Fix comparison for MPComplexField

src/sage/rings/complex_mpc.pyx

@@ -61,8 +61,8 @@ import re
 import real_mpfr
 import weakref
 
-from sage.structure.parent import Parent
-from sage.structure.parent_gens import ParentWithGens
+from sage.structure.parent cimport Parent
+from sage.structure.parent_gens cimport ParentWithGens
 from sage.structure.element cimport RingElement, Element, ModuleElement
 from sage.categories.map cimport Map
 
@@ -459,7 +459,7 @@ cdef class MPComplexField_class(sage.rings.ring.Field):
         if isinstance(S, MPComplexField_class) and S.prec() >= self.__prec:
             #FIXME: What map when rounding modes differ but prec is the same ?
             #       How to provide commutativity of morphisms ?
-            #       Change __cmp__ when done
+            #       Change _cmp_ when done
             return MPCtoMPC(S, self)
 
         if isinstance(S, ComplexField_class) and S.prec() >= self.__prec:
@@ -483,9 +483,12 @@ cdef class MPComplexField_class(sage.rings.ring.Field):
         """
         return __create__MPComplexField_version0, (self.__prec, self.__rnd_str)
 
-    def __cmp__(self, other):
+    def __richcmp__(left, right, int op):
+        return (<Parent>left)._richcmp(right, op)
+
+    cpdef int _cmp_(self, right) except -2:
         """
-        Compare ``self`` and ``other``.
+        Compare ``self`` and ``other``, ignoring the rounding mode.
 
         EXAMPLES::
 
@@ -496,16 +499,12 @@ cdef class MPComplexField_class(sage.rings.ring.Field):
             sage: MPComplexField(10,rnd='RNDZN') == MPComplexField(10,rnd='RNDZU')
             True
         """
-        if not isinstance(other, MPComplexField_class):
-            return -1
-        cdef MPComplexField_class _other
-        _other = other  # to access C structure
-        #FIXME: if we choose a priority between rounding modes in
-        #order to provide commutativity of morphisms then rounding
-        #mode will matter
-        if self.__prec == _other.__prec: # and self.__rnd == _other.__rnd:
-            return 0
-        return 1
+        cdef int c = cmp(type(self), type(right))
+        if c:
+            return c
+
+        cdef MPComplexField_class other = <MPComplexField_class>right
+        return cmp(self.__prec, other.__prec)
 
     def gen(self, n=0):
         """
@@ -1169,7 +1168,14 @@ cdef class MPComplexNumber(sage.structure.element.FieldElement):
         rnd = (<MPComplexField_class>self._parent).__rnd
         return complex(mpfr_get_d(self.value.re, rnd_re(rnd)), mpfr_get_d(self.value.im, rnd_im(rnd)))
 
-    def __cmp__(self, other):
+    # Boilerplate comparison code
+    def __richcmp__(left, right, int op):
+        return (<Element>left)._richcmp(right, op)
+
+    def __cmp__(left, right):
+        return (<Element>left)._cmp(right)
+
+    cpdef int _cmp_(self, Element other) except -2:
         r"""
         Compare ``self`` to ``other``.