ByteBuddy reset fails when running with Eclipse (EclEmma/JaCoCo) Code Coverage

Question

I am redefining classes with ByteBuddy within a unit test. I am resetting the class after each test to ensure no cross-talk between tests.

ByteBuddy works as expected when simply running the tests in the Eclipse IDE or when running with maven command line. But if it run in Eclipse with coverage, resetting the class results in the following exception:

java.lang.UnsupportedOperationException: class redefinition failed: attempted to change the schema (add/remove fields)

Bellow is a sample test which passes in the default JUnit runner but fails when run with Code Coverage in Eclipse. Below that is the full stack trace of the failure.

I am using ByteBuddy version 1.8.22 and the EclEmma Java Code Coverage Package version 3.1.0.201804041601.

I am assuming this issue is due to a conflict between ByteBuddy class modifications and EclEmma code instrumentation. It there an alternate approach to restoring class definitions that would work around this issue?

Fails under Coverage:

import static net.bytebuddy.matcher.ElementMatchers.named;
import static org.assertj.core.api.Assertions.assertThat;

import org.junit.Test;

import net.bytebuddy.ByteBuddy;
import net.bytebuddy.agent.ByteBuddyAgent;
import net.bytebuddy.dynamic.loading.ClassReloadingStrategy;
import net.bytebuddy.implementation.FixedValue;

public class ByteBuddyEclEmmaTest {

    @Test
    public void recreateEclEmmaByteBuddyResetIssue() throws Exception {

        ByteBuddyAgent.install();

        ByteBuddy byteBuddy = new ByteBuddy();
        ClassReloadingStrategy classReloadingStrategy = ClassReloadingStrategy.fromInstalledAgent();

        byteBuddy
                .redefine(X.class)
                .method(named("getValue")).intercept(FixedValue.value("faked value"))
                .make()
                .load(X.class.getClassLoader(), classReloadingStrategy);

        X x = new X();
        assertThat(x.getValue()).isEqualTo("faked value");

        classReloadingStrategy.reset(X.class);

        assertThat(x.getValue()).isEqualTo("real value");
    }

    public class X {

        public String getValue() {

            return "real value";
        }
    }
}

Stack Trace:

java.lang.UnsupportedOperationException: class redefinition failed: attempted to change the schema (add/remove fields)
    at sun.instrument.InstrumentationImpl.redefineClasses0(Native Method)
    at sun.instrument.InstrumentationImpl.redefineClasses(InstrumentationImpl.java:170)
    at net.bytebuddy.dynamic.loading.ClassReloadingStrategy$Strategy$1.apply(ClassReloadingStrategy.java:261)
    at net.bytebuddy.dynamic.loading.ClassReloadingStrategy$Strategy$1.reset(ClassReloadingStrategy.java:279)
    at net.bytebuddy.dynamic.loading.ClassReloadingStrategy.reset(ClassReloadingStrategy.java:209)
    at net.bytebuddy.dynamic.loading.ClassReloadingStrategy.reset(ClassReloadingStrategy.java:195)
    at ByteBuddyEclEmmaTest.recreateEclEmmaByteBuddyResetIssue(ByteBuddyEclEmmaTest.java:30)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206)

Answer 1

I figured out my issue was caused by an older version of ByteBuddy. I was getting version 1.6.14 pulled into my project from Mockito. When I explicitly brought in ByteBuddy version 1.8.22, the test runs successfully, both with and without Coverage.