Bump version to 3.1.2

* Refactor: Modernize build and publishing workflow

- Upgraded Kotlin from 1.7.20 to 1.9.20.
- Upgraded JDK from 11 to 21 across all GitHub Actions workflows.
- Replaced the legacy `maven-publish` plugin with `com.vanniktech.maven.publish` for simplified publishing to Maven Central.
- Removed the `publishSnapshot.yml` workflow, as snapshot publishing is now managed by the new plugin.
- Updated `publishRelease.yml` to use the `publishToMavenCentral` task and new secrets (`MAVEN_CENTRAL_USERNAME`, `MAVEN_CENTRAL_PASSWORD`).
- Simplified `build.gradle.kts` by removing manual publishing and signing logic.
- Set the JVM target to "21".
- Bumped the project version to `3.1.1`.
- Removed `js` targets and related configurations.
- Added a new code style configuration file for the project (`.idea/codeStyles/Project.xml`).

* fix: Add JavaScript targets

- Added JS (IR) targets (`browser` and `nodejs`) to the Kotlin Multiplatform configuration for publishing.

* Improve README and document new publishing workflow

- Expanded the project description to highlight key features like Kotlin Multiplatform support, traversal iterators, DSL, and utility functions.
- Added a new "Installation" section with instructions for Gradle (Kotlin/Groovy) and Maven.
- Added a "Traversal and utilities" section to demonstrate usage of iterators and helper functions.
- Replaced the old publishing documentation with updated instructions for publishing to Maven Central via the Central Portal.
- Detailed the two publishing methods: automatically via GitHub Actions on release and manually via local Gradle commands.
- Clarified required secrets and environment variables for the new publishing process.

.github/dependabot.yml

@@ -0,0 +1,11 @@
+# To get started with Dependabot version updates, you'll need to specify which
+# package ecosystems to update and where the package manifests are located.
+# Please see the documentation for all configuration options:
+# https://docs.github.com/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file
+
+version: 2
+updates:
+  - package-ecosystem: "" # See documentation for possible values
+    directory: "/" # Location of package manifests
+    schedule:
+      interval: "weekly"

.github/workflows/publishRelease.yml

@@ -19,20 +19,18 @@ jobs:
     steps:
       - name: Check out code
         uses: actions/checkout@v2
-      - name: Set up JDK 11
+      - name: Set up JDK 21
-        uses: actions/setup-java@v2
+        uses: actions/setup-java@v4
         with:
-          distribution: adopt
+          distribution: temurin
-          java-version: 11
+          java-version: '21'
 
         # Runs upload, and then closes & releases the repository
       - name: Publish to MavenCentral
-        run: ./gradlew publish --max-workers 1
+        run: ./gradlew publishToMavenCentral
         env:
-          OSSRH_USERNAME: ${{ secrets.OSSRH_USERNAME }}
+          ORG_GRADLE_PROJECT_mavenCentralUsername: ${{ secrets.MAVEN_CENTRAL_USERNAME }}
-          OSSRH_PASSWORD: ${{ secrets.OSSRH_PASSWORD }}
+          ORG_GRADLE_PROJECT_mavenCentralPassword: ${{ secrets.MAVEN_CENTRAL_PASSWORD }}
-          SIGNING_KEY_ID: ${{ secrets.SIGNING_KEY_ID }}
+          ORG_GRADLE_PROJECT_signingInMemoryKey: ${{ secrets.SIGNING_KEY }}
-          SIGNING_PASSWORD: ${{ secrets.SIGNING_PASSWORD }}
+          ORG_GRADLE_PROJECT_signingInMemoryKeyPassword: ${{ secrets.SIGNING_PASSWORD }}
-          SIGNING_KEY: ${{ secrets.SIGNING_KEY }}
-          SONATYPE_STAGING_PROFILE_ID: ${{ secrets.SONATYPE_STAGING_PROFILE_ID }}
           SNAPSHOT: false

.github/workflows/publishSnapshot.yml

@@ -1,35 +0,0 @@
-name: Publish Snapshot
-
-on:
-  push:
-    branches: [master, '14-**']
-
-jobs:
-  test:
-    uses: ./.github/workflows/test.yml
-    secrets: inherit
-
-  publish:
-    needs: test
-    name: Publish Snapshot
-    runs-on: ubuntu-latest
-    steps:
-      - name: Check out code
-        uses: actions/checkout@v2
-      - name: Set up JDK 11
-        uses: actions/setup-java@v2
-        with:
-          distribution: adopt
-          java-version: 11
-
-        # Runs upload, and then closes & releases the repository
-      - name: Publish to snapshot to Sonatype
-        run: ./gradlew publish --max-workers 1
-        env:
-          OSSRH_USERNAME: ${{ secrets.OSSRH_USERNAME }}
-          OSSRH_PASSWORD: ${{ secrets.OSSRH_PASSWORD }}
-          SIGNING_KEY_ID: ${{ secrets.SIGNING_KEY_ID }}
-          SIGNING_PASSWORD: ${{ secrets.SIGNING_PASSWORD }}
-          SIGNING_KEY: ${{ secrets.SIGNING_KEY }}
-          SONATYPE_STAGING_PROFILE_ID: ${{ secrets.SONATYPE_STAGING_PROFILE_ID }}
-          SNAPSHOT: true

.github/workflows/test.yml

@@ -12,12 +12,12 @@ jobs:
     steps:
       - name: Check out code
         uses: actions/checkout@v2
-      - name: Set up JDK 11
+      - name: Set up JDK 21
-        uses: actions/setup-java@v2
+        uses: actions/setup-java@v4
         with:
-          distribution: adopt
+          distribution: temurin
-          java-version: 11
+          java-version: '21'
 
         # Builds the release artifacts of the library
       - name: Test
-        run: ./gradlew test
+        run: ./gradlew cleanJvmTest jvmTest

.idea/AndroidProjectSystem.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="AndroidProjectSystem">
+    <option name="providerId" value="com.android.tools.idea.GradleProjectSystem" />
+  </component>
+</project>

.idea/codeStyles/Project.xml

@@ -1,5 +1,40 @@
 <component name="ProjectCodeStyleConfiguration">
   <code_scheme name="Project" version="173">
+    <JavaCodeStyleSettings>
+      <option name="IMPORT_LAYOUT_TABLE">
+        <value>
+          <package name="" withSubpackages="true" static="false" module="true" />
+          <package name="android" withSubpackages="true" static="true" />
+          <package name="androidx" withSubpackages="true" static="true" />
+          <package name="com" withSubpackages="true" static="true" />
+          <package name="junit" withSubpackages="true" static="true" />
+          <package name="net" withSubpackages="true" static="true" />
+          <package name="org" withSubpackages="true" static="true" />
+          <package name="java" withSubpackages="true" static="true" />
+          <package name="javax" withSubpackages="true" static="true" />
+          <package name="" withSubpackages="true" static="true" />
+          <emptyLine />
+          <package name="android" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="androidx" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="com" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="junit" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="net" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="org" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="java" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="javax" withSubpackages="true" static="false" />
+          <emptyLine />
+          <package name="" withSubpackages="true" static="false" />
+          <emptyLine />
+        </value>
+      </option>
+    </JavaCodeStyleSettings>
     <JetCodeStyleSettings>
       <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
     </JetCodeStyleSettings>

.idea/gradle.xml

@@ -4,8 +4,9 @@
   <component name="GradleSettings">
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>
-        <option name="distributionType" value="WRAPPED" />
+        <option name="testRunner" value="CHOOSE_PER_TEST" />
         <option name="externalProjectPath" value="$PROJECT_DIR$" />
+        <option name="gradleJvm" value="#GRADLE_LOCAL_JAVA_HOME" />
         <option name="modules">
           <set>
             <option value="$PROJECT_DIR$" />

.idea/kotlinScripting.xml

@@ -1,9 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="KotlinScriptingSettings">
-    <scriptDefinition className="org.jetbrains.kotlin.scripting.resolve.KotlinScriptDefinitionFromAnnotatedTemplate" definitionName="KotlinBuildScript">
-      <order>2147483647</order>
-      <autoReloadConfigurations>true</autoReloadConfigurations>
-    </scriptDefinition>
-  </component>
-</project>

.idea/misc.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ExternalStorageConfigurationManager" enabled="true" />
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" default="true" project-jdk-name="11" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_21" default="true" project-jdk-name="jbr-21" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>

.idea/runConfigurations.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="RunConfigurationProducerService">
+    <option name="ignoredProducers">
+      <set>
+        <option value="com.intellij.execution.junit.AbstractAllInDirectoryConfigurationProducer" />
+        <option value="com.intellij.execution.junit.AllInPackageConfigurationProducer" />
+        <option value="com.intellij.execution.junit.PatternConfigurationProducer" />
+        <option value="com.intellij.execution.junit.TestInClassConfigurationProducer" />
+        <option value="com.intellij.execution.junit.UniqueIdConfigurationProducer" />
+        <option value="com.intellij.execution.junit.testDiscovery.JUnitTestDiscoveryConfigurationProducer" />
+        <option value="org.jetbrains.kotlin.idea.junit.KotlinJUnitRunConfigurationProducer" />
+        <option value="org.jetbrains.kotlin.idea.junit.KotlinPatternConfigurationProducer" />
+      </set>
+    </option>
+  </component>
+</project>

.idea/studiobot.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="StudioBotProjectSettings">
+    <option name="shareContext" value="OptedIn" />
+  </component>
+</project>

.idea/vcs.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+    <mapping directory="" vcs="Git" />
   </component>
 </project>

README.md

@@ -1,9 +1,40 @@
 # Tree (Data Structure)
 [![maven](https://img.shields.io/maven-central/v/com.github.adriankuta/tree-structure?style=plastic)](https://mvnrepository.com/artifact/com.github.adriankuta/tree-structure)
 [![License: MIT](https://img.shields.io/github/license/AdrianKuta/Tree-Data-Structure?style=plastic)](https://github.com/AdrianKuta/Tree-Data-Structure/blob/master/LICENSE)
-[![Publish](https://github.com/AdrianKuta/Tree-Data-Structure/actions/workflows/publishRelease.yml/badge.svg)](https://github.com/AdrianKuta/Tree-Data-Structure/actions/workflows/publish.yml)
+[![Publish](https://github.com/AdrianKuta/Tree-Data-Structure/actions/workflows/publishRelease.yml/badge.svg)](https://github.com/AdrianKuta/Tree-Data-Structure/actions/workflows/publishRelease.yml)
 
-Simple implementation to store object in tree structure.
+Lightweight Kotlin Multiplatform tree data structure for Kotlin and Java. Includes a small DSL, multiple traversal iterators, and pretty-print support.
+
+- Kotlin Multiplatform (JVM, JS, iOS, and Native host)
+- Pre-order, Post-order, and Level-order iteration
+- Simple DSL: tree { child(...) }
+- Utilities: nodeCount(), height(), depth(), path(), prettyString(), clear(), removeChild()
+
+## Installation
+
+Gradle (Kotlin DSL):
+```kotlin
+// commonMain for KMP projects, or any sourceSet/module where you need it
+dependencies {
+    implementation("com.github.adriankuta:tree-structure:3.1.1") // see badge above for the latest version
+}
+```
+
+Gradle (Groovy):
+```groovy
+dependencies {
+    implementation "com.github.adriankuta:tree-structure:3.1.1" // see badge above for the latest
+}
+```
+
+Maven:
+```xml
+<dependency>
+  <groupId>com.github.adriankuta</groupId>
+  <artifactId>tree-structure</artifactId>
+  <version>3.1.1</version>
+</dependency>
+```
 
 ## Usage
 
@@ -25,19 +56,15 @@ europe.addChild(france)
 println(root.prettyString())
 ```
 
-**Pretty Kotlin**
+**Pretty Kotlin (DSL)**
-
 ```kotlin
-val root =
+val root = tree("World") {
-    tree("World") {
+    child("North America") { child("USA") }
-        child("North America") {
-            child("USA")
-        }
     child("Europe") {
         child("Poland")
         child("Germany")
     }
-    }
+}
 ```
 
 **Java**
@@ -58,8 +85,7 @@ europe.addChild(france);
 System.out.println(root.prettyString());
 ```
 
-*Output:*
+Output:
-
 ```
 World
 ├── North America
@@ -69,10 +95,58 @@ World
     └── France
 ```
 
+### Traversal and utilities
+```kotlin
+val root = TreeNode("root")
+// ... build your tree
 
-## Download
+// Choose iteration order (default is PreOrder)
+root.treeIterator = TreeNodeIterators.PostOrder
+for (node in root) println(node.value)
 
-    implementation "com.github.adriankuta:tree-structure:$latest_versions"
+// Utilities
+root.nodeCount()   // number of descendants
+root.height()      // longest path to a leaf (in edges)
+root.depth()       // distance from current node to the root
+val path = root.path(root.children.first()) // nodes from descendant up to root
+
+// Mutations
+val child = root.children.first()
+root.removeChild(child)
+root.clear()       // remove entire subtree
+```
+
+## Publishing to Maven Central (central.sonatype.com)
+
+This project is configured to publish artifacts to Maven Central via the Sonatype Central Portal.
+
+There are two supported ways to publish:
+
+1) Via GitHub Actions (recommended)
+- Create a GitHub Release (tag) in this repository. When a release is published, the workflow .github/workflows/publishRelease.yml runs automatically.
+- The workflow uses the Gradle task publishToMavenCentral to upload artifacts through the Central Portal.
+- Make sure these repository secrets are configured in GitHub:
+  - MAVEN_CENTRAL_USERNAME — Your Sonatype Central username (not email).
+  - MAVEN_CENTRAL_PASSWORD — Your Sonatype Central password or a token from central.sonatype.com.
+  - SIGNING_KEY — ASCII‑armored GPG private key (exported, single line; for in‑memory signing).
+  - SIGNING_PASSWORD — Passphrase for the key above.
+- The workflow uses JDK 21 and publishes the version defined in build.gradle.kts.
+
+2) Locally via Gradle
+- Ensure you have a Sonatype Central account and that the groupId com.github.adriankuta is verified in central.sonatype.com (Namespace Rules → Verify).
+- Export the same credentials/signing values as environment variables or pass them as Gradle properties:
+  - ORG_GRADLE_PROJECT_mavenCentralUsername
+  - ORG_GRADLE_PROJECT_mavenCentralPassword
+  - ORG_GRADLE_PROJECT_signingInMemoryKey
+  - ORG_GRADLE_PROJECT_signingInMemoryKeyPassword
+- Then run:
+  - ./gradlew publishToMavenCentral
+- For snapshot publishing, set -Psnapshot=true (the version is derived from PUBLISH_VERSION with -SNAPSHOT).
+
+Notes
+- Publishing is powered by the com.vanniktech.maven.publish Gradle plugin and Sonatype Central Portal (no legacy Nexus staging URLs needed).
+- The plugin is configured to sign all publications. Coordinates and POM metadata are defined in build.gradle.kts.
+- If using the combined task is preferred, you can also run publishAndReleaseToMavenCentral when automatic release is enabled; this repository currently uploads with publishToMavenCentral from CI.
 
 ## License
 
@@ -97,3 +171,5 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
+
+---

build.gradle.kts

@@ -1,123 +1,88 @@
 import org.jetbrains.kotlin.konan.properties.Properties
 
 plugins {
-    kotlin("multiplatform") version "1.7.20"
+    kotlin("multiplatform") version "1.9.20"
-    id("org.jetbrains.dokka") version "1.7.20"
+    id("org.jetbrains.dokka") version "1.9.20"
-    id("maven-publish")
+    id("com.vanniktech.maven.publish") version "0.34.0"
     signing
 }
 
 val PUBLISH_GROUP_ID = "com.github.adriankuta"
-val PUBLISH_ARTIFACT_ID = "tree-structure"
+val PUBLISH_ARTIFACT_ID = "tree-structure"    // base artifact; KMP will add -jvm, -ios*, etc.
-val PUBLISH_VERSION = "3.0.1"
+val PUBLISH_VERSION = "3.1.2"
 
-val secretFile = File(rootProject.rootDir, "local.properties")
-if (secretFile.exists()) {
-    secretFile.reader().use {
-        Properties().apply {
-            load(it)
-        }
-    }.onEach { (name, value) ->
-        project.ext[name.toString()] = value
-    }
-} else {
-    project.ext["ossrhUsername"] = System.getenv("OSSRH_USERNAME")
-    project.ext["ossrhPassword"] = System.getenv("OSSRH_PASSWORD")
-    project.ext["sonatypeStagingProfileId"] = System.getenv("SONATYPE_STAGING_PROFILE_ID")
-    project.ext["signingKeyId"] = System.getenv("SIGNING_KEY_ID")
-    project.ext["signingPassword"] = System.getenv("SIGNING_PASSWORD")
-    project.ext["signingKey"] = System.getenv("SIGNING_KEY")
-    project.ext["snapshot"] = System.getenv("SNAPSHOT")
-}
 val snapshot: String? by project
 
 group = PUBLISH_GROUP_ID
 version = if (snapshot.toBoolean()) "$PUBLISH_VERSION-SNAPSHOT" else PUBLISH_VERSION
 
-val dokkaHtml by tasks.getting(org.jetbrains.dokka.gradle.DokkaTask::class)
+mavenPublishing {
+    // Central Portal + auto release when we call publishAndReleaseToMavenCentral
+    publishToMavenCentral(automaticRelease = false)
+    signAllPublications()
 
-val javadocJar: TaskProvider<Jar> by tasks.registering(Jar::class) {
+    coordinates(PUBLISH_GROUP_ID, PUBLISH_ARTIFACT_ID, version.toString())
-    dependsOn(dokkaHtml)
-    archiveClassifier.set("javadoc")
-    from(dokkaHtml.outputDirectory)
-}
 
-publishing {
-    publications {
-
-        withType<MavenPublication> {
-            artifact(javadocJar)
     pom {
         name.set("Tree Data Structure")
         description.set("Simple implementation to store object in tree structure.")
         url.set("https://github.com/AdrianKuta/Tree-Data-Structure")
+
         licenses {
             license {
                 name.set("MIT License")
-                        url.set("https://www.mit.edu/~amini/LICENSE.md")
+                url.set("https://opensource.org/licenses/MIT")
+                distribution.set("repo")
             }
         }
         developers {
             developer {
+                id.set("AdrianKuta")
                 name.set("Adrian Kuta")
                 email.set("adrian.kuta93@gmail.com")
             }
         }
         scm {
-                    connection.set("scm:git:github.com/AdrianKuta/Tree-Data-Structure.git")
+            url.set("https://github.com/AdrianKuta/Tree-Data-Structure")
-                    developerConnection.set("scm:git:ssh://github.com/AdrianKuta/Tree-Data-Structure.git")
+            connection.set("scm:git:https://github.com/AdrianKuta/Tree-Data-Structure.git")
-                    url.set("https://github.com/AdrianKuta/Tree-Data-Structure/tree/master")
+            developerConnection.set("scm:git:ssh://git@github.com/AdrianKuta/Tree-Data-Structure.git")
-                }
-            }
-        }
-    }
-
-    repositories {
-        maven {
-            name = "Sonatype"
-            val releasesRepoUrl = "https://oss.sonatype.org/service/local/staging/deploy/maven2"
-            val snapshotsRepoUrl = "https://oss.sonatype.org/content/repositories/snapshots"
-            url = uri(if (version.toString().endsWith("SNAPSHOT")) snapshotsRepoUrl else releasesRepoUrl)
-            credentials {
-                val ossrhUsername: String? by project
-                val ossrhPassword: String? by project
-                username = ossrhUsername
-                password = ossrhPassword
-            }
         }
     }
 }
 
-signing {
+// No legacy publishing {} block or s01 repos — Central Portal handles it.
-    val signingKeyId: String? by project
-    val signingPassword: String? by project
-    val signingKey: String? by project
-    useInMemoryPgpKeys(signingKeyId, signingKey, signingPassword)
-
-    sign(publishing.publications)
-}
 
 repositories {
     mavenCentral()
 }
 
+java {
+    toolchain {
+        languageVersion.set(JavaLanguageVersion.of(21))
+    }
+}
 kotlin {
+    jvmToolchain(21);
     jvm {
         compilations.all {
-            kotlinOptions.jvmTarget = "1.8"
+            kotlinOptions {
-        }
+                jvmTarget = "21"   // <- was "1.8"
-        withJava()
-        testRuns["test"].executionTask.configure {
-            useJUnitPlatform()
-        }
-    }
-    js(BOTH) {
-        browser {
-            commonWebpackConfig {
-                cssSupport.enabled = true
             }
         }
     }
+
+    // JS targets (IR) for publishing
+    js(IR) {
+        browser()
+        nodejs()
+    }
+
+    // iOS targets
+    iosX64()
+    iosArm64()
+    iosSimulatorArm64()
+
+    // Native host target
     val hostOs = System.getProperty("os.name")
     val isMingwX64 = hostOs.startsWith("Windows")
     val nativeTarget = when {
@@ -127,23 +92,24 @@ kotlin {
         else -> throw GradleException("Host OS is not supported in Kotlin/Native.")
     }
 
-
     sourceSets {
         val commonMain by getting
-        val commonTest by getting {
+        val commonTest by getting { dependencies { implementation(kotlin("test")) } }
-            dependencies {
+        val jvmMain by getting { dependencies { implementation(kotlin("script-runtime")) } }
-                implementation(kotlin("test"))
-            }
-        }
-        val jvmMain by getting {
-            dependencies {
-                implementation(kotlin("script-runtime"))
-            }
-        }
         val jvmTest by getting
         val jsMain by getting
         val jsTest by getting
         val nativeMain by getting
         val nativeTest by getting
+
+        // Shared iOS source sets
+        val iosMain by creating { dependsOn(commonMain) }
+        val iosTest by creating { dependsOn(commonTest) }
+        val iosX64Main by getting { dependsOn(iosMain) }
+        val iosArm64Main by getting { dependsOn(iosMain) }
+        val iosSimulatorArm64Main by getting { dependsOn(iosMain) }
+        val iosX64Test by getting { dependsOn(iosTest) }
+        val iosArm64Test by getting { dependsOn(iosTest) }
+        val iosSimulatorArm64Test by getting { dependsOn(iosTest) }
     }
 }

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,7 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.4.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.5-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

gradlew

@@ -55,7 +55,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.
@@ -80,13 +80,11 @@ do
     esac
 done
 
-APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+# This is normally unused
-
+# shellcheck disable=SC2034
-APP_NAME="Gradle"
 APP_BASE_NAME=${0##*/}
-
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
-# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+APP_HOME=$( cd "${APP_HOME:-./}" > /dev/null && pwd -P ) || exit
-DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
@@ -133,22 +131,29 @@ location of your Java installation."
     fi
 else
     JAVACMD=java
-    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
 
 Please set the JAVA_HOME variable in your environment to match the
 location of your Java installation."
+    fi
 fi
 
 # Increase the maximum file descriptors if we can.
 if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
     case $MAX_FD in #(
       max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
         MAX_FD=$( ulimit -H -n ) ||
             warn "Could not query maximum file descriptor limit"
     esac
     case $MAX_FD in  #(
       '' | soft) :;; #(
       *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
         ulimit -n "$MAX_FD" ||
             warn "Could not set maximum file descriptor limit to $MAX_FD"
     esac
@@ -193,11 +198,15 @@ if "$cygwin" || "$msys" ; then
     done
 fi
 
-# Collect all arguments for the java command;
+
-#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-#     shell script including quotes and variable substitutions, so put them in
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
-#     double quotes to make sure that they get re-expanded; and
+
-#   * put everything else in single quotes, so that it's not re-expanded.
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
@@ -205,6 +214,12 @@ set -- \
         org.gradle.wrapper.GradleWrapperMain \
         "$@"
 
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
 # Use "xargs" to parse quoted args.
 #
 # With -n1 it outputs one arg per line, with the quotes and backslashes removed.

gradlew.bat

@@ -14,7 +14,7 @@
 @rem limitations under the License.
 @rem
 
-@if "%DEBUG%" == "" @echo off
+@if "%DEBUG%"=="" @echo off
 @rem ##########################################################################
 @rem
 @rem  Gradle startup script for Windows
@@ -25,7 +25,8 @@
 if "%OS%"=="Windows_NT" setlocal
 
 set DIRNAME=%~dp0
-if "%DIRNAME%" == "" set DIRNAME=.
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
 set APP_BASE_NAME=%~n0
 set APP_HOME=%DIRNAME%
 
@@ -40,7 +41,7 @@ if defined JAVA_HOME goto findJavaFromJavaHome
 
 set JAVA_EXE=java.exe
 %JAVA_EXE% -version >NUL 2>&1
-if "%ERRORLEVEL%" == "0" goto execute
+if %ERRORLEVEL% equ 0 goto execute
 
 echo.
 echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
@@ -75,13 +76,15 @@ set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
 
 :end
 @rem End local scope for the variables with windows NT shell
-if "%ERRORLEVEL%"=="0" goto mainEnd
+if %ERRORLEVEL% equ 0 goto mainEnd
 
 :fail
 rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
 rem the _cmd.exe /c_ return code!
-if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+set EXIT_CODE=%ERRORLEVEL%
-exit /b 1
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
 
 :mainEnd
 if "%OS%"=="Windows_NT" endlocal

src/commonMain/kotlin/com.github.adriankuta/datastructure/tree/TreeNode.kt

@@ -8,7 +8,10 @@ import com.github.adriankuta.datastructure.tree.iterators.TreeNodeIterators
 import com.github.adriankuta.datastructure.tree.iterators.TreeNodeIterators.*
 import kotlin.jvm.JvmSynthetic
 
-open class TreeNode<T>(val value: T) : Iterable<TreeNode<T>>, ChildDeclarationInterface<T> {
+/**
+ * @param treeIterator Choose one of available iterators from [TreeNodeIterators]
+ */
+open class TreeNode<T>(val value: T, var treeIterator: TreeNodeIterators = PreOrder) : Iterable<TreeNode<T>>, ChildDeclarationInterface<T> {
 
     private var _parent: TreeNode<T>? = null
 
@@ -33,11 +36,6 @@ open class TreeNode<T>(val value: T) : Iterable<TreeNode<T>>, ChildDeclarationIn
     val isRoot: Boolean
         get() = _parent == null
 
-    /**
-     * Choose one of available iterators from [TreeNodeIterators]
-     */
-    var defaultIterator: TreeNodeIterators = PreOrder
-
     /**
      * Add new child to current node or root.
      *
@@ -166,9 +164,9 @@ open class TreeNode<T>(val value: T) : Iterable<TreeNode<T>>, ChildDeclarationIn
     }
 
     /**
-     * You can change default iterator by changing [defaultIterator] property.
+     * You can change default iterator by changing [treeIterator] property.
      */
-    override fun iterator(): Iterator<TreeNode<T>> = when (defaultIterator) {
+    override fun iterator(): Iterator<TreeNode<T>> = when (treeIterator) {
         PreOrder -> PreOrderTreeIterator(this)
         PostOrder -> PostOrderTreeIterator(this)
         LevelOrder -> LevelOrderTreeIterator(this)

src/commonMain/kotlin/com.github.adriankuta/datastructure/tree/TreeNodeExt.kt

@@ -19,8 +19,7 @@ inline fun <reified T> tree(
     defaultIterator: TreeNodeIterators = TreeNodeIterators.PreOrder,
     childDeclaration: ChildDeclaration<T>
 ): TreeNode<T> {
-    val treeNode = TreeNode(root)
+    val treeNode = TreeNode(root, defaultIterator)
-    treeNode.defaultIterator = defaultIterator
     treeNode.childDeclaration()
     return treeNode
 }