addition to fix #141

[FabiKo117]

Description

replace null with empty enum set
addition to fix in pr #144 (issue #141)

Checklist

• My code follows the code-style rules, and I have checked on the static analyses
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• I have added sufficient unit and API tests
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[FabiKo117]

@rtroilo do we still want to maybe add a unit test regarding this issue? The thing is, if it should be an integration test, like most of the others, we'd have to find that problem within the Heidelberg.oshdb dataset, as that's the one used in our test environment.

[joker234]

@rtroilo do we still want to maybe add a unit test regarding this issue? The thing is, if it should be an integration test, like most of the others, we'd have to find that problem within the Heidelberg.oshdb dataset, as that's the one used in our test environment.

that would be very very cool, indeed :)

[tyrasd]

@rtroilo do we still want to maybe add a unit test regarding this issue? The thing is, if it should be an integration test, like most of the others, we'd have to find that problem within the Heidelberg.oshdb dataset, as that's the one used in our test environment.

that would be very very cool, indeed :)

So, we're looking for elements which are unchanged in the time interval of the query which have an empty geometry, so that they trigger the NPE at createOSMFeature(ExecutionUtils.java:387)? The first condition might be easy to trigger since we can control the time interval of the test query, but not sure about the second one. Do you know which element(s) triggered the bug when you first encountered it?

[tyrasd]

So, we're looking for elements which are unchanged in the time interval of the query which have an empty geometry, so that they trigger the NPE at createOSMFeature(ExecutionUtils.java:387)?

I tried for a bit, but could not find any quick way to reproduce the bug with elements in the test data set. 😒 maybe we can go ahead without a test for this specific bug?