Job submission failing in JUnit tests

java.lang.IllegalStateException: Variable substitution depth too large: 20 ${fs.default.name}
        at org.apache.hadoop.conf.Configuration.substituteVars(Configuration.java:551)
        at org.apache.hadoop.conf.Configuration.get(Configuration.java:569)
        at org.apache.hadoop.conf.Configuration.getStrings(Configuration.java:1020)
        at org.apache.hadoop.mapreduce.JobSubmitter.populateTokenCache(JobSubmitter.java:564)
        at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:353)
        at org.apache.hadoop.mapreduce.Job$2.run(Job.java:1159)
        at org.apache.hadoop.mapreduce.Job$2.run(Job.java:1156)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:396)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1152)
        at org.apache.hadoop.mapreduce.Job.submit(Job.java:1156)
        at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:1176)
        at org.apache.hadoop.mapred.gridmix.Gridmix.launchGridmixJob(Gridmix.java:190)
        at org.apache.hadoop.mapred.gridmix.Gridmix.writeInputData(Gridmix.java:150)
        at org.apache.hadoop.mapred.gridmix.Gridmix.start(Gridmix.java:425)
        at org.apache.hadoop.mapred.gridmix.Gridmix.runJob(Gridmix.java:380)
        at org.apache.hadoop.mapred.gridmix.Gridmix.access$000(Gridmix.java:56)
        at org.apache.hadoop.mapred.gridmix.Gridmix$1.run(Gridmix.java:313)
        at org.apache.hadoop.mapred.gridmix.Gridmix$1.run(Gridmix.java:311)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:396)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1152)
        at org.apache.hadoop.mapred.gridmix.Gridmix.run(Gridmix.java:311)