0.5.0b0

What's Changed

Major

This release includes the overhaul of our action system, and with the next release we will be starting deprecating the old ones. A list
of changes:

• refactor.core no longer contains any actions (the deprecated aliases are still imported and exposed but all the new actions go into refactor.actions)
• Action is now split into two, a refactor.actions.BaseAction which is the base of all actions (useful for type hinting) and a refactor.actions.LazyReplace (a replace action that builds the node lazily in its build()).
• ReplacementAction is now refactor.actions.Replace
• NewStatementAction is now refactor.actions.LazyInsertAfter
• TargetedNewStatementAction is now refactor.actions.InsertAfter

For migrating your code base to the new style actions, we wrote a small tool (that we also used internally), examples/deprecated_aliases.py. Feel free to try it, and let us know if the transition was seamless.

Other Changes

• Added experimental Windows support, contributed by Hakan Celik
• common.find_closest now takes end_lineno and end_col_offset into account. It also ensures there is at least one target node.
• Added debug_mode setting to refactor.context.Configuration
• Added a command-line flag (-d/--enable-debug-mode) to the default CLI runner to change session's configuration.
• When unparsable source code is generated, the contents can be now seen if the debug mode is enabled.
• [Experimental] Added ability to partially recover floating comments (from preceding or succeeding lines) bound to statements.
• The context providers now can be accessed with attribute notation, e.g. self.context.scope instead of self.context.metadata["scope].
• If you access a built-in context provider (scope/ancestry) and it is not already imported, we auto-import it. So most common context providers are now ready to be used.