Tree-Data-Structure/CHANGELOG.md

Changelog

All notable changes to this project are documented here. The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

Unreleased

4.0.0

A breaking release that cleans up the core API and enforces an explicit public surface.

Changed (breaking)

• TreeNode.treeIterator is now a read-only val (set it via the constructor). Use iterator(order) or asSequence(order) to traverse in a different order per call.
• removeChild(child) now only removes a direct child of the receiver (previously it removed the node from its actual parent regardless). Use child.detach() to unhook a node from wherever it lives.
• addChild(child) now throws TreeNodeException if child already has a parent or if the attachment would create a cycle. Call detach() first to move a node.
• clear() no longer detaches the receiver from its own parent; it only removes its descendants.
• path(descendant) now returns List<TreeNode<T>>? (null when descendant is the root or not a descendant) instead of throwing TreeNodeException.

Added

• TreeNode.detach() — removes a node from its parent.
• TreeNode.iterator(order) — a one-shot iterator in a specific order.
• Strict explicitApi() mode across all modules.
• New tree-structure-compose module: a LazyTree composable for Compose Multiplatform.

Migration

• node.treeIterator = PostOrder; for (n in node) { … } → for (n in node.asSequence(PostOrder)) { … }
• root.removeChild(deepNode) → deepNode.detach()
• try { node.path(x) } catch (e: TreeNodeException) { … } → node.path(x)?.let { … }

3.4.0

Added

• Lazy Sequence traversal: asSequence(order), preOrderSequence(), postOrderSequence(), levelOrderSequence() — composes with the Kotlin stdlib and short-circuits.
• Navigation extensions: isLeaf, degree, root(), ancestors(), siblings(), leaves(), descendants().
• Functional extensions: findNode, filterNodes, anyNode, allNodes, countNodes, foldNodes, mapValues, deepCopy, structurallyEquals (all stack-safe).
• New optional modules published as separate artifacts:
  • tree-structure-serialization — kotlinx.serialization support via a TreeNodeDto.
  • tree-structure-coroutines — Flow traversal (asFlow, preOrderFlow, …).
• CHANGELOG.md, expanded README examples, and class-level KDoc (thread-safety / complexity).

Changed

• nodeCount(), height(), clear() and the post-order iterator are now iterative — deep or degenerate (linear) trees no longer throw StackOverflowError.
• Migrated to Kotlin 2.x (K2 compiler) and introduced a Gradle version catalog.
• Build now uses binary-compatibility-validator (committed .api baselines) and Kover.

3.1.5

Fixed

• Removed a stray println in TreeNode.removeChild() that printed to stdout on every removal.

Removed

• Deleted the Example.ws.kts worksheet and the kotlin("script-runtime") dependency from the published JVM artifact, plus the leftover ExampleUnitTest template test.

Changed

• Bumped actions/checkout v2 → v4 in CI workflows.

3.1.4

• Updated Kotlin and JS dependencies; added the wasmJs target.

3.1.3

• iOS targets and Maven Central (Sonatype Central Portal) publishing.