[cups-devel] [ipptool] How do I request stapled output?

[pipitas]

I used ipptool to query an IPP-2.0 capable print device for its attributes,
using a self-written *.test file.

Within the printer's reply I found the following:

~~~
finishings-supported (1setOf enum) =
none,staple,punch,edge-stitch,staple-top-left,\

staple-top-right,edge-stitch-left,edge-stitch-top,edge-stitch-right,staple-dual-left,\

staple-dual-top,staple-dual-right,cups-punch-dual-left,cups-punch-dual-top,\

cups-punch-dual-right,cups-punch-quad-left,cups-punch-quad-top,cups-punch-quad-right
~~~

(I'm wondering how a printer vendor would name some punching options with a
"cups-" prefix. Or have such name types become part of official IPP specs?
Also, I'm wondering about the possible differences in "edge-stitch-left",
"staple-dual-left"? What is the difference between "staple" and "stitch"?
However, this is not my main concern currently...)

I wrote another *.test file with Print-Job containing the following lines:

~~~
        GROUP job-attributes-tag
        ATTR keyword media "iso_a4_210x297mm"
        ATTR integer copies 1
        ATTR keyword sides two-sided-short-edge
        ATTR enum finishings staple
        FILE document-a4.pdf
~~~

This leads to an error:

~~~
ipptool: Bad enum value "staple-top-left" on line 26.
~~~

If I comment out the respective line in my *.test file, the document prints
succesfully (but un-stapled).

If I replace the respective line with the following...

~~~
        ATTR enum finishings staple
~~~

...the job also prints, but again un-stapled.

My questions are:

1. Did I construct my original *.test file correctly for requesting the
stapling?
2. Or is this a bug in ipptool?
3. What is the generic method to specify arbitrary job attributes in a
*.test file (for which the printer had reported to support them)?