Error compiling specification with multiple WITH COMPONENTS constraints chained with OR operator

[Dave-Krch]

I have encountered error while trying to compile TS 102 894-2 v2.2.1 https://github.com/riebl/vanetza/blob/master/asn1/release2/TS102894-2v221-CDD.asn

[proc] [.\comptest\TS102894-2v221-CDD.asn] module ETSI-ITS-CDD (oid: [0, 4, 0, 5, 1, 102894, 2, 4, 1]): 341 ASN.1 assignments found
--- compilation cycle ---
Traceback (most recent call last):
  File "D:\bp\pycrate\tools\pycrate_asn1compile.py", line 264, in <module>
    sys.exit(main())
             ^^^^^^
  File "D:\bp\pycrate\tools\pycrate_asn1compile.py", line 215, in main
    compile_text(txt, **ckw)
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnproc.py", line 254, in compile_text
    compile_modules(remain)
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnproc.py", line 942, in compile_modules
    ObjNew = asnobj_compile(Obj)
             ^^^^^^^^^^^^^^^^^^^
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnproc.py", line 876, in asnobj_compile
    text = Obj.parse_def(Obj._text_def)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnobj.py", line 1716, in parse_def
    rest = self._parse_const(text)
           ^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnobj.py", line 3964, in _parse_const
    self._parse_const_val(const)
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnobj.py", line 4033, in _parse_const_val
    self.parse_set(const['text'])
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnobj.py", line 5844, in parse_set
    rest = self._parse_set_comp(rv, val, dom)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnobj.py", line 6080, in _parse_set_comp
    return self.parse_value(text)
           ^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnobj.py", line 4611, in parse_value
    return getattr(self, self._PARSE_VALUE_DISPATCH[self._type])(text)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnobj.py", line 5486, in _parse_value_seqof
    return self._parse_value_ref(text)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\dejfd\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages\pycrate_asn1c\asnobj.py", line 4626, in _parse_value_ref
    raise(ASN1ProcTextErr('{0}: invalid value reference for {1}, {2}'\
pycrate_asn1c.err.ASN1ProcTextErr: EventZone: invalid value reference for SEQUENCE OF, (WITH COMPONENT (WITH COMPONENTS {..., eventDeltaTime PRESENT}))

I also reproduced the error with this minimal ASN.1 specification:

Test DEFINITIONS AUTOMATIC TAGS ::=

BEGIN

Test ::= SEQUENCE {
    a INTEGER OPTIONAL,
    b INTEGER OPTIONAL
} ((WITH COMPONENTS {..., a PRESENT}) | (WITH COMPONENTS {..., b PRESENT}))

END

Is this known limitation of pycrate?

[mitshell]

Yes, the support of WITH COMPONENTS is buggy in the compiler. Additionally, I'm not sure it's also well implemented in the runtime side... Thank you for providing a minimal example exhibiting the issue. Regarding the stack trace, it seems the compiler tries to parse a value constraint, and does not even enter the _parse_const_withcomps() method (https://github.com/pycrate-org/pycrate/blob/fe6a308dcee661de4276b49c68666f76998776d2/pycrate_asn1c/asnobj.py#L4258C9-L4258C32). This is clearly a problem here on the parsing of general constraints for SEQUENCE, SET and CHOICE (and maybe more).