TimeControl

Enables virtual time control for the duration of the block.

Intercepts sleep, select ... when timeout(...), Time.utc, and Time.instant so that time stands still until explicitly advanced via Controller#advance.

IO operation timeouts (e.g. read_timeout, write_timeout) are also intercepted on builds that use the Polling event loop (kqueue on macOS/BSD, epoll on Linux). They are not intercepted on LibEvent or IOCP builds.

An optional start_time sets the initial value of Time.utc inside the block. Without it, virtual UTC starts at the real wall-clock time.

TimeControl.control do |controller|
  spawn { sleep 5.minutes; puts "done" }
  controller.advance(5.minutes)
end

TimeControl.control(Time.utc(2030, 1, 1)) do |controller|
  Time.utc.year # => 2030
end

TimeControl.control("2030-01-01T09:00:00Z") do |controller|
  Time.utc.hour # => 9
end