[Gradle] Add user-specific attributes to host-specific metadata elements

KT-55751 Verification Pending
KT-56450 Verification Pending

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/KotlinMultiplatformPlugin.kt

@@ -244,6 +244,14 @@ internal fun applyUserDefinedAttributes(target: AbstractKotlinTarget) {
                 .mapNotNull { configurationName -> target.project.configurations.findByName(configurationName) }
                 .forEach { configuration -> copyAttributes(compilationAttributes, configuration.attributes) }
         }
+
+        // Copy to host-specific metadata elements configurations
+        if (target is KotlinNativeTarget) {
+            val hostSpecificMetadataElements = project.configurations.findByName(target.hostSpecificMetadataElementsConfigurationName)
+            if (hostSpecificMetadataElements != null) {
+                copyAttributes(from = target.attributes, to = hostSpecificMetadataElements.attributes)
+            }
+        }
     }
 }
 

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/targets/native/KotlinNativeTargetConfigurator.kt

@@ -31,6 +31,7 @@ import org.jetbrains.kotlin.gradle.plugin.internal.artifactTypeAttribute
 import org.jetbrains.kotlin.gradle.plugin.mpp.*
 import org.jetbrains.kotlin.gradle.plugin.mpp.apple.registerEmbedAndSignAppleFrameworkTask
 import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.GradleKpmVariant
+import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.util.copyAttributes
 import org.jetbrains.kotlin.gradle.plugin.sources.DefaultLanguageSettingsBuilder
 import org.jetbrains.kotlin.gradle.targets.metadata.isKotlinGranularMetadataEnabled
 import org.jetbrains.kotlin.gradle.targets.native.*
@@ -213,10 +214,7 @@ open class KotlinNativeTargetConfigurator<T : KotlinNativeTarget> : AbstractKotl
 
                 configuration.extendsFrom(*apiElements.extendsFrom.toTypedArray())
 
-                fun <T> copyAttribute(from: AttributeContainer, to: AttributeContainer, attribute: Attribute<T>) {
-                    to.attribute(attribute, from.getAttribute(attribute)!!)
-                }
-                with(apiElements.attributes) { keySet().forEach { copyAttribute(this, configuration.attributes, it) } }
+                copyAttributes(from = apiElements.attributes, to = configuration.attributes)
                 configuration.attributes.attribute(USAGE_ATTRIBUTE, objects.named(Usage::class.java, KotlinUsages.KOTLIN_METADATA))
             }
         }

libraries/tools/kotlin-gradle-plugin/src/functionalTest/kotlin/org/jetbrains/kotlin/gradle/regressionTests/ConfigurationsTest.kt

@@ -573,7 +573,8 @@ class ConfigurationsTest : MultiplatformExtensionTest() {
                     binaries.framework("main", listOf(NativeBuildType.DEBUG))
                 }
 
-                linuxX64()
+                linuxX64("linuxA") { attributes { attribute(distinguishingAttribute, "linuxA") } }
+                linuxX64("linuxB") { attributes { attribute(distinguishingAttribute, "linuxB") } }
 
                 targets.filterIsInstance<KotlinNativeTarget>().forEach {
                     it.binaries {