1 # -*- mode: cperl; tab-width: 8; indent-tabs-mode: nil; basic-offset: 2 -*-
2 # vim:ts=8:sw=2:et:sta:sts=2
3 package Module::Metadata;
5 # Adapted from Perl-licensed code originally distributed with
6 # Module-Build by Ken Williams
8 # This module provides routines to gather information about
9 # perl modules (assuming this may be expanded in the distant
10 # parrot future to look at other types of modules).
13 use vars qw($VERSION);
14 $VERSION = '1.000009';
15 $VERSION = eval $VERSION;
22 if ($INC{'Log/Contextual.pm'}) {
23 Log::Contextual->import('log_info');
25 *log_info = sub (&) { warn $_[0]->() };
28 use File::Find qw(find);
30 my $V_NUM_REGEXP = qr{v?[0-9._]+}; # crudely, a v-string or decimal
32 my $PKG_REGEXP = qr{ # match a package declaration
33 ^[\s\{;]* # intro chars on a line
34 package # the word 'package'
36 ([\w:]+) # a package name
37 \s* # optional whitespace
38 ($V_NUM_REGEXP)? # optional version number
39 \s* # optional whitesapce
40 [;\{] # semicolon line terminator or block start (since 5.16)
43 my $VARNAME_REGEXP = qr{ # match fully-qualified VERSION name
44 ([\$*]) # sigil - $ or *
46 ( # optional leading package name
47 (?:::|\')? # possibly starting like just :: (Ì la $::VERSION)
48 (?:\w+(?:::|\'))* # Foo::Bar:: ...
54 my $VERS_REGEXP = qr{ # match a VERSION definition
56 \(\s*$VARNAME_REGEXP\s*\) # with parens
58 $VARNAME_REGEXP # without parens
61 =[^=~] # = but not ==, nor =~
67 my $filename = File::Spec->rel2abs( shift );
69 return undef unless defined( $filename ) && -f $filename;
70 return $class->_init(undef, $filename, @_);
77 return undef unless defined($handle) && defined($filename);
78 $filename = File::Spec->rel2abs( $filename );
80 return $class->_init(undef, $filename, @_, handle => $handle);
90 $props{inc} ||= \@INC;
91 my $filename = $class->find_module_by_name( $module, $props{inc} );
92 return undef unless defined( $filename ) && -f $filename;
93 return $class->_init($module, $filename, %props);
98 my $compare_versions = sub {
99 my ($v1, $op, $v2) = @_;
100 $v1 = version->new($v1)
101 unless UNIVERSAL::isa($v1,'version');
103 my $eval_str = "\$v1 $op \$v2";
104 my $result = eval $eval_str;
105 log_info { "error comparing versions: '$eval_str' $@" } if $@;
110 my $normalize_version = sub {
112 if ( $version =~ /[=<>!,]/ ) { # logic, not just version
113 # take as is without modification
115 elsif ( ref $version eq 'version' ) { # version objects
116 $version = $version->is_qv ? $version->normal : $version->stringify;
118 elsif ( $version =~ /^[^v][^.]*\.[^.]+\./ ) { # no leading v, multiple dots
119 # normalize string tuples without "v": "1.2.3" -> "v1.2.3"
120 $version = "v$version";
128 # separate out some of the conflict resolution logic
130 my $resolve_module_versions = sub {
131 my $packages = shift;
133 my( $file, $version );
135 foreach my $p ( @$packages ) {
136 if ( defined( $p->{version} ) ) {
137 if ( defined( $version ) ) {
138 if ( $compare_versions->( $version, '!=', $p->{version} ) ) {
139 $err .= " $p->{file} ($p->{version})\n";
141 # same version declared multiple times, ignore
145 $version = $p->{version};
148 $file ||= $p->{file} if defined( $p->{file} );
152 $err = " $file ($version)\n" . $err;
167 croak "provides() requires key/value pairs \n" if @_ % 2;
170 croak "provides() takes only one of 'dir' or 'files'\n"
171 if $args{dir} && $args{files};
173 croak "provides() requires a 'version' argument"
174 unless defined $args{version};
176 croak "provides() does not support version '$args{version}' metadata"
177 unless grep { $args{version} eq $_ } qw/1.4 2/;
179 $args{prefix} = 'lib' unless defined $args{prefix};
183 $p = $class->package_versions_from_directory($args{dir});
186 croak "provides() requires 'files' to be an array reference\n"
187 unless ref $args{files} eq 'ARRAY';
188 $p = $class->package_versions_from_directory($args{files});
191 # Now, fix up files with prefix
192 if ( length $args{prefix} ) { # check in case disabled with q{}
193 $args{prefix} =~ s{/$}{};
194 for my $v ( values %$p ) {
195 $v->{file} = "$args{prefix}/$v->{file}";
202 sub package_versions_from_directory {
203 my ( $class, $dir, $files ) = @_;
212 push @files, $_ if -f $_ && /\.pm$/;
218 # First, we enumerate all packages & versions,
219 # separating into primary & alternative candidates
221 foreach my $file (@files) {
222 my $mapped_filename = File::Spec->abs2rel( $file, $dir );
223 my @path = split( /\//, $mapped_filename );
224 (my $prime_package = join( '::', @path )) =~ s/\.pm$//;
226 my $pm_info = $class->new_from_file( $file );
228 foreach my $package ( $pm_info->packages_inside ) {
229 next if $package eq 'main'; # main can appear numerous times, ignore
230 next if $package eq 'DB'; # special debugging package, ignore
231 next if grep /^_/, split( /::/, $package ); # private package, ignore
233 my $version = $pm_info->version( $package );
235 if ( $package eq $prime_package ) {
236 if ( exists( $prime{$package} ) ) {
237 croak "Unexpected conflict in '$package'; multiple versions found.\n";
239 $prime{$package}{file} = $mapped_filename;
240 $prime{$package}{version} = $version if defined( $version );
243 push( @{$alt{$package}}, {
244 file => $mapped_filename,
251 # Then we iterate over all the packages found above, identifying conflicts
252 # and selecting the "best" candidate for recording the file & version
254 foreach my $package ( keys( %alt ) ) {
255 my $result = $resolve_module_versions->( $alt{$package} );
257 if ( exists( $prime{$package} ) ) { # primary package selected
259 if ( $result->{err} ) {
260 # Use the selected primary package, but there are conflicting
261 # errors among multiple alternative packages that need to be
264 "Found conflicting versions for package '$package'\n" .
265 " $prime{$package}{file} ($prime{$package}{version})\n" .
269 } elsif ( defined( $result->{version} ) ) {
270 # There is a primary package selected, and exactly one
271 # alternative package
273 if ( exists( $prime{$package}{version} ) &&
274 defined( $prime{$package}{version} ) ) {
275 # Unless the version of the primary package agrees with the
276 # version of the alternative package, report a conflict
277 if ( $compare_versions->(
278 $prime{$package}{version}, '!=', $result->{version}
283 "Found conflicting versions for package '$package'\n" .
284 " $prime{$package}{file} ($prime{$package}{version})\n" .
285 " $result->{file} ($result->{version})\n"
290 # The prime package selected has no version so, we choose to
291 # use any alternative package that does have a version
292 $prime{$package}{file} = $result->{file};
293 $prime{$package}{version} = $result->{version};
297 # no alt package found with a version, but we have a prime
298 # package so we use it whether it has a version or not
301 } else { # No primary package was selected, use the best alternative
303 if ( $result->{err} ) {
305 "Found conflicting versions for package '$package'\n" .
310 # Despite possible conflicting versions, we choose to record
311 # something rather than nothing
312 $prime{$package}{file} = $result->{file};
313 $prime{$package}{version} = $result->{version}
314 if defined( $result->{version} );
318 # Normalize versions. Can't use exists() here because of bug in YAML::Node.
319 # XXX "bug in YAML::Node" comment seems irrelvant -- dagolden, 2009-05-18
320 for (grep defined $_->{version}, values %prime) {
321 $_->{version} = $normalize_version->( $_->{version} );
332 my $filename = shift;
335 my $handle = delete $props{handle};
336 my( %valid_props, @valid_props );
337 @valid_props = qw( collect_pod inc );
338 @valid_props{@valid_props} = delete( @props{@valid_props} );
339 warn "Unknown properties: @{[keys %props]}\n" if scalar( %props );
343 filename => $filename,
354 my $self = bless(\%data, $class);
357 $self->_parse_fh($handle);
360 $self->_parse_file();
363 unless($self->{module} and length($self->{module})) {
364 my ($v, $d, $f) = File::Spec->splitpath($self->{filename});
367 my @candidates = grep /$f$/, @{$self->{packages}};
368 $self->{module} = shift(@candidates); # punt
371 if(grep /main/, @{$self->{packages}}) {
372 $self->{module} = 'main';
375 $self->{module} = $self->{packages}[0] || '';
380 $self->{version} = $self->{versions}{$self->{module}}
381 if defined( $self->{module} );
387 sub _do_find_module {
389 my $module = shift || croak 'find_module_by_name() requires a package name';
390 my $dirs = shift || \@INC;
392 my $file = File::Spec->catfile(split( /::/, $module));
393 foreach my $dir ( @$dirs ) {
394 my $testfile = File::Spec->catfile($dir, $file);
395 return [ File::Spec->rel2abs( $testfile ), $dir ]
396 if -e $testfile and !-d _; # For stuff like ExtUtils::xsubpp
397 return [ File::Spec->rel2abs( "$testfile.pm" ), $dir ]
398 if -e "$testfile.pm";
404 sub find_module_by_name {
405 my $found = shift()->_do_find_module(@_) or return;
410 sub find_module_dir_by_name {
411 my $found = shift()->_do_find_module(@_) or return;
416 # given a line of perl code, attempt to parse it if it looks like a
417 # $VERSION assignment, returning sigil, full name, & package name
418 sub _parse_version_expression {
422 my( $sig, $var, $pkg );
423 if ( $line =~ $VERS_REGEXP ) {
424 ( $sig, $var, $pkg ) = $2 ? ( $1, $2, $3 ) : ( $4, $5, $6 );
426 $pkg = ($pkg eq '::') ? 'main' : $pkg;
431 return ( $sig, $var, $pkg );
437 my $filename = $self->{filename};
438 my $fh = IO::File->new( $filename )
439 or croak( "Can't open '$filename': $!" );
441 $self->_parse_fh($fh);
445 my ($self, $fh) = @_;
447 my( $in_pod, $seen_end, $need_vers ) = ( 0, 0, 0 );
448 my( @pkgs, %vers, %pod, @pod );
453 while (defined( my $line = <$fh> )) {
457 next if $line =~ /^\s*#/;
460 if ( $line =~ /^=(.{0,3})/ ) {
461 $is_cut = $1 eq 'cut';
465 # Would be nice if we could also check $in_string or something too
466 last if !$in_pod && $line =~ /^__(?:DATA|END)__$/;
468 if ( $in_pod || $is_cut ) {
470 if ( $line =~ /^=head\d\s+(.+)\s*$/ ) {
472 if ( $self->{collect_pod} && length( $pod_data ) ) {
473 $pod{$pod_sect} = $pod_data;
479 } elsif ( $self->{collect_pod} ) {
480 $pod_data .= "$line\n";
489 # parse $line to see if it's a $VERSION declaration
490 my( $vers_sig, $vers_fullname, $vers_pkg ) =
492 ? $self->_parse_version_expression( $line )
495 if ( $line =~ $PKG_REGEXP ) {
497 push( @pkgs, $pkg ) unless grep( $pkg eq $_, @pkgs );
498 $vers{$pkg} = (defined $2 ? $2 : undef) unless exists( $vers{$pkg} );
499 $need_vers = defined $2 ? 0 : 1;
501 # VERSION defined with full package spec, i.e. $Module::VERSION
502 } elsif ( $vers_fullname && $vers_pkg ) {
503 push( @pkgs, $vers_pkg ) unless grep( $vers_pkg eq $_, @pkgs );
504 $need_vers = 0 if $vers_pkg eq $pkg;
506 unless ( defined $vers{$vers_pkg} && length $vers{$vers_pkg} ) {
508 $self->_evaluate_version_line( $vers_sig, $vers_fullname, $line );
510 # Warn unless the user is using the "$VERSION = eval
511 # $VERSION" idiom (though there are probably other idioms
512 # that we should watch out for...)
513 warn <<"EOM" unless $line =~ /=\s*eval/;
514 Package '$vers_pkg' already declared with version '$vers{$vers_pkg}',
515 ignoring subsequent declaration on line $line_num.
519 # first non-comment line in undeclared package main is VERSION
520 } elsif ( !exists($vers{main}) && $pkg eq 'main' && $vers_fullname ) {
523 $self->_evaluate_version_line( $vers_sig, $vers_fullname, $line );
525 push( @pkgs, 'main' );
527 # first non-comment line in undeclared package defines package main
528 } elsif ( !exists($vers{main}) && $pkg eq 'main' && $line =~ /\w+/ ) {
531 push( @pkgs, 'main' );
533 # only keep if this is the first $VERSION seen
534 } elsif ( $vers_fullname && $need_vers ) {
537 $self->_evaluate_version_line( $vers_sig, $vers_fullname, $line );
540 unless ( defined $vers{$pkg} && length $vers{$pkg} ) {
544 Package '$pkg' already declared with version '$vers{$pkg}'
545 ignoring new version '$v' on line $line_num.
555 if ( $self->{collect_pod} && length($pod_data) ) {
556 $pod{$pod_sect} = $pod_data;
559 $self->{versions} = \%vers;
560 $self->{packages} = \@pkgs;
561 $self->{pod} = \%pod;
562 $self->{pod_headings} = \@pod;
567 sub _evaluate_version_line {
569 my( $sigil, $var, $line ) = @_;
571 # Some of this code came from the ExtUtils:: hierarchy.
573 # We compile into $vsub because 'use version' would cause
574 # compiletime/runtime issues with local()
576 $pn++; # everybody gets their own package
577 my $eval = qq{BEGIN { q# Hide from _packages_inside()
578 #; package Module::Metadata::_version::p$pn;
591 # Try to get the $VERSION
593 # some modules say $VERSION = $Foo::Bar::VERSION, but Foo::Bar isn't
594 # installed, so we need to hunt in ./lib for it
595 if ( $@ =~ /Can't locate/ && -d 'lib' ) {
596 local @INC = ('lib',@INC);
599 warn "Error evaling version line '$eval' in $self->{filename}: $@\n"
601 (ref($vsub) eq 'CODE') or
602 croak "failed to build version sub for $self->{filename}";
603 my $result = eval { $vsub->() };
604 croak "Could not get version from $self->{filename} by executing:\n$eval\n\nThe fatal error was: $@\n"
607 # Upgrade it into a version object
608 my $version = eval { _dwim_version($result) };
610 croak "Version '$result' from $self->{filename} does not appear to be valid:\n$eval\n\nThe fatal error was: $@\n"
611 unless defined $version; # "0" is OK!
617 # Try to DWIM when things fail the lax version test in obvious ways
620 # Best case, it just works
621 sub { return shift },
623 # If we still don't have a version, try stripping any
624 # trailing junk that is prohibited by lax rules
627 $v =~ s{([0-9])[a-z-].*$}{$1}i; # 1.23-alpha or 1.23b
631 # Activestate apparently creates custom versions like '1.23_45_01', which
632 # cause version.pm to think it's an invalid alpha. So check for that
636 my $num_dots = () = $v =~ m{(\.)}g;
637 my $num_unders = () = $v =~ m{(_)}g;
638 my $leading_v = substr($v,0,1) eq 'v';
639 if ( ! $leading_v && $num_dots < 2 && $num_unders > 1 ) {
641 $num_unders = () = $v =~ m{(_)}g;
646 # Worst case, try numifying it like we would have before version objects
649 no warnings 'numeric';
656 my ($result) = shift;
658 return $result if ref($result) eq 'version';
660 my ($version, $error);
661 for my $f (@version_prep) {
662 $result = $f->($result);
663 $version = eval { version->new($result) };
664 $error ||= $@ if $@; # capture first failure
665 last if defined $version;
668 croak $error unless defined $version;
674 ############################################################
677 sub name { $_[0]->{module} }
679 sub filename { $_[0]->{filename} }
680 sub packages_inside { @{$_[0]->{packages}} }
681 sub pod_inside { @{$_[0]->{pod_headings}} }
682 sub contains_pod { $#{$_[0]->{pod_headings}} }
686 my $mod = shift || $self->{module};
688 if ( defined( $mod ) && length( $mod ) &&
689 exists( $self->{versions}{$mod} ) ) {
690 return $self->{versions}{$mod};
699 if ( defined( $sect ) && length( $sect ) &&
700 exists( $self->{pod}{$sect} ) ) {
701 return $self->{pod}{$sect};
711 Module::Metadata - Gather package and POD information from perl module files
715 use Module::Metadata;
717 # information about a .pm file
718 my $info = Module::Metadata->new_from_file( $file );
719 my $version = $info->version;
721 # CPAN META 'provides' field for .pm files in a directory
722 my $provides = Module::Metadata->provides(
723 dir => 'lib', version => 2
728 This module provides a standard way to gather metadata about a .pm file
729 without executing unsafe code.
737 =item C<< new_from_file($filename, collect_pod => 1) >>
739 Construct a C<Module::Metadata> object given the path to a file. Takes an
740 optional argument C<collect_pod> which is a boolean that determines whether POD
741 data is collected and stored for reference. POD data is not collected by
742 default. POD headings are always collected. Returns undef if the filename
745 =item C<< new_from_handle($handle, $filename, collect_pod => 1) >>
747 This works just like C<new_from_file>, except that a handle can be provided
748 as the first argument. Note that there is no validation to confirm that the
749 handle is a handle or something that can act like one. Passing something that
750 isn't a handle will cause a exception when trying to read from it. The
751 C<filename> argument is mandatory or undef will be returned.
753 =item C<< new_from_module($module, collect_pod => 1, inc => \@dirs) >>
755 Construct a C<Module::Metadata> object given a module or package name. In addition
756 to accepting the C<collect_pod> argument as described above, this
757 method accepts a C<inc> argument which is a reference to an array of
758 of directories to search for the module. If none are given, the
759 default is @INC. Returns undef if the module cannot be found.
761 =item C<< find_module_by_name($module, \@dirs) >>
763 Returns the path to a module given the module or package name. A list
764 of directories can be passed in as an optional parameter, otherwise
767 Can be called as either an object or a class method.
769 =item C<< find_module_dir_by_name($module, \@dirs) >>
771 Returns the entry in C<@dirs> (or C<@INC> by default) that contains
772 the module C<$module>. A list of directories can be passed in as an
773 optional parameter, otherwise @INC is searched.
775 Can be called as either an object or a class method.
777 =item C<< provides( %options ) >>
779 This is a convenience wrapper around C<package_versions_from_directory>
780 to generate a CPAN META C<provides> data structure. It takes key/value
781 pairs. Valid option keys include:
785 =item version B<(required)>
787 Specifies which version of the L<CPAN::Meta::Spec> should be used as
788 the format of the C<provides> output. Currently only '1.4' and '2'
789 are supported (and their format is identical). This may change in
790 the future as the definition of C<provides> changes.
792 The C<version> option is required. If it is omitted or if
793 an unsupported version is given, then C<provides> will throw an error.
797 Directory to search recursively for F<.pm> files. May not be specified with
802 Array reference of files to examine. May not be specified with C<dir>.
806 String to prepend to the C<file> field of the resulting output. This defaults
807 to F<lib>, which is the common case for most CPAN distributions with their
808 F<.pm> files in F<lib>. This option ensures the META information has the
809 correct relative path even when the C<dir> or C<files> arguments are
810 absolute or have relative paths from a location other than the distribution
815 For example, given C<dir> of 'lib' and C<prefix> of 'lib', the return value
816 is a hashref of the form:
821 file => 'lib/Package/Name.pm'
823 'OtherPackage::Name' => ...
826 =item C<< package_versions_from_directory($dir, \@files?) >>
828 Scans C<$dir> for .pm files (unless C<@files> is given, in which case looks
829 for those files in C<$dir> - and reads each file for packages and versions,
830 returning a hashref of the form:
835 file => 'Package/Name.pm'
837 'OtherPackage::Name' => ...
840 The C<DB> and C<main> packages are always omitted, as are any "private"
841 packages that have leading underscores in the namespace (e.g.
844 Note that the file path is relative to C<$dir> if that is specified.
845 This B<must not> be used directly for CPAN META C<provides>. See
846 the C<provides> method instead.
848 =item C<< log_info (internal) >>
850 Used internally to perform logging; imported from Log::Contextual if
851 Log::Contextual has already been loaded, otherwise simply calls warn.
855 =head2 Object methods
861 Returns the name of the package represented by this module. If there
862 are more than one packages, it makes a best guess based on the
863 filename. If it's a script (i.e. not a *.pm) the package name is
866 =item C<< version($package) >>
868 Returns the version as defined by the $VERSION variable for the
869 package as returned by the C<name> method if no arguments are
870 given. If given the name of a package it will attempt to return the
871 version of that package if it is specified in the file.
873 =item C<< filename() >>
875 Returns the absolute path to the file.
877 =item C<< packages_inside() >>
879 Returns a list of packages. Note: this is a raw list of packages
880 discovered (or assumed, in the case of C<main>). It is not
881 filtered for C<DB>, C<main> or private packages the way the
882 C<provides> method does.
884 =item C<< pod_inside() >>
886 Returns a list of POD sections.
888 =item C<< contains_pod() >>
890 Returns true if there is any POD in the file.
892 =item C<< pod($section) >>
894 Returns the POD data in the given section.
900 Original code from Module::Build::ModuleInfo by Ken Williams
901 <kwilliams@cpan.org>, Randy W. Sims <RandyS@ThePierianSpring.org>
903 Released as Module::Metadata by Matt S Trout (mst) <mst@shadowcat.co.uk> with
904 assistance from David Golden (xdg) <dagolden@cpan.org>.
908 Original code Copyright (c) 2001-2011 Ken Williams.
909 Additional code Copyright (c) 2010-2011 Matt Trout and David Golden.
912 This library is free software; you can redistribute it and/or
913 modify it under the same terms as Perl itself.