Trac 18246: use WithEqualityById

src/sage/combinat/root_system/hecke_algebra_representation.py

@@ -11,14 +11,15 @@
 import functools
 from sage.misc.abstract_method import abstract_method
 from sage.misc.cachefunc import cached_method
+from sage.misc.fast_method import WithEqualityById
 from sage.structure.sage_object import SageObject
 from sage.structure.unique_representation import UniqueRepresentation
 from sage.sets.family import Family
 from sage.combinat.subset import Subsets
 from sage.rings.infinity import infinity
 from sage.rings.integer_ring import ZZ
 
-class HeckeAlgebraRepresentation(SageObject):
+class HeckeAlgebraRepresentation(WithEqualityById, SageObject):
     r"""
     A representation of an (affine) Hecke algebra given by the action of the `T` generators
 
@@ -64,6 +65,16 @@ class HeckeAlgebraRepresentation(SageObject):
         sage: H.Y()
         Lazy family (...)_{i in Coroot lattice of the Root system of type ['A', 3, 1]}
 
+    TESTS::
+
+        sage: from sage.combinat.root_system.hecke_algebra_representation import HeckeAlgebraRepresentation
+        sage: W = SymmetricGroup(3)
+        sage: domain = W.algebra(QQ)
+        sage: action = lambda x,i: domain.monomial(x.apply_simple_reflection(i, side="right"))
+        sage: r = HeckeAlgebraRepresentation(domain, action, CartanType(["A",2]), 1, -1)
+        sage: hash(r) # random
+        3
+
     REFERENCES:
 
     .. [HST2008] F. Hivert, A. Schilling, N. Thiery,
@@ -89,20 +100,6 @@ def __init__(self, domain, on_basis, cartan_type, q1, q2, q=1, side="right"):
         self._cartan_type = cartan_type
         self._side = side
 
-    def __hash__(self):
-        r"""
-        TESTS::
-
-            sage: from sage.combinat.root_system.hecke_algebra_representation import HeckeAlgebraRepresentation
-            sage: W = SymmetricGroup(3)
-            sage: domain = W.algebra(QQ)
-            sage: action = lambda x,i: domain.monomial(x.apply_simple_reflection(i, side="right"))
-            sage: r = HeckeAlgebraRepresentation(domain, action, CartanType(["A",2]), 1, -1)
-            sage: hash(r) # random
-            3
-        """
-        return id(self)
-
     def _repr_(self):
         r"""
         EXAMPLES::

src/sage/geometry/triangulation/base.pyx

@@ -17,8 +17,7 @@ AUTHORS:
 #                  http://www.gnu.org/licenses/
 ########################################################################
 
-
-
+from sage.misc.fast_methods cimport hash_by_id
 from sage.structure.sage_object cimport SageObject
 from sage.structure.parent cimport Parent
 from sage.categories.sets_cat import Sets
@@ -107,7 +106,7 @@ cdef class Point(SageObject):
             sage: hash(p[0]) # random
             35822008390213632
         """
-        return id(self._point_configuration) ^ self._index
+        return hash(self._point_configuration) ^ (<long>self._index)
 
     cpdef point_configuration(self):
         r"""
@@ -466,7 +465,6 @@ cdef class PointConfiguration_base(Parent):
         self._pts = tuple([ Point(self, i, proj.column(i), aff.column(i), red.column(i))
                            for i in range(0,n) ])
 
-
     def __hash__(self):
         r"""
         Hash function.
@@ -477,7 +475,7 @@ cdef class PointConfiguration_base(Parent):
             sage: hash(p) # random
             8746748042501
         """
-        return id(self)
+        return hash_by_id(<void *> self)
 
     cpdef reduced_affine_vector_space(self):
         """

src/sage/misc/fast_methods.pxd

@@ -1,2 +1,19 @@
+cdef extern from "Python.h":
+    cdef size_t SIZEOF_VOID_P
+
 cdef class FastHashable_class:
     cdef Py_ssize_t _hash
+
+cdef inline long hash_by_id(void * p):
+    r"""
+    This function is a copy paste from the default Python hash function.
+    """
+    cdef long x
+    cdef size_t y = <size_t>p
+    # bottom 3 or 4 bits are likely to be 0; rotate y by 4 to avoid
+    # excessive hash collisions for dicts and sets
+    y = (y >> 4) | (y << (8 * SIZEOF_VOID_P - 4))
+    x = <long>y
+    if x == -1:
+        x = -2
+    return x

src/sage/misc/fast_methods.pyx

@@ -40,7 +40,8 @@ from sage.misc.lazy_attribute import lazy_class_attribute
 from cpython.bool cimport *
 from cpython.ref cimport *
 
-cdef int SIZEOF_VOID_P_SHIFT = 8*sizeof(void *) - 4
+cdef extern from "Python.h":
+    cdef size_t SIZEOF_VOID_P
 
 cdef class WithEqualityById:
     """
@@ -150,15 +151,14 @@ cdef class WithEqualityById:
             sage: hash(a) == object.__hash__(a)
             True
 
+            sage: from sage.misc.fast_methods import WithEqualityById
+            sage: o1 = WithEqualityById()
+            sage: o2 = WithEqualityById()
+            sage: hash(o1) == hash(o2)
+            False
         """
         # This is the default hash function in Python's object.c:
-        cdef long x
-        cdef size_t y = <size_t><void *>self
-        y = (y >> 4) | (y << SIZEOF_VOID_P_SHIFT)
-        x = <long>y
-        if x==-1:
-            x = -2
-        return x
+        return hash_by_id(<void *>self)
 
     def __richcmp__(self, other, int m):
         """

src/sage/numerical/linear_functions.pyx

@@ -78,9 +78,7 @@ See :trac:`12091` ::
 include "sage/ext/interrupt.pxi"
 from cpython.object cimport *
 
-cdef extern from "limits.h":
-    long LONG_MAX
-
+from sage.misc.fast_methods cimport hash_by_id
 from sage.structure.parent cimport Parent
 from sage.structure.element cimport ModuleElement, Element
 from sage.misc.cachefunc import cached_function
@@ -941,7 +939,7 @@ cdef class LinearFunction(ModuleElement):
             sage: d[f] = 3
         """
         # see _cmp_() if you want to change the hash function
-        return id(self) % LONG_MAX
+        return hash_by_id(<void *> self)
 
     def __cmp__(left, right):
         """

src/sage/numerical/linear_tensor_element.pyx

@@ -21,9 +21,7 @@ Here is an example of a linear function tensored with a vector space::
 
 from cpython.object cimport *
 
-cdef extern from "limits.h":
-    long LONG_MAX
-
+from sage.misc.fast_methods cimport hash_by_id
 from sage.structure.element cimport ModuleElement, RingElement
 from sage.numerical.linear_functions cimport LinearFunction, is_LinearFunction
 
@@ -460,7 +458,7 @@ cdef class LinearTensor(ModuleElement):
             sage: d[f] = 3
         """
         # see _cmp_() if you want to change the hash function
-        return id(self) % LONG_MAX
+        return hash_by_id(<void *> self)
 
     def __cmp__(left, right):
         """

src/sage/plot/animate.py

@@ -117,6 +117,7 @@
 import struct
 import zlib
 
+from sage.misc.fast_methods import WithEqualityById
 from sage.structure.sage_object import SageObject
 from sage.misc.temporary_file import tmp_dir, tmp_filename, graphics_filename
 import plot
@@ -139,7 +140,7 @@ def animate(frames, **kwds):
     """
     return Animation(frames, **kwds)
 
-class Animation(SageObject):
+class Animation(WithEqualityById, SageObject):
     r"""
     Return an animation of a sequence of plots of objects.
 
@@ -215,6 +216,11 @@ class Animation(SageObject):
         sage: a._frames
         <generator object ...
 
+    TESTS::
+
+        sage: from sage.plot.animate import Animation
+        sage: hash(Animation()) # random
+        140658972348064
     """
     def __init__(self, v=None, **kwds):
         r"""
@@ -266,16 +272,6 @@ def _combine_kwds(self, *kwds_tuple):
                 new_kwds[name] = getattr(__builtin__, name[1:])(values)
         return new_kwds
 
-    def __hash__(self):
-        r"""
-        TESTS::
-
-            sage: from sage.plot.animate import Animation
-            sage: hash(Animation()) # random
-            140658972348064
-        """
-        return id(self)
-
     def __getitem__(self, i):
         """
         Get a frame from an animation or

src/sage/plot/graphics.py

@@ -33,6 +33,7 @@
 import sage.misc.misc
 from sage.misc.html import html
 from sage.misc.temporary_file import tmp_filename
+from sage.misc.fast_methods import WithEqualityById
 from sage.structure.sage_object import SageObject
 from sage.misc.decorators import suboptions
 from colors import rgbcolor
@@ -84,7 +85,7 @@ def is_Graphics(x):
     """
     return isinstance(x, Graphics)
 
-class Graphics(SageObject):
+class Graphics(WithEqualityById, SageObject):
     """
     The Graphics object is an empty list of graphics objects. It is
     useful to use this object when initializing a for loop where
@@ -134,6 +135,11 @@ class Graphics(SageObject):
         sage: isinstance(g2, Graphics)
         True
 
+    TESTS::
+
+        sage: hash(Graphics()) # random
+        42
+
     .. automethod:: _rich_repr_
     """
 
@@ -159,17 +165,6 @@ def __init__(self):
         self._show_legend = False
         self._tick_label_color = (0, 0, 0)
 
-    def __hash__(self):
-        r"""
-        Graphics objects are all different!
-
-        TESTS::
-
-            sage: hash(Graphics()) # random
-            42
-        """
-        return id(self)
-
     def set_aspect_ratio(self, ratio):
         """
         Set the aspect ratio, which is the ratio of height and width
@@ -3237,7 +3232,7 @@ def description(self):
         return '\n'.join(g[1] for g in data)
 
 
-class GraphicsArray(SageObject):
+class GraphicsArray(WithEqualityById, SageObject):
     """
     GraphicsArray takes a (`m` x `n`) list of lists of
     graphics objects and plots them all on one canvas.
@@ -3279,6 +3274,9 @@ def __init__(self, array):
             Traceback (most recent call last):
             ...
             TypeError: every element of array must be a Graphics object
+
+            sage: hash(graphics_array([])) # random
+            42
         """
         if not isinstance(array, (list, tuple)):
             raise TypeError("array (=%s) must be a list of lists of Graphics objects"%(array))
@@ -3302,15 +3300,6 @@ def __init__(self, array):
                 self._glist.append(g)
         self._figsize = None
 
-    def __hash__(self):
-        r"""
-        TESTS::
-
-            sage: hash(graphics_array([])) # random
-            42
-        """
-        return id(self)
-
     def _repr_(self):
         """
         Representation of the graphics array.

src/sage/plot/plot3d/base.pyx

@@ -29,8 +29,8 @@ AUTHORS:
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
-
 from cpython.list cimport *
+from cpython.object cimport PyObject
 
 import os
 from functools import reduce
@@ -42,6 +42,8 @@ from sage.misc.misc import sage_makedirs
 from sage.env import SAGE_LOCAL
 from sage.doctest import DOCTEST_MODE
 
+from sage.misc.fast_methods cimport hash_by_id
+
 from sage.modules.free_module_element import vector
 
 from sage.rings.real_double import RDF
@@ -87,7 +89,7 @@ cdef class Graphics3d(SageObject):
             sage: hash(Graphics3d()) # random
             140658972348064
         """
-        return id(self)
+        return hash_by_id(<void *> self)
 
     def _repr_(self):
         """

src/sage/plot/plot3d/tachyon.py

@@ -139,6 +139,7 @@
 
 from sage.interfaces.tachyon import tachyon_rt
 
+from sage.misc.fast_methods import WithEqualityById
 from sage.structure.sage_object import SageObject
 
 from sage.misc.misc import SAGE_TMP
@@ -153,7 +154,7 @@
 from math import sqrt
 
 
-class Tachyon(SageObject):
+class Tachyon(WithEqualityById, SageObject):
     r"""
     Create a scene the can be rendered using the Tachyon ray tracer.
 
@@ -334,6 +335,11 @@ class Tachyon(SageObject):
         ....:         tt = 't1'
         ....:     T.sphere((q, q/3+.3*sin(3*q), .1+.3*cos(3*q)), .1, tt)
         sage: T.show()
+
+    TESTS::
+
+        sage: hash(Tachyon()) # random
+        140658972348064
     """
     def __init__(self,
                  xres=350, yres=350,
@@ -380,15 +386,6 @@ def __init__(self,
         else:
             self._viewdir = viewdir
 
-    def __hash__(self):
-        r"""
-        TESTS::
-
-            sage: hash(Tachyon()) # random
-            140658972348064
-        """
-        return id(self)
-
     def save_image(self, filename=None, *args, **kwds):
         r"""
         Save an image representation of ``self``.