Pipeline with single "forward" module crashes

What steps will reproduce the problem?
1. Create a file 'test.groovy' with this content:
 transfer = {
   doc title: "Simply transfers files to the next stage, untouched"
   println("inputs are " + inputs)
   forward inputs
 }

 Bpipe.run {
   transfer
 }

2. Run: bpipe run test.groovy test.groovy

What is the expected output? What do you see instead?
Bpipe should successfully complete. Instead, this error message is reported:
 inputs are test.groovy
 java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at org.codehaus.groovy.tools.GroovyStarter.rootLoader(GroovyStarter.java:106)
    at org.codehaus.groovy.tools.GroovyStarter.main(GroovyStarter.java:128)
Caused by: groovy.lang.MissingFieldException: No such field: input for class: 
bpipe.MultiPipelineInput
    at groovy.lang.MetaClassImpl.getAttribute(MetaClassImpl.java:2577)
    at groovy.lang.MetaClassImpl.getAttribute(MetaClassImpl.java:3416)
    at org.codehaus.groovy.runtime.InvokerHelper.getAttribute(InvokerHelper.java:142)
    at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.getField(ScriptBytecodeAdapter.java:302)
    at bpipe.PipelineContext.forward(PipelineContext.groovy:1636)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

What version of the product are you using? On what operating system?
Bpipe 0.9.8.5 on Linux x86_64

Original issue reported on code.google.com by florent....@gmail.com on 17 Mar 2014 at 5:25

pallassgj / bpipe

Pipeline with single "forward" module crashes #89