[Gradle] Implement KotlinNativeCompileArgumentsTest for KT-57944

... covering K2 shared native compilations + sources
... covering K2 platform compilations + sources

libraries/tools/kotlin-gradle-plugin/src/functionalTest/kotlin/org/jetbrains/kotlin/gradle/unitTests/compilerArgumetns/KotlinNativeCompileArgumentsTest.kt

@@ -10,16 +10,17 @@ package org.jetbrains.kotlin.gradle.unitTests.compilerArgumetns
 import org.jetbrains.kotlin.cli.common.arguments.K2NativeCompilerArguments
 import org.jetbrains.kotlin.cli.common.arguments.parseCommandLineArguments
 import org.jetbrains.kotlin.compilerRunner.ArgumentUtils
+import org.jetbrains.kotlin.config.LanguageVersion
+import org.jetbrains.kotlin.gradle.dsl.KotlinVersion
 import org.jetbrains.kotlin.gradle.dsl.multiplatformExtension
+import org.jetbrains.kotlin.gradle.idea.tcs.extras.sourcesClasspathKey
 import org.jetbrains.kotlin.gradle.plugin.KotlinCompilerArgumentsProducer.CreateCompilerArgumentsContext.Companion.default
 import org.jetbrains.kotlin.gradle.plugin.KotlinCompilerArgumentsProducer.CreateCompilerArgumentsContext.Companion.lenient
 import org.jetbrains.kotlin.gradle.tasks.KotlinNativeCompile
 import org.jetbrains.kotlin.gradle.util.buildProjectWithMPP
 import org.jetbrains.kotlin.gradle.util.main
-import kotlin.test.Test
+import java.io.File
-import kotlin.test.assertEquals
+import kotlin.test.*
-import kotlin.test.assertFails
-import kotlin.test.assertNull
 
 class KotlinNativeCompileArgumentsTest {
     @Test
@@ -94,4 +95,114 @@ class KotlinNativeCompileArgumentsTest {
             listOf("my.OptIn", "my.other.OptIn"), arguments.optIn?.toList()
         )
     }
+
+    @Test
+    fun `test - k2 - shared native compilation - sources`() {
+        val project = buildProjectWithMPP()
+        val kotlin = project.multiplatformExtension
+        kotlin.linuxX64()
+        kotlin.linuxArm64()
+
+        /* Enable K2 if necessary */
+        if (KotlinVersion.DEFAULT < KotlinVersion.KOTLIN_2_0) {
+            kotlin.sourceSets.all {
+                it.languageSettings.languageVersion = "2.0"
+            }
+        }
+
+        val commonMainSourceFile = project.file("src/commonMain/kotlin/CommonMain.kt")
+        commonMainSourceFile.parentFile.mkdirs()
+        commonMainSourceFile.writeText("object CommonMain")
+
+        project.evaluate()
+
+        val sharedNativeCompilation = kotlin.metadata().compilations.getByName("commonMain")
+        val sharedNativeCompileTask = sharedNativeCompilation.compileTaskProvider.get() as KotlinNativeCompile
+        val arguments = sharedNativeCompileTask.createCompilerArguments(lenient)
+
+        assertTrue(
+            LanguageVersion.fromVersionString(arguments.languageVersion)!! >= LanguageVersion.KOTLIN_2_0,
+            "Expected 'languageVersion' 2.0 or higher"
+        )
+
+        assertNull(
+            arguments.fragments?.toList(),
+            "Expected 'fragments' to *not* be set: Metadata compilations shall use -Xcommon-sources and provide klib dependencies"
+        )
+
+        assertNull(
+            arguments.fragmentSources?.toList(),
+            "Expected 'fragmentSources' to *not* be set: Metadata compilations shall use -Xcommon-sources and provide klib dependencies"
+        )
+
+        assertNull(
+            arguments.fragmentRefines?.toList(),
+            "Expected 'fragmentRefines' to *not* be set: Metadata compilations shall use -Xcommon-sources and provide klib dependencies"
+        )
+
+        assertEquals(
+            listOf(commonMainSourceFile), arguments.commonSources?.toList().orEmpty().map(::File)
+        )
+
+        assertTrue(
+            commonMainSourceFile.absolutePath in arguments.freeArgs,
+            "Expected commonMain source file to be present in 'freeArgs'"
+        )
+    }
+
+    @Test
+    fun `test - k2 - platform native compilation - sources`() {
+        val project = buildProjectWithMPP()
+        val kotlin = project.multiplatformExtension
+        kotlin.linuxX64()
+
+        /* Enable K2 if necessary */
+        if (KotlinVersion.DEFAULT < KotlinVersion.KOTLIN_2_0) {
+            kotlin.sourceSets.all {
+                it.languageSettings.languageVersion = "2.0"
+            }
+        }
+
+        val linuxX64SourceFile = project.file("src/linuxX64Main/kotlin/CommonMain.kt")
+        linuxX64SourceFile.parentFile.mkdirs()
+        linuxX64SourceFile.writeText("object Linux")
+
+        project.evaluate()
+
+        val nativeCompilation = kotlin.linuxX64().compilations.main
+        val sharedNativeCompileTask = nativeCompilation.compileTaskProvider.get() as KotlinNativeCompile
+        val arguments = sharedNativeCompileTask.createCompilerArguments(lenient)
+
+        assertTrue(
+            LanguageVersion.fromVersionString(arguments.languageVersion)!! >= LanguageVersion.KOTLIN_2_0,
+            "Expected 'languageVersion' 2.0 or higher"
+        )
+
+        assertNull(
+            arguments.commonSources?.toList(),
+            "Expected 'commonSources' to not be set: Native Platform compilations shall use -Xfragment{x} arguments"
+        )
+
+        assertEquals(
+            setOf("commonMain", "linuxX64Main"),
+            arguments.fragments?.toSet(),
+            "Expected 'fragments' to *not* be set: Metadata compilations shall use -Xcommon-sources and provide klib dependencies"
+        )
+
+        assertEquals(
+            listOf("linuxX64Main:${linuxX64SourceFile.absolutePath}"),
+            arguments.fragmentSources?.toList(),
+        )
+
+        assertEquals(
+            listOf("linuxX64Main:commonMain"),
+            arguments.fragmentRefines?.toList(),
+        )
+
+
+        assertTrue(
+            linuxX64SourceFile.absolutePath in arguments.freeArgs,
+            "Expected linuxX64 source file to be present in 'freeArgs'"
+        )
+    }
 }