deployInternal() in ArchiveDeployer (from arquillian/) walks back along the chain of initialCause exceptions to attach the root cause to the thrown exception, presumably in an attempt to reduce the clutter in the output.

The way it does so is incorrect and will always result in rootCause=null. I think that it should just attach "ex" as-is, but if stripping the intermediate exceptions is what is desired, then the while condition should be "rootCause != null && rootCause.getCause() != null", so that it extracts the last one.

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Throwable rootCause = ex.getCause();
while (null != rootCause)

throw new DeploymentException("Cannot deploy: " + name, rootCause);
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