cython

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# mode: run
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PYTHON setup.py build_ext --inplace
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PYTHON -c "import classes"
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PYTHON -c "import test_inherit"
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######## setup.py ########
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from Cython.Build.Dependencies import cythonize
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from distutils.core import setup
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setup(
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  ext_modules=cythonize("*.pyx"),
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)
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######  dummy_module.py ###########
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tpl = tuple
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lst = list
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###### classes.pxd ################
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cdef extern from *:
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    # apart from list, these are all variable sized types
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    # and Cython shouldn't trip up about the struct size
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    ctypedef class dummy_module.tpl [object PyTupleObject]:
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        pass
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    ctypedef class dummy_module.lst [object PyListObject]:
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        pass
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    ctypedef class types.CodeType [object PyCodeObject]:
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        pass
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    # Note that bytes doesn't work here because it further 
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    # the tp_basicsize to save space
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##### classes.pyx #################
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def check_tuple(tpl x):
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    assert isinstance(x, tuple)
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def check_list(lst x):
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    assert isinstance(x, list)
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def check_code(CodeType x):
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    import types
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    assert isinstance(x, types.CodeType)
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check_tuple((1, 2))
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check_list([1, 2])
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check_code(eval("lambda: None").__code__)
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##### failed_inherit1.pyx #############
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from classes cimport tpl
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cdef class SuperTuple(tpl):
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    cdef int a  # importing this gives an error message
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##### failed_inherit2.pyx #############
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from classes cimport tpl
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cdef class SuperTuple(tpl):
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    # adding a method creates a vtab so should also fail
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    cdef int func(self):
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        return 1
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##### successful_inherit.pyx #########
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from classes cimport lst, tpl
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cdef class SuperList(lst):
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    cdef int a  # This works OK
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cdef class SuperTuple(tpl):
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    # This is actually OK because it doesn't add anything
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    pass
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##### test_inherit.py ################
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try:
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    import failed_inherit1
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except TypeError as e:
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    assert e.args[0] == "inheritance from PyVarObject types like 'tuple' not currently supported", e.args[0]
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else:
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    assert False
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try:
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    import failed_inherit2
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except TypeError as e:
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    assert e.args[0] == "inheritance from PyVarObject types like 'tuple' not currently supported", e.args[0]
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else:
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    assert False
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import successful_inherit
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