After porting the XPCShell Unittests to Fennec, I found a few failures. These failures all appear to fail in similar places while running on the device or desktop version. From bug 468400: This testcase is failing on Fennec and after reading the code with mfinkle we were not sure why it is failing. Specifically test #3 is failing where the first returned search result is uri2 instead of uri1. Here is a reference to the test case that fails: http://mxr.mozilla.org/mozilla-central/source/toolkit/components/places/tests/unit/test_adaptive.js#246 Could I get some assistance with understanding how and why this is failing? There are a few other failures in the same test folder which I think are related.

I'm a bit confused about the "on Fennec" part of these bug reports. XPCShell tests don't invoke Fennec at all, right? Are all these bugs specific to the n810, or to the harness you're using? Or both? In other words, what's the difference between your setup and the tinderbox machines that are running these xpcshell tests successfully on the Firefox tree?

Ah, I've just read bug 477613 comment 2. Perhaps the xpcshell tests aren't as independent as I thought they were... it's still not clear to me how that dependency works, though.

OK, so two of the main problems I didn't think of are default prefs and branding. I bet differences in those two between Firefox and Fennec account for most of your failures. Perhaps you could try copying over the default firefox.js file (say from a linux Firefox build) into the right place in your Fennec application directory, and see how many of the failures go away?

Seamonkey had issues with prefs, and they changed our tests so they were still working correctly independantly from prefs, iirc. Neil could know more about that. I also think about those type issues you had with PRUint too, so could also be something related.

I tried copying over firefox.js from firefox/defaults/pref/ to my fennec/defaults/preferences/mobile.js and this didn't resolve the problem. Next I tried copying over the same file to fennec/xulrunner/defaults/pref/xulrunner.js and this caused the tests to have all kinds of other errors. So I could be doing something wrong, but I don't think the prefs are resolving this issue at hand.

FWIW, a XULRunner build from the Firefox 3.5 Beta 4 release fails very similarly: *** TEST-UNEXPECTED-FAIL | c:\shiretoko\beta4\xu-debug\_tests\xpcshell\test_places\unit\test_frecency.js | http://site.tld/2 == http://site.tld/1 JS frame :: c:\shiretoko\beta4\mozilla-1.9.1\testing\xpcshell\head.js :: do_throw :: line 121 JS frame :: c:\shiretoko\beta4\mozilla-1.9.1\testing\xpcshell\head.js :: do_check_eq :: line 140 JS frame :: c:\shiretoko\beta4\xu-debug\_tests\xpcshell\test_places\unit\test_frecency.js :: anonymous :: line 130 *** FAIL *** Exception: [Exception... "Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIFile.remove]" nsresult: "0x80004005 (NS_ERROR_FAILURE)" location: "JS frame :: c:\shiretoko\beta bookmarks.js :: clearDB :: line 99" data: no] WARNING: nsExceptionService ignoring thread destruction after shutdown: file c:/shiretoko/beta4/mozilla-1.9.1/xpcom/base/nsExceptionService.cpp, WARNING: NS_ENSURE_TRUE(popup != nsnull) failed: file c:/shiretoko/beta4/mozilla-1.9.1/toolkit/components/autocomplete/src/nsAutoCompleteController.cpp, line 1319

Sorry, missed a few key pieces of several lines in comment 6: Exception: [Exception... "Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIFile.remove]" nsresult: "0x80004005 (NS_ERROR_FAILURE)" location: "JS frame :: c:\shiretoko\beta4\xu-debug\_tests\xpcshell\test_places\unit\head_bookmarks.js :: clearDB :: line 99" data: no] WARNING: nsExceptionService ignoring thread destruction after shutdown: file c:/shiretoko/beta4/mozilla-1.9.1/xpcom/base/nsExceptionService.cpp, line 194 WARNING: NS_ENSURE_TRUE(popup != nsnull) failed: file c:/shiretoko/beta4/mozilla-1.9.1/toolkit/components/autocomplete/src/nsAutoCompleteController.cpp, line 1319

This is most likely caused by bug #545747 (I get the same error in test_adaptive.js, and it is fixed by disabling JIT (remove '-j' from the xpcshell options in runxpcshelltests.py))

we don't care about these tests in fennec anymore