Python 3 deprecation fixes (including Preparing for Python 3.9) (Acad…

…emySoftwareFoundation#820)

* Added import aliasing for collections.abc module for python 3.9 support
* Created local alias for inspect.getargspec to address python 3+ deprecation warning
* Updated mutable sequence bindings to expose __next__ in compliance with PEP 3114.
* Updated collections.abc rename behavior to match six's and use collections_abc.
* Added python 3.9 to CI builds, updated python badge to match our CI builds - added 3.9 and corrected it still having 3.6 and missing 3.8.
* Updated the python 2/3 compatibility on the inspect.getargspec to match the python 3 naming rather than python 2.
* Removed python 3.9 from CI. See AcademySoftwareFoundation#828 for more context about the Python 3.9.0/pybind11 bug.

README.md

@@ -4,7 +4,7 @@ OpenTimelineIO
 ==============
 
 [![Supported VFX Platform Versions](https://img.shields.io/badge/vfx%20platform-2016--2020-lightgrey.svg)](http://www.vfxplatform.com/)
-![Supported Versions](https://img.shields.io/badge/python-2.7%2C%203.6%2C%203.7-blue.svg)
+![Supported Versions](https://img.shields.io/badge/python-2.7%2C%203.7%2C%203.8-blue.svg)
 [![Build Status](https://travis-ci.com/PixarAnimationStudios/OpenTimelineIO.svg?branch=master)](https://travis-ci.com/PixarAnimationStudios/OpenTimelineIO)
 [![codecov](https://codecov.io/gh/PixarAnimationStudios/OpenTimelineIO/branch/master/graph/badge.svg)](https://codecov.io/gh/PixarAnimationStudios/OpenTimelineIO)
 [![docs](https://readthedocs.org/projects/opentimelineio/badge/?version=latest)](https://opentimelineio.readthedocs.io/en/latest/index.html)

contrib/opentimelineio_contrib/adapters/advanced_authoring_format.py

@@ -32,7 +32,11 @@
 import sys
 import numbers
 import copy
-import collections
+try:
+    # Python 3.3+
+    import collections.abc as collections_abc
+except ImportError:
+    import collections as collections_abc
 import fractions
 import opentimelineio as otio
 
@@ -552,7 +556,7 @@ def _transcribe(item, parents, edit_rate, indent=0):
     #     elif isinstance(item, pyaaf.AxProperty):
     #         self.properties['Value'] = str(item.GetValue())
 
-    elif isinstance(item, collections.Iterable):
+    elif isinstance(item, collections_abc.Iterable):
         msg = "Creating SerializableCollection for Iterable for {}".format(
             _encoded_name(item))
         _transcribe_log(msg, indent)

src/py-opentimelineio/opentimelineio-bindings/otio_utils.h

@@ -124,7 +124,8 @@ struct MutableSequencePyAPI : public V {
 
         pybind11::class_<This::Iterator>(m, (name + "Iterator").c_str())
             .def("__iter__", &This::Iterator::iter)
-            .def("next", &This::Iterator::next);
+            .def("next", &This::Iterator::next)
+            .def("__next__", &This::Iterator::next);
 
         pybind11::class_<This>(m, name.c_str())
             .def(pybind11::init<>())

src/py-opentimelineio/opentimelineio/adapters/adapter.py

@@ -40,6 +40,13 @@
 )
 
 
+try:
+    # Python 3.0+
+    getfullargspec = inspect.getfullargspec
+except AttributeError:
+    getfullargspec = inspect.getargspec
+
+
 @core.register_type
 class Adapter(plugins.PythonPlugin):
     """Adapters convert between OTIO and other formats.
@@ -307,7 +314,7 @@ def plugin_info_map(self):
                 for fn_name in _FEATURE_MAP[feature]:
                     if hasattr(self.module(), fn_name):
                         fn = getattr(self.module(), fn_name)
-                        args = inspect.getargspec(fn)
+                        args = getfullargspec(fn)
                         docs = inspect.getdoc(fn)
                         break
 

src/py-opentimelineio/opentimelineio/core/_core_utils.py

@@ -1,5 +1,9 @@
 import types
-import collections
+try:
+    # Python 3.3+
+    import collections.abc as collections_abc
+except ImportError:
+    import collections as collections_abc
 import copy
 import sys
 
@@ -46,7 +50,7 @@ def _xrange(*args):
 
 
 def _is_nonstring_sequence(v):
-    return isinstance(v, collections.Sequence) and not _is_str(v)
+    return isinstance(v, collections_abc.Sequence) and not _is_str(v)
 
 
 def _value_to_any(value, ids=None):
@@ -55,7 +59,7 @@ def _value_to_any(value, ids=None):
 
     if isinstance(value, SerializableObject):
         return PyAny(value)
-    if isinstance(value, collections.Mapping):
+    if isinstance(value, collections_abc.Mapping):
         if ids is None:
             ids = set()
         d = AnyDictionary()
@@ -88,7 +92,7 @@ def _value_to_any(value, ids=None):
 
 
 def _value_to_so_vector(value, ids=None):
-    if not isinstance(value, collections.Sequence) or _is_str(value):
+    if not isinstance(value, collections_abc.Sequence) or _is_str(value):
         raise TypeError(
             "Expected list/sequence of SerializableObjects;"
             " found type '{}'".format(type(value))
@@ -150,13 +154,13 @@ def __deepcopy__(self, memo):
         )
         return m
 
-    collections.MutableMapping.register(mapClass)
+    collections_abc.MutableMapping.register(mapClass)
     mapClass.__setitem__ = __setitem__
     mapClass.__str__ = __str__
     mapClass.__repr__ = __repr__
 
     seen = set()
-    for klass in (collections.MutableMapping, collections.Mapping):
+    for klass in (collections_abc.MutableMapping, collections_abc.Mapping):
         for name in klass.__dict__.keys():
             if name in seen:
                 continue
@@ -217,15 +221,15 @@ def __setitem__(self, index, item):
         if not isinstance(index, slice):
             self.__internal_setitem__(index, conversion_func(item))
         else:
-            if not isinstance(item, collections.Iterable):
+            if not isinstance(item, collections_abc.Iterable):
                 raise TypeError("can only assign an iterable")
 
             indices = range(*index.indices(len(self)))
 
             if index.step in (1, None):
                 if (
                         not side_effecting_insertions
-                        and isinstance(item, collections.MutableSequence)
+                        and isinstance(item, collections_abc.MutableSequence)
                         and len(item) == len(indices)
                 ):
                     for i0, i in enumerate(indices):
@@ -254,7 +258,7 @@ def __setitem__(self, index, item):
                             self.extend(cached_items)
                             raise e
             else:
-                if not isinstance(item, collections.Sequence):
+                if not isinstance(item, collections_abc.Sequence):
                     raise TypeError("can only assign a sequence")
                 if len(item) != len(indices):
                     raise ValueError(
@@ -292,7 +296,7 @@ def insert(self, index, item):
             if conversion_func else item
         )
 
-    collections.MutableSequence.register(sequenceClass)
+    collections_abc.MutableSequence.register(sequenceClass)
     sequenceClass.__radd__ = __radd__
     sequenceClass.__add__ = __add__
     sequenceClass.__getitem__ = __getitem__
@@ -303,7 +307,7 @@ def insert(self, index, item):
     sequenceClass.__repr__ = __repr__
 
     seen = set()
-    for klass in (collections.MutableSequence, collections.Sequence):
+    for klass in (collections_abc.MutableSequence, collections_abc.Sequence):
         for name in klass.__dict__.keys():
             if name not in seen:
                 seen.add(name)