Automatically format generated files using ktlint if possible

gradle-plugin/gradle.properties

@@ -5,5 +5,7 @@ kotlinVersion = 2.1.0
 publishVersion = 1.3.0
 
 jacksonVersion = 2.18.2
+ktlintVersion = 1.5.0
+ec4jVersion = 1.1.0
 
 typescriptVersion = ^5.7.2

gradle-plugin/karakum-gradle-plugin/build.gradle.kts

@@ -12,6 +12,10 @@ dependencies {
     compileOnly(kotlin("gradle-plugin"))
 
     implementation(libs.jackson.databind)
+    implementation(libs.ktlint.ruleEngine)
+    implementation(libs.ktlint.ruleEngine.core)
+    implementation(libs.ktlint.ruleset.standard)
+    implementation(libs.ec4j)
 
     testImplementation(kotlin("test"))
 }

gradle-plugin/karakum-gradle-plugin/src/main/kotlin/io/github/sgrishchenko/karakum/gradle/plugin/KarakumPlugin.kt

@@ -1,18 +1,25 @@
 package io.github.sgrishchenko.karakum.gradle.plugin
 
+import io.github.sgrishchenko.karakum.gradle.plugin.service.KtLintService
 import io.github.sgrishchenko.karakum.gradle.plugin.tasks.KarakumConfig
 import io.github.sgrishchenko.karakum.gradle.plugin.tasks.KarakumGenerate
 import io.github.sgrishchenko.karakum.gradle.plugin.tasks.KarakumSync
 import org.gradle.api.Plugin
 import org.gradle.api.Project
 import org.gradle.api.file.FileTree
+import org.gradle.api.services.BuildServiceRegistry
 import org.gradle.kotlin.dsl.create
 import org.gradle.kotlin.dsl.getValue
 import org.gradle.kotlin.dsl.provideDelegate
+import org.gradle.kotlin.dsl.registerIfAbsent
 import org.gradle.kotlin.dsl.registering
 import org.jetbrains.kotlin.gradle.targets.js.npm.npmProject
+import javax.inject.Inject
+
+abstract class KarakumPlugin : Plugin<Project> {
+    @get:Inject
+    abstract val sharedServices: BuildServiceRegistry
 
-class KarakumPlugin : Plugin<Project> {
     override fun apply(project: Project): Unit = with(project) {
         plugins.withId("org.jetbrains.kotlin.multiplatform") {
             val karakum = extensions.create<KarakumExtension>("karakum").apply {
@@ -51,6 +58,8 @@ class KarakumPlugin : Plugin<Project> {
                 destinationDirectory.convention(layout.dir(npmProjectDirectory).map { it.dir("karakum") })
             }
 
+            sharedServices.registerIfAbsent("ktlintService", KtLintService::class)
+
             val generateKarakumExternals by tasks.registering(KarakumGenerate::class) {
                 group = KARAKUM_GRADLE_PLUGIN_GROUP
                 description = "Generates the Kotlin external declarations using Karakum."

gradle-plugin/karakum-gradle-plugin/src/main/kotlin/io/github/sgrishchenko/karakum/gradle/plugin/service/KtLintService.kt

@@ -0,0 +1,18 @@
+package io.github.sgrishchenko.karakum.gradle.plugin.service
+
+import com.pinterest.ktlint.rule.engine.api.KtLintRuleEngine
+import com.pinterest.ktlint.ruleset.standard.StandardRuleSetProvider
+import org.gradle.api.services.BuildService
+import org.gradle.api.services.BuildServiceParameters.None
+
+abstract class KtLintService : BuildService<None> {
+    val ktlint = KtLintRuleEngine(
+        ruleProviders = StandardRuleSetProvider().getRuleProviders()
+    ).apply {
+        // ktlint stores .editorconfig files in a companion object and thus as static state
+        // this is not good when running multiple builds within the same Gradle daemon
+        // and the .editorconfig file might have changed, so clear that cache
+        // so that .editorconfig files are read freshly
+        trimMemory()
+    }
+}

gradle-plugin/karakum-gradle-plugin/src/main/kotlin/io/github/sgrishchenko/karakum/gradle/plugin/tasks/KarakumGenerate.kt

@@ -5,17 +5,27 @@ import com.fasterxml.jackson.databind.node.ArrayNode
 import com.fasterxml.jackson.databind.node.ObjectNode
 import io.github.sgrishchenko.karakum.gradle.plugin.karakumDependency
 import io.github.sgrishchenko.karakum.gradle.plugin.kotlinJsCompilation
+import io.github.sgrishchenko.karakum.gradle.plugin.service.KtLintService
 import io.github.sgrishchenko.karakum.gradle.plugin.typescriptDependency
+import io.github.sgrishchenko.karakum.gradle.plugin.worker.KtLintFormatWorker
+import org.ec4j.core.Resource.Resources
+import org.ec4j.core.ResourcePropertiesService
 import org.gradle.api.DefaultTask
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.file.ProjectLayout
 import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.provider.Property
+import org.gradle.api.services.ServiceReference
 import org.gradle.api.tasks.*
+import org.gradle.kotlin.dsl.submit
 import org.gradle.process.ExecOperations
+import org.gradle.workers.WorkerExecutor
 import org.jetbrains.kotlin.gradle.targets.js.ir.KotlinJsIrCompilation
 import org.jetbrains.kotlin.gradle.targets.js.npm.RequiresNpmDependencies
 import org.jetbrains.kotlin.gradle.targets.js.npm.npmProject
+import java.nio.file.Path
 import javax.inject.Inject
+import kotlin.text.Charsets.UTF_8
 
 abstract class KarakumGenerate : DefaultTask(), RequiresNpmDependencies {
     @get:Inject
@@ -24,6 +34,12 @@ abstract class KarakumGenerate : DefaultTask(), RequiresNpmDependencies {
     @get:Inject
     abstract val layout: ProjectLayout
 
+    @get:Inject
+    abstract val workerExecutor: WorkerExecutor
+
+    @get:ServiceReference
+    abstract val ktlintService: Property<KtLintService>
+
     @get:InputFile
     abstract val configFile: RegularFileProperty
 
@@ -71,6 +87,18 @@ abstract class KarakumGenerate : DefaultTask(), RequiresNpmDependencies {
         }
     }
 
+    @get:InputFiles
+    @get:Optional
+    val editorConfigFiles = destinationDirectory.map { destinationDirectory ->
+        ResourcePropertiesService
+            .builder()
+            .build()
+            .queryProperties(Resources.ofPath(destinationDirectory.asFile.absoluteFile.toPath(), UTF_8))
+            .editorConfigFiles
+            .map { it.getAdapter(Path::class.java) }
+            .let { layout.files(it) }
+    }
+
     @TaskAction
     fun generate() {
         exec.exec {
@@ -80,5 +108,12 @@ abstract class KarakumGenerate : DefaultTask(), RequiresNpmDependencies {
                 args = listOf("--config", configFile.get().asFile.absolutePath)
             )
         }
+
+        logger.lifecycle("Formatting generated files")
+        destinationDirectory.get().asFileTree.forEach { file ->
+            workerExecutor.noIsolation().submit(KtLintFormatWorker::class) {
+                this.file.set(file)
+            }
+        }
     }
 }

gradle-plugin/karakum-gradle-plugin/src/main/kotlin/io/github/sgrishchenko/karakum/gradle/plugin/worker/KtLintFormatWorker.kt

@@ -0,0 +1,41 @@
+package io.github.sgrishchenko.karakum.gradle.plugin.worker
+
+import com.pinterest.ktlint.rule.engine.api.Code
+import com.pinterest.ktlint.rule.engine.core.api.AutocorrectDecision.ALLOW_AUTOCORRECT
+import com.pinterest.ktlint.rule.engine.core.api.AutocorrectDecision.NO_AUTOCORRECT
+import io.github.sgrishchenko.karakum.gradle.plugin.service.KtLintService
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.logging.Logging
+import org.gradle.api.provider.Property
+import org.gradle.api.services.ServiceReference
+import org.gradle.workers.WorkAction
+import org.gradle.workers.WorkParameters
+
+abstract class KtLintFormatWorker : WorkAction<KtLintFormatWorker.Parameters> {
+    private val logger = Logging.getLogger(KtLintFormatWorker::class.java)
+
+    @get:ServiceReference
+    abstract val ktlintService: Property<KtLintService>
+
+    override fun execute() {
+        val file = parameters.file.get().asFile
+        logger.info("Formatting ${file.absolutePath}")
+        runCatching {
+            ktlintService
+                .get()
+                .ktlint
+                .format(Code.fromFile(file)) { lintError ->
+                    if (lintError.canBeAutoCorrected) ALLOW_AUTOCORRECT else NO_AUTOCORRECT
+                }.also(file::writeText)
+        }.onFailure {
+            logger.info("Formatting failed for ${file.absolutePath}")
+            logger.info(it.stackTraceToString())
+        }.onSuccess {
+            logger.info("Formatting successful for ${file.absolutePath}")
+        }
+    }
+
+    interface Parameters : WorkParameters {
+        val file: RegularFileProperty
+    }
+}

gradle-plugin/settings.gradle.kts

@@ -15,6 +15,12 @@ dependencyResolutionManagement {
         val libs by creating {
             val jacksonVersion: String by settings
             library("jackson-databind", "com.fasterxml.jackson.core", "jackson-databind").version(jacksonVersion)
+            val ktlintVersion: String by settings
+            library("ktlint-ruleEngine", "com.pinterest.ktlint", "ktlint-rule-engine").version(ktlintVersion)
+            library("ktlint-ruleEngine-core", "com.pinterest.ktlint", "ktlint-rule-engine-core").version(ktlintVersion)
+            library("ktlint-ruleset-standard", "com.pinterest.ktlint", "ktlint-ruleset-standard").version(ktlintVersion)
+            val ec4jVersion: String by settings
+            library("ec4j", "org.ec4j.core", "ec4j-core").version(ec4jVersion)
         }
     }
 }