Add disjunction with null condition to isMock constraint #1521
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Description
Added a disjunction with nullability constraint to avoid an assignment to a null object contradicting conditions about whether it is mock or not.
Fixes #1520
Type of Change
How Has This Been Tested?
Regression and integration tests
There is no difference between automatic tests and international tests for the engine.
Automated Testing
org.utbot.examples.mock.CommonMocksExample#mocksForNullOfDifferentTypes
Manual Scenario
Did not check it manually.
Checklist: