For_testing (async_log.async_log.kernel.Async_log_kernel.Global.For

val use_test_output : 
  ?map_output:(string -> string) ->
  ?time:[ `Keep | `Omit ] ->
  ?tags:[ `Keep | `Omit ] ->
  ?level:[ `Keep | `Omit ] ->
  unit ->
  unit

Change the global log so that it 1. Writes synchronously. 2. By default only prints the bodies of messages to stdout, discarding any information about tags, levels, or timestamps. Use optional time, tags and level arguments to print required metadata information.

map_output can be used to transform messages before they make it to stdout; by default it is Fn.id.

(This is equivalent to: Log.Global.set_output [ Log.For_testing.create_output ~map_output ~time ~tags ~level () ])