Fix property docs not being propagated to generated accessors

dokka-subprojects/plugin-kotlin-as-java/src/main/kotlin/org/jetbrains/dokka/kotlinAsJava/converters/KotlinToJavaConverter.kt

@@ -16,6 +16,9 @@ import org.jetbrains.dokka.plugability.DokkaContext
 import org.jetbrains.dokka.plugability.plugin
 import org.jetbrains.dokka.plugability.querySingle
 import org.jetbrains.dokka.analysis.kotlin.internal.InternalKotlinAnalysisPlugin
+import org.jetbrains.dokka.model.doc.Description
+import org.jetbrains.dokka.model.doc.DocumentationNode
+import org.jetbrains.dokka.model.doc.Property
 
 public val jvmNameProvider: JvmNameProvider = JvmNameProvider()
 internal const val OBJECT_INSTANCE_NAME = "INSTANCE"
@@ -32,6 +35,33 @@ internal val DProperty.isJvmField: Boolean
 internal val DFunction.isJvmStatic: Boolean
     get() = jvmStatic() != null
 
+/**
+ * Converts any `@property` tags into descriptions for the Java accessors
+ */
+private fun transformAccessorDocs(docs: SourceSetDependent<DocumentationNode>): SourceSetDependent<DocumentationNode> {
+    return docs.mapValues { (_, node) ->
+        node.copy(
+            children = node.children.map { tag ->
+                if (tag is Property) {
+                    Description(tag.root)
+                } else {
+                    tag
+                }
+            }
+        )
+    }
+}
+
+internal val DProperty.documentedGetter: DFunction?
+    get() = getter?.copy(
+        documentation = transformAccessorDocs(getter?.documentation?.takeIf { it.isNotEmpty() } ?: documentation)
+    )
+
+internal val DProperty.documentedSetter: DFunction?
+    get() = setter?.copy(
+        documentation = transformAccessorDocs(setter?.documentation?.takeIf { it.isNotEmpty() } ?: documentation)
+    )
+
 private fun DProperty.hasModifier(modifier: ExtraModifiers.KotlinOnlyModifiers): Boolean =
     extra[AdditionalModifiers]
         ?.content
@@ -306,7 +336,7 @@ public class KotlinToJavaConverter(
     internal fun DClass.functionsInJava(): List<DFunction> =
         properties
             .filter { !it.isJvmField && !it.hasJvmSynthetic() }
-            .flatMap { property -> listOfNotNull(property.getter, property.setter) }
+            .flatMap { property -> listOfNotNull(property.documentedGetter, property.documentedSetter) }
             .plus(functions)
             .plus(companion.staticFunctionsForJava())
             .filterNot { it.hasJvmSynthetic() }
@@ -370,7 +400,7 @@ public class KotlinToJavaConverter(
             .plus(
                 properties
                     .filter { !it.isJvmField && !it.hasJvmSynthetic() }
-                    .flatMap { listOf(it.getter, it.setter) }
+                    .flatMap { listOf(it.documentedGetter, it.documentedSetter) }
             )
             .filterNotNull()
             .filterNot { it.hasJvmSynthetic() }
@@ -396,7 +426,7 @@ public class KotlinToJavaConverter(
                 properties
                     .filterNot { it in excludedProps }
                     .filter { !it.isJvmField && !it.isConst && !it.isLateInit && !it.hasJvmSynthetic() }
-                    .flatMap { listOf(it.getter, it.setter) }
+                    .flatMap { listOf(it.documentedGetter, it.documentedSetter) }
             )
             .filterNotNull()
             .filterNot { it in excludedFunctions }
@@ -436,7 +466,7 @@ public class KotlinToJavaConverter(
             .plus(
                 properties
                     .filter { it.jvmField() == null && !it.hasJvmSynthetic() }
-                    .flatMap { listOf(it.getter, it.setter) }
+                    .flatMap { listOf(it.documentedGetter, it.documentedSetter) }
             )
             .filterNotNull()
             .filterNot { it.hasJvmSynthetic() }

dokka-subprojects/plugin-kotlin-as-java/src/test/kotlin/kotlinAsJavaPlugin/PropertyTest.kt

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2014-2024 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinAsJavaPlugin
+
+import org.jetbrains.dokka.base.testApi.testRunner.BaseAbstractTest
+import org.jetbrains.dokka.model.Documentable
+import org.jetbrains.dokka.model.doc.DocTag
+import org.jetbrains.dokka.model.doc.Text
+import kotlin.test.*
+
+class PropertyTest : BaseAbstractTest() {
+    val configuration = dokkaConfiguration {
+        sourceSets {
+            sourceSet {
+                sourceRoots = listOf("src/")
+                classpath += jvmStdlibPath!!
+            }
+        }
+    }
+
+    @Test
+    fun `property accessors should inherit doc`(){
+        testInline(
+            """
+            |/src/main/kotlin/kotlinAsJavaPlugin/sample.kt
+            |package kotlinAsJavaPlugin
+            |class MyClass {
+            |    /**
+            |    * Some doc
+            |    */
+            |    var property: String = TODO()
+            |}
+        """.trimMargin(),
+            configuration,
+        ) {
+            documentablesTransformationStage = { module ->
+                val classLike = module.packages.flatMap { it.classlikes }.first()
+                val getter = classLike.functions.firstOrNull { it.name == "getProperty" }
+                val setter = classLike.functions.firstOrNull { it.name == "setProperty" }
+                assertNotNull(getter)
+                assertNotNull(setter)
+
+                assertEquals("Some doc", getter.docText)
+                assertEquals("Some doc", setter.docText)
+            }
+        }
+
+        testInline(
+            """
+            |/src/main/kotlin/kotlinAsJavaPlugin/sample.kt
+            |package kotlinAsJavaPlugin
+            |/**
+            |* @property property Some doc
+            |*/
+            |class MyClass {
+            |    var property: String = TODO()
+            |}
+        """.trimMargin(),
+            configuration,
+        ) {
+            documentablesTransformationStage = { module ->
+                val classLike = module.packages.flatMap { it.classlikes }.first()
+                val getter = classLike.functions.firstOrNull { it.name == "getProperty" }
+                val setter = classLike.functions.firstOrNull { it.name == "setProperty" }
+                assertNotNull(getter)
+                assertNotNull(setter)
+
+                assertEquals("Some doc", getter.docText)
+                assertEquals("Some doc", setter.docText)
+            }
+        }
+    }
+}
+
+private val Documentable.docText: String
+    get() = this.documentation.values
+        .flatMap { it.children }
+        .map { it.root }
+        .joinToString("") { it.text }
+
+private val DocTag.text: String
+    get() = if (this is Text) body else children.joinToString("") { it.text }