Maven test fails to run moco server when using jacoco maven plugin 0.7.8 or newer

[chenhengjie123]

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Also check FAQ before opening an issue: http://www.jacoco.org/jacoco/trunk/doc/faq.html

Steps to reproduce

test case code:

import com.github.dreamhead.moco.Moco;
import com.github.dreamhead.moco.junit.MocoJunitRunner;
import org.apache.http.HttpResponse;
import org.apache.http.client.fluent.Request;
import org.junit.Rule;
import org.junit.Test;
import org.junit.runner.RunWith;

import java.io.IOException;

public class BzdWithdrawHisServiceImplTest {
    @Rule
    public MocoJunitRunner runner = MocoJunitRunner.jsonHttpRunner(12306, Moco.pathResource("foo.json"));

    @Test
    public void  mockTest() throws IOException {
        HttpResponse httpResponse = Request.Get("http://localhost:12306").execute().returnResponse();
        System.out.println(httpResponse);
    }
}

configuration in pom.xml:

...
        <!-- https://mvnrepository.com/artifact/com.github.dreamhead/moco-junit -->
        <dependency>
            <groupId>com.github.dreamhead</groupId>
            <artifactId>moco-junit</artifactId>
            <version>0.12.0</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/com.github.dreamhead/moco-runner -->
        <dependency>
            <groupId>com.github.dreamhead</groupId>
            <artifactId>moco-runner</artifactId>
            <version>0.12.0</version>
        </dependency>
...
            <plugin>
                <groupId>org.jacoco</groupId>
                <artifactId>jacoco-maven-plugin</artifactId>
                <version>${jacoco.maven.plugin.version}</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>prepare-agent</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>report</id>
                        <phase>prepare-package</phase>
                        <goals>
                            <goal>report</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>

error occurs when running mvn test to run tests with jacoco.

JaCoCo version: multiple, mentioned in Actual behaviour
Operating system: occurs on mac os 10.14 and windows 7
Tool integration: Maven/Ant/API/Other: maven

Expected behaviour

mvn test could run well

Actual behaviour

when running mvn test, error occurs like below:

Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 2.355 sec <<< FAILURE! - in com.ppmoney.feastful.fc.BzdWithdrawHisServiceImplTest
mockTest(com.ppmoney.feastful.fc.BzdWithdrawHisServiceImplTest)  Time elapsed: 0.012 sec  <<< ERROR!
java.lang.IllegalArgumentException: unknown field [$jacocoData]
	at com.ppmoney.feastful.fc.BzdWithdrawHisServiceImplTest.<init>(BzdWithdrawHisServiceImplTest.java:15)

jacoco maven plugin version	result
0.7.2.201409121644	success
0.7.7.201606060606	success
0.7.8	error
0.8.2	error

[Godin]

@chenhengjie123 the list of dependencies is definitely incomplete:

BzdWithdrawHisServiceImplTest.java:[4,37] package org.apache.http.client.fluent does not exist

So could you please attach zip with complete example without ... ?

[chenhengjie123]

@chenhengjie123 the list of dependencies is definitely incomplete:

BzdWithdrawHisServiceImplTest.java:[4,37] package org.apache.http.client.fluent does not exist

So could you please attach zip with complete example without ... ?

I have just uploaded the simplest project on https://github.com/chenhengjie123/ReproduceJacocoWithMoco. It can reproduce this issue.

[Godin]

And it shows different stack trace:

java.lang.IllegalArgumentException: unknown field [$jacocoData]
        at com.github.dreamhead.moco.parser.model.DynamicResponseHandlerFactory.createResponseHandler(DynamicResponseHandlerFactory.java:116)
        at com.github.dreamhead.moco.parser.model.DynamicResponseHandlerFactory.access$000(DynamicResponseHandlerFactory.java:37)
        at com.github.dreamhead.moco.parser.model.DynamicResponseHandlerFactory$1.apply(DynamicResponseHandlerFactory.java:70)
        at com.github.dreamhead.moco.parser.model.DynamicResponseHandlerFactory$1.apply(DynamicResponseHandlerFactory.java:65)
        at com.google.common.collect.Iterators$7.transform(Iterators.java:750)
        at com.google.common.collect.TransformedIterator.next(TransformedIterator.java:47)
        at com.google.common.collect.Iterators.size(Iterators.java:198)
        at com.google.common.collect.Iterables.size(Iterables.java:106)
        at com.google.common.collect.FluentIterable.size(FluentIterable.java:342)
        at com.github.dreamhead.moco.parser.model.DynamicResponseHandlerFactory.getResponseHandler(DynamicResponseHandlerFactory.java:53)
        at com.github.dreamhead.moco.parser.model.DynamicResponseHandlerFactory.createResponseHandler(DynamicResponseHandlerFactory.java:49)
        at com.github.dreamhead.moco.parser.model.ResponseSetting.getResponseHandler(ResponseSetting.java:62)
        at com.github.dreamhead.moco.parser.model.SessionSetting.getResponseHandler(SessionSetting.java:66)
        at com.github.dreamhead.moco.parser.model.SessionSetting.bindToSession(SessionSetting.java:111)
        at com.github.dreamhead.moco.parser.model.SessionSetting.bindTo(SessionSetting.java:78)
        at com.github.dreamhead.moco.parser.model.SessionSetting.newHttpServer(SessionSetting.java:144)
        at com.github.dreamhead.moco.parser.HttpServerParser.createServer(HttpServerParser.java:23)
        at com.github.dreamhead.moco.parser.HttpServerParser.createServer(HttpServerParser.java:12)
        at com.github.dreamhead.moco.parser.BaseParser.parseServer(BaseParser.java:19)
        at com.github.dreamhead.moco.MocoJsonRunner.parseHttpServer(MocoJsonRunner.java:60)
        at com.github.dreamhead.moco.MocoJsonRunner.jsonHttpServer(MocoJsonRunner.java:21)
        at com.github.dreamhead.moco.junit.MocoJunitRunner.jsonHttpRunner(MocoJunitRunner.java:37)
        at demo.TestForReproduceMocoWithJacoco.<init>(TestForReproduceMocoWithJacoco.java:14)

whose most relevant part is - DynamicResponseHandlerFactory.java:49, three lines above there is call of getFields and two lines above there is call of isValidFilter that filters final fields, but doesn't not filter out synthetic fields, whereas should - please read https://www.jacoco.org/jacoco/trunk/doc/faq.html :

My code uses reflection. Why does it fail when I execute it with JaCoCo?

To collect execution data JaCoCo instruments the classes under test which adds two members to the classes: A private static field $jacocoData and a private static method $jacocoInit(). Both members are marked as synthetic.

Please change your code to ignore synthetic members. This is a good practice anyways as also the Java compiler creates synthetic members in certain situation.

JaCoCo <=0.7.7 works, because in addition to field being synthetic, it was also incorrectly always final - see #434 that was fixed in 0.7.8.

---

As a workaround seems possible to exclude classes from instrumentation as following:

                 <execution>
                     <goals>
                         <goal>prepare-agent</goal>
                     </goals>
+                    <configuration>
+                        <excludes>com/github/dreamhead/moco/*</excludes>
+                    </configuration>
                 </execution>

with and without update to latest

-        <jacoco.maven.plugin.version>0.7.8</jacoco.maven.plugin.version>
+        <jacoco.maven.plugin.version>0.8.2</jacoco.maven.plugin.version>

[chenhengjie123]

OK，I got it. The trace is different maybe cause by the origin project has other configs. Since it's a company project, I could not share the whole project, so I create this new project instead.

Thanks a lot!