Changelog

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0.23.0 (not yet released)

• Drop support for Python 3.7, which reached end of life on 2023-06-27.

  Bidict may still be compatible with 3.7, but as it is no longer tested with 3.7, compatibility is not guaranteed.

0.22.1 (2022-12-31)

• Only include the source code in the source distribution. This reduces the size of the source distribution from ~200kB to ~30kB.

• Fix the return type hint of bidict.inverted() to return an Iterator, rather than an Iterable.

0.22.0 (2022-03-23)

• Drop support for Python 3.6, which reached end of life on 2021-12-23 and is no longer supported by pip as of pip version 22. Take advantage of this to reduce bidict’s maintenance costs.

• Use mypy-appeasing explicit re-exports in __init__.py (e.g. import x as x) so that mypy no longer gives you an implicit re-export error if you run it with --no-implicit-reexport (or --strict) against code that imports from bidict.

• Update the implementations and type annotations of bidict.BidictBase.keys() and bidict.BidictBase.values() to make use of the new BidictKeysView type, which works a bit better with type checkers.

• Inverse bidict instances are now computed lazily the first time the inverse attribute is accessed rather than being computed eagerly during initialization. (A bidict’s backing, inverse, one-way mapping is still kept in sync eagerly as any mutations are made, to preserve key- and value-uniqueness.)

• Optimize initializing a bidict with another bidict. In a microbenchmark on Python 3.10, this now performs over 2x faster.

• Optimize updating an empty bidict with another bidict. In a microbenchmark on Python 3.10, this now performs 60-75% faster.

• Optimize copy(). In a microbenchmark on Python 3.10, this now performs 10-20x faster.

• Optimize rolling back failed updates to a bidict in the case that the number of items passed to the update call can be determined to be larger than the bidict being updated. Previously this rollback was O(n) in the number of items passed. Now it is O(1), i.e. unboundedly faster.

• Optimize bidict.BidictBase.__contains__() (the method called when you run key in mybidict). In a microbenchmark on Python 3.10, this now performs over 3-10x faster in the False case, and at least 50% faster in the True case.

• Optimize bidict.BidictBase.__eq__() (the method called when you run mybidict == other). In a microbenchmark on Python 3.10, this now performs 15-25x faster for ordered bidicts, and 7-12x faster for unordered bidicts.

• Optimize equals_order_sensitive(). In a microbenchmark on Python 3.10, this now performs 2x faster for ordered bidicts and 60-90% faster for unordered bidicts.

• Optimize the MappingView objects returned by bidict.OrderedBidict.keys(), bidict.OrderedBidict.values(), and bidict.OrderedBidict.items() to delegate to backing dict_keys and dict_items objects if available, which are much faster in CPython. For example, in a microbenchmark on Python 3.10, orderedbi.items() == d.items() now performs 30-50x faster.

• Fix a bug where bidict.BidictBase.__eq__() was always returning False rather than NotImplemented in the case that the argument was not a Mapping, defeating the argument’s own __eq__() if implemented. As a notable example, bidicts now correctly compare equal to unittest.mock.ANY.

• bidict.BidictBase now adds a __reversed__ implementation to subclasses that don’t have an overridden implementation depending on whether both their backing mappings are Reversible. Previously, a __reversed__ implementation was only added to BidictBase when BidictBase._fwdm_cls was Reversible. So if a BidictBase subclass set its _fwdm_cls to a non-reversible mutable mapping, it would also have to manually set its __reversed__ attribute to None to override the implementation inherited from BidictBase. This is no longer necessary thanks to bidict’s new object.__init_subclass__() logic.

• The MappingView objects returned by bidict.OrderedBidict.keys(), bidict.OrderedBidict.values(), and bidict.OrderedBidict.items() are now Reversible. (This was already the case for unordered bidicts when running on Python 3.8+.)

• Add support for Python 3.9-style dict merge operators (PEP 584).

  See the tests for examples.

• Update docstrings for bidict.BidictBase.keys(), bidict.BidictBase.values(), and bidict.BidictBase.items() to include more details.

• namedbidict() now exposes the passed-in keyname and valname in the corresponding properties on the generated class.

• namedbidict() now requires base_type to be a subclass of BidictBase, but no longer requires base_type to provide an _isinv attribute, which BidictBase subclasses no longer provide.

• When attempting to pickle a bidict’s inverse whose class was dynamically generated, and no reference to the dynamically-generated class has been stored anywhere in sys.modules where pickle can find it, the pickle call is now more likely to succeed rather than failing with a PicklingError.

• Remove the use of slots from (non-ABC) bidict types.

  This better matches the mapping implementations in Python’s standard library, and significantly reduces code complexity and maintenance burden. The memory savings conferred by using slots are not noticeable unless you’re creating millions of bidict instances anyway, which is an extremely unusual usage pattern.

  Of course, bidicts can still contain millions (or more) items (which is not an unusual usage pattern) without using any more memory than before these changes. Notably, slots are still used in the internal linked list nodes of ordered bidicts to save memory, since as many node instances are created as there are items inserted.

0.21.4 (2021-10-23)

Explicitly declare support for Python 3.10 as well as some minor internal improvements.

0.21.3 (2021-09-05)

• All bidicts now provide the equals_order_sensitive() method, not just OrderedBidicts.

  Since support for Python < 3.6 was dropped in v0.21.0, dicts provide a deterministic ordering on all supported Python versions, and as a result, all bidicts do too. So now even non-Ordered bidicts might as well provide equals_order_sensitive().

  See the updated What about order-preserving dicts? docs for more info.

• Take better advantage of the fact that dicts became reversible in Python 3.8.

  Specifically, now even non-Ordered bidicts provide a __reversed__() implementation on Python 3.8+ that calls reversed() on the backing _fwdm mapping.

  As a result, if you are using Python 3.8+, frozenbidict now gives you everything that FrozenOrderedBidict gives you, but with less space overhead.

• Drop setuptools_scm as a setup_requires dependency.

• Remove the bidict.__version_info__ attribute.

0.21.2 (2020-09-07)

• Include py.typed file to mark bidict as type hinted.

0.21.1 (2020-09-07)

This release was yanked and replaced with the 0.21.2 release, which actually provides the intended changes.

0.21.0 (2020-08-22)

• bidict now provides type hints! ⌨️ ✅

  Adding type hints to bidict poses particularly interesting challenges due to the combination of generic types, dynamically-generated types (such as inverse bidict classes and namedbidicts), and complicating optimizations such as the use of slots and weakrefs.

  It didn’t take long to hit bugs and missing features in the state of the art for type hinting in Python today, e.g. missing higher-kinded types support (python/typing#548), too-narrow type hints for collections.abc.Mapping (python/typeshed#4435), a typing.Generic bug in Python 3.6 (BPO-41451), etc.

  That said, this release should provide a solid foundation for code using bidict that enables static type checking.

  As always, if you spot any opportunities to improve bidict (including its new type hints), please don’t hesitate to submit a PR!

• Add bidict.MutableBidirectionalMapping ABC.

  The Bidict Types Diagram has been updated accordingly.

• Drop support for Python 3.5, which reaches end of life on 2020-09-13, represents a tiny percentage of bidict downloads on PyPI Stats, and lacks support for variable type hint syntax, ordered dicts, and object.__init_subclass__.

• Remove the no-longer-needed bidict.compat module.

• Move inverse bidict class access from a property to an attribute set in __init_subclass__, to save function call overhead on repeated access.

• bidict.OrderedBidictBase.__iter__() no longer accepts a reverse keyword argument so that it matches the signature of container.__iter__().

• Set the __module__ attribute of various bidict types (using sys._getframe() when necessary) so that private, internal modules are not exposed e.g. in classes’ repr strings.

• namedbidict() now immediately raises TypeError if the provided base_type does not provide _isinv or __getstate__(), rather than succeeding with a class whose instances may raise AttributeError when these attributes are accessed.

0.20.0 (2020-07-23)

The following breaking changes are expected to affect few if any users.

Remove APIs deprecated in the previous release:

• bidict.OVERWRITE and bidict.IGNORE.

• The on_dup_key, on_dup_val, and on_dup_kv arguments of put() and putall().

• The on_dup_key, on_dup_val, and on_dup_kv bidict class attributes.

• Remove bidict.BidirectionalMapping.__subclasshook__() due to lack of use and maintenance cost.

  Fixes a bug introduced in 0.15.0 that caused any class with an inverse attribute to be incorrectly considered a subclass of collections.abc.Mapping. #111

0.19.0 (2020-01-09)

• Drop support for Python 2 as promised in v0.18.2.

  The bidict.compat module has been pruned accordingly.

  This makes bidict more efficient on Python 3 and enables further improvement to bidict in the future.

• Deprecate bidict.OVERWRITE and bidict.IGNORE. A UserWarning will now be emitted if these are used.

  bidict.DROP_OLD and bidict.DROP_NEW should be used instead.

• Rename DuplicationPolicy to OnDupAction (and implement it via an Enum).

  An OnDupAction may be one of RAISE, DROP_OLD, or DROP_NEW.

• Expose the new OnDup class to contain the three OnDupActions that should be taken upon encountering the three kinds of duplication that can occur (key, val, kv).

• Provide the ON_DUP_DEFAULT, ON_DUP_RAISE, and ON_DUP_DROP_OLD OnDup convenience instances.

• Deprecate the on_dup_key, on_dup_val, and on_dup_kv arguments of put() and putall(). A UserWarning will now be emitted if these are used.

  These have been subsumed by the new on_dup argument, which takes an OnDup instance.

  Use it like this: bi.put(1, 2, OnDup(key=RAISE, val=...)). Or pass one of the instances already provided, such as ON_DUP_DROP_OLD. Or just don’t pass an on_dup argument to use the default value of ON_DUP_RAISE.

  The Values Must Be Unique docs have been updated accordingly.

• Deprecate the on_dup_key, on_dup_val, and on_dup_kv bidict class attributes. A UserWarning will now be emitted if these are used.

  These have been subsumed by the new on_dup class attribute, which takes an OnDup instance.

  See the updated Extending bidict docs for example usage.

• Improve the more efficient implementations of keys(), values(), and items(), and now also provide a more efficient implementation of __iter__() by delegating to backing dicts in the bidict types for which this is possible.

• Move bidict.BidictBase.values() to bidict.BidirectionalMapping.values(), since the implementation is generic.

• No longer use __all__ in bidict’s __init__.py.

0.18.4 (2020-11-02)

• Backport fix from v0.20.0 that removes bidict.BidirectionalMapping.__subclasshook__() due to lack of use and maintenance cost.

0.18.3 (2019-09-22)

• Improve validation of names passed to namedbidict(): Use str.isidentifier() on Python 3, and a better regex on Python 2.

• On Python 3, set __qualname__ on namedbidict() classes based on the provided typename argument.

0.18.2 (2019-09-08)

• Warn that Python 2 support will be dropped in a future release when Python 2 is detected.

0.18.1 (2019-09-03)

• Fix a regression introduced by the memory optimizations added in 0.15.0 which caused deepcopied and unpickled bidicts to have their inverses set incorrectly. #94

0.18.0 (2019-02-14)

• Rename bidict.BidirectionalMapping.inv to inverse and make bidict.BidictBase.inv an alias for inverse. #86

• bidict.BidirectionalMapping.__subclasshook__() now requires an inverse attribute rather than an inv attribute for a class to qualify as a virtual subclass. This breaking change is expected to affect few if any users.

• Add Python 2/3-compatible bidict.compat.collections_abc alias.

• Stop testing Python 3.4 on CI, and warn when Python 3 < 3.5 is detected rather than Python 3 < 3.3.

  Python 3.4 reaches end of life on 2019-03-18. As of January 2019, 3.4 represents only about 3% of bidict downloads on PyPI Stats.

0.17.5 (2018-11-19)

Improvements to performance and delegation logic, with minor breaking changes to semi-private APIs.

• Remove the __delegate__ instance attribute added in the previous release. It was overly general and not worth the cost.

  Instead of checking self.__delegate__ and delegating accordingly each time a possibly-delegating method is called, revert back to using “delegated-to-fwdm” mixin classes (now found in bidict._delegating_mixins), and resurrect a mutable bidict parent class that omits the mixins as bidict.MutableBidict.

• Rename __repr_delegate__ to _repr_delegate.

0.17.4 (2018-11-14)

Minor code, interop, and (semi-)private API improvements.

• OrderedBidict optimizations and code improvements.

  Use bidicts for the backing _fwdm and _invm mappings, obviating the need to store key and value data in linked list nodes.

• Refactor proxied- (i.e. delegated-) to-_fwdm logic for better composability and interoperability.

  Drop the _Proxied* mixin classes and instead move their methods into BidictBase, which now checks for an object defined by the BidictBase.__delegate__ attribute. The BidictBase.__delegate__ object will be delegated to if the method is available on it, otherwise a default implementation (e.g. inherited from Mapping) will be used otherwise. Subclasses may set __delegate__ = None to opt out.

  Consolidate _MutableBidict into bidict.bidict now that the dropped mixin classes make it unnecessary.

• Change __repr_delegate__ to simply take a type like dict or list.

• Upgrade to latest major sortedcontainers version (from v1 to v2) for the SortedBidict Recipes.

• bidict.compat.{view,iter}{keys,values,items} on Python 2 no longer assumes the target object implements these methods, as they’re not actually part of the Mapping interface, and provides fallback implementations when the methods are unavailable. This allows the SortedBidict Recipes to continue to work with sortedcontainers v2 on Python 2.

0.17.3 (2018-09-18)

• Improve packaging by adding a pyproject.toml and by including more supporting files in the distribution. #81

• Drop pytest-runner and support for running tests via python setup.py test in preference to pytest or python -m pytest.

0.17.2 (2018-04-30)

Memory usage improvements

• Use less memory in the linked lists that back OrderedBidicts by storing node data unpacked rather than in (key, value) tuple objects.

0.17.1 (2018-04-28)

Bugfix Release

Fix a regression in 0.17.0 that could cause erroneous behavior when updating items of an Orderedbidict’s inverse, e.g. some_ordered_bidict.inv[foo] = bar.

0.17.0 (2018-04-25)

Speedups and memory usage improvements

• Pass keys(), values(), and items() calls (as well as their iter* and view* counterparts on Python 2) through to the backing _fwdm and _invm dicts so that they run as fast as possible (i.e. at C speed on CPython), rather than using the slower implementations inherited from collections.abc.Mapping.

• Use weakrefs in the linked lists that back OrderedBidicts to avoid creating strong reference cycles.

  Memory for an ordered bidict that you create can now be reclaimed in CPython as soon as you no longer hold any references to it, rather than having to wait until the next garbage collection. #71

Misc

• Add bidict.__version_info__ attribute to complement bidict.__version__.

0.16.0 (2018-04-06)

Minor code and efficiency improvements to inverted() and bidict._iter._iteritems_args_kw (formerly bidict.pairs()).

Minor Breaking API Changes

The following breaking changes are expected to affect few if any users.

• Rename bidict.pairs() → bidict._iter._iteritems_args_kw.

0.15.0 (2018-03-29)

Speedups and memory usage improvements

• Use __slots__ to speed up bidict attribute access and reduce memory usage. On Python 3, instantiating a large number of bidicts now uses ~57% the amount of memory that it used before, and on Python 2 only ~33% the amount of memory that it used before, in a simple but representative benchmark.

• Use weakrefs to refer to a bidict’s inverse internally, no longer creating a strong reference cycle. Memory for a bidict that you create can now be reclaimed in CPython as soon as you no longer hold any references to it, rather than having to wait for the next garbage collection. See the new bidict Avoids Reference Cycles documentation. #24

• Make bidict.BidictBase.__eq__() significantly more speed- and memory-efficient when comparing to a non-dict Mapping. (Mapping.__eq__()'s inefficient implementation will now never be used.) The implementation is now more reusable as well.

• Make bidict.OrderedBidictBase.__iter__() as well as equality comparison slightly faster for ordered bidicts.

Minor Bugfixes

• namedbidict() now verifies that the provided keyname and valname are distinct, raising ValueError if they are equal.

• namedbidict() now raises TypeError if the provided base_type is not a BidirectionalMapping.

• If you create a custom bidict subclass whose _fwdm_cls differs from its _invm_cls (as in the FwdKeySortedBidict example from the SortedBidict Recipes), the inverse bidirectional mapping type (with _fwdm_cls and _invm_cls swapped) is now correctly computed and used automatically for your custom bidict’s inverse bidict.

Misc

• Classes no longer have to provide an __inverted__ attribute to be considered virtual subclasses of BidirectionalMapping.

• If bidict.inverted() is passed an object with an __inverted__ attribute, it now ensures it is callable() before returning the result of calling it.

• __repr__() no longer checks for a __reversed__ method to determine whether to use an ordered or unordered-style repr. It now calls the new __repr_delegate__ instead (which may be overridden if needed), for better composability.

Minor Breaking API Changes

The following breaking changes are expected to affect few if any users.

• Split back out the BidictBase class from frozenbidict and OrderedBidictBase from FrozenOrderedBidict, reverting the merging of these in 0.14.0. Having e.g. issubclass(bidict, frozenbidict) == True was confusing, so this change restores issubclass(bidict, frozenbidict) == False.

  See the updated Bidict Types Diagram and Polymorphism documentation.

• Rename:

  • bidict.BidictBase.fwdm → ._fwdm

  • bidict.BidictBase.invm → ._invm

  • bidict.BidictBase.fwd_cls → ._fwdm_cls

  • bidict.BidictBase.inv_cls → ._invm_cls

  • bidict.BidictBase.isinv → ._isinv

  Though overriding _fwdm_cls and _invm_cls remains supported (see Extending bidict), this is not a common enough use case to warrant public names. Most users do not need to know or care about any of these.

• The RAISE, OVERWRITE, and IGNORE duplication policies are no longer available as attributes of DuplicationPolicy, and can now only be accessed as attributes of the bidict module namespace, which was the canonical way to refer to them anyway. It is now no longer possible to create an infinite chain like DuplicationPolicy.RAISE.RAISE.RAISE...

• Make bidict.pairs() and bidict.inverted() no longer importable from bidict.util, and now only importable from the top-level bidict module. (bidict.util was renamed bidict._util.)

• Pickling ordered bidicts now requires at least version 2 of the pickle protocol. If you are using Python 3, pickle.DEFAULT_PROTOCOL is 3 anyway, so this will not affect you. However if you are using in Python 2, DEFAULT_PROTOCOL is 0, so you must now explicitly specify the version in your pickle.dumps() calls, e.g. pickle.dumps(ob, 2).

0.14.2 (2017-12-06)

• Make initializing (or updating an empty bidict) from only another BidirectionalMapping more efficient by skipping unnecessary duplication checking.

• Fix accidental ignoring of specified base_type argument when (un)pickling a namedbidict().

• Fix incorrect inversion of some_named_bidict.inv.<fwdname>_for and some_named_bidict.inv.<invname>_for.

• Only warn when an unsupported Python version is detected (e.g. Python < 2.7) rather than raising AssertionError.

0.14.1 (2017-11-28)

• Fix a bug introduced in 0.14.0 where hashing a frozenbidict’s inverse (e.g. f = frozenbidict(); {f.inv: '...'}) would cause an AttributeError.

• Fix a bug introduced in 0.14.0 for Python 2 users where attempting to call viewitems() would cause a TypeError. #48

0.14.0 (2017-11-20)

• Fix a bug where bidict’s default on_dup_kv policy was set to RAISE, rather than matching whatever on_dup_val policy was in effect as was documented.

• Fix a bug that could happen when using Python’s optimization (-O) flag that could leave an ordered bidict in an inconsistent state when dealing with duplicated, overwritten keys or values. If you do not use optimizations (specifically, skipping assert statements), this would not have affected you.

• Fix a bug introduced by the optimizations in 0.13.0 that could cause a frozen bidict that compared equal to another mapping to have a different hash value from the other mapping, violating Python’s object model. This would only have affected you if you were inserting a frozen bidict and some other immutable mapping that it compared equal to into the same set or mapping.

• Add equals_order_sensitive().

• Reduce the memory usage of ordered bidicts.

• Make copying of ordered bidicts faster.

• Improvements to tests and CI, including:

  • Test on Windows

  • Test with PyPy3

  • Test with CPython 3.7-dev

  • Test with optimization flags

  • Require pylint to pass

Breaking API Changes

This release includes multiple API simplifications and improvements.

• Rename:

  • orderedbidict → OrderedBidict

  • frozenorderedbidict → FrozenOrderedBidict

  so that these now match the case of collections.OrderedDict.

  The names of the bidict, namedbidict(), and frozenbidict classes have been retained as all-lowercase so that they continue to match the case of dict, namedtuple(), and frozenset, respectively.

• The ON_DUP_VAL duplication policy value for on_dup_kv has been removed. Use None instead.

• Merge frozenbidict and BidictBase together and remove BidictBase. frozenbidict is now the concrete base class that all other bidict types derive from. See the updated Bidict Types Diagram.

• Merge frozenbidict and FrozenBidictBase together and remove FrozenBidictBase. See the updated Bidict Types Diagram.

• Merge frozenorderedbidict and OrderedBidictBase together into a single FrozenOrderedBidict class and remove OrderedBidictBase. OrderedBidict now extends FrozenOrderedBidict to add mutable behavior. See the updated Bidict Types Diagram.

• Make __eq__() always perform an order-insensitive equality test, even if the other mapping is ordered.

  Previously, __eq__() was only order-sensitive for other OrderedBidictBase subclasses, and order-insensitive otherwise.

  Use the new equals_order_sensitive() method for order-sensitive equality comparison.

• orderedbidict._should_compare_order_sensitive() has been removed.

• frozenorderedbidict._HASH_NITEMS_MAX has been removed. Since its hash value must be computed from all contained items (so that hash results are consistent with equality comparisons against unordered mappings), the number of items that influence the hash value should not be limitable.

• frozenbidict._USE_ITEMSVIEW_HASH has been removed, and frozenbidict.compute_hash() now uses collections.ItemsView._hash() to compute the hash always, not just when running on PyPy.

  Override frozenbidict.compute_hash() to return hash(frozenset(iteritems(self))) if you prefer the old default behavior on CPython, which takes linear rather than constant space, but which uses the frozenset_hash routine (implemented in setobject.c) rather than the pure Python ItemsView._hash() routine.

• loosebidict and looseorderedbidict have been removed. A simple recipe to implement equivalents yourself is now given in Extending bidict.

• Rename FrozenBidictBase._compute_hash() → frozenbidict.compute_hash().

• Rename DuplicationBehavior → DuplicationPolicy.

• Rename:

  • BidictBase._fwd_class → .fwd_cls

  • BidictBase._inv_class → .inv_cls

  • BidictBase._on_dup_key → on_dup_key

  • BidictBase._on_dup_val → on_dup_val

  • BidictBase._on_dup_kv → on_dup_kv

0.13.1 (2017-03-15)

• Fix regression introduced by the new __subclasshook__() functionality in 0.13.0 so that issubclass(OldStyleClass, BidirectionalMapping) once again works with old-style classes, returning False rather than raising AttributeError #41

0.13.0 (2017-01-19)

• Support Python 3.6.

  (Earlier versions of bidict should work fine on 3.6, but it is officially supported starting in this version.)

• BidirectionalMapping has been refactored into an abstract base class, following the way collections.abc.Mapping works. The concrete method implementations it used to provide have been moved into a new BidictBase subclass.

  BidirectionalMapping now also implements __subclasshook__(), so any class that provides a conforming set of attributes (enumerated in _subclsattrs) will be considered a BidirectionalMapping subclass automatically.

• OrderedBidirectionalMapping has been renamed to OrderedBidictBase, to better reflect its function. (It is not an ABC.)

• A new FrozenBidictBase class has been factored out of frozenbidict and frozenorderedbidict. This implements common behavior such as caching the result of __hash__ after the first call.

• The hash implementations of frozenbidict and frozenorderedbidict. have been reworked to improve performance and flexibility. frozenorderedbidict’s hash implementation is now order-sensitive.

  See frozenbidict._compute_hash() and frozenorderedbidict._compute_hash for more documentation of the changes, including the new frozenbidict._USE_ITEMSVIEW_HASH and frozenorderedbidict._HASH_NITEMS_MAX attributes. If you have an interesting use case that requires overriding these, or suggestions for an alternative implementation, please share your feedback.

• Add _fwd_class and _inv_class attributes representing the backing Mapping types used internally to store the forward and inverse dictionaries, respectively.

  This allows creating custom bidict types with extended functionality simply by overriding these attributes in a subclass.

  See the new Extending bidict documentation for examples.

• Pass any parameters passed to popitem() through to _fwd.popitem for greater extensibility.

• More concise repr strings for empty bidicts.

  e.g. bidict() rather than bidict({}) and orderedbidict() rather than orderedbidict([]).

• Add bidict.compat.PYPY and remove unused bidict.compat.izip_longest.

0.12.0 (2016-07-03)

• New/renamed exceptions:

  • KeyDuplicationError

  • ValueDuplicationError

  • KeyAndValueDuplicationError

  • DuplicationError (base class for the above)

• put() now accepts on_dup_key, on_dup_val, and on_dup_kv keyword args which allow you to override the default policy when the key or value of a given item duplicates any existing item’s. These can take the following values:

  • RAISE

  • OVERWRITE

  • IGNORE

  on_dup_kv can also take ON_DUP_VAL.

  If not provided, put() uses the RAISE policy by default.

• New putall() method provides a bulk put() API, allowing you to override the default duplication handling policy that update() uses.

• update() now fails clean, so if an update() call raises a DuplicationError, you can now be sure that none of the given items was inserted.

  Previously, all of the given items that were processed before the one causing the failure would have been inserted, and no facility was provided to recover which items were inserted and which weren’t, nor to revert any changes made by the failed update() call. The new behavior makes it easier to reason about and control the effects of failed update() calls.

  The new putall() method also fails clean.

  Internally, this is implemented by storing a log of changes made while an update is being processed, and rolling back the changes when one of them is found to cause an error. This required reimplementing orderedbidict on top of two dicts and a linked list, rather than two OrderedDicts, since OrderedDict does not expose its backing linked list.

• orderedbidict.move_to_end() now works on Python < 3.2 as a result of the new orderedbidict implementation.

• Add

  • bidict.compat.viewkeys

  • bidict.compat.viewvalues

  • bidict.compat.iterkeys

  • bidict.compat.itervalues

  • bidict.compat.izip

  • bidict.compat.izip_longest

  to complement the existing bidict.compat.iteritems and bidict.compat.viewitems compatibility helpers.

• More efficient implementations of bidict.pairs(), inverted(), and copy().

• Implement __copy__() for use with the copy module.

• Fix issue preventing a client class from inheriting from loosebidict. #34

• Add benchmarking to tests.

• Drop official support for CPython 3.3. (It may continue to work, but is no longer being tested.)

Breaking API Changes

• Rename KeyExistsException → KeyDuplicationError and ValueExistsException → ValueDuplicationError.

• When overwriting the key of an existing value in an orderedbidict, the position of the existing item is now preserved, overwriting the key of the existing item in place, rather than moving the item to the end. This now matches the behavior of overwriting the value of an existing key, which has always preserved the position of the existing item. (If inserting an item whose key duplicates that of one existing item and whose value duplicates that of another, the existing item whose value is duplicated is still dropped, and the existing item whose key is duplicated still gets its value overwritten in place, as before.)

  For example:

  o = orderedbidict([(0, 1), (2, 3)])
  o.forceput(4, 1)
  

  previously would have resulted in:

  orderedbidict([(2, 3), (4, 1)])
  

  but now results in:

  orderedbidict([(4, 1), (2, 3)])
  

0.11.0 (2016-02-05)

• Add orderedbidict, looseorderedbidict, and frozenorderedbidict.

• Add Code of Conduct.

• Drop official support for pypy3. (It still may work but is no longer being tested. Support may be added back once pypy3 has made more progress.)

0.10.0.post1 (2015-12-23)

• Minor documentation fixes and improvements.

0.10.0 (2015-12-23)

• Remove several features in favor of keeping the API simpler and the code more maintainable.

• In the interest of protecting data safety more proactively, by default bidict now raises an error on attempting to insert a non-unique value, rather than allowing its associated key to be silently overwritten. See discussion in #21.

• New forceupdate() method provides a bulk forceput() operation.

• Fix bugs in pop and setdefault which could leave a bidict in an inconsistent state.

Breaking API Changes

• Remove bidict.__invert__, and with it, support for the ~b syntax. Use inv instead. #19

• Remove support for the slice syntax. Use b.inv[val] rather than b[:val]. #19

• Remove bidict.invert. Use inv rather than inverting a bidict in place. #20

• Raise ValueExistsException when attempting to insert a mapping with a non-unique key. #21

• Rename collapsingbidict → loosebidict now that it suppresses ValueExistsException rather than the less general CollapseException. #21

• CollapseException has been subsumed by ValueExistsException. #21

• put() now raises KeyExistsException when attempting to insert an already-existing key, and ValueExistsException when attempting to insert an already-existing value.

0.9.0.post1 (2015-06-06)

• Fix metadata missing in the 0.9.0rc0 release.

0.9.0rc0 (2015-05-30)

• Add this changelog, Contributors’ Guide, Gitter chat room, and other community-oriented improvements.

• Adopt Pytest.

• Add property-based tests via hypothesis.

• Other code, tests, and docs improvements.

Breaking API Changes

• Move bidict.iteritems() and bidict.viewitems() to new bidict.compat module.

• Move bidict.inverted to new bidict.util module (still available from top-level bidict module as well).

• Move bidict.fancy_iteritems() → bidict.util.pairs() (also available from top level as bidict.pairs()).

• Rename bidict.namedbidict()'s bidict_type argument → base_type.