Extend test.

tests/run/pure_pxd.srctree

@@ -37,6 +37,14 @@ class ExtTypeAttributes(object):
         self.b = [1, 2, 3]
 
 
+def func(a, b, c):
+    """
+    >>> func(1, 2, 3)
+    6
+    """
+    return a + b + c
+
+
 def test():
     import os.path
     assert not os.path.basename(__file__).endswith('.py'), __file__
@@ -46,6 +54,7 @@ def test():
     assert not ExtTypePass().__doc__, ExtTypePass().__doc__
     assert ExtTypeDocstring().__doc__ == "huhu!", ExtTypeDocstring().__doc__
     assert ExtTypePxdDocstring().__doc__ == "ho, ho, ho!", ExtTypePxdDocstring().__doc__
+    assert '>>> ' in func.__doc__
 
     import doctest
     doctest.testmod(verbose=True)
@@ -64,3 +73,6 @@ cdef class ExtTypePxdDocstring:
 cdef class ExtTypeAttributes:
     cdef int a
     cdef readonly list b
+
+
+cpdef int func(x, int y, z) except? -1  # argument names should not matter, types should