Test library failed to export after import

[Shrhawk]

TNL-2686

Test for Xblock pr#305 where while setting xml attribute with None value throwing TypeError , solve this by adding an inline check if value is of None Type return empty string to save xml attribute

[Shrhawk]

@adampalay @awais786 this is failing test

[Shrhawk]

@muhammad-ammar @adampalay @awaisdar001

[adampalay]

why put this in a try/except?

[Shrhawk]

because we have to clean the temp directory if any Exception occurs

[adampalay]

do try/finally then

[Shrhawk]

i am using the same directory for export below so add the finally block L#468 for export_library_to_xml

[adampalay]

I don't know if it's a risk if the test fails and the extract_dir isn't cleared because we do a git clean before running the tests. If you want to be careful, wrap the whole test in a try/finally.

[Shrhawk]

@adampalay review it

[adampalay]

you don't need a try/except here. If there's no error, then the test passes. If there is an error, the test will automatically not pass.

[Shrhawk]

@adampalay

[adampalay]

you don't need this line or L469

[adampalay]

Once the XBlock change is merged to master, and this PR changes the xblock hash to XBlock master, 👍

[Shrhawk]

@adampalay review it.

[adampalay]

👍

[Shrhawk]

@cpennington , @muzaffaryousaf review it.

[Shrhawk]

@doctoryes kindly review it .

[doctoryes]

Does this mean that advertised_start should be set to '' everywhere that it's currently set to None? A recent change added this line:

https://github.com/edx/edx-platform/blob/master/cms/djangoapps/contentstore/views/course.py#L790

[Shrhawk]

yes and thanks for the catching this

[Shrhawk]

@doctoryes done the changes have a look

[doctoryes]

👍

[adampalay]

@Shrhawk , you need to merge https://github.com/edx/XBlock/pull/305 and then update the xblock hash here before you merge this PR