move version extraction guts to its own file. NO FUNCTIONALITY CHANGES YET

Author: karenetheridge

lib/Module/Metadata.pm

@@ -10,7 +10,6 @@ package Module::Metadata;
 # perl modules (assuming this may be expanded in the distant
 # parrot future to look at other types of modules).
 
-sub __clean_eval { eval $_[0] }
 use strict;
 use warnings;
 
@@ -25,6 +24,9 @@ BEGIN {
        } or *SEEK_SET = sub { 0 }
 }
 use version 0.87;
+use Module::Metadata::ExtractVersion 'eval_version';
+
+
 BEGIN {
   if ($INC{'Log/Contextual.pm'}) {
     require "Log/Contextual/WarnLogger.pm"; # Hide from AutoPrereqs
@@ -600,13 +602,23 @@ sub _parse_fh {
       $need_vers = 0 if $version_package eq $package;
 
       unless ( defined $vers_raw{$version_package}[0] && length $vers_raw{$version_package}[0] ) {
-        $vers_raw{$version_package} = [ $self->_evaluate_version_line( $version_sigil, $version_fullname, $line ), $line ];
+        $vers_raw{$version_package} = [ eval_version(
+          sigil => $version_sigil,
+          variable_name => $version_fullname,
+          string => $line,
+          filename => $self->{filename},
+        ), $line ];
       }
 
     # first non-comment line in undeclared package main is VERSION
     } elsif ( $package eq 'main' && $version_fullname && !exists($vers_raw{main}[0]) ) {
       $need_vers = 0;
-      my $v = $self->_evaluate_version_line( $version_sigil, $version_fullname, $line );
+      my $v = eval_version(
+        sigil => $version_sigil,
+        variable_name => $version_fullname,
+        string => $line,
+        filename => $self->{filename},
+      );
       $vers_raw{$package} = [ $v, $line ];
       push( @packages, 'main' );
 
@@ -619,9 +631,14 @@ sub _parse_fh {
     # only keep if this is the first $VERSION seen
     } elsif ( $version_fullname && $need_vers ) {
       $need_vers = 0;
-      my $v = $self->_evaluate_version_line( $version_sigil, $version_fullname, $line );
-
-      unless ( exists $vers_raw{$package}[0]  && length $vers{$package}[0] ) {
+      my $v = eval_version(
+        sigil => $version_sigil,
+        variable_name => $version_fullname,
+        string => $line,
+        filename => $self->{filename},
+      );
+
+      unless ( exists $vers_raw{$package}[0]  && length $vers_raw{$package}[0] ) {
         $vers_raw{$package} = [ $v, $line ];
       }
     }
@@ -652,51 +669,6 @@ sub _parse_fh {
   $self->{pod_headings} = \@pod;
 }
 
-{
-my $pn = 0;
-sub _evaluate_version_line {
-  my $self = shift;
-  my( $sigil, $variable_name, $line ) = @_;
-
-  # We compile into a local sub because 'use version' would cause
-  # compiletime/runtime issues with local()
-  $pn++; # everybody gets their own package
-  my $eval = qq{ my \$dummy = q#  Hide from _packages_inside()
-    #; package Module::Metadata::_version::p${pn};
-    use version;
-    sub {
-      local $sigil$variable_name;
-      $line;
-      \$$variable_name
-    };
-  };
-
-  $eval = $1 if $eval =~ m{^(.+)}s;
-
-  local $^W;
-  # Try to get the $VERSION
-  my $vsub = __clean_eval($eval);
-  # some modules say $VERSION <equal sign> $Foo::Bar::VERSION, but Foo::Bar isn't
-  # installed, so we need to hunt in ./lib for it
-  if ( $@ =~ /Can't locate/ && -d 'lib' ) {
-    local @INC = ('lib',@INC);
-    $vsub = __clean_eval($eval);
-  }
-  warn "Error evaling version line '$eval' in $self->{filename}: $@\n"
-    if $@;
-
-  (ref($vsub) eq 'CODE') or
-    croak "failed to build version sub for $self->{filename}";
-
-  my $result = eval { $vsub->() };
-  # FIXME: $eval is not the right thing to print here
-  croak "Could not get version from $self->{filename} by executing:\n$eval\n\nThe fatal error was: $@\n"
-    if $@;
-
-  return $result;
-}
-}
-
 # Try to DWIM when things fail the lax version test in obvious ways
 {
   my @version_prep = (

lib/Module/Metadata/ExtractVersion.pm

@@ -0,0 +1,84 @@
+package Module::Metadata::ExtractVersion;
+# ABSTRACT: Safe parsing of module $VERSION lines
+
+sub __clean_eval { eval $_[0] }
+
+use strict;
+use warnings;
+
+our $VERSION = '1.000028';
+
+use base 'Exporter';
+our @EXPORT_OK = qw/eval_version/;
+
+use Carp qw/croak/;
+use version 0.87;
+
+=func eval_version
+
+Given a (decoded) string (usually a single line) that contains a C<$VERSION>
+declaration, this function will evaluate it in a L<Safe> compartment in a
+separate process.  If the C<$VERSION> is a valid version string according to
+L<version>, it will return it as a string, otherwise, it will return undef.
+
+=cut
+
+sub eval_version
+{
+    my (%args) = @_;
+
+    return _evaluate_version_line(
+        $args{sigil},
+        $args{variable_name},
+        $args{string},
+        $args{filename},
+    );
+}
+
+# transported directly from Module::Metadata
+
+{
+my $pn = 0;
+sub _evaluate_version_line {
+  my( $sigil, $variable_name, $line, $filename ) = @_;
+
+  # We compile into a local sub because 'use version' would cause
+  # compiletime/runtime issues with local()
+  $pn++; # everybody gets their own package
+  my $eval = qq{ my \$dummy = q#  Hide from _packages_inside()
+    #; package Module::Metadata::_version::p${pn};
+    use version;
+    sub {
+      local $sigil$variable_name;
+      $line;
+      \$$variable_name
+    };
+  };
+
+  $eval = $1 if $eval =~ m{^(.+)}s;
+
+  local $^W;
+  # Try to get the $VERSION
+  my $vsub = __clean_eval($eval);
+  # some modules say $VERSION <equal sign> $Foo::Bar::VERSION, but Foo::Bar isn't
+  # installed, so we need to hunt in ./lib for it
+  if ( $@ =~ /Can't locate/ && -d 'lib' ) {
+    local @INC = ('lib',@INC);
+    $vsub = __clean_eval($eval);
+  }
+  warn "Error evaling version line '$eval' in $filename: $@\n"
+    if $@;
+
+  (ref($vsub) eq 'CODE') or
+    croak "failed to build version sub for $filename";
+
+  my $result = eval { $vsub->() };
+  # FIXME: $eval is not the right thing to print here
+  croak "Could not get version from $filename by executing:\n$eval\n\nThe fatal error was: $@\n"
+    if $@;
+
+  return $result;
+}
+}
+
+1;