How does one retrieve \rpcode values in LuaTeX?

Question

The \rpcode values from pdfTeX are properties of font characters, e.g.,

\rpcode\font 50 = 200

sets the right protrusion value for character 50 in the current font to 200. Reading chapter 7 of the luatex reference manual my understanding is that this value then shows up in the character table for this particular character as right_protrusion. However, this is either not the case or I do something wrong, here is a minimal example:

\pdfprotrudechars=2

\rpcode\font 50 = 200
\efcode\font 50 = 333

\directlua{

local function FMItable (name,t)
    print ("---- looking at table ", name, tostring(t))
      for k, v in pairs(t) do
    print("    ", k,"=", tostring(v))
      end
    print("----------------")
end

 FMItable("char 50",font.fonts[font.current()].characters[50])

}
\bye

If run through luatex this generates

luatex rp-test.tex
This is LuaTeX, Version beta-0.79.1 (TeX Live 2014/W32TeX) (rev 4971) 
 restricted \write18 enabled.
(./rp-test.tex---- looking at table     char 50 table: 02FB5E10
    height  =   422343
    used    =   false
    width   =   327681
    bot_accent  =   0
    italic  =   0
    expansion_factor    =   333
    depth   =   0
    top_accent  =   0
----------------
)
No pages of output.
Transcript written on rp-test.log.

You can see the changed \efcode so I'm getting at the right character table but no index for protrusion. Any idea what I'm doing wrong?

Answer 1

This seems to be fixed in the current 0.80 release

This is LuaTeX, Version beta-0.80.0 (TeX Live 2015) (rev 5238) 
 restricted \write18 enabled.
(./gg384.tex---- looking at table       char 50 table: 0x60106f270
        depth   =       0
        used    =       false
        width   =       327681
        expansion_factor        =       333
        right_protruding        =       200
        height  =       422343
----------------
)
No pages of output.

showing

        right_protruding        =       200

is reported.