I am done

rl/Lib/site-packages/sympy/multipledispatch/__init__.py

@@ -0,0 +1,11 @@
+from .core import dispatch
+from .dispatcher import (Dispatcher, halt_ordering, restart_ordering,
+    MDNotImplementedError)
+
+__version__ = '0.4.9'
+
+__all__ = [
+    'dispatch',
+
+    'Dispatcher', 'halt_ordering', 'restart_ordering', 'MDNotImplementedError',
+]

rl/Lib/site-packages/sympy/multipledispatch/conflict.py

@@ -0,0 +1,68 @@
+from .utils import _toposort, groupby
+
+class AmbiguityWarning(Warning):
+    pass
+
+
+def supercedes(a, b):
+    """ A is consistent and strictly more specific than B """
+    return len(a) == len(b) and all(map(issubclass, a, b))
+
+
+def consistent(a, b):
+    """ It is possible for an argument list to satisfy both A and B """
+    return (len(a) == len(b) and
+            all(issubclass(aa, bb) or issubclass(bb, aa)
+                           for aa, bb in zip(a, b)))
+
+
+def ambiguous(a, b):
+    """ A is consistent with B but neither is strictly more specific """
+    return consistent(a, b) and not (supercedes(a, b) or supercedes(b, a))
+
+
+def ambiguities(signatures):
+    """ All signature pairs such that A is ambiguous with B """
+    signatures = list(map(tuple, signatures))
+    return {(a, b) for a in signatures for b in signatures
+                       if hash(a) < hash(b)
+                       and ambiguous(a, b)
+                       and not any(supercedes(c, a) and supercedes(c, b)
+                                    for c in signatures)}
+
+
+def super_signature(signatures):
+    """ A signature that would break ambiguities """
+    n = len(signatures[0])
+    assert all(len(s) == n for s in signatures)
+
+    return [max([type.mro(sig[i]) for sig in signatures], key=len)[0]
+               for i in range(n)]
+
+
+def edge(a, b, tie_breaker=hash):
+    """ A should be checked before B
+
+    Tie broken by tie_breaker, defaults to ``hash``
+    """
+    if supercedes(a, b):
+        if supercedes(b, a):
+            return tie_breaker(a) > tie_breaker(b)
+        else:
+            return True
+    return False
+
+
+def ordering(signatures):
+    """ A sane ordering of signatures to check, first to last
+
+    Topoological sort of edges as given by ``edge`` and ``supercedes``
+    """
+    signatures = list(map(tuple, signatures))
+    edges = [(a, b) for a in signatures for b in signatures if edge(a, b)]
+    edges = groupby(lambda x: x[0], edges)
+    for s in signatures:
+        if s not in edges:
+            edges[s] = []
+    edges = {k: [b for a, b in v] for k, v in edges.items()}
+    return _toposort(edges)

rl/Lib/site-packages/sympy/multipledispatch/core.py

@@ -0,0 +1,83 @@
+from __future__ import annotations
+from typing import Any
+
+import inspect
+
+from .dispatcher import Dispatcher, MethodDispatcher, ambiguity_warn
+
+# XXX: This parameter to dispatch isn't documented and isn't used anywhere in
+# sympy. Maybe it should just be removed.
+global_namespace: dict[str, Any] = {}
+
+
+def dispatch(*types, namespace=global_namespace, on_ambiguity=ambiguity_warn):
+    """ Dispatch function on the types of the inputs
+
+    Supports dispatch on all non-keyword arguments.
+
+    Collects implementations based on the function name.  Ignores namespaces.
+
+    If ambiguous type signatures occur a warning is raised when the function is
+    defined suggesting the additional method to break the ambiguity.
+
+    Examples
+    --------
+
+    >>> from sympy.multipledispatch import dispatch
+    >>> @dispatch(int)
+    ... def f(x):
+    ...     return x + 1
+
+    >>> @dispatch(float)
+    ... def f(x): # noqa: F811
+    ...     return x - 1
+
+    >>> f(3)
+    4
+    >>> f(3.0)
+    2.0
+
+    Specify an isolated namespace with the namespace keyword argument
+
+    >>> my_namespace = dict()
+    >>> @dispatch(int, namespace=my_namespace)
+    ... def foo(x):
+    ...     return x + 1
+
+    Dispatch on instance methods within classes
+
+    >>> class MyClass(object):
+    ...     @dispatch(list)
+    ...     def __init__(self, data):
+    ...         self.data = data
+    ...     @dispatch(int)
+    ...     def __init__(self, datum): # noqa: F811
+    ...         self.data = [datum]
+    """
+    types = tuple(types)
+
+    def _(func):
+        name = func.__name__
+
+        if ismethod(func):
+            dispatcher = inspect.currentframe().f_back.f_locals.get(
+                name,
+                MethodDispatcher(name))
+        else:
+            if name not in namespace:
+                namespace[name] = Dispatcher(name)
+            dispatcher = namespace[name]
+
+        dispatcher.add(types, func, on_ambiguity=on_ambiguity)
+        return dispatcher
+    return _
+
+
+def ismethod(func):
+    """ Is func a method?
+
+    Note that this has to work as the method is defined but before the class is
+    defined.  At this stage methods look like functions.
+    """
+    signature = inspect.signature(func)
+    return signature.parameters.get('self', None) is not None

rl/Lib/site-packages/sympy/multipledispatch/dispatcher.py

@@ -0,0 +1,413 @@
+from __future__ import annotations
+
+from warnings import warn
+import inspect
+from .conflict import ordering, ambiguities, super_signature, AmbiguityWarning
+from .utils import expand_tuples
+import itertools as itl
+
+
+class MDNotImplementedError(NotImplementedError):
+    """ A NotImplementedError for multiple dispatch """
+
+
+### Functions for on_ambiguity
+
+def ambiguity_warn(dispatcher, ambiguities):
+    """ Raise warning when ambiguity is detected
+
+    Parameters
+    ----------
+    dispatcher : Dispatcher
+        The dispatcher on which the ambiguity was detected
+    ambiguities : set
+        Set of type signature pairs that are ambiguous within this dispatcher
+
+    See Also:
+        Dispatcher.add
+        warning_text
+    """
+    warn(warning_text(dispatcher.name, ambiguities), AmbiguityWarning)
+
+
+class RaiseNotImplementedError:
+    """Raise ``NotImplementedError`` when called."""
+
+    def __init__(self, dispatcher):
+        self.dispatcher = dispatcher
+
+    def __call__(self, *args, **kwargs):
+        types = tuple(type(a) for a in args)
+        raise NotImplementedError(
+            "Ambiguous signature for %s: <%s>" % (
+            self.dispatcher.name, str_signature(types)
+        ))
+
+def ambiguity_register_error_ignore_dup(dispatcher, ambiguities):
+    """
+    If super signature for ambiguous types is duplicate types, ignore it.
+    Else, register instance of ``RaiseNotImplementedError`` for ambiguous types.
+
+    Parameters
+    ----------
+    dispatcher : Dispatcher
+        The dispatcher on which the ambiguity was detected
+    ambiguities : set
+        Set of type signature pairs that are ambiguous within this dispatcher
+
+    See Also:
+        Dispatcher.add
+        ambiguity_warn
+    """
+    for amb in ambiguities:
+        signature = tuple(super_signature(amb))
+        if len(set(signature)) == 1:
+            continue
+        dispatcher.add(
+            signature, RaiseNotImplementedError(dispatcher),
+            on_ambiguity=ambiguity_register_error_ignore_dup
+        )
+
+###
+
+
+_unresolved_dispatchers: set[Dispatcher] = set()
+_resolve = [True]
+
+
+def halt_ordering():
+    _resolve[0] = False
+
+
+def restart_ordering(on_ambiguity=ambiguity_warn):
+    _resolve[0] = True
+    while _unresolved_dispatchers:
+        dispatcher = _unresolved_dispatchers.pop()
+        dispatcher.reorder(on_ambiguity=on_ambiguity)
+
+
+class Dispatcher:
+    """ Dispatch methods based on type signature
+
+    Use ``dispatch`` to add implementations
+
+    Examples
+    --------
+
+    >>> from sympy.multipledispatch import dispatch
+    >>> @dispatch(int)
+    ... def f(x):
+    ...     return x + 1
+
+    >>> @dispatch(float)
+    ... def f(x): # noqa: F811
+    ...     return x - 1
+
+    >>> f(3)
+    4
+    >>> f(3.0)
+    2.0
+    """
+    __slots__ = '__name__', 'name', 'funcs', 'ordering', '_cache', 'doc'
+
+    def __init__(self, name, doc=None):
+        self.name = self.__name__ = name
+        self.funcs = {}
+        self._cache = {}
+        self.ordering = []
+        self.doc = doc
+
+    def register(self, *types, **kwargs):
+        """ Register dispatcher with new implementation
+
+        >>> from sympy.multipledispatch.dispatcher import Dispatcher
+        >>> f = Dispatcher('f')
+        >>> @f.register(int)
+        ... def inc(x):
+        ...     return x + 1
+
+        >>> @f.register(float)
+        ... def dec(x):
+        ...     return x - 1
+
+        >>> @f.register(list)
+        ... @f.register(tuple)
+        ... def reverse(x):
+        ...     return x[::-1]
+
+        >>> f(1)
+        2
+
+        >>> f(1.0)
+        0.0
+
+        >>> f([1, 2, 3])
+        [3, 2, 1]
+        """
+        def _(func):
+            self.add(types, func, **kwargs)
+            return func
+        return _
+
+    @classmethod
+    def get_func_params(cls, func):
+        if hasattr(inspect, "signature"):
+            sig = inspect.signature(func)
+            return sig.parameters.values()
+
+    @classmethod
+    def get_func_annotations(cls, func):
+        """ Get annotations of function positional parameters
+        """
+        params = cls.get_func_params(func)
+        if params:
+            Parameter = inspect.Parameter
+
+            params = (param for param in params
+                      if param.kind in
+                      (Parameter.POSITIONAL_ONLY,
+                       Parameter.POSITIONAL_OR_KEYWORD))
+
+            annotations = tuple(
+                param.annotation
+                for param in params)
+
+            if not any(ann is Parameter.empty for ann in annotations):
+                return annotations
+
+    def add(self, signature, func, on_ambiguity=ambiguity_warn):
+        """ Add new types/method pair to dispatcher
+
+        >>> from sympy.multipledispatch import Dispatcher
+        >>> D = Dispatcher('add')
+        >>> D.add((int, int), lambda x, y: x + y)
+        >>> D.add((float, float), lambda x, y: x + y)
+
+        >>> D(1, 2)
+        3
+        >>> D(1, 2.0)
+        Traceback (most recent call last):
+        ...
+        NotImplementedError: Could not find signature for add: <int, float>
+
+        When ``add`` detects a warning it calls the ``on_ambiguity`` callback
+        with a dispatcher/itself, and a set of ambiguous type signature pairs
+        as inputs.  See ``ambiguity_warn`` for an example.
+        """
+        # Handle annotations
+        if not signature:
+            annotations = self.get_func_annotations(func)
+            if annotations:
+                signature = annotations
+
+        # Handle union types
+        if any(isinstance(typ, tuple) for typ in signature):
+            for typs in expand_tuples(signature):
+                self.add(typs, func, on_ambiguity)
+            return
+
+        for typ in signature:
+            if not isinstance(typ, type):
+                str_sig = ', '.join(c.__name__ if isinstance(c, type)
+                                    else str(c) for c in signature)
+                raise TypeError("Tried to dispatch on non-type: %s\n"
+                                "In signature: <%s>\n"
+                                "In function: %s" %
+                                (typ, str_sig, self.name))
+
+        self.funcs[signature] = func
+        self.reorder(on_ambiguity=on_ambiguity)
+        self._cache.clear()
+
+    def reorder(self, on_ambiguity=ambiguity_warn):
+        if _resolve[0]:
+            self.ordering = ordering(self.funcs)
+            amb = ambiguities(self.funcs)
+            if amb:
+                on_ambiguity(self, amb)
+        else:
+            _unresolved_dispatchers.add(self)
+
+    def __call__(self, *args, **kwargs):
+        types = tuple([type(arg) for arg in args])
+        try:
+            func = self._cache[types]
+        except KeyError:
+            func = self.dispatch(*types)
+            if not func:
+                raise NotImplementedError(
+                    'Could not find signature for %s: <%s>' %
+                    (self.name, str_signature(types)))
+            self._cache[types] = func
+        try:
+            return func(*args, **kwargs)
+
+        except MDNotImplementedError:
+            funcs = self.dispatch_iter(*types)
+            next(funcs)  # burn first
+            for func in funcs:
+                try:
+                    return func(*args, **kwargs)
+                except MDNotImplementedError:
+                    pass
+            raise NotImplementedError("Matching functions for "
+                                      "%s: <%s> found, but none completed successfully"
+                                      % (self.name, str_signature(types)))
+
+    def __str__(self):
+        return "<dispatched %s>" % self.name
+    __repr__ = __str__
+
+    def dispatch(self, *types):
+        """ Deterimine appropriate implementation for this type signature
+
+        This method is internal.  Users should call this object as a function.
+        Implementation resolution occurs within the ``__call__`` method.
+
+        >>> from sympy.multipledispatch import dispatch
+        >>> @dispatch(int)
+        ... def inc(x):
+        ...     return x + 1
+
+        >>> implementation = inc.dispatch(int)
+        >>> implementation(3)
+        4
+
+        >>> print(inc.dispatch(float))
+        None
+
+        See Also:
+            ``sympy.multipledispatch.conflict`` - module to determine resolution order
+        """
+
+        if types in self.funcs:
+            return self.funcs[types]
+
+        try:
+            return next(self.dispatch_iter(*types))
+        except StopIteration:
+            return None
+
+    def dispatch_iter(self, *types):
+        n = len(types)
+        for signature in self.ordering:
+            if len(signature) == n and all(map(issubclass, types, signature)):
+                result = self.funcs[signature]
+                yield result
+
+    def resolve(self, types):
+        """ Deterimine appropriate implementation for this type signature
+
+        .. deprecated:: 0.4.4
+            Use ``dispatch(*types)`` instead
+        """
+        warn("resolve() is deprecated, use dispatch(*types)",
+             DeprecationWarning)
+
+        return self.dispatch(*types)
+
+    def __getstate__(self):
+        return {'name': self.name,
+                'funcs': self.funcs}
+
+    def __setstate__(self, d):
+        self.name = d['name']
+        self.funcs = d['funcs']
+        self.ordering = ordering(self.funcs)
+        self._cache = {}
+
+    @property
+    def __doc__(self):
+        docs = ["Multiply dispatched method: %s" % self.name]
+
+        if self.doc:
+            docs.append(self.doc)
+
+        other = []
+        for sig in self.ordering[::-1]:
+            func = self.funcs[sig]
+            if func.__doc__:
+                s = 'Inputs: <%s>\n' % str_signature(sig)
+                s += '-' * len(s) + '\n'
+                s += func.__doc__.strip()
+                docs.append(s)
+            else:
+                other.append(str_signature(sig))
+
+        if other:
+            docs.append('Other signatures:\n    ' + '\n    '.join(other))
+
+        return '\n\n'.join(docs)
+
+    def _help(self, *args):
+        return self.dispatch(*map(type, args)).__doc__
+
+    def help(self, *args, **kwargs):
+        """ Print docstring for the function corresponding to inputs """
+        print(self._help(*args))
+
+    def _source(self, *args):
+        func = self.dispatch(*map(type, args))
+        if not func:
+            raise TypeError("No function found")
+        return source(func)
+
+    def source(self, *args, **kwargs):
+        """ Print source code for the function corresponding to inputs """
+        print(self._source(*args))
+
+
+def source(func):
+    s = 'File: %s\n\n' % inspect.getsourcefile(func)
+    s = s + inspect.getsource(func)
+    return s
+
+
+class MethodDispatcher(Dispatcher):
+    """ Dispatch methods based on type signature
+
+    See Also:
+        Dispatcher
+    """
+
+    @classmethod
+    def get_func_params(cls, func):
+        if hasattr(inspect, "signature"):
+            sig = inspect.signature(func)
+            return itl.islice(sig.parameters.values(), 1, None)
+
+    def __get__(self, instance, owner):
+        self.obj = instance
+        self.cls = owner
+        return self
+
+    def __call__(self, *args, **kwargs):
+        types = tuple([type(arg) for arg in args])
+        func = self.dispatch(*types)
+        if not func:
+            raise NotImplementedError('Could not find signature for %s: <%s>' %
+                                      (self.name, str_signature(types)))
+        return func(self.obj, *args, **kwargs)
+
+
+def str_signature(sig):
+    """ String representation of type signature
+
+    >>> from sympy.multipledispatch.dispatcher import str_signature
+    >>> str_signature((int, float))
+    'int, float'
+    """
+    return ', '.join(cls.__name__ for cls in sig)
+
+
+def warning_text(name, amb):
+    """ The text for ambiguity warnings """
+    text = "\nAmbiguities exist in dispatched function %s\n\n" % (name)
+    text += "The following signatures may result in ambiguous behavior:\n"
+    for pair in amb:
+        text += "\t" + \
+            ', '.join('[' + str_signature(s) + ']' for s in pair) + "\n"
+    text += "\n\nConsider making the following additions:\n\n"
+    text += '\n\n'.join(['@dispatch(' + str_signature(super_signature(s))
+                         + ')\ndef %s(...)' % name for s in amb])
+    return text

rl/Lib/site-packages/sympy/multipledispatch/tests/test_conflict.py

@@ -0,0 +1,62 @@
+from sympy.multipledispatch.conflict import (supercedes, ordering, ambiguities,
+        ambiguous, super_signature, consistent)
+
+
+class A: pass
+class B(A): pass
+class C: pass
+
+
+def test_supercedes():
+    assert supercedes([B], [A])
+    assert supercedes([B, A], [A, A])
+    assert not supercedes([B, A], [A, B])
+    assert not supercedes([A], [B])
+
+
+def test_consistent():
+    assert consistent([A], [A])
+    assert consistent([B], [B])
+    assert not consistent([A], [C])
+    assert consistent([A, B], [A, B])
+    assert consistent([B, A], [A, B])
+    assert not consistent([B, A], [B])
+    assert not consistent([B, A], [B, C])
+
+
+def test_super_signature():
+    assert super_signature([[A]]) == [A]
+    assert super_signature([[A], [B]]) == [B]
+    assert super_signature([[A, B], [B, A]]) == [B, B]
+    assert super_signature([[A, A, B], [A, B, A], [B, A, A]]) == [B, B, B]
+
+
+def test_ambiguous():
+    assert not ambiguous([A], [A])
+    assert not ambiguous([A], [B])
+    assert not ambiguous([B], [B])
+    assert not ambiguous([A, B], [B, B])
+    assert ambiguous([A, B], [B, A])
+
+
+def test_ambiguities():
+    signatures = [[A], [B], [A, B], [B, A], [A, C]]
+    expected = {((A, B), (B, A))}
+    result = ambiguities(signatures)
+    assert set(map(frozenset, expected)) == set(map(frozenset, result))
+
+    signatures = [[A], [B], [A, B], [B, A], [A, C], [B, B]]
+    expected = set()
+    result = ambiguities(signatures)
+    assert set(map(frozenset, expected)) == set(map(frozenset, result))
+
+
+def test_ordering():
+    signatures = [[A, A], [A, B], [B, A], [B, B], [A, C]]
+    ord = ordering(signatures)
+    assert ord[0] == (B, B) or ord[0] == (A, C)
+    assert ord[-1] == (A, A) or ord[-1] == (A, C)
+
+
+def test_type_mro():
+    assert super_signature([[object], [type]]) == [type]

rl/Lib/site-packages/sympy/multipledispatch/tests/test_core.py

@@ -0,0 +1,213 @@
+from __future__ import annotations
+from typing import Any
+
+from sympy.multipledispatch import dispatch
+from sympy.multipledispatch.conflict import AmbiguityWarning
+from sympy.testing.pytest import raises, warns
+from functools import partial
+
+test_namespace: dict[str, Any] = {}
+
+orig_dispatch = dispatch
+dispatch = partial(dispatch, namespace=test_namespace)
+
+
+def test_singledispatch():
+    @dispatch(int)
+    def f(x): # noqa:F811
+        return x + 1
+
+    @dispatch(int)
+    def g(x): # noqa:F811
+        return x + 2
+
+    @dispatch(float) # noqa:F811
+    def f(x): # noqa:F811
+        return x - 1
+
+    assert f(1) == 2
+    assert g(1) == 3
+    assert f(1.0) == 0
+
+    assert raises(NotImplementedError, lambda: f('hello'))
+
+
+def test_multipledispatch():
+    @dispatch(int, int)
+    def f(x, y): # noqa:F811
+        return x + y
+
+    @dispatch(float, float) # noqa:F811
+    def f(x, y): # noqa:F811
+        return x - y
+
+    assert f(1, 2) == 3
+    assert f(1.0, 2.0) == -1.0
+
+
+class A: pass
+class B: pass
+class C(A): pass
+class D(C): pass
+class E(C): pass
+
+
+def test_inheritance():
+    @dispatch(A)
+    def f(x): # noqa:F811
+        return 'a'
+
+    @dispatch(B) # noqa:F811
+    def f(x): # noqa:F811
+        return 'b'
+
+    assert f(A()) == 'a'
+    assert f(B()) == 'b'
+    assert f(C()) == 'a'
+
+
+def test_inheritance_and_multiple_dispatch():
+    @dispatch(A, A)
+    def f(x, y): # noqa:F811
+        return type(x), type(y)
+
+    @dispatch(A, B) # noqa:F811
+    def f(x, y): # noqa:F811
+        return 0
+
+    assert f(A(), A()) == (A, A)
+    assert f(A(), C()) == (A, C)
+    assert f(A(), B()) == 0
+    assert f(C(), B()) == 0
+    assert raises(NotImplementedError, lambda: f(B(), B()))
+
+
+def test_competing_solutions():
+    @dispatch(A)
+    def h(x): # noqa:F811
+        return 1
+
+    @dispatch(C) # noqa:F811
+    def h(x): # noqa:F811
+        return 2
+
+    assert h(D()) == 2
+
+
+def test_competing_multiple():
+    @dispatch(A, B)
+    def h(x, y): # noqa:F811
+        return 1
+
+    @dispatch(C, B) # noqa:F811
+    def h(x, y): # noqa:F811
+        return 2
+
+    assert h(D(), B()) == 2
+
+
+def test_competing_ambiguous():
+    test_namespace = {}
+    dispatch = partial(orig_dispatch, namespace=test_namespace)
+
+    @dispatch(A, C)
+    def f(x, y): # noqa:F811
+        return 2
+
+    with warns(AmbiguityWarning, test_stacklevel=False):
+        @dispatch(C, A) # noqa:F811
+        def f(x, y): # noqa:F811
+            return 2
+
+    assert f(A(), C()) == f(C(), A()) == 2
+    # assert raises(Warning, lambda : f(C(), C()))
+
+
+def test_caching_correct_behavior():
+    @dispatch(A)
+    def f(x): # noqa:F811
+        return 1
+
+    assert f(C()) == 1
+
+    @dispatch(C)
+    def f(x): # noqa:F811
+        return 2
+
+    assert f(C()) == 2
+
+
+def test_union_types():
+    @dispatch((A, C))
+    def f(x): # noqa:F811
+        return 1
+
+    assert f(A()) == 1
+    assert f(C()) == 1
+
+
+def test_namespaces():
+    ns1 = {}
+    ns2 = {}
+
+    def foo(x):
+        return 1
+    foo1 = orig_dispatch(int, namespace=ns1)(foo)
+
+    def foo(x):
+        return 2
+    foo2 = orig_dispatch(int, namespace=ns2)(foo)
+
+    assert foo1(0) == 1
+    assert foo2(0) == 2
+
+
+"""
+Fails
+def test_dispatch_on_dispatch():
+    @dispatch(A)
+    @dispatch(C)
+    def q(x): # noqa:F811
+        return 1
+
+    assert q(A()) == 1
+    assert q(C()) == 1
+"""
+
+
+def test_methods():
+    class Foo:
+        @dispatch(float)
+        def f(self, x): # noqa:F811
+            return x - 1
+
+        @dispatch(int) # noqa:F811
+        def f(self, x): # noqa:F811
+            return x + 1
+
+        @dispatch(int)
+        def g(self, x): # noqa:F811
+            return x + 3
+
+
+    foo = Foo()
+    assert foo.f(1) == 2
+    assert foo.f(1.0) == 0.0
+    assert foo.g(1) == 4
+
+
+def test_methods_multiple_dispatch():
+    class Foo:
+        @dispatch(A, A)
+        def f(x, y): # noqa:F811
+            return 1
+
+        @dispatch(A, C) # noqa:F811
+        def f(x, y): # noqa:F811
+            return 2
+
+
+    foo = Foo()
+    assert foo.f(A(), A()) == 1
+    assert foo.f(A(), C()) == 2
+    assert foo.f(C(), C()) == 2

rl/Lib/site-packages/sympy/multipledispatch/tests/test_dispatcher.py

@@ -0,0 +1,284 @@
+from sympy.multipledispatch.dispatcher import (Dispatcher, MDNotImplementedError,
+                                         MethodDispatcher, halt_ordering,
+                                         restart_ordering,
+                                         ambiguity_register_error_ignore_dup)
+from sympy.testing.pytest import raises, warns
+
+
+def identity(x):
+    return x
+
+
+def inc(x):
+    return x + 1
+
+
+def dec(x):
+    return x - 1
+
+
+def test_dispatcher():
+    f = Dispatcher('f')
+    f.add((int,), inc)
+    f.add((float,), dec)
+
+    with warns(DeprecationWarning, test_stacklevel=False):
+        assert f.resolve((int,)) == inc
+    assert f.dispatch(int) is inc
+
+    assert f(1) == 2
+    assert f(1.0) == 0.0
+
+
+def test_union_types():
+    f = Dispatcher('f')
+    f.register((int, float))(inc)
+
+    assert f(1) == 2
+    assert f(1.0) == 2.0
+
+
+def test_dispatcher_as_decorator():
+    f = Dispatcher('f')
+
+    @f.register(int)
+    def inc(x): # noqa:F811
+        return x + 1
+
+    @f.register(float) # noqa:F811
+    def inc(x): # noqa:F811
+        return x - 1
+
+    assert f(1) == 2
+    assert f(1.0) == 0.0
+
+
+def test_register_instance_method():
+
+    class Test:
+        __init__ = MethodDispatcher('f')
+
+        @__init__.register(list)
+        def _init_list(self, data):
+            self.data = data
+
+        @__init__.register(object)
+        def _init_obj(self, datum):
+            self.data = [datum]
+
+    a = Test(3)
+    b = Test([3])
+    assert a.data == b.data
+
+
+def test_on_ambiguity():
+    f = Dispatcher('f')
+
+    def identity(x): return x
+
+    ambiguities = [False]
+
+    def on_ambiguity(dispatcher, amb):
+        ambiguities[0] = True
+
+    f.add((object, object), identity, on_ambiguity=on_ambiguity)
+    assert not ambiguities[0]
+    f.add((object, float), identity, on_ambiguity=on_ambiguity)
+    assert not ambiguities[0]
+    f.add((float, object), identity, on_ambiguity=on_ambiguity)
+    assert ambiguities[0]
+
+
+def test_raise_error_on_non_class():
+    f = Dispatcher('f')
+    assert raises(TypeError, lambda: f.add((1,), inc))
+
+
+def test_docstring():
+
+    def one(x, y):
+        """ Docstring number one """
+        return x + y
+
+    def two(x, y):
+        """ Docstring number two """
+        return x + y
+
+    def three(x, y):
+        return x + y
+
+    master_doc = 'Doc of the multimethod itself'
+
+    f = Dispatcher('f', doc=master_doc)
+    f.add((object, object), one)
+    f.add((int, int), two)
+    f.add((float, float), three)
+
+    assert one.__doc__.strip() in f.__doc__
+    assert two.__doc__.strip() in f.__doc__
+    assert f.__doc__.find(one.__doc__.strip()) < \
+        f.__doc__.find(two.__doc__.strip())
+    assert 'object, object' in f.__doc__
+    assert master_doc in f.__doc__
+
+
+def test_help():
+    def one(x, y):
+        """ Docstring number one """
+        return x + y
+
+    def two(x, y):
+        """ Docstring number two """
+        return x + y
+
+    def three(x, y):
+        """ Docstring number three """
+        return x + y
+
+    master_doc = 'Doc of the multimethod itself'
+
+    f = Dispatcher('f', doc=master_doc)
+    f.add((object, object), one)
+    f.add((int, int), two)
+    f.add((float, float), three)
+
+    assert f._help(1, 1) == two.__doc__
+    assert f._help(1.0, 2.0) == three.__doc__
+
+
+def test_source():
+    def one(x, y):
+        """ Docstring number one """
+        return x + y
+
+    def two(x, y):
+        """ Docstring number two """
+        return x - y
+
+    master_doc = 'Doc of the multimethod itself'
+
+    f = Dispatcher('f', doc=master_doc)
+    f.add((int, int), one)
+    f.add((float, float), two)
+
+    assert 'x + y' in f._source(1, 1)
+    assert 'x - y' in f._source(1.0, 1.0)
+
+
+def test_source_raises_on_missing_function():
+    f = Dispatcher('f')
+
+    assert raises(TypeError, lambda: f.source(1))
+
+
+def test_halt_method_resolution():
+    g = [0]
+
+    def on_ambiguity(a, b):
+        g[0] += 1
+
+    f = Dispatcher('f')
+
+    halt_ordering()
+
+    def func(*args):
+        pass
+
+    f.add((int, object), func)
+    f.add((object, int), func)
+
+    assert g == [0]
+
+    restart_ordering(on_ambiguity=on_ambiguity)
+
+    assert g == [1]
+
+    assert set(f.ordering) == {(int, object), (object, int)}
+
+
+def test_no_implementations():
+    f = Dispatcher('f')
+    assert raises(NotImplementedError, lambda: f('hello'))
+
+
+def test_register_stacking():
+    f = Dispatcher('f')
+
+    @f.register(list)
+    @f.register(tuple)
+    def rev(x):
+        return x[::-1]
+
+    assert f((1, 2, 3)) == (3, 2, 1)
+    assert f([1, 2, 3]) == [3, 2, 1]
+
+    assert raises(NotImplementedError, lambda: f('hello'))
+    assert rev('hello') == 'olleh'
+
+
+def test_dispatch_method():
+    f = Dispatcher('f')
+
+    @f.register(list)
+    def rev(x):
+        return x[::-1]
+
+    @f.register(int, int)
+    def add(x, y):
+        return x + y
+
+    class MyList(list):
+        pass
+
+    assert f.dispatch(list) is rev
+    assert f.dispatch(MyList) is rev
+    assert f.dispatch(int, int) is add
+
+
+def test_not_implemented():
+    f = Dispatcher('f')
+
+    @f.register(object)
+    def _(x):
+        return 'default'
+
+    @f.register(int)
+    def _(x):
+        if x % 2 == 0:
+            return 'even'
+        else:
+            raise MDNotImplementedError()
+
+    assert f('hello') == 'default'  # default behavior
+    assert f(2) == 'even'          # specialized behavior
+    assert f(3) == 'default'       # fall bac to default behavior
+    assert raises(NotImplementedError, lambda: f(1, 2))
+
+
+def test_not_implemented_error():
+    f = Dispatcher('f')
+
+    @f.register(float)
+    def _(a):
+        raise MDNotImplementedError()
+
+    assert raises(NotImplementedError, lambda: f(1.0))
+
+def test_ambiguity_register_error_ignore_dup():
+    f = Dispatcher('f')
+
+    class A:
+        pass
+    class B(A):
+        pass
+    class C(A):
+        pass
+
+    # suppress warning for registering ambiguous signal
+    f.add((A, B), lambda x,y: None, ambiguity_register_error_ignore_dup)
+    f.add((B, A), lambda x,y: None, ambiguity_register_error_ignore_dup)
+    f.add((A, C), lambda x,y: None, ambiguity_register_error_ignore_dup)
+    f.add((C, A), lambda x,y: None, ambiguity_register_error_ignore_dup)
+
+    # raises error if ambiguous signal is passed
+    assert raises(NotImplementedError, lambda: f(B(), C()))

rl/Lib/site-packages/sympy/multipledispatch/utils.py

@@ -0,0 +1,105 @@
+from collections import OrderedDict
+
+
+def expand_tuples(L):
+    """
+    >>> from sympy.multipledispatch.utils import expand_tuples
+    >>> expand_tuples([1, (2, 3)])
+    [(1, 2), (1, 3)]
+
+    >>> expand_tuples([1, 2])
+    [(1, 2)]
+    """
+    if not L:
+        return [()]
+    elif not isinstance(L[0], tuple):
+        rest = expand_tuples(L[1:])
+        return [(L[0],) + t for t in rest]
+    else:
+        rest = expand_tuples(L[1:])
+        return [(item,) + t for t in rest for item in L[0]]
+
+
+# Taken from theano/theano/gof/sched.py
+# Avoids licensing issues because this was written by Matthew Rocklin
+def _toposort(edges):
+    """ Topological sort algorithm by Kahn [1] - O(nodes + vertices)
+
+    inputs:
+        edges - a dict of the form {a: {b, c}} where b and c depend on a
+    outputs:
+        L - an ordered list of nodes that satisfy the dependencies of edges
+
+    >>> from sympy.multipledispatch.utils import _toposort
+    >>> _toposort({1: (2, 3), 2: (3, )})
+    [1, 2, 3]
+
+    Closely follows the wikipedia page [2]
+
+    [1] Kahn, Arthur B. (1962), "Topological sorting of large networks",
+    Communications of the ACM
+    [2] https://en.wikipedia.org/wiki/Toposort#Algorithms
+    """
+    incoming_edges = reverse_dict(edges)
+    incoming_edges = {k: set(val) for k, val in incoming_edges.items()}
+    S = OrderedDict.fromkeys(v for v in edges if v not in incoming_edges)
+    L = []
+
+    while S:
+        n, _ = S.popitem()
+        L.append(n)
+        for m in edges.get(n, ()):
+            assert n in incoming_edges[m]
+            incoming_edges[m].remove(n)
+            if not incoming_edges[m]:
+                S[m] = None
+    if any(incoming_edges.get(v, None) for v in edges):
+        raise ValueError("Input has cycles")
+    return L
+
+
+def reverse_dict(d):
+    """Reverses direction of dependence dict
+
+    >>> d = {'a': (1, 2), 'b': (2, 3), 'c':()}
+    >>> reverse_dict(d)  # doctest: +SKIP
+    {1: ('a',), 2: ('a', 'b'), 3: ('b',)}
+
+    :note: dict order are not deterministic. As we iterate on the
+        input dict, it make the output of this function depend on the
+        dict order. So this function output order should be considered
+        as undeterministic.
+
+    """
+    result = {}
+    for key in d:
+        for val in d[key]:
+            result[val] = result.get(val, ()) + (key, )
+    return result
+
+
+# Taken from toolz
+# Avoids licensing issues because this version was authored by Matthew Rocklin
+def groupby(func, seq):
+    """ Group a collection by a key function
+
+    >>> from sympy.multipledispatch.utils import groupby
+    >>> names = ['Alice', 'Bob', 'Charlie', 'Dan', 'Edith', 'Frank']
+    >>> groupby(len, names)  # doctest: +SKIP
+    {3: ['Bob', 'Dan'], 5: ['Alice', 'Edith', 'Frank'], 7: ['Charlie']}
+
+    >>> iseven = lambda x: x % 2 == 0
+    >>> groupby(iseven, [1, 2, 3, 4, 5, 6, 7, 8])  # doctest: +SKIP
+    {False: [1, 3, 5, 7], True: [2, 4, 6, 8]}
+
+    See Also:
+        ``countby``
+    """
+
+    d = {}
+    for item in seq:
+        key = func(item)
+        if key not in d:
+            d[key] = []
+        d[key].append(item)
+    return d