This lists the various API changes that have been made to the RubyTree package.

Note: API changes are expected to reduce significantly after the 1.x release. In most cases, an alternative will be provided to ensure relatively smooth transition to the new APIs.

• The minimum required Ruby version is now 2.6 (or higher).

• The long-broken Tree::TreeNode#depth method has finally been removed. Use Tree::TreeNode#node_depth instead.

• Support for CamelCase methods has been removed. This was a legacy shim that has hopefully outlived its usefulness.

• Use of integers as node-names now no longer requires the optional num_as_name method argument.

• The predicate methods beginning with is_ or has_ are now aliases to the real methods without these prefixes. For example, Tree::TreeNode#is_root? is now aliased to Tree::TreeNode#root?. This is to comply with the Ruby standard. These original prefixed method names should be considered as deprecated and the corresponding non-prefixed method names should be used instead. it is possible that the old prefixed method names might be removed in the future.

• structured_warnings has been removed from the code-base and is no longer a dependency. This was a long-standing point of friction for many users.

• The Tree::TreeNode#add method now provides move semantics, if a child node on an existing tree is added to another tree, or another location on the same tree. In this situation, the child node is removed from its old position and added to the new parent node. After the add operation is complete, the child no longer exists on the old tree/location.

• Validation for unique node names has changed in the Tree::TreeNode#add method. RubyTree no longer enforces globally unique names. The node-names need to be unique only between the sibling nodes.

• New post-ordered traversal via the Tree::TreeNode#postordered_each method.

• The Binary Tree implementation now supports in-order traversal via the Tree::BinaryTreeNode#inordered_each method.

• RubyTree now mixes in the Comparable module.

• The traversal methods (Tree::TreeNode#each, Tree::TreeNode#preordered_each, Tree::TreeNode#postordered_each and Tree::TreeNode#breadth_each now correctly return an Enumerator as the return value when no block is given, and return the receiver node if a block was provided. This is consistent with how the standard Ruby collections work.

• Tree::TreeNode#siblings will now return an empty array for the root node.

• Added the ability to specify an optional insertion position in the Tree::TreeNode#add method. Idea and original code contributed by Dirk.

• Added a new method Tree::TreeNode#detached_subtree_copy to allow cloning the entire tree. This method is also aliased to Tree::TreeNode#dup. Idea and original code contributed by Vincenzo Farruggia.

• Converted all CamelCase method names to the canonical ruby_method_names (underscore separated). The CamelCase methods can still be invoked, but will throw a deprecated warning.

• Converted all exceptions thrown on invalid method arguments to from RuntimeError to ArgumentError. This impacts the following methods:

  • Tree::TreeNode#initialize
  • Tree::TreeNode#add
  • Tree::TreeNode#[]
  • Tree::BinaryTreeNode#add

• Added Tree::TreeNode#level as an alias for Tree::TreeNode#node_depth

• Added new methods Tree::TreeNode#in_degree and Tree::TreeNode#out_degree to report the node's degree stats.

• Tree::TreeNode#is_only_child? now returns true for a root node.

• Tree::TreeNode#next_sibling and Tree::TreeNode#previous_sibling now return nil for a root node.

• Tree::TreeNode#add and Tree::TreeNode#<< now throw an ArgumentError exception if a nil node is passed as an argument.

• Added new methods Tree::TreeNode#to_json and Tree::TreeNode#json_create to convert to/from the JSON format. Thanks to Dirk for this change.

• Deprecated the Tree::Utils::TreeMetricsHandler#depth method as it was returning an incorrect depth value. Have introduced a new replacement method Tree::Utils::TreeMetricsHandler#node_depth which returns the correct result.