Pass =finish POD data to Perl 5 as DATA handle

use Foo:from<Perl5>;
=finish
This data can be read by Foo by slurping <DATA>

lib/Inline/Perl5.pm6

@@ -1081,6 +1081,12 @@ method init_callbacks {
             ($p6) = @_;
         }
 
+        sub init_data {
+            my ($data) = @_;
+            no strict;
+            open *{main::DATA}, '<', \$data;
+        }
+
         sub uninit {
             undef $p6;
         }
@@ -1451,6 +1457,10 @@ class X::Inline::Perl5::NoMultiplicity is Exception {
     }
 }
 
+method init_data($data) {
+    self.call('v6::init_data', $data);
+}
+
 method BUILD(*%args) {
     my &call_method = sub (Int $index, Str $name, Int $context, Pointer $args, Pointer $err) returns Pointer {
         my $p6obj = $objects.get($index);
@@ -1510,6 +1520,13 @@ method BUILD(*%args) {
         }
     }
 
+    if ($*W) {
+        use QAST:from<NQP>;
+        my $block := { self.init_data(CALLER::<$=finish>) if CALLER::<$=finish> };
+        $*W.add_object($block);
+        my $op := $*W.add_phaser(Mu, 'INIT', $block, class :: { method cuid { (^2**128).pick }});
+    }
+
     $!external_p5 = %args<p5>:exists;
     if $!external_p5 {
         $!p5 = %args<p5>;

t/data.t

@@ -0,0 +1,13 @@
+use Test;
+#
+# DATA handle is only initialized if Inline::Perl5 is loaded at compile time of a compilation unit
+use Data::Dumper:from<Perl5>;
+
+is EVAL('<DATA>', :lang<Perl5>), "trailing data found in DATA handle\n";
+
+done-testing;
+
+=finish
+trailing data found in DATA handle
+
+# vim: ft=perl6

t/data_in_module.t

@@ -0,0 +1,7 @@
+use lib 't/lib';
+use Test;
+use Data;
+
+is look_for_data(), "trailing data found in DATA handle\n";
+
+done-testing;

t/lib/Data.pm

@@ -0,0 +1,11 @@
+use lib:from<Perl5> 't/lib';
+use LookForData:from<Perl5>;
+
+sub look_for_data() is export {
+    return LookForData::return_data;
+}
+
+=finish
+trailing data found in DATA handle
+
+# vim: ft=perl6

t/lib/LookForData.pm

@@ -0,0 +1,10 @@
+package LookForData;
+use strict;
+use warnings;
+
+sub return_data {
+    my $handle = do { no strict 'refs'; \*{"main::DATA"} };
+    return scalar <$handle>;
+}
+
+1;