Carry over dashboard filters to explore: empty fields transferred

[rumbin]

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• I have checked the superset logs for python stacktraces and included it here as text if any
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Superset version

0.20.3

This issue is addressing the changes introduced by #3461

Expected results

Only currently active dashboard filters are transferred to the explore view and added to the already existing filters of the corresponding slice.

Actual results

Dashboard filters that were previously applied and then dropped again leave empty entries in the URL parameters which are then carried over to the explore view of the slice. This results in filter entries with empty arguments.

Furthermore, any time filters set on the dashboard result in entries in the filter list in explore view with empty column selection.
However, I guess due to #3610, I cannot currently reproduce this behavior. Nevertheless, I wanted you to be aware that this may also happen.

Steps to reproduce

Apply time filters on a dashboard; apply and then drop and other filter and afterwards click Explore chart on any slice.

[Mogball]

Furthermore, any time filters set on the dashboard result in entries in the filter list in explore view with empty column selection.

I cannot seem to reproduce this. I am applying one of each time filter, hitting 'Apply' and then 'explore'.

Can you confirm that this is still an issue/send a screenshot?

[rumbin]

@Mogball No, actually, the time filters are now (0.20.4) carried over nicely, including time column and time grain. So there are no empty filters entries created any more.

However, any column filters that have been previously applied and then cleared again still leave empty fields whern carried over to Explore.