Rename sensitive flag to isTransient and inverse logic, add file outputs

isTransient with default value as false makes it a bit more readable
Some Compiler Plugins can use file outputs properties to dump some data
there and gradle can support incremental build
with file outputs.

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/KpmCompilerPluginIT.kt

@@ -11,13 +11,13 @@ import kotlin.test.assertTrue
 class KpmCompilerPluginIT : BaseGradleIT() {
 
     @Test
-    fun testSensitivePluginOptions() {
-        val project = transformProjectWithPluginsDsl("kpmSensitivePluginOptions")
-        fun updatePluginOptions(sensitiveValue: String, insensitiveValue: String) {
+    fun testTransientPluginOptions() {
+        val project = transformProjectWithPluginsDsl("kpmTransientPluginOptions")
+        fun updatePluginOptions(regularOptionValue: String, transientOptionValue: String) {
             project.gradleProperties().writeText(
                 """
-                    test-plugin.sensitive=$sensitiveValue
-                    test-plugin.insensitive=$insensitiveValue
+                    test-plugin.regular=$regularOptionValue
+                    test-plugin.transient=$transientOptionValue
                     """.trimIndent()
             )
         }
@@ -28,36 +28,36 @@ class KpmCompilerPluginIT : BaseGradleIT() {
             assertTasksExecuted(":compileKotlinJvm")
             compilerArgs(":compileKotlinJvm").also { args ->
                 assertTrue(
-                    args.contains("plugin:test-plugin:sensitive=XXX"),
-                    "Expected sensitive plugin option in compilation args"
+                    args.contains("plugin:test-plugin:regular=XXX"),
+                    "Expected regular plugin option in compilation args"
                 )
                 assertTrue(
-                    args.contains("plugin:test-plugin:insensitive=YYY"),
-                    "Expected insensitive plugin option in compilation args"
+                    args.contains("plugin:test-plugin:transient=YYY"),
+                    "Expected transient plugin option in compilation args"
                 )
             }
         }
 
-        // When insensitive plugin option change
+        // When transient plugin option change
         updatePluginOptions("XXX", "ZZZ")
         project.build("compileKotlin") {
             assertSuccessful()
             assertTasksUpToDate(":compileKotlinJvm")
         }
 
-        // When sensitive plugin option change
+        // When regular plugin option change
         updatePluginOptions("ZZZ", "ZZZ")
         project.build("compileKotlin") {
             assertSuccessful()
             assertTasksExecuted(":compileKotlinJvm")
             compilerArgs(":compileKotlinJvm").also { args ->
                 assertTrue(
-                    args.contains("plugin:test-plugin:sensitive=ZZZ"),
-                    "Expected sensitive plugin option in compilation args"
+                    args.contains("plugin:test-plugin:regular=ZZZ"),
+                    "Expected regular plugin option in compilation args"
                 )
                 assertTrue(
-                    args.contains("plugin:test-plugin:insensitive=ZZZ"),
-                    "Expected insensitive plugin option in compilation args"
+                    args.contains("plugin:test-plugin:transient=ZZZ"),
+                    "Expected transient plugin option in compilation args"
                 )
             }
         }

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/kpmSensitivePluginOptions/gradle.properties

@@ -1,2 +0,0 @@
-test-plugin.sensitive=SENSITIVE_VALUE
-test-plugin.insensitive=INSENSITIVE_VALUE

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/kpmSensitivePluginOptions/settings.gradle.kts

@@ -1,12 +0,0 @@
-pluginManagement {
-    repositories {
-        mavenLocal()
-        mavenCentral()
-    }
-
-    plugins {
-        kotlin("multiplatform.pm20").version("1.5.255-SNAPSHOT")
-    }
-}
-
-rootProject.name = "kpmSensitivePluginOptions"

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/kpmSensitivePluginOptions/src/jvmMain/kotlin/Foo.kt

@@ -1,4 +0,0 @@
-package testProject.kpmSensitivePluginOptions
-
-class Foo {
-}

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/kpmTransientPluginOptions/build.gradle.kts

@@ -1,5 +1,4 @@
 import org.gradle.api.Project
-import org.gradle.api.plugins.ExtraPropertiesExtension
 import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.*
 import org.jetbrains.kotlin.project.model.*
 
@@ -12,7 +11,7 @@ repositories {
     mavenLocal()
 }
 
-plugins.apply(GradleKpmPluginWithSensitivePluginOptions::class.java)
+plugins.apply(GradleKpmPluginWithTransientPluginOptions::class.java)
 
 configure<KotlinPm20ProjectExtension> {
     main {
@@ -20,17 +19,17 @@ configure<KotlinPm20ProjectExtension> {
     }
 }
 
-class KpmPluginWithSensitivePluginOptions(
-    private val sensitiveOptionValue: String,
-    private val insensitiveOptionValue: String
+class KpmPluginWithTransientPluginOptions(
+    private val regularOptionValue: String,
+    private val transientOptionValue: String
 ) : KpmCompilerPlugin {
     private fun pluginData() = PluginData(
         pluginId = "test-plugin",
         // allopen artifact is used to avoid boilerplate with cooking custom compiler plugin
         artifact = PluginData.ArtifactCoordinates("org.jetbrains.kotlin", "kotlin-allopen"),
         options = listOf(
-            StringOption("sensitive", sensitiveOptionValue, true),
-            StringOption("insensitive", insensitiveOptionValue, false)
+            StringOption("regular", regularOptionValue, isTransient = false),
+            StringOption("transient", transientOptionValue, isTransient = true)
         )
     )
 
@@ -39,7 +38,7 @@ class KpmPluginWithSensitivePluginOptions(
     override fun forPlatformCompilation(variant: KotlinModuleVariant) = pluginData()
 }
 
-class GradleKpmPluginWithSensitivePluginOptions : GradleKpmCompilerPlugin {
+class GradleKpmPluginWithTransientPluginOptions : GradleKpmCompilerPlugin {
     private lateinit var project: Project
 
     override fun apply(target: Project) {
@@ -47,9 +46,9 @@ class GradleKpmPluginWithSensitivePluginOptions : GradleKpmCompilerPlugin {
     }
 
     override val kpmCompilerPlugin by lazy {
-        KpmPluginWithSensitivePluginOptions(
-            sensitiveOptionValue = project.property("test-plugin.sensitive") as String,
-            insensitiveOptionValue = project.property("test-plugin.insensitive") as String
+        KpmPluginWithTransientPluginOptions(
+            regularOptionValue = project.property("test-plugin.regular") as String,
+            transientOptionValue = project.property("test-plugin.transient") as String
         )
     }
 }

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/kpmTransientPluginOptions/gradle.properties

@@ -0,0 +1,2 @@
+test-plugin.regular=REGULAR_VALUE
+test-plugin.transient=TRANSIENT_VALUE

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/kpmTransientPluginOptions/settings.gradle.kts

@@ -0,0 +1,13 @@
+pluginManagement {
+    repositories {
+        mavenLocal()
+        mavenCentral()
+    }
+
+    plugins {
+        val kotlin_version: String by settings
+        kotlin("multiplatform.pm20").version(kotlin_version)
+    }
+}
+
+rootProject.name = "kpmTransientPluginOptions"

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/kpmTransientPluginOptions/src/jvmMain/kotlin/Foo.kt

@@ -0,0 +1,4 @@
+package testProject.kpmTransientPluginOptions
+
+class Foo {
+}

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/pm20/GradleKpmCompilerPlugin.kt

@@ -53,6 +53,7 @@ internal class CompilerPluginOptionsBuilder(
     private val artifacts = mutableListOf<String>()
     private val gradleInputs = mutableMapOf<String, MutableList<String>>()
     private val gradleInputFiles = mutableSetOf<File>()
+    private val gradleOutputFiles = mutableSetOf<File>()
 
     operator fun plusAssign(pluginData: PluginData) {
         artifacts += pluginData.artifact.toGradleCoordinates()
@@ -60,8 +61,8 @@ internal class CompilerPluginOptionsBuilder(
         for (option in pluginData.options) {
             pluginOptions.addPluginArgument(pluginData.pluginId, option.toSubpluginOption())
 
-            if (option.sensitive) {
-                addToInputs(pluginData.pluginId, option)
+            if (!option.isTransient) {
+                addToInputsOutputs(pluginData.pluginId, option)
             }
         }
     }
@@ -72,9 +73,14 @@ internal class CompilerPluginOptionsBuilder(
         }
     }
 
-    private fun addToInputs(pluginId: String, option: PluginOption) {
-        when(option) {
-            is FilesOption -> gradleInputFiles += option.files
+    private fun addToInputsOutputs(pluginId: String, option: PluginOption) {
+        when (option) {
+            is FilesOption ->
+                if (option.isOutput) {
+                    gradleOutputFiles += option.files
+                } else {
+                    gradleInputFiles += option.files
+                }
             is StringOption -> gradleInputs
                 .getOrPut("${pluginId}.${option.key}") { mutableListOf() }
                 .add(option.value)
@@ -93,12 +99,15 @@ internal class CompilerPluginOptionsBuilder(
         return KotlinCompilerPluginData(
             classpath = pluginClasspathConfiguration,
             options = pluginOptions,
-            inputs = gradleInputs.flattenWithIndex(),
-            inputFiles = gradleInputFiles
+            inputsOutputsState = KotlinCompilerPluginData.InputsOutputsState(
+                inputs = gradleInputs.flattenWithIndex(),
+                inputFiles = gradleInputFiles,
+                outputFiles = gradleOutputFiles
+            )
         )
     }
 
-    private fun Map<String,List<String>>.flattenWithIndex(): Map<String, String> {
+    private fun Map<String, List<String>>.flattenWithIndex(): Map<String, String> {
         val result = mutableMapOf<String, String>()
 
         for ((key, values) in this) {
@@ -116,5 +125,5 @@ internal class CompilerPluginOptionsBuilder(
     }
 
     private fun PluginData.ArtifactCoordinates.toGradleCoordinates(): String =
-        "$group:$artifact:${version ?: project.getKotlinPluginVersion()}"
+        listOfNotNull(group, artifact, version).joinToString(":")
 }

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/tasks/Tasks.kt

@@ -788,14 +788,19 @@ data class KotlinCompilerPluginData(
     /**
      * Used only for Up-to-date checks
      */
-    @get:Input
-    val inputs: Map<String, String>,
+    @get:Nested
+    val inputsOutputsState: InputsOutputsState
+) {
+    data class InputsOutputsState(
+        @get:Input
+        val inputs: Map<String, String>,
 
-    /**
-     * Used only for Up-to-date checks
-     */
-    @get:InputFiles
-    @get:PathSensitive(PathSensitivity.RELATIVE)
-    val inputFiles: Set<File>
-)
+        @get:InputFiles
+        @get:PathSensitive(PathSensitivity.RELATIVE)
+        val inputFiles: Set<File>,
+
+        @get:OutputFiles
+        val outputFiles: Set<File>
+    )
+}
 

libraries/tools/kotlin-project-model/src/main/kotlin/KpmCompilerPlugin.kt

@@ -53,22 +53,28 @@ sealed class PluginOption {
     abstract val key: String
 
     /**
-     * when true a value of given plugin option is sensitive for incremental compilation
-     * when false compilation task can be skipped even if value differs from previous one
+     * Indicates whether value of [PluginOption] should be stored for incremental build checks.
+     * Value changes of non-transient [PluginOption] will invalidate incremental caches.
      */
-    abstract val sensitive: Boolean
+    abstract val isTransient: Boolean
 }
 
 data class StringOption(
     override val key: String,
     val value: String,
-    override val sensitive: Boolean = true
+    override val isTransient: Boolean = false
 ) : PluginOption()
 
 data class FilesOption(
     override val key: String,
     val files: List<File>,
-    override val sensitive: Boolean = true
+    /**
+     * Indicates whether FilesOption is used as input or output during compilation
+     * false means input
+     * true means output
+     */
+    val isOutput: Boolean = false,
+    override val isTransient: Boolean = false
 ) : PluginOption()
 
 // TODO: It should be part of "Compilation Process": KotlinModule.compilationRequestFor(METADATA | PLATFORM) -> CompilationRequest