(Ci.nsICacheInfoChannel);
+
+ do_check_eq(buffer, responseContent);
+ do_check_eq(cc.alternativeDataType, "");
+
+ do_execute_soon(() => {
+ let os = cc.openAlternativeOutputStream(altContentType);
+ os.write(altContent, altContent.length);
+ os.close();
+
+ do_execute_soon(flushAndOpenAltChannel);
+ });
+}
+
+function flushAndOpenAltChannel()
+{
+ // We need to do a GC pass to ensure the cache entry has been freed.
+ gc();
+ Services.cache2.QueryInterface(Ci.nsICacheTesting).flush(cacheFlushObserver);
+}
+
+// needs to be rooted
+let cacheFlushObserver = { observe: function() {
+ if (!cacheFlushObserver) {
+ do_print("ignoring cacheFlushObserver\n");
+ return;
+ }
+ cacheFlushObserver = null;
+ gc();
+ make_and_open_channel(URL, altContentType, readAltContent);
+}};
+
+function readAltContent(request, buffer, closure, fromCache)
+{
+ gc();
+ let cc = request.QueryInterface(Ci.nsICacheInfoChannel);
+
+ do_check_eq(fromCache || servedNotModified, true);
+ do_check_eq(cc.alternativeDataType, altContentType);
+ do_check_eq(buffer, altContent);
+
+ make_and_open_channel(URL, "dummy/null", readServerContent2);
+}
+
+function readServerContent2(request, buffer, closure, fromCache)
+{
+ gc();
+ let cc = request.QueryInterface(Ci.nsICacheInfoChannel);
+
+ do_check_eq(fromCache || servedNotModified, true);
+ do_check_eq(buffer, responseContent);
+ do_check_eq(cc.alternativeDataType, "");
+
+ do_execute_soon(() => {
+ let os = cc.openAlternativeOutputStream(altContentType);
+ os.write(altContent, altContent.length);
+ os.close();
+
+ do_execute_soon(flushAndOpenAltChannel2);
+ });
+}
+
+function flushAndOpenAltChannel2()
+{
+ // We need to do a GC pass to ensure the cache entry has been freed.
+ gc();
+ Services.cache2.QueryInterface(Ci.nsICacheTesting).flush(cacheFlushObserver2);
+}
+
+// needs to be rooted
+let cacheFlushObserver2 = { observe: function() {
+ if (!cacheFlushObserver2) {
+ do_print("ignoring cacheFlushObserver2\n");
+ return;
+ }
+ cacheFlushObserver2 = null;
+ gc();
+ make_and_open_channel(URL, altContentType, readAltContent2);
+}};
+
+function readAltContent2(request, buffer, closure, fromCache)
+{
+ gc();
+ let cc = request.QueryInterface(Ci.nsICacheInfoChannel);
+
+ do_check_eq(servedNotModified || fromCache, true);
+ do_check_eq(cc.alternativeDataType, altContentType);
+ do_check_eq(buffer, altContent);
+
+ do_execute_soon(() => {
+ gc();
+ do_print("writing other content\n");
+ let os = cc.openAlternativeOutputStream(altContentType2);
+ os.write(altContent2, altContent2.length);
+ os.close();
+
+ do_execute_soon(flushAndOpenAltChannel3);
+ });
+}
+
+function flushAndOpenAltChannel3()
+{
+ // We need to do a GC pass to ensure the cache entry has been freed.
+ gc();
+ Services.cache2.QueryInterface(Ci.nsICacheTesting).flush(cacheFlushObserver3);
+}
+
+// needs to be rooted
+let cacheFlushObserver3 = { observe: function() {
+ if (!cacheFlushObserver3) {
+ do_print("ignoring cacheFlushObserver3\n");
+ return;
+ }
+
+ cacheFlushObserver3 = null;
+ gc();
+ make_and_open_channel(URL, altContentType2, readAltContent3);
+}};
+
+
+function readAltContent3(request, buffer, closure, fromCache)
+{
+ let cc = request.QueryInterface(Ci.nsICacheInfoChannel);
+
+ do_check_eq(servedNotModified || fromCache, true);
+ do_check_eq(cc.alternativeDataType, altContentType2);
+ do_check_eq(buffer, altContent2);
+
+ httpServer.stop(do_test_finished);
+}