Test failures in R interface

[Antonio Rojas]

Hi,

 I've been seeing these failures for a while when running the doctests. It is not reproducible when testing the file standalone, only when testing the full sage library, which makes it really hard to debug. Has anybody seen this or has any idea how to fix it?

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File "/usr/lib/python3.10/site-packages/sage/interfaces/r.py", line 697, in sage.interfaces.r.R.__reduce__
Failed example:
   rlr, t = r.__reduce__()  # optional - rpy2
Exception raised:
   Traceback (most recent call last):
     File "/usr/lib/python3.10/site-packages/sage/doctest/forker.py", line 695, in _run
       self.compile_and_execute(example, compiler, test.globs)
     File "/usr/lib/python3.10/site-packages/sage/doctest/forker.py", line 1093, in compile_and_execute
       exec(compiled, globs)
     File "<doctest sage.interfaces.r.R.__reduce__[0]>", line 1, in <module>
       rlr, t = r.__reduce__()  # optional - rpy2
     File "/usr/lib/python3.10/copyreg.py", line 76, in _reduce_ex
       raise TypeError(f"cannot pickle {cls.__name__!r} object")
   TypeError: cannot pickle 'LazyImport' object
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File "/usr/lib/python3.10/site-packages/sage/interfaces/r.py", line 698, in sage.interfaces.r.R.__reduce__
Failed example:
   rlr(*t)  # optional - rpy2
Exception raised:
   Traceback (most recent call last):
     File "/usr/lib/python3.10/site-packages/sage/doctest/forker.py", line 695, in _run
       self.compile_and_execute(example, compiler, test.globs)
     File "/usr/lib/python3.10/site-packages/sage/doctest/forker.py", line 1093, in compile_and_execute
       exec(compiled, globs)
     File "<doctest sage.interfaces.r.R.__reduce__[1]>", line 1, in <module>
       rlr(*t)  # optional - rpy2
   NameError: name 'rlr' is not defined
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File "/usr/lib/python3.10/site-packages/sage/interfaces/r.py", line 1265, in sage.interfaces.r.R.plot
Failed example:
   with TemporaryDirectory() as d: # optional - rpy2, rgraphics
       _ = r.setwd(d)
       r.plot("1:10")
Exception raised:
   Traceback (most recent call last):
     File "/usr/lib/python3.10/site-packages/sage/doctest/forker.py", line 695, in _run
       self.compile_and_execute(example, compiler, test.globs)
     File "/usr/lib/python3.10/site-packages/sage/doctest/forker.py", line 1093, in compile_and_execute
       exec(compiled, globs)
     File "<doctest sage.interfaces.r.R.plot[1]>", line 2, in <module>
       _ = r.setwd(d)
     File "/usr/lib/python3.10/site-packages/sage/interfaces/r.py", line 1988, in __call__
       return self._parent.function_call(self._name, args=list(args), kwds=kwds)
     File "/usr/lib/python3.10/site-packages/sage/interfaces/r.py", line 1061, in function_call
       args, kwds = self._convert_args_kwds(args, kwds)
     File "/usr/lib/python3.10/site-packages/sage/interfaces/interface.py", line 572, in _convert_args_kwds
       args[i] = self(arg)
     File "/usr/lib/python3.10/site-packages/sage/interfaces/interface.py", line 298, in __call__
       return cls(self, x, name=name)
     File "/usr/lib/python3.10/site-packages/sage/interfaces/interface.py", line 749, in __init__
       self._name = parent._create(value, name=name)
     File "/usr/lib/python3.10/site-packages/sage/interfaces/interface.py", line 516, in _create
       self.set(name, value)
     File "/usr/lib/python3.10/site-packages/sage/interfaces/r.py", line 1110, in set
       out = self.eval(cmd)
     File "/usr/lib/python3.10/site-packages/sage/interfaces/r.py", line 1325, in eval
       return str(robjects.r(code)).rstrip()
     File "/usr/lib/python3.10/site-packages/rpy2/robjects/__init__.py", line 458, in __call__
       p = rinterface.parse(string)
     File "/usr/lib/python3.10/site-packages/rpy2/rinterface_lib/conversion.py", line 45, in _
       cdata = function(*args, **kwargs)
     File "/usr/lib/python3.10/site-packages/rpy2/rinterface.py", line 110, in parse
       res = _rinterface._parse(robj.__sexp__._cdata, num, rmemory)
     File "/usr/lib/python3.10/site-packages/rpy2/rinterface_lib/_rinterface_capi.py", line 720, in _parse
       raise RParsingError('Parsing status not OK',
   rpy2.rinterface_lib._rinterface_capi.RParsingError: Parsing status not OK - PARSING_STATUS.PARSE_ERROR
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