class HTTP::Request::Body::ProcIO

“destination IO” in IO.copy_stream.
#write simply calling the proc, which we can pass in as the
This class provides a “writable IO” wrapper around a proc object, with

def initialize(block)

def initialize(block)
  @block = block
end

def write(data)

def write(data)
  @block.call(data)
  data.bytesize
end