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awkwardduet 1.1a2

Lib3to2 maintenance fork. Lib3to2 is a set of fixers and utilities forlib2to3, a source code transformer included in Python standard library.

Lib3to2 began as Google Summer of Code (GSOC) 2009 project by Joe Amenta. Lib3to2 is a set of fixers and utilities for lib2to3, a source code transformer included in Python standard library.

Porting from Python 3 to Python 2 codebase is often easier, because there’s less ambiguity due to stricter rules that Python 3 imposes. Lib3to2 is crucial in enabling the developer to start enjoying modern Python environment, while still maintaining compatibility with older runtimes.

Feedback

If you plan or would like to port your Python 3 code to Python 2 we encourage you to run 3to2 and report any issues with the transformation. Your experience with using this library is very valuable in shaping the future goals of this project.

A great way to influence the project schedule is to use the “It’s affecting me” and “It’s affecting project” feedback mechanisms.

Usage

Run "./3to2" to convert stdin ("-"), files or directories given as arguments. By default, the tool outputs a unified diff-formatted patch on standard output and a "what was changed" summary on standard error, but the "-w" option can be given to write back converted files, creating ".bak"-named backup files.

Changelog

awkwardduet 1.1a2

Snapshot of new features and bugfixes.

Bug Fixes

  • fix_kwargs no longer breaks docstrings when adding code to fix parameters. (Denis Zawada, #880389)

New Features

  • Format template strings, that use auto-numbered fields, are now converted to use explicitly numbered fields, thus extending compatibility with Python 2.6 even further. (Denis Zawada, #881113)
  • Chained exceptions (raise E from E) are now included in the __cause__ attribute whenever possible. (Denis Zawada, #881136)
  • Function annotations are now collected and set manually. You can access them via the func_annotations property, exactly like in Python 3. (Denis Zawada, #881134)
  • New fixer fix_funcdecorator, fix_classdecorator equivalent for decorated functions, is now available and auto-enabled (as a dependency for fix_annotations) (Denis Zawada)

Other

  • __annotations__ attributes are now renamed to func_annotations.
  • Attribute renamers with special names (e.g. __nonzero__) are now more eager.
  • Method renamers have been DRYed and marked as BM_compatible.
  • Some minor issues with preserving whitespace in fix_classdecorator have been resolved by switching to new implementation, that could be reused.
  • Fix_str have been split into fix_str and fix_str_literals. This has allowed to mark fix_str_literals as BM_compatible and shaved off almost 2 seconds from the test suite run.

awkwardduet 1.1a1

First maintenance release of awkwardduet, a maintenance fork of lib3to2. The release focus is on fixing major issues reported in lib3to2 1.0 series.

Bug Fixes

  • fix_super now refactors magic super (super() with no arguments) by searching the parsing tree for class name and the first argument, the same mechanism used by Python 3 runtime. Until now super() used self.__class__ instead of a class name, which caused trouble with non-trivial inheritence. (Denis Zawada, #880377; originally reported in lib3to2 1.0 series)
  • fix_next now correctly parenthesizes generator statements. (Denis Zawada, #880378)
  • fix_next is now aware of extend form of the next builting, i.e next(iterable[, default]). If extended signature is detected, a warning is reported and the code remains unaltered. This provides compatibility with Python 2.6–7. (Denis Zawada, #880383)

New Features

  • Python 3 __str__ methods are now converted to __unicode__ in Python 2, while __bytes__ are converted to __str__. This further extends unicode compatibility between runtimes. (Denis Zawada, #880382)
  • Python 3 default absolute import behavior is now enforced in Python 2.5–7 using the ‘from __future__ import __absolute_import__’ directive. (Denis Zawada, #880388)

Other

  • Testing infrastructure is now compatible with nose runner. (Denis Zawada)

3to2 0.1–1.0

Less recent changes can be found in the NEWS.rst file in the top-level source code directory.