[Feature request] CLI option to check the reverse dependencies of the (current/specified/changed) packages.

[kentfredric]

This is very helpful to do when doing keywording work. You don't want to have to scan the whole tree just to find revdeps with keyword problems.

And I've found a neat hack that does 95% of the work without any of the performance problems.

#!perl
use strict;
use warnings;

use constant root      => "/usr/local/gentoo";
use constant http_root => "https://qa-reports.gentoo.org/output/genrdeps/";

my $client = do {
    require HTTP::Tiny;
    HTTP::Tiny->new();
};

my ( $package, $match ) = @ARGV;

my $deps = {};
for my $grade ( 'rindex', 'dindex', 'pindex', 'bindex' ) {
    my $result = $client->get( http_root . $grade . '/' . $package );
    if ( $result->{success} ) {
      for my $line ( split qr/\n/, $result->{content} ) {
        my $data = {
          in => $grade,
          statement => $line,
        };
        if ( $line =~ s/:([^:]+)$// ) {
          $data->{use} = $1;
        }
        $deps->{$line} ||=[];
        push @{$deps->{$line}}, $data;
      }
    }
}
my %categories;
for my $dep ( sort keys %{$deps} ) {
  my $package = get_package($dep);
  my ( $category, $pn ) = split q[/], $package;
  $categories{$category}{$pn}++;
}
for my $category ( sort keys %categories ) {
  chdir root . $category;
  print "\e[31m> $category\e[0m\n";
  printf "\e[31m  %s\e[0m\n", join q[, ], sort keys %{$categories{$category}};
  system('pkgcheck', 'scan','-v', '-s=-profiles', sort keys %{$categories{$category}} ) == 0
    or die;

}

sub get_package {
  my ( $atom ) = @_;
  open my $fh, '-|', 'qatom', '-F', "%{CATEGORY}/%{PN}", $atom or die "Can't invoke qatom";
  my $content = do {
    local $/ = undef;
    <$fh>;
  };
  chomp $content;
  return $content;
}

This is a really simply cheap hack:

• Query https://qa-reports.gentoo.org/output/genrdeps/ for revdeps
• Parse it
• Mangle it into {CAT}/{PN}
• Run pkgcheck scan on {CAT}/{PN}

I'm sure there's a better way to do this natively though.

[mgorny]

You're spending too much time on perl.

https://github.com/mgorny/mgorny-dev-scripts/blob/master/rdep

Much less code and supports fetching the whole revdep tree as cache.

[kentfredric]

Much less code

Of course its less code.

a. Half of that code I just forgot to remove out of something else b. It does substantially less.

[kentfredric]

fetching the whole revdep tree as cache.

Would be a simple change of

  ->get( uri )

to

  ->mirror( uri, file )

But that's not the point. This is just a trival example showing what can be done, not that it should be used wholesale this way.

[radhermit]

To do this properly, a local revdeps cache (https://github.com/pkgcore/pkgcheck/issues/285) needs to be generated as well as support for temporary cache splicing with local git repo changes. Using a remote source would often not be fully correct and therefore pointless.