Flakiness in running tests under Maven

[msridhar]

When running mvn clean verify after a fresh checkout, the WALA core tests fail to run, with the following error:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:2.14.1:test (test) on project com.ibm.wala.core.tests: Execution test of goal org.apache.maven.plugins:maven-surefire-plugin:2.14.1:test failed: There was an error in the forked process
[ERROR] java.lang.NoClassDefFoundError: com/ibm/wala/util/graph/NumberedGraph
[ERROR] at java.lang.Class.getDeclaredMethods0(Native Method)
[ERROR] at java.lang.Class.privateGetDeclaredMethods(Class.java:2451)
[ERROR] at java.lang.Class.getMethod0(Class.java:2694)
[ERROR] at java.lang.Class.getMethod(Class.java:1622)
[ERROR] at org.apache.maven.surefire.util.ReflectionUtils.tryGetMethod(ReflectionUtils.java:57)
[ERROR] at org.apache.maven.surefire.common.junit3.JUnit3TestChecker.isSuiteOnly(JUnit3TestChecker.java:64)
[ERROR] at org.apache.maven.surefire.common.junit3.JUnit3TestChecker.isValidJUnit3Test(JUnit3TestChecker.java:59)
[ERROR] at org.apache.maven.surefire.common.junit3.JUnit3TestChecker.accept(JUnit3TestChecker.java:54)
[ERROR] at org.apache.maven.surefire.common.junit4.JUnit4TestChecker.accept(JUnit4TestChecker.java:51)
[ERROR] at org.apache.maven.surefire.util.DefaultScanResult.applyFilter(DefaultScanResult.java:97)
[ERROR] at org.apache.maven.surefire.junit4.JUnit4Provider.scanClassPath(JUnit4Provider.java:206)
[ERROR] at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:103)
[ERROR] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[ERROR] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
[ERROR] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
[ERROR] at java.lang.reflect.Method.invoke(Method.java:601)
[ERROR] at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray2(ReflectionUtils.java:208)

However, if we run mvn clean verify -DskipTests=true, and then run mvn clean verify, the tests run fine and pass. We should probably figure out what's going on here.

[msridhar]

Not going to worry about these Maven issues anymore