Bugzilla Bug 186945

I love the new revdep-rebuild.  It's awesome.  However, the [X%] progress bar
thing flickers horribly.  It's easy enough to fix -- just add code to only
print when something has changed.  I will attach a patch to this bug report.

Reproducible: Always

Steps to Reproduce:
1. Run revdep-rebuild without the -quiet flag.
2. Freeze in horror as the flickering progress bar gives you a headache. 
3. Run screaming from the keyboard.

Actual Results:  
Progress bar flickers.

Expected Results:  
Progress bar updates only when the percentage is different from before.

Created an attachment (id=126280) [edit]
Patch to remove flicker from the progress meter

As promised, here's a patch to /usr/bin/revdep-rebuild.

I put my complain in here, since it's similar bug, and to avoid creation of new
one: I use revdep in cron. Cron mails me the result. It is usually very long
since it mails me the compile log as side effect. But, see what happens:
(this took 3/4 of the "visible hight of the mail" (not weight, but height):

 * Checking dynamic linking consistency


[ 0% ] 

[ 0% ] 

[ 0% ] 
[...]
[ 99% ] 

[ 99% ] 

[ 100% ] 
 *   broken /opt/sun-jdk-1.4.2.15/jre/lib/i386/libnio.so (no version
information available)
 * Generated new //.revdep-rebuild.3_rebuild

This has a very simple workaroung: do not use progress bar at all when the
output is not a console (I have seen this feature some where, may be emerge: no
progress bar or spinning bar when used like
emerge -va foo |grep -v bar
(outputs everything except "bar" => no spinning cursor).

You will find there the code to implement it ^^

Robert, maybe it flickers because it is synchronised with your screen refresh
^^ LCD is a solution.

(In reply to comment #3)
> Robert, maybe it flickers because it is synchronised with your screen refresh
> ^^ LCD is a solution.
> 

Thanks for the suggestion DeMaine, but as it turns out -- I only use LCD.  The
problem is simply that the progress bar gets draw multiple times when it does
not need to.  The patch I attached ought to solve the problem.  Also, have you
tried using the "-quiet" flag when running from your cron job?  Does that get
rid of the extra output in your logs?

I tell you next week.

Use --quiet to prevent the progress bar in scripts and cron jobs.

Created an attachment (id=127278) [edit]
revdep-rebuild-rewrite.patch

Patch against the latest SVN version of *-rewrite. This patch also includes the
fix to using ewarn before sourcing /etc/functions.sh.

As for the progress() fix, It's the same idea as Robert's, just rewritten so it
patches cleanly.

Thanks, Robert!

$ svn commit -m "Fix progress bar to only update when there is a change (Bug
#186945)"
Sending        ChangeLog
Sending        src/revdep-rebuild/revdep-rebuild-rewrite
Transmitting file data ..
Committed revision 431.

Released in gentoolkit-0.2.4_pre7