Executable model isn't generated correctly for from clause in the form func(x)

    public static Integer getLength(String s) {

        return s.length();

    }

    @Test

    public void testFromExternalFunction() {

        final String str =

                "import " + FromTest.class.getCanonicalName() + ";\n" +

                "global java.util.List list\n" +

                "\n" +

                "rule R when\n" +

                "  $s : String()\n" +

                "  $i : Integer( this > 10 ) from FromTest.getLength($s)\n" +

                "then\n" +

                "  list.add( \"received long message: \" + $s);\n" +

                "end\n";

        KieSession ksession = getKieSession( str );

        final List<String> list = new ArrayList<>();

        ksession.setGlobal( "list", list );

        ksession.insert("Hello World!");

        ksession.fireAllRules();

        Assertions.assertThat(list).containsExactlyInAnyOrder("received long message: Hello World!");

    }