Clear ktlint caches when .editorconfig changes

src/main/kotlin/org/jmailen/gradle/kotlinter/support/EditorConfigUtils.kt

@@ -0,0 +1,55 @@
+package org.jmailen.gradle.kotlinter.support
+
+import com.pinterest.ktlint.core.KtLint
+import com.pinterest.ktlint.core.api.DefaultEditorConfigProperties
+import com.pinterest.ktlint.core.api.EditorConfigOverride
+import org.gradle.api.file.ProjectLayout
+import org.gradle.api.logging.Logger
+import org.gradle.api.provider.Property
+import java.io.File
+
+internal fun editorConfigOverride(ktLintParams: KtLintParams): EditorConfigOverride {
+    val rules = ktLintParams.disabledRules
+
+    return if (rules.isEmpty()) {
+        EditorConfigOverride.emptyEditorConfigOverride
+    } else {
+        EditorConfigOverride.from(DefaultEditorConfigProperties.disabledRulesProperty to rules.joinToString(separator = ","))
+    }
+}
+
+internal fun resetEditorconfigCacheIfNeeded(
+    wasEditorConfigChanged: Property<Boolean>,
+    logger: Logger,
+) {
+    if (wasEditorConfigChanged.get()) {
+        logger.info("Editorconfig changed, resetting KtLint caches")
+        KtLint.trimMemory() // Calling trimMemory() will also reset internal loaded `.editorconfig` cache
+    }
+}
+
+internal fun ProjectLayout.findApplicableEditorConfigFiles(): Sequence<File> {
+    val projectEditorConfig = projectDirectory.file(".editorconfig").asFile
+
+    return generateSequence(seed = projectEditorConfig) { editorconfig ->
+        if (editorconfig.isRootEditorConfig) {
+            null
+        } else {
+            editorconfig.parentFile?.parentFile?.resolve(".editorconfig")
+        }
+    }
+}
+
+private val File.isRootEditorConfig: Boolean
+    get() {
+        if (!isFile || !canRead()) return false
+
+        return useLines { lines ->
+            lines.any { line -> line.matches(editorConfigRootRegex) }
+        }
+    }
+
+/**
+ * According to https://editorconfig.org/ root-most EditorConfig file contains line with `root=true`
+ */
+private val editorConfigRootRegex = "^root\\s?=\\s?true".toRegex()

src/main/kotlin/org/jmailen/gradle/kotlinter/tasks/ConfigurableKtLintTask.kt

@@ -13,9 +13,12 @@ import org.gradle.api.tasks.PathSensitive
 import org.gradle.api.tasks.PathSensitivity
 import org.gradle.api.tasks.SourceTask
 import org.gradle.internal.exceptions.MultiCauseException
+import org.gradle.work.Incremental
+import org.gradle.work.InputChanges
 import org.jmailen.gradle.kotlinter.KotlinterExtension.Companion.DEFAULT_DISABLED_RULES
 import org.jmailen.gradle.kotlinter.KotlinterExtension.Companion.DEFAULT_EXPERIMENTAL_RULES
 import org.jmailen.gradle.kotlinter.support.KtLintParams
+import org.jmailen.gradle.kotlinter.support.findApplicableEditorConfigFiles
 
 abstract class ConfigurableKtLintTask(
     projectLayout: ProjectLayout,
@@ -30,6 +33,7 @@ abstract class ConfigurableKtLintTask(
 
     @get:InputFiles
     @get:PathSensitive(PathSensitivity.RELATIVE)
+    @get:Incremental
     internal val editorconfigFiles: FileCollection = objectFactory.fileCollection().apply {
         from(projectLayout.findApplicableEditorConfigFiles().toList())
     }
@@ -39,6 +43,9 @@ abstract class ConfigurableKtLintTask(
         experimentalRules = experimentalRules.get(),
         disabledRules = disabledRules.get()
     )
+
+    protected fun wasEditorconfigChanged(inputChanges: InputChanges) =
+        inputChanges.isIncremental && inputChanges.getFileChanges(editorconfigFiles).any()
 }
 
 internal inline fun <reified T> ObjectFactory.property(default: T? = null): Property<T> =

src/main/kotlin/org/jmailen/gradle/kotlinter/tasks/FormatTask.kt

@@ -7,6 +7,7 @@ import org.gradle.api.model.ObjectFactory
 import org.gradle.api.tasks.Optional
 import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.TaskAction
+import org.gradle.work.InputChanges
 import org.gradle.workers.WorkerExecutor
 import org.jetbrains.kotlin.utils.addToStdlib.ifNotEmpty
 import org.jmailen.gradle.kotlinter.support.KotlinterError
@@ -31,14 +32,15 @@ open class FormatTask @Inject constructor(
     }
 
     @TaskAction
-    fun run() {
+    fun run(inputChanges: InputChanges) {
         val result = with(workerExecutor.noIsolation()) {
             submit(FormatWorkerAction::class.java) { p ->
                 p.name.set(name)
                 p.files.from(source)
                 p.projectDirectory.set(projectLayout.projectDirectory.asFile)
                 p.ktLintParams.set(getKtLintParams())
                 p.output.set(report)
+                p.wasEditorConfigChanged.set(wasEditorconfigChanged(inputChanges))
             }
             runCatching { await() }
         }

src/main/kotlin/org/jmailen/gradle/kotlinter/tasks/LintTask.kt

@@ -13,6 +13,7 @@ import org.gradle.api.tasks.OutputFiles
 import org.gradle.api.tasks.PathSensitive
 import org.gradle.api.tasks.PathSensitivity
 import org.gradle.api.tasks.TaskAction
+import org.gradle.work.InputChanges
 import org.gradle.workers.WorkerExecutor
 import org.jetbrains.kotlin.utils.addToStdlib.ifNotEmpty
 import org.jmailen.gradle.kotlinter.KotlinterExtension.Companion.DEFAULT_IGNORE_FAILURES
@@ -43,14 +44,15 @@ open class LintTask @Inject constructor(
     val ignoreFailures: Property<Boolean> = objectFactory.property(default = DEFAULT_IGNORE_FAILURES)
 
     @TaskAction
-    fun run() {
+    fun run(inputChanges: InputChanges) {
         val result = with(workerExecutor.noIsolation()) {
             submit(LintWorkerAction::class.java) { p ->
                 p.name.set(name)
                 p.files.from(source)
                 p.projectDirectory.set(projectLayout.projectDirectory.asFile)
                 p.reporters.putAll(reports)
                 p.ktLintParams.set(getKtLintParams())
+                p.wasEditorConfigChanged.set(wasEditorconfigChanged(inputChanges))
             }
             runCatching { await() }
         }

src/main/kotlin/org/jmailen/gradle/kotlinter/tasks/format/FormatWorkerAction.kt

@@ -12,6 +12,7 @@ import org.jmailen.gradle.kotlinter.support.KotlinterError
 import org.jmailen.gradle.kotlinter.support.KtLintParams
 import org.jmailen.gradle.kotlinter.support.defaultRuleSetProviders
 import org.jmailen.gradle.kotlinter.support.editorConfigOverride
+import org.jmailen.gradle.kotlinter.support.resetEditorconfigCacheIfNeeded
 import org.jmailen.gradle.kotlinter.support.resolveRuleSets
 import org.jmailen.gradle.kotlinter.tasks.FormatTask
 import java.io.File
@@ -25,6 +26,11 @@ abstract class FormatWorkerAction : WorkAction<FormatWorkerParameters> {
     private val output: File? = parameters.output.asFile.orNull
 
     override fun execute() {
+        resetEditorconfigCacheIfNeeded(
+            wasEditorConfigChanged = parameters.wasEditorConfigChanged,
+            logger = logger,
+        )
+
         val fixes = mutableListOf<String>()
         try {
             files.forEach { file ->

src/main/kotlin/org/jmailen/gradle/kotlinter/tasks/format/FormatWorkerParameters.kt

@@ -8,6 +8,7 @@ import org.jmailen.gradle.kotlinter.support.KtLintParams
 
 interface FormatWorkerParameters : WorkParameters {
     val name: Property<String>
+    val wasEditorConfigChanged: Property<Boolean>
     val files: ConfigurableFileCollection
     val projectDirectory: RegularFileProperty
     val ktLintParams: Property<KtLintParams>

src/main/kotlin/org/jmailen/gradle/kotlinter/tasks/lint/LintWorkerAction.kt

@@ -15,6 +15,7 @@ import org.jmailen.gradle.kotlinter.support.defaultRuleSetProviders
 import org.jmailen.gradle.kotlinter.support.editorConfigOverride
 import org.jmailen.gradle.kotlinter.support.reporterFor
 import org.jmailen.gradle.kotlinter.support.reporterPathFor
+import org.jmailen.gradle.kotlinter.support.resetEditorconfigCacheIfNeeded
 import org.jmailen.gradle.kotlinter.support.resolveRuleSets
 import org.jmailen.gradle.kotlinter.tasks.LintTask
 import java.io.File
@@ -30,6 +31,10 @@ abstract class LintWorkerAction : WorkAction<LintWorkerParameters> {
     private val ktLintParams: KtLintParams = parameters.ktLintParams.get()
 
     override fun execute() {
+        resetEditorconfigCacheIfNeeded(
+            wasEditorConfigChanged = parameters.wasEditorConfigChanged,
+            logger = logger,
+        )
         var hasError = false
 
         try {

src/main/kotlin/org/jmailen/gradle/kotlinter/tasks/lint/LintWorkerParameters.kt

@@ -10,6 +10,7 @@ import java.io.File
 
 interface LintWorkerParameters : WorkParameters {
     val name: Property<String>
+    val wasEditorConfigChanged: Property<Boolean>
     val files: ConfigurableFileCollection
     val projectDirectory: RegularFileProperty
     val reporters: MapProperty<String, File>

src/test/kotlin/org/jmailen/gradle/kotlinter/functional/EditorConfigTest.kt

@@ -6,6 +6,7 @@ import org.jmailen.gradle.kotlinter.functional.utils.kotlinClass
 import org.jmailen.gradle.kotlinter.functional.utils.resolve
 import org.jmailen.gradle.kotlinter.functional.utils.settingsFile
 import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
 import org.junit.Assert.assertTrue
 import org.junit.Before
 import org.junit.Test
@@ -100,18 +101,59 @@ internal class EditorConfigTest : WithGradleTest.Kotlin() {
             assertTrue(output.contains("[indent] Unexpected indentation (2) (should be 6)"))
         }
     }
+
     @Test
-    fun `editorconfig changes are taken into account on task re-runs`() {
+    fun `editorconfig changes are taken into account on lint task re-runs`() {
         projectRoot.resolve(".editorconfig") {
-            writeText(editorConfig)
+            writeText(
+                """
+                    [*.{kt,kts}]
+                    disabled_rules=filename
+                """.trimIndent(),
+            )
         }
-
         projectRoot.resolve("src/main/kotlin/FileName.kt") {
             writeText(kotlinClass("DifferentClassName"))
         }
-        buildAndFail("lintKotlin").apply {
+        build("lintKotlin").apply {
+            assertEquals(TaskOutcome.SUCCESS, task(":lintKotlinMain")?.outcome)
+            assertFalse(output.contains("resetting KtLint caches"))
+        }
+
+        projectRoot.resolve(".editorconfig") {
+            writeText(editorConfig)
+        }
+        buildAndFail("lintKotlin", "--info").apply {
             assertEquals(TaskOutcome.FAILED, task(":lintKotlinMain")?.outcome)
             assertTrue(output.contains("[filename] File 'FileName.kt' contains a single top level declaration"))
+            assertTrue(output.contains("resetting KtLint caches"))
+        }
+
+        projectRoot.resolve("src/main/kotlin/FileName.kt") {
+            writeText(kotlinClass("FileName"))
+        }
+        build("lintKotlin").apply {
+            assertEquals(TaskOutcome.SUCCESS, task(":lintKotlinMain")?.outcome)
+            assertFalse(output.contains("resetting KtLint caches"))
+        }
+        build("lintKotlin").apply {
+            assertEquals(TaskOutcome.UP_TO_DATE, task(":lintKotlinMain")?.outcome)
+            assertFalse(output.contains("resetting KtLint caches"))
+        }
+    }
+
+    @Test
+    fun `editorconfig changes are ignored for format task re-runs`() {
+        projectRoot.resolve(".editorconfig") {
+            writeText(editorConfig)
+        }
+
+        projectRoot.resolve("src/main/kotlin/FileName.kt") {
+            writeText(kotlinClass("DifferentClassName"))
+        }
+        build("formatKotlin").apply {
+            assertEquals(TaskOutcome.SUCCESS, task(":formatKotlinMain")?.outcome)
+            assertTrue(output.contains("Format could not fix > [filename] File 'FileName.kt' contains a single top level declaration"))
         }
 
         projectRoot.resolve(".editorconfig") {
@@ -122,8 +164,10 @@ internal class EditorConfigTest : WithGradleTest.Kotlin() {
                 """.trimIndent(),
             )
         }
-        build("lintKotlin").apply {
-            assertEquals(TaskOutcome.SUCCESS, task(":lintKotlinMain")?.outcome)
+        build("formatKotlin", "--info").apply {
+            assertEquals(TaskOutcome.SUCCESS, task(":formatKotlinMain")?.outcome)
+            assertTrue(output.contains("Format could not fix"))
+            assertFalse(output.contains("resetting KtLint caches"))
         }
     }
 }