in lib/skywalking/span.lua [108:127]
function _M.new(operationName, context, parent)
local span = _M.newNoOP()
span.is_noop = false
span.operation_name = operationName
span.span_id = context.internal.nextSpanID(context.internal)
if parent == nil then
span.parent_span_id = -1
else
span.parent_span_id = parent.span_id
end
context.internal.addActive(context.internal, span)
span.refs = {}
span.owner = context
return span
end