Fix suppressGeneratedFiles was unused

Author: whyoleg

dokka-runners/dokka-gradle-plugin/src/main/kotlin/DokkaBasePlugin.kt

@@ -202,6 +202,15 @@ constructor(
             sourceSetScope.convention(sourceSetScopeConvention)
 
             suppressGeneratedFiles.convention(true)
+            suppressedFiles.from(
+                suppressGeneratedFiles.map { suppressGenerated ->
+                    if (suppressGenerated) {
+                        layout.buildDirectory.dir("generated")
+                    } else {
+                        objects.fileCollection()
+                    }
+                }
+            )
 
             sourceLinks.configureEach {
                 localDirectory.convention(layout.projectDirectory)

dokka-runners/dokka-gradle-plugin/src/testFunctional/kotlin/SuppressGeneratedFilesFunctionalTest.kt

@@ -0,0 +1,131 @@
+/*
+ * Copyright 2014-2024 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+package org.jetbrains.dokka.gradle
+
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.paths.shouldExist
+import io.kotest.matchers.string.shouldContain
+import io.kotest.matchers.string.shouldNotContain
+import org.jetbrains.dokka.gradle.internal.DokkaConstants.DOKKA_VERSION
+import org.jetbrains.dokka.gradle.utils.*
+import java.nio.file.Path
+import kotlin.io.path.readText
+
+class SuppressGeneratedFilesFunctionalTest : FunSpec({
+
+    context("suppressGeneratedFiles") {
+
+        test("when suppressGeneratedFiles is true, generated files should be suppressed") {
+            val project = createProject(suppressGeneratedFiles = true)
+
+            project.runner
+                .addArguments(
+                    ":dokkaGeneratePublicationHtml",
+                    "--rerun-tasks",
+                    "--stacktrace",
+                )
+                .build {
+                    val htmlContent = project.projectDir
+                        .resolve("build/dokka/html/suppress-generated-files-true/[root]/index.html")
+                        .also(Path::shouldExist)
+                        .readText()
+                    htmlContent shouldContain "MyClass"
+                    htmlContent shouldNotContain "GeneratedClass"
+                    htmlContent shouldNotContain "GeneratedJavaClass"
+                }
+        }
+
+        test("when suppressGeneratedFiles is false, generated files should be documented") {
+            val project = createProject(suppressGeneratedFiles = false)
+
+            project.runner
+                .addArguments(
+                    ":dokkaGeneratePublicationHtml",
+                    "--rerun-tasks",
+                    "--stacktrace",
+                )
+                .build {
+                    val htmlContent = project.projectDir
+                        .resolve("build/dokka/html/suppress-generated-files-false/[root]/index.html")
+                        .also(Path::shouldExist)
+                        .readText()
+                    htmlContent shouldContain "MyClass"
+                    htmlContent shouldContain "GeneratedClass"
+                    htmlContent shouldContain "GeneratedJavaClass"
+                }
+        }
+    }
+})
+
+private fun createProject(
+    suppressGeneratedFiles: Boolean
+): GradleProjectTest = gradleKtsProjectTest("suppress-generated-files-$suppressGeneratedFiles") {
+    buildGradleKts = """
+        |plugins {
+        |    kotlin("jvm") version embeddedKotlinVersion
+        |    id("org.jetbrains.dokka") version "$DOKKA_VERSION"
+        |}
+        |
+        |dokka {
+        |    dokkaSourceSets.configureEach {
+        |        suppressGeneratedFiles.set(${suppressGeneratedFiles})
+        |        // emulate generated sources added, for example by KSP
+        |        sourceRoots.from("build/generated")
+        |    }
+        |}
+        |""".trimMargin()
+
+    dir("src/main/kotlin") {
+        createKotlinFile(
+            "MyClass.kt",
+            """
+            |/**
+            | * A regular class that should be documented
+            | */
+            |class MyClass {
+            |    /**
+            |     * A function that should be documented
+            |     */
+            |    fun regularFunction() = "Hello"
+            |}
+            |""".trimMargin()
+        )
+    }
+
+    dir("build/generated/ksp/main") {
+        createKotlinFile(
+            "GeneratedClass.kt",
+            """
+            |/**
+            | * A generated class that should NOT be documented
+            | */
+            |class GeneratedClass {
+            |    /**
+            |     * A generated function that should NOT be documented
+            |     */
+            |    fun generatedFunction() = "Generated"
+            |}
+            |""".trimMargin()
+        )
+    }
+
+    dir("build/generated/apt/java/main") {
+        createFile(
+            "GeneratedJavaClass.java",
+            """
+            |/**
+            | * A generated Java class that should NOT be documented
+            | */
+            |public class GeneratedJavaClass {
+            |    /**
+            |     * A generated method that should NOT be documented
+            |     */
+            |    public String generatedMethod() {
+            |        return "Generated Java";
+            |    }
+            |}
+            |""".trimMargin()
+        )
+    }
+}