gh-40156: Support Cython 3.1
    
In Cython 3.1 binary operations are no longer wrappers, but methods.
This breaks wrapperdescr_fastcall.

Since this was rather hackish anyway, we replace its few uses by
explicit coercions.

We also switch some modules to compile with `binding=True`, this fixes
many errors with 3.1.
    
URL: #40156
Reported by: Antonio Rojas
Reviewer(s): Dima Pasechnik

Author: Release Manager

pkgs/sagemath-categories/known-test-failures.json

@@ -803,10 +803,6 @@
     "sage.cpython.type": {
         "ntests": 7
     },
-    "sage.cpython.wrapperdescr": {
-        "failed": true,
-        "ntests": 0
-    },
     "sage.doctest.check_tolerance": {
         "failed": true,
         "ntests": 19

src/doc/en/reference/cpython/index.rst

@@ -12,7 +12,6 @@ internals.
    sage/cpython/debug
    sage/cpython/getattr
    sage/cpython/cython_metaclass
-   sage/cpython/wrapperdescr
    sage/cpython/dict_del_by_value
 
 .. include:: ../footer.txt

src/sage/algebras/lie_algebras/lie_algebra_element.pyx

@@ -22,7 +22,6 @@ from cpython.object cimport Py_EQ, Py_NE, Py_GT, Py_GE
 from sage.misc.repr import repr_lincomb
 from sage.structure.element cimport have_same_parent, parent
 from sage.structure.coerce cimport coercion_model
-from sage.cpython.wrapperdescr cimport wrapperdescr_fastcall
 from sage.structure.element_wrapper cimport ElementWrapper
 from sage.structure.richcmp cimport richcmp, richcmp_not_equal
 from sage.data_structures.blas_dict cimport axpy, add, negate, scal
@@ -66,11 +65,28 @@ cdef class LieAlgebraElement(IndexedFreeModuleElement):
         """
         try:
             # Try the normal coercion first
-            return wrapperdescr_fastcall(IndexedFreeModuleElement.__mul__,
-                                         left, (right,), <object>NULL)
+            return IndexedFreeModuleElement.__mul__(left, right)
         except TypeError:
             pass
 
+        try:
+            # Handle the case of right multiplication by scalar
+            if isinstance(left, IndexedFreeModuleElement):
+                R = (<IndexedFreeModuleElement>left)._parent._base
+                x = R.coerce(right)
+                return IndexedFreeModuleElement.__mul__(left, x)
+        except (TypeError, KeyError):
+            pass
+
+        try:
+            # Handle the case of left multiplication by scalar
+            if isinstance(right, IndexedFreeModuleElement):
+                R = (<IndexedFreeModuleElement>right)._parent._base
+                x = R.coerce(left)
+                return IndexedFreeModuleElement.__mul__(x, right)
+        except (TypeError, KeyError):
+            pass
+
         # Lift up to the UEA and try multiplication there
         # We will eventually want to lift stuff up anyways,
         #   so just do it here.
@@ -349,11 +365,28 @@ cdef class LieAlgebraElementWrapper(ElementWrapper):
         """
         try:
             # Try the normal coercion first
-            return wrapperdescr_fastcall(ElementWrapper.__mul__,
-                                         left, (right,), <object>NULL)
+            return ElementWrapper.__mul__(left, right)
         except TypeError:
             pass
 
+        try:
+            # Handle the case of right multiplication by scalar
+            if isinstance(left, LieAlgebraElementWrapper):
+                R = (<LieAlgebraElementWrapper>left)._parent._base
+                x = R.coerce(right)
+                return ElementWrapper.__mul__(left, x)
+        except (TypeError, KeyError):
+            pass
+
+        try:
+            # Handle the case of left multiplication by scalar
+            if isinstance(right, LieAlgebraElementWrapper):
+                R = (<LieAlgebraElementWrapper>right)._parent._base
+                x = R.coerce(left)
+                return ElementWrapper.__mul__(x, right)
+        except (TypeError, KeyError):
+            pass
+
         # Lift up to the UEA and try multiplication there
         # We will eventually want to lift stuff up anyways,
         #   so just do it here.

src/sage/combinat/sloane_functions.py

@@ -8911,7 +8911,7 @@ def __getattribute__(self, name):
         ::
 
             sage: sloane.__repr__
-            <built-in method __repr__ of Sloane object at 0x...>
+            <...__repr__...of Sloane object at 0x...>
             sage: sloane.__name__
             Traceback (most recent call last):
             ...

src/sage/cpython/meson.build

@@ -28,7 +28,6 @@ extension_data = {
   'getattr' : files('getattr.pyx'),
   'string' : files('string.pyx'),
   'type' : files('type.pyx'),
-  'wrapperdescr' : files('wrapperdescr.pyx'),
 }
 
 foreach name, pyx : extension_data

src/sage/cpython/wrapperdescr.pyx

@@ -35,6 +35,7 @@ Classes and methods
 -------------------
 """
 
+cimport cython
 from cysignals.memory cimport check_calloc, sig_free
 
 from sage.graphs.base.static_sparse_graph cimport (init_short_digraph,
@@ -1545,6 +1546,7 @@ cdef class StaticSparseBackend(CGraphBackend):
         (<StaticSparseCGraph> self._cg).del_vertex(v)
 
 
+@cython.binding(True)
 def _run_it_on_static_instead(f):
     r"""
     A decorator function to force the (Di)Graph functions to compute from a

src/sage/graphs/base/static_sparse_backend.pyx

@@ -957,7 +957,7 @@ def is_complete_multipartite(int v, int k, int l, int mu):
 
         sage: from sage.graphs.strongly_regular_db import is_complete_multipartite
         sage: t = is_complete_multipartite(12,8,4,8); t
-        (<cyfunction is_complete_multipartite.<locals>.CompleteMultipartiteSRG at ...>,
+        (<...CompleteMultipartiteSRG...>,
          3,
          4)
         sage: g = t[0](*t[1:]); g
@@ -1492,7 +1492,7 @@ def is_twograph_descendant_of_srg(int v, int k0, int l, int mu):
 
         sage: from sage.graphs.strongly_regular_db import is_twograph_descendant_of_srg
         sage: t = is_twograph_descendant_of_srg(27, 10, 1, 5); t                        # needs sage.rings.finite_rings
-        (<cyfunction is_twograph_descendant_of_srg.<locals>.la at...
+        (<...is_twograph_descendant_of_srg...>, (8,))
         sage: g = t[0](*t[1:]); g                                                       # needs sage.rings.finite_rings
         descendant of complement(Johnson graph with parameters 8,2) at {0, 1}: Graph on 27 vertices
         sage: g.is_strongly_regular(parameters=True)                                    # needs sage.rings.finite_rings
@@ -1662,9 +1662,9 @@ def is_switch_OA_srg(int v, int k, int l, int mu):
         sage: t[0](*t[1:]).is_strongly_regular(parameters=True)                         # needs sage.schemes
         (290, 136, 63, 64)
         sage: is_switch_OA_srg(626, 300, 143, 144)                                      # needs sage.schemes
-        (<cyfunction is_switch_OA_srg.<locals>.switch_OA_srg at ..., 12, 25)
+        (<...switch_OA_srg..., 12, 25)
         sage: is_switch_OA_srg(842, 406, 195, 196)                                      # needs sage.schemes
-        (<cyfunction is_switch_OA_srg.<locals>.switch_OA_srg at ..., 14, 29)
+        (<...switch_OA_srg..., 14, 29)
     """
     cdef int n_2_p_1 = v
     cdef int n = <int> floor(sqrt(n_2_p_1 - 1))
@@ -2920,21 +2920,21 @@ def strongly_regular_graph_lazy(int v, int k, int l, int mu=-1, bint existence=F
 
         sage: from sage.graphs.strongly_regular_db import strongly_regular_graph_lazy
         sage: g,p=strongly_regular_graph_lazy(10,6,3); g,p
-        (<cyfunction is_johnson.<locals>.<lambda> at ...>, 5)
+        (<...is_johnson...>, 5)
         sage: g(p)
         Johnson graph with parameters 5,2: Graph on 10 vertices
         sage: g,p=strongly_regular_graph_lazy(10,3,0,1); g,p
-        (<cyfunction strongly_regular_graph_lazy.<locals>.<lambda> at...>,
+        (<...strongly_regular_graph_lazy...>,
          (5,))
         sage: g(p)
         complement(Johnson graph with parameters 5,2): Graph on 10 vertices
         sage: g,p=strongly_regular_graph_lazy(12,3,2); g,p
-        (<cyfunction strongly_regular_graph_lazy.<locals>.<lambda> at...>,
+        (<...strongly_regular_graph_lazy...>,
          (3, 4))
         sage: g(p)
         complement(Multipartite Graph with set sizes [4, 4, 4]): Graph on 12 vertices
         sage: g = strongly_regular_graph_lazy(539,250,105); g                           # needs sage.combinat sage.modules
-        (<cyfunction is_twograph_descendant_of_srg.<locals>.la at...>,
+        (<...is_twograph_descendant_of_srg...>,
          5,
          11)
         sage: g[0](*g[1:])                                                              # needs sage.combinat sage.modules

src/sage/graphs/strongly_regular_db.pyx

@@ -1121,7 +1121,7 @@ class HierarchyElement(object, metaclass=ClasscallMetaclass):
         to reconstruct an element of the hierarchy from its value::
 
             sage: x._from_value                                                         # needs sage.graphs
-            Cached version of <cyfunction HierarchyElement.__classcall__.<locals>.f at ...>
+            Cached version of <...__classcall__...>
             sage: x._from_value(x.value) is x                                           # needs sage.graphs
             True
         """

src/sage/misc/c3_controlled.pyx

@@ -202,7 +202,9 @@ def isclassinstance(obj):
             # Starting with Cython 3, Cython's builtin types have __module__ set
             # to the shared module names like _cython_3_0_0.
             not (isinstance(obj.__class__.__module__, str) and
-                 obj.__class__.__module__.startswith('_cython_')))
+                 obj.__class__.__module__.startswith('_cython_')) and
+            # In Cython 3.1, they have 'member_descriptor' type
+            'cython_function_or_method' not in str(obj.__class__.__module__))
 
 
 # Parse strings of form "File: sage/rings/rational.pyx (starting at line 1080)"