Re: [Monotone-debian] monotone-viz

[Francis Russell]

Ludovic Brenta wrote:

> Sorry for the delay, real life caught on.

I completely understand.

> I finally reviewed your
> changes and I have to say I'm impressed with your attention to detail.

Thanks :)

> One thing caught my eye though: in patches/20-dot-rankdir.diff, I see
> 
> -    then [ "/bin/sh" ; "-c" ;
> +    then [ "/bin/bash" ; "-c" ;
> 
> which is probably because the shell command contains bashisms.
> Unfortunately, this makes monotone-viz depend on bash; bash is no longer
> the default shell and, although I've only ever used bash myself, I know
> people who prefer zsh and don't have or want bash on their systems.

I noticed that too and queried it when Thomas Moschny posted the patch
to the monotone-devel mailing list. His response was:

"The shell is only used in debug mode ('if Viz_misc.debug "dot"').
Otherwise, dot is called directly. And the 'pipefail' option is
probably not supported by (any) sh, but it is by bash."

The bash pipefail option will make the return value of a pipeline the
value of the rightmost command with a non-zero exit status which I guess
 is useful for debugging.


> So, could you please see if you can remove the bashism or, failing that,
> add an explicit dependency on bash in the control file?

It seems as though bash won't be called unless montone-viz is run in
debug mode. I couldn't find any obvious way to enable it from the
command-line or the UI so I guess a normal user will never use it.
It also seems likely that patch will be committed upstream and I don't
see much reason to diverge from that by removing the bashism.

As for the bash dependency, Debian already defines bash as an essential
package. According to Debian policy, packages don't need to declare
dependencies on essential packages and even recommends against it. I
think we're safe :)

Francis