Debugging restore_ports.tcl

[Eric Gallager]

On Tue, Feb 9, 2021 at 6:23 AM Pieter van Oostrum
<pieter-l at vanoostrum.org> wrote:
>
> Eric Gallager via macports-users <macports-users at lists.macports.org> writes:
>
> > On Mon, Feb 8, 2021 at 1:03 PM Ryan Schmidt <ryandesign at macports.org> wrote:
> >>
> >>
> >>
> >> On Feb 7, 2021, at 20:59, Eric Gallager wrote:
> >>
> >> > When restore_ports.tcl gets stuck building its list of ports to
> >> > restore, is there a way to get it to tell you which ports exactly it's
> >> > failing to process? i.e., which ports to remove from your myports.txt
> >> > to get it to continue?
> >>
> >> I don't know. In what way is it getting stuck?
> >
> > It's the part on the Troubleshooting section of the wiki page where it says:
> >
> > If you see an "infinite loop" error message, such as this:
> >
> > Error: we appear to be stuck, exiting...
> > infinite loop
> >     while executing
> > "sort_ports $portList"
> >     invoked from within
> > "set operationList [sort_ports $portList]"
> >     (file "./restore_ports.tcl" line 285)
> >
> > it indicates that the script has a list of ports to install, and it
> > can't figure out which of the ports to install next.
> >
> > https://trac.macports.org/wiki/Migration#Troubleshooting
> >
> > The workaround it suggests to deal with this issue is "to reduce your
> > list of ports to install, until it no longer has a dependency cycle,"
> > but it doesn't say exactly HOW to go about choosing which ports to
> > remove from the list in order to reduce its length.
> > My myports.txt file has 6147 lines in it. I don't know where to begin with it.
>
> The usual way of tackling these kinds of problems is "bisecting". Divide the list in two halves, and try each of these separately. If a half fails, then divide it in two halves again, etc.

With git at least, there's a built-in command (`git bisect`) to assist
with cases like this; would it be possible to add a similar feature to
the restore_ports.tcl script?

> --
> Pieter van Oostrum
> www: http://pieter.vanoostrum.org/
> PGP key: [8DAE142BE17999C4]