Documentation generation (Dokka HTML) (#3)

Generate documentation HTML and `javadoc.jar`.

Reviewed-on: #3

build.gradle.kts

@@ -1,6 +1,7 @@
 plugins {
     kotlin("jvm") version "1.9.21"
     id("org.jmailen.kotlinter") version "4.1.0"
+    id("org.jetbrains.dokka") version "1.9.10"
     `maven-publish`
 }
 
@@ -23,10 +24,18 @@ kotlin {
     jvmToolchain(17)
 }
 
+val dokkaHtml by tasks.getting(org.jetbrains.dokka.gradle.DokkaTask::class)
+val javadocJar: TaskProvider<Jar> by tasks.registering(Jar::class) {
+    dependsOn(dokkaHtml)
+    archiveClassifier.set("javadoc")
+    from(dokkaHtml.outputDirectory)
+}
+
 publishing {
     publications.register<MavenPublication>("gpr") {
         artifactId = "tinyvm"
         from(components["java"])
+        artifact(javadocJar)
         pom {
             name.set("TeamCity support for Gitea - Test Task - tiny version manager")
             description.set("This is a small project to implement a subset of git's functionality in Kotlin and was " +

src/main/kotlin/tinyvm/Commit.kt

@@ -2,28 +2,36 @@ package tinyvm
 
 import java.security.MessageDigest
 import java.time.Instant
+import java.util.HexFormat
 
-abstract class Object(
+/**
-    val type: String,
+ * Represents an arbitrary version manager object.
-) {
+ */
+abstract class Object(val type: String) {
     abstract val data: String
 
     fun hash(): String =
-        MessageDigest
+        HexFormat.of().formatHex(
-            .getInstance("SHA-1")
+            MessageDigest
-            .digest("$type ${data.length}\u0000$data".toByteArray())
+                .getInstance("SHA-1")
-            .toHex()
+                .digest("$type ${data.length}\u0000$data".toByteArray()),
+        )
 }
 
+/**
+ * Commits are a pointer to a 'head' tree with some metadata.
+ */
 class Commit(
     val tree: Tree,
     val author: Author,
     val message: String,
     val timestamp: Instant,
 ) : Object("commit") {
-    // Use \n\n for end of header in-case additional metadata is implemented in the future.
     override val data: String
+        // Use \n\n for end of header in-case additional metadata is implemented in the future.
         get() = "tree ${tree.hash()}\nauthor $author\ntimestamp ${timestamp.epochSecond}\n\n$message"
+
+    override fun toString(): String = "commit ${hash()}\n$data"
 }
 
 data class Author(

src/main/kotlin/tinyvm/Extensions.kt

@@ -1,5 +0,0 @@
-package tinyvm
-
-import java.util.HexFormat
-
-fun ByteArray.toHex(): String = HexFormat.of().formatHex(this)

src/main/kotlin/tinyvm/Tree.kt

@@ -1,7 +1,13 @@
 package tinyvm
 
+/**
+ * Tree nodes are either trees or blobs, represented by this sealed class.
+ */
 sealed class Node(type: String) : Object(type)
 
+/**
+ * A tree is a set of named nodes.
+ */
 class Tree(val nodes: Map<String, Node>) : Node("tree") {
     // For simplicity just use the hex-formatted hash, not the actual value like git does.
     override val data: String
@@ -11,4 +17,7 @@ class Tree(val nodes: Map<String, Node>) : Node("tree") {
             }.sorted().joinToString()
 }
 
+/**
+ * A blob is a data container.
+ */
 class Blob(override val data: String) : Node("blob")