Copy the contents of the %DB::sub entry if it exists

Closes RT#50524

Name.xs

@@ -67,6 +67,40 @@ subname(name, sub)
 		Safefree(namepv);
                 name = end;
         }
+
+	/* under debugger, provide information about sub location */
+	if (PL_DBsub && CvGV(cv)) {
+		HV *hv = GvHV(PL_DBsub);
+
+		char* new_pkg = HvNAME(stash);
+
+		char* old_name = GvNAME( CvGV(cv) );
+		char* old_pkg = HvNAME( GvSTASH(CvGV(cv)) );
+
+		int old_len = strlen(old_name) + strlen(old_pkg);
+		int new_len = strlen(name) + strlen(new_pkg);
+
+		char* full_name;
+		Newxz(full_name, (old_len > new_len ? old_len : new_len) + 3, char);
+
+		strcat(full_name, old_pkg);
+		strcat(full_name, "::");
+		strcat(full_name, old_name);
+
+		SV** old_data = hv_fetch(hv, full_name, strlen(full_name), 0);
+
+		if (old_data) {
+			strcpy(full_name, new_pkg);
+			strcat(full_name, "::");
+			strcat(full_name, name);
+
+			SvREFCNT_inc(*old_data);
+			if (!hv_store(hv, full_name, strlen(full_name), *old_data, 0))
+				SvREFCNT_dec(*old_data);
+		}
+		Safefree(full_name);
+	}
+
 	gv = (GV *) newSV(0);
 	gv_init(gv, stash, name, s - name, TRUE);
 

t/smoke.t

@@ -1,11 +1,15 @@
 #!/usr/bin/perl
 
-BEGIN { print "1..5\n"; }
+BEGIN { print "1..10\n"; $^P |= 0x210 }
 
 
 use Sub::Name;
 
 my $x = subname foo => sub { (caller 0)[3] };
+my $line = __LINE__ - 1;
+my $file = __FILE__;
+my $anon = $DB::sub{"main::__ANON__[${file}:${line}]"};
+
 print $x->() eq "main::foo" ? "ok 1\n" : "not ok 1\n";
 
 
@@ -26,4 +30,16 @@ for (4 .. 5) {
 	print $x->() eq "Blork::Dynamic $_" ? "ok $_\n" : "not ok $_\n";
 }
 
+print $DB::sub{"main::foo"} eq $anon ? "ok 6\n" : "not ok 6\n";
+
+for (4 .. 5) {
+	print $DB::sub{"Blork::Dynamic $_"} eq $anon ? "ok ".($_+3)."\n" : "not ok ".($_+3)."\n";
+}
+
+my $i = 9;
+for ("Blork:: Bar!", "Foo::Bar::Baz") {
+	print $DB::sub{$_} eq $anon  ? "ok $i\n" : "not ok $_ \n";
+	$i++;
+}
+
 # vim: ft=perl