Re: keep spinning even without new line

[Ricardo Wurmus <rekado@elephly.net>]

Ricardo Wurmus <rekado@elephly.net> writes:

> Hi Guix,
>
> when using “guix package -i” the build log lines are replaced with a
> spinner character.  In some cases, the build log does not produce new
> lines for a long time, so that the spinner appears to be stuck.
>
> What do you think of advancing the spinner even when the build log is
> not verbose enough to trigger the display of the next character?  How
> can this be accomplished?

One way to accomplish this is to generate periodic “(build-log
heartbeat)” events, so that “print-build-event” in (guix status) only
needs to advance the spinner when the last event was a build-log event.

Currently, events are produced only by “build-event-output-port”, which
generates them when processing build trace strings sent by the daemon.
I don’t really want to change the daemon to intersperse the actual build
output with heartbeat traces, so maybe a timer should generate these
events in “build-event-output-port” or even earlier in “process-stderr”.

“process-stderr” is probably too low-level, and there’s a chance that
injecting output there would corrupt the output sent by the daemon.

Any better ideas?

--
Ricardo