Why are test dependencies added to runtime dependencies

[John Shahid]

Hey all,

I came across lines 174-177 in lib/buildr/run.rb
    after_define(:run => :test) do |project|
      project.run.with project.test.compile.dependencies
      project.run.with project.test.compile.target if 
project.test.compile.target
    end

My question is why are the dependencies used in compiling the tests 
added to the run task ?