Fix the localToProject attribute schema for Gradle 4.10.2+

In Gradle 4.10.2, a change was made in the attributes disambiguation
process: if some of the candidates have a single attribute value and
others don't have that attribute (i.e. have a null value), the
disambiguation rule for that attribute doesn't get called.
Effectively, null values are excluded from disambiguation, but still may
cause ambiguity (sic!)

See: https://github.com/gradle/gradle/issues/6747#issuecomment-445921139

This change affected our attribute `localToProject` that we use to
disambiguate the deprecated but still consumable configurations like
`compile`, `runtime`, `testCompile`, `testRuntime` from those
configurations which should have priority during project dependency
resolution: the `*Element` ones. Our scheme marked the former
configurations with the attribute and the latter were not marked, with
a disambiguation rule that preferred null values.

To fix this logic with Gradle 4.10.2, we instead mark both kinds of
configurations with the attribute, which now has a value 'public'
that is preferred by the rule over the other values. We also make sure
that the attribute doesn't leak into the published Gradle metadata, as
it is only needed for project-to-project dependencies resolution.

Issue #KT-28795 Fixed

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

@@ -4,6 +4,7 @@
  */
 package org.jetbrains.kotlin.gradle
 
+import org.jetbrains.kotlin.gradle.plugin.ProjectLocalConfigurations
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinMultiplatformPlugin
 import org.jetbrains.kotlin.gradle.plugin.mpp.UnusedSourceSetsChecker
 import org.jetbrains.kotlin.gradle.plugin.sources.METADATA_CONFIGURATION_NAME_SUFFIX
@@ -75,6 +76,9 @@ class NewMultiplatformIT : BaseGradleIT() {
                     Assert.assertTrue("$it should exist", groupDir.resolve(it).exists())
                 }
 
+                val gradleMetadata = groupDir.resolve("sample-lib/1.0/sample-lib-1.0.module").readText()
+                assertFalse(gradleMetadata.contains(ProjectLocalConfigurations.ATTRIBUTE.name))
+
                 listOf(jvmJarName, jsJarName, metadataJarName, wasmKlibName, nativeKlibName).forEach {
                     val pom = groupDir.resolve(it.replaceAfterLast('.', "pom"))
                     Assert.assertTrue(

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

@@ -448,11 +448,13 @@ internal abstract class AbstractKotlinPlugin(
             if (kotlinTarget.platformType != KotlinPlatformType.common) {
                 project.configurations.getByName(kotlinTarget.apiElementsConfigurationName).run {
                     attributes.attribute(Usage.USAGE_ATTRIBUTE, KotlinUsages.producerApiUsage(kotlinTarget))
+                    setupAsPublicConfigurationIfSupported(kotlinTarget)
                     usesPlatformOf(kotlinTarget)
                 }
 
                 project.configurations.getByName(kotlinTarget.runtimeElementsConfigurationName).run {
                     attributes.attribute(Usage.USAGE_ATTRIBUTE, KotlinUsages.producerRuntimeUsage(kotlinTarget))
+                    setupAsPublicConfigurationIfSupported(kotlinTarget)
                     usesPlatformOf(kotlinTarget)
                 }
             }

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

@@ -187,6 +187,7 @@ abstract class AbstractKotlinTargetConfigurator<KotlinTargetType : KotlinTarget>
                 extendsFrom(runtimeConfiguration)
             }
             usesPlatformOf(target)
+            setupAsPublicConfigurationIfSupported(target)
         }
 
         if (mainCompilation is KotlinCompilationToRunnableFiles<*>) {
@@ -199,6 +200,7 @@ abstract class AbstractKotlinTargetConfigurator<KotlinTargetType : KotlinTarget>
                 val runtimeConfiguration = configurations.maybeCreate(mainCompilation.deprecatedRuntimeConfigurationName)
                 extendsFrom(implementationConfiguration, runtimeOnlyConfiguration, runtimeConfiguration)
                 usesPlatformOf(target)
+                setupAsPublicConfigurationIfSupported(target)
             }
             defaultConfiguration.extendsFrom(runtimeElementsConfiguration)
         } else {

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

@@ -10,8 +10,11 @@ import org.gradle.api.attributes.*
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinWithJavaTarget
 import org.jetbrains.kotlin.gradle.utils.isGradleVersionAtLeast
 
-internal object ProjectLocalConfigurations {
-    val ATTRIBUTE = Attribute.of("org.jetbrains.kotlin.localToProject", String::class.java)
+object ProjectLocalConfigurations {
+    val ATTRIBUTE: Attribute<String> = Attribute.of("org.jetbrains.kotlin.localToProject", String::class.java)
+
+    const val PUBLIC_VALUE = "public"
+    const val LOCAL_TO_PROJECT_PREFIX = "local to "
 
     fun setupAttributesMatchingStrategy(attributesSchema: AttributesSchema) = with(attributesSchema) {
         attribute(ATTRIBUTE) {
@@ -30,9 +33,8 @@ internal object ProjectLocalConfigurations {
 
     class ProjectLocalDisambiguation : AttributeDisambiguationRule<String> {
         override fun execute(details: MultipleCandidatesDetails<String?>) = with(details) {
-            if (candidateValues.contains(null)) {
-                @Suppress("NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS")
-                closestMatch(null as String?)
+            if (candidateValues.contains(PUBLIC_VALUE)) {
+                closestMatch(PUBLIC_VALUE)
             }
         }
     }
@@ -46,7 +48,15 @@ internal fun Configuration.setupAsLocalTargetSpecificConfigurationIfSupported(ta
         (target !is KotlinWithJavaTarget<*> || target.platformType != KotlinPlatformType.common)
     ) {
         usesPlatformOf(target)
-        attributes.attribute(ProjectLocalConfigurations.ATTRIBUTE, target.project.path)
+        attributes.attribute(ProjectLocalConfigurations.ATTRIBUTE, ProjectLocalConfigurations.LOCAL_TO_PROJECT_PREFIX + target.project.path)
+    }
+}
+
+internal fun Configuration.setupAsPublicConfigurationIfSupported(target: KotlinTarget) {
+    if (gradleVersionSupportsAttributeRules &&
+        (target !is KotlinWithJavaTarget<*> || target.platformType != KotlinPlatformType.common)
+    ) {
+        attributes.attribute(ProjectLocalConfigurations.ATTRIBUTE, ProjectLocalConfigurations.PUBLIC_VALUE)
     }
 }
 

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

@@ -20,19 +20,25 @@ import org.gradle.api.attributes.AttributeContainer
 import java.util.*
 
 // TODO better implementation: attribute invariants (no attrs with same name and different types allowed), thread safety?
-class HierarchyAttributeContainer(val parent: AttributeContainer?) : AttributeContainer {
+class HierarchyAttributeContainer(
+    val parent: AttributeContainer?,
+    val filterParentAttributes: (Attribute<*>) -> Boolean = { true }
+) : AttributeContainer {
     private val attributesMap = Collections.synchronizedMap(mutableMapOf<Attribute<*>, Any>())
 
+    private fun getFilteredParentAttribute(key: Attribute<*>) =
+        if (parent != null && filterParentAttributes(key)) parent.getAttribute(key) else null
+
     override fun contains(key: Attribute<*>): Boolean =
-        attributesMap.contains(key) || parent?.contains(key) ?: false
+        attributesMap.contains(key) || getFilteredParentAttribute(key) != null
 
     @Suppress("UNCHECKED_CAST")
     override fun <T : Any?> getAttribute(key: Attribute<T>?): T? =
-        attributesMap.get(key as Attribute<*>) as T? ?: parent?.getAttribute(key)
+        attributesMap.get(key as Attribute<*>) as T? ?: getFilteredParentAttribute(key) as T?
 
-    override fun isEmpty(): Boolean = attributesMap.isEmpty() && (parent?.isEmpty ?: true)
+    override fun isEmpty(): Boolean = attributesMap.isEmpty() && (parent?.keySet().orEmpty().filter(filterParentAttributes).isEmpty())
 
-    override fun keySet(): Set<Attribute<*>> = attributesMap.keys + parent?.keySet().orEmpty()
+    override fun keySet(): Set<Attribute<*>> = attributesMap.keys + parent?.keySet().orEmpty().filter(filterParentAttributes)
 
     override fun <T : Any?> attribute(key: Attribute<T>?, value: T): AttributeContainer {
         val checkedValue = requireNotNull(value as Any?) { "null values for attributes are not supported" }

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

@@ -13,10 +13,7 @@ import org.gradle.api.capabilities.Capability
 import org.gradle.api.component.ComponentWithVariants
 import org.gradle.api.internal.component.SoftwareComponentInternal
 import org.gradle.api.internal.component.UsageContext
-import org.jetbrains.kotlin.gradle.plugin.KotlinCompilation
-import org.jetbrains.kotlin.gradle.plugin.KotlinCompilationToRunnableFiles
-import org.jetbrains.kotlin.gradle.plugin.KotlinTarget
-import org.jetbrains.kotlin.gradle.plugin.KotlinTargetComponent
+import org.jetbrains.kotlin.gradle.plugin.*
 import org.jetbrains.kotlin.utils.ifEmpty
 
 class KotlinSoftwareComponent(
@@ -72,7 +69,7 @@ internal class KotlinPlatformUsageContext(
         configuration.artifacts
 
     override fun getAttributes(): AttributeContainer =
-        configuration.outgoing.attributes
+        HierarchyAttributeContainer(configuration.outgoing.attributes) { it != ProjectLocalConfigurations.ATTRIBUTE }
 
     override fun getCapabilities(): Set<Capability> = emptySet()