1103159 - UnboundLocalError: local variable 'result' referenced before assignment with --e10s and --total-chunks

Status: RESOLVED FIXED

(Testing :: Mochitest, defect)

Description

[Andrew McCreight [:mccr8]]

Running this:
  ./mach mochitest-browser --e10s --total-chunks 10 --this-chunk 10
Gives me this:
From _tests: Kept 33741 existing; Added/updated 0; Removed 0 files and 0 directories.
TEST-INFO | checking window state
Browser Chrome Test Summary
	Passed: 0
	Failed: 0
	Todo: 0
*** End BrowserChrome Test Results ***
Error running mach:

    ['mochitest-browser', '--e10s', '--total-chunks', '10', '--this-chunk', '10']

The error occurred in code that was called by the mach command. This is either
a bug in the called code itself or in the way that mach is calling it.

You should consider filing a bug for this issue.

If filing a bug, please include the full output of mach, including this error
message.

The details of the failure are as follows:

UnboundLocalError: local variable 'result' referenced before assignment

  File "/home/amccreight/mc/testing/mochitest/mach_commands.py", line 662, in run_mochitest_browser
    return self.run_mochitest(test_paths, 'browser', **kwargs)
  File "/home/amccreight/mc/testing/mochitest/mach_commands.py", line 785, in run_mochitest
    test_paths=test_paths, suite=flavor, **kwargs)
  File "/home/amccreight/mc/testing/mochitest/mach_commands.py", line 390, in run_desktop_test
    result = runner.runTests(options)
  File "/home/amccreight/mc/obj-dbg/_tests/testing/mochitest/runtests.py", line 1764, in runTests
    return result

Removing the two chunk arguments, or the --e10s, makes the error go away.

Comment 1

[Andrew McCreight [:mccr8]]

This looks like it may have broken in bug 1036374, which added the |return result| without defining result on all return paths.

Comment 2

[Andrew McCreight [:mccr8]]

It works fine with total-chunks=3, so maybe the problem is that with total-chunks=10 the set of directories is empty?

Comment 3

[Joel Maher ( :jmaher ) (UTC -8)]

ahh, most likely that is the case!  I suspect we can make a better error for the case when there are no chunks.

Comment 4

[Chris Peterson [:cpeterson]]

e10s test

Comment 5

[Tim Taubert [:ttaubert] (inactive)]

Not being able to run e10s tests locally is quite bad.

Comment 6

[Andrew McCreight [:mccr8]]

I was able to run them, it was just that the final chunk was empty in some cases and I got this weird message.

Comment 7

[Vaibhav (:vaibhav1994)]

Attachment: bug1103159.patch

This patch will ensure that the directories being run is non-empty and then only return the result parameter, thus not giving rise to this error.

Comment 8

[Joel Maher ( :jmaher ) (UTC -8)]

Comment on attachment 8539450 [details] [diff] [review]
bug1103159.patch

Review of attachment 8539450 [details] [diff] [review]:
-----------------------------------------------------------------

Please make this return a value:
0 = green
1 = orange

since there are no tests run, this probably should be a value of 1

::: testing/mochitest/runtests.py
@@ +1786,5 @@
>        print "3 INFO Todo:    %s" % self.counttodo
>        print "4 INFO SimpleTest FINISHED"
>  
> +    if dirs:
> +        return result

I would rather set result to a default value and always return something.  We use the return code from here when we sys.ext()

Comment 9

[Vaibhav (:vaibhav1994)]

Attachment: bug1103159.patch

Placed a default value for result variable.

Comment 10

[Joel Maher ( :jmaher ) (UTC -8)]

Comment on attachment 8539467 [details] [diff] [review]
bug1103159.patch

Review of attachment 8539467 [details] [diff] [review]:
-----------------------------------------------------------------

thanks, how does this look locally.  Make sure whilst running this locally and hitting this condition that the ./mach termination makes sense.

Comment 11

[Vaibhav (:vaibhav1994)]

vaibhav@vaibhav:~/mozilla-inbound$ ./mach mochitest-browser --e10s --total-chunks 10 --this-chunk 10
Build configuration changed. Regenerating backend.
Reticulating splines...
Finished reading 2748 moz.build files in 2.13s
Processed into 7569 build config descriptors in 1.71s
Backend executed in 2.74s
2265 total backend files; 0 created; 1 updated; 2264 unchanged; 0 deleted; 139 -> 852 Makefile
Total wall time: 6.86s; CPU time: 6.41s; Efficiency: 93%; Untracked: 0.29s
From _tests: Kept 34202 existing; Added/updated 0; Removed 0 files and 0 directories.
TEST-INFO | checking window state
Browser Chrome Test Summary
	Passed: 0
	Failed: 0
	Todo: 0
*** End BrowserChrome Test Results ***
0 ERROR Got suite_end message before suite_start.


This is the output. It shows that 0 tests are run. The last error is occurring because of 
bug 1060439.

Comment 12

[Joel Maher ( :jmaher ) (UTC -8)]

this looks great, thanks!

Comment 13

[Vaibhav (:vaibhav1994)]

Try push: https://treeherder.mozilla.org/ui/#/jobs?repo=try&revision=17d5b78fe521

Comment 14

[Vaibhav (:vaibhav1994)]

The try run is green as expected.

Comment 15

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/c3f9a03e9745

Comment 16

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/c3f9a03e9745