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Diffstat (limited to 'cpan/CPAN-Meta/lib/CPAN/Meta/Merge.pm')
| -rw-r--r-- | cpan/CPAN-Meta/lib/CPAN/Meta/Merge.pm | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/cpan/CPAN-Meta/lib/CPAN/Meta/Merge.pm b/cpan/CPAN-Meta/lib/CPAN/Meta/Merge.pm new file mode 100644 index 0000000000..5648d77647 --- /dev/null +++ b/cpan/CPAN-Meta/lib/CPAN/Meta/Merge.pm @@ -0,0 +1,248 @@ +package CPAN::Meta::Merge; + +use strict; +use warnings; + +our $VERSION = '2.142060'; # VERSION + +use Carp qw/croak/; +use Scalar::Util qw/blessed/; +use CPAN::Meta::Converter; + +sub _identical { + my ($left, $right, $path) = @_; + croak "Can't merge attribute " . join '.', @{$path} unless $left eq $right; + return $left; +} + +sub _merge { + my ($current, $next, $mergers, $path) = @_; + for my $key (keys %{$next}) { + if (not exists $current->{$key}) { + $current->{$key} = $next->{$key}; + } + elsif (my $merger = $mergers->{$key}) { + $current->{$key} = $merger->($current->{$key}, $next->{$key}, [ @{$path}, $key ]); + } + elsif ($merger = $mergers->{':default'}) { + $current->{$key} = $merger->($current->{$key}, $next->{$key}, [ @{$path}, $key ]); + } + else { + croak sprintf "Can't merge unknown attribute '%s'", join '.', @{$path}, $key; + } + } + return $current; +} + +sub _uniq { + my %seen = (); + return grep { not $seen{$_}++ } @_; +} + +sub _set_addition { + my ($left, $right) = @_; + return [ +_uniq(@{$left}, @{$right}) ]; +} + +sub _uniq_map { + my ($left, $right, $path) = @_; + for my $key (keys %{$right}) { + if (not exists $left->{$key}) { + $left->{$key} = $right->{$key}; + } + else { + croak 'Duplication of element ' . join '.', @{$path}, $key; + } + } + return $left; +} + +sub _improvize { + my ($left, $right, $path) = @_; + my ($name) = reverse @{$path}; + if ($name =~ /^x_/) { + if (ref($left) eq 'ARRAY') { + return _set_addition($left, $right, $path); + } + elsif (ref($left) eq 'HASH') { + return _uniq_map($left, $right, $path); + } + else { + return _identical($left, $right, $path); + } + } + croak sprintf "Can't merge '%s'", join '.', @{$path}; +} + +my %default = ( + abstract => \&_identical, + author => \&_set_addition, + dynamic_config => sub { + my ($left, $right) = @_; + return $left || $right; + }, + generated_by => sub { + my ($left, $right) = @_; + return join ', ', _uniq(split(/, /, $left), split(/, /, $right)); + }, + license => \&_set_addition, + 'meta-spec' => { + version => \&_identical, + url => \&_identical + }, + name => \&_identical, + release_status => \&_identical, + version => \&_identical, + description => \&_identical, + keywords => \&_set_addition, + no_index => { map { ($_ => \&_set_addition) } qw/file directory package namespace/ }, + optional_features => \&_uniq_map, + prereqs => sub { + require CPAN::Meta::Prereqs; + my ($left, $right) = map { CPAN::Meta::Prereqs->new($_) } @_[0,1]; + return $left->with_merged_prereqs($right)->as_string_hash; + }, + provides => \&_uniq_map, + resources => { + license => \&_set_addition, + homepage => \&_identical, + bugtracker => \&_uniq_map, + repository => \&_uniq_map, + ':default' => \&_improvize, + }, + ':default' => \&_improvize, +); + +sub new { + my ($class, %arguments) = @_; + croak 'default version required' if not exists $arguments{default_version}; + my %mapping = %default; + my %extra = %{ $arguments{extra_mappings} || {} }; + for my $key (keys %extra) { + if (ref($mapping{$key}) eq 'HASH') { + $mapping{$key} = { %{ $mapping{$key} }, %{ $extra{$key} } }; + } + else { + $mapping{$key} = $extra{$key}; + } + } + return bless { + default_version => $arguments{default_version}, + mapping => _coerce_mapping(\%mapping, []), + }, $class; +} + +my %coderef_for = ( + set_addition => \&_set_addition, + uniq_map => \&_uniq_map, + identical => \&_identical, + improvize => \&_improvize, +); + +sub _coerce_mapping { + my ($orig, $map_path) = @_; + my %ret; + for my $key (keys %{$orig}) { + my $value = $orig->{$key}; + if (ref($orig->{$key}) eq 'CODE') { + $ret{$key} = $value; + } + elsif (ref($value) eq 'HASH') { + my $mapping = _coerce_mapping($value, [ @{$map_path}, $key ]); + $ret{$key} = sub { + my ($left, $right, $path) = @_; + return _merge($left, $right, $mapping, [ @{$path}, $key ]); + }; + } + elsif ($coderef_for{$value}) { + $ret{$key} = $coderef_for{$value}; + } + else { + croak "Don't know what to do with " . join '.', @{$map_path}, $key; + } + } + return \%ret; +} + +sub merge { + my ($self, @items) = @_; + my $current = {}; + for my $next (@items) { + if ( blessed($next) && $next->isa('CPAN::Meta') ) { + $next = $next->as_string_hash; + } + elsif ( ref($next) eq 'HASH' ) { + my $cmc = CPAN::Meta::Converter->new( + $next, default_version => $self->{default_version} + ); + $next = $cmc->upgrade_fragment; + } + else { + croak "Don't know how to merge '$next'"; + } + $current = _merge($current, $next, $self->{mapping}, []); + } + return $current; +} + +1; + +# ABSTRACT: Merging CPAN Meta fragments + +__END__ + +=pod + +=encoding UTF-8 + +=head1 NAME + +CPAN::Meta::Merge - Merging CPAN Meta fragments + +=head1 VERSION + +version 2.142060 + +=head1 SYNOPSIS + + my $merger = CPAN::Meta::Merge->new(default_version => "2"); + my $meta = $merger->merge($base, @additional); + +=head1 DESCRIPTION + +=head1 METHODS + +=head2 new + +This creates a CPAN::Meta::Merge object. It takes one mandatory named +argument, C<version>, declaring the version of the meta-spec that must be +used for the merge. It can optionally take an C<extra_mappings> argument +that allows one to add additional merging functions for specific elements. + +=head2 merge(@fragments) + +Merge all C<@fragments> together. It will accept both CPAN::Meta objects and +(possibly incomplete) hashrefs of metadata. + +=head1 AUTHORS + +=over 4 + +=item * + +David Golden <dagolden@cpan.org> + +=item * + +Ricardo Signes <rjbs@cpan.org> + +=back + +=head1 COPYRIGHT AND LICENSE + +This software is copyright (c) 2010 by David Golden and Ricardo Signes. + +This is free software; you can redistribute it and/or modify it under +the same terms as the Perl 5 programming language system itself. + +=cut |