Fix falsely skipped shared-native source sets in HMPP (KT-38746)

Issue #KT-38746 Fixed

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

@@ -224,4 +224,28 @@ class KlibBasedMppIT : BaseGradleIT() {
             assertSuccessful()
         }
     }
+
+    @Test
+    fun testAvoidSkippingSharedNativeSourceSetKt38746() = with(Project("hierarchical-all-native")) {
+        val targetNames = listOf(
+            // Try different alphabetical ordering of the targets to ensure that the behavior doesn't depend on it, as with 'first target'
+            listOf("a1", "a2", "a3"),
+            listOf("a3", "a1", "a2"),
+            listOf("a2", "a3", "a1"),
+        )
+        val targetParamNames = listOf("mingwTargetName", "linuxTargetName", "macosTargetName", "currentHostTargetName")
+        for (names in targetNames) {
+            val currentHostTargetName = when {
+                HostManager.hostIsMingw -> names[0]
+                HostManager.hostIsLinux -> names[1]
+                HostManager.hostIsMac -> names[2]
+                else -> error("unexpected host")
+            }
+            val params = targetParamNames.zip(names + currentHostTargetName) { k, v -> "-P$k=$v" }
+            build(":clean", ":compileCurrentHostAndLinuxKotlinMetadata", *params.toTypedArray()) {
+                assertSuccessful()
+                assertTasksExecuted(":compileCurrentHostAndLinuxKotlinMetadata", ":compileAllNativeKotlinMetadata")
+            }
+        }
+    }
 }

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

@@ -0,0 +1,37 @@
+plugins {
+    kotlin("multiplatform")
+}
+
+repositories {
+    mavenLocal()
+    jcenter()
+}
+
+kotlin {
+	val mingwTargetName: String by project
+	val linuxTargetName: String by project
+	val macosTargetName: String by project
+	val currentHostTargetName: String by project
+
+    val mingw = mingwX64(mingwTargetName) { }
+    val linux = linuxX64(linuxTargetName) { }
+    val macos = macosX64(macosTargetName) { }
+    val linuxArm = linuxArm64()
+
+	sourceSets {
+		val allNative by creating {
+			dependsOn(getByName("commonMain"))
+			listOf(mingw, linux, macos).forEach {
+				it.compilations["main"].defaultSourceSet.dependsOn(this@creating)
+			}
+		}
+
+    	val currentHostAndLinux by creating {
+    		dependsOn(allNative)
+    	}
+
+    	configure(listOf(linuxArm, targets.getByName(currentHostTargetName))) {
+			compilations["main"].defaultSourceSet.dependsOn(currentHostAndLinux)
+    	}
+    }
+}

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/hierarchical-all-native/gradle.properties

@@ -0,0 +1 @@
+kotlin.mpp.enableGranularSourceSetsMetadata=true

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

@@ -0,0 +1,12 @@
+pluginManagement {
+    repositories {
+        mavenLocal()
+        gradlePluginPortal()
+    }
+    val kotlin_version: String by settings
+    plugins {
+    	kotlin("multiplatform").version(kotlin_version)
+    }
+}
+
+rootProject.name = "my-lib-foo"

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/hierarchical-all-native/src/allNative/kotlin/Foo.kt

@@ -0,0 +1,10 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package com.example.foo
+
+expect fun foo(): String
+
+fun fooCommon() = "foo"

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/hierarchical-all-native/src/currentHostAndLinux/kotlin/UseFoo.kt

@@ -0,0 +1,10 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package com.example.foo
+
+actual fun foo(): String = "foo"
+
+fun useFooCommon() = fooCommon()

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/native/KotlinNativeCompilation.kt

@@ -102,7 +102,8 @@ class KotlinSharedNativeCompilation(override val target: KotlinMetadataTarget, v
         target,
         // TODO: this will end up as '-target' argument passed to K2Native, which is wrong.
         // Rewrite this when we'll compile native-shared source-sets against commonized platform libs
-        konanTargets.first(),
+        // We find any konan target that is enabled on the current host in order to pass the checks that avoid compiling the code otherwise.
+        konanTargets.find { it.enabledOnCurrentHost } ?: konanTargets.first(),
         name
     ),
     KotlinMetadataCompilation<KotlinCommonOptions> {