Mockito remains in unfinished stubbing state if a stubbing fails

[dmitry-timofeev]

If one of doThrow instructions failed due to InstantiationError, Mockito remains in "unfinished stubbing" state and can no longer mock anything.

I had this issue in a single JUnit 4 test, but the fact that Mockito remained in "unfinished stubbing" state used to result in all tests being marked as failed (I couldn't reproduce the last effect with the latest Mockito neither in JUnit 4 nor with JUnit 5 now, so the issue is applicable to a single test invocation only).

import java.util.List;
import org.junit.jupiter.api.RepeatedTest;
import org.junit.jupiter.api.RepetitionInfo;
import org.mockito.Mockito;

class UninstantiableTest {

  @RepeatedTest(2)
  void tryThrow01(RepetitionInfo i) {
    if (i.getCurrentRepetition() == 1) {
      // Stub using uninstantiable exception.
      try {
        List mock = Mockito.mock(List.class);

        Mockito.doThrow(UninstantiableException.class).when(mock).clear();
      } catch (InstantiationError expected) {
        // Get a j.l.InstantiationError.
      }
    }

    // Try to stub another mock, this time using a valid exception type.
    {
      List mock = Mockito.mock(List.class);

      // The following operation results in "UnfinishedStubbing"
      Mockito.doThrow(RuntimeException.class).when(mock).clear();
    }
  }

  abstract static class UninstantiableException extends RuntimeException {}
}

Mockito version 2.23.0

check that

• The mockito message in the stacktrace have useful information, but it didn't help
• The problematic code (if that's possible) is copied here;
  Note that some configuration are impossible to mock via Mockito
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• Provide a Short, Self Contained, Correct (Compilable), Example of the issue
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[dmitry-timofeev]

A fix (if this is an issue) might be simple:

Index: src/main/java/org/mockito/internal/stubbing/StubberImpl.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- src/main/java/org/mockito/internal/stubbing/StubberImpl.java	(revision 11e28796ecd89470ca50632e0fe9b2e4260e323a)
+++ src/main/java/org/mockito/internal/stubbing/StubberImpl.java	(date 1532965613000)
@@ -93,6 +93,9 @@
         } catch (RuntimeException instantiationError) {
             mockingProgress().reset();
             throw instantiationError;
+        } catch (InstantiationError instantiationError) {
+            mockingProgress().reset();
+            throw instantiationError;
         }
         return doThrow(e);
     }

[mockitoguy]

@dmitry-timofeev, do you want to take a stab at it? Please provide top level test that demonstrates the problem, too. It would be really helpful. Thank you!

[dmitry-timofeev]

Hi @mockitoguy , thank you for having a look. I'm a little busy at work, therefore I won't be able to in the coming weeks.

[mockitoguy]

That's fair, we will try find time to work on this. Thank you for reporting!