[LC] add test on unit type actualization

^KT-65843

compiler/testData/asJava/lightClasses/lightClassByFqName/UnitAsTypeAlias.descriptors.java

@@ -0,0 +1,14 @@
+public final class Usage /* mypack.Usage*/ {
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit nullableUnitTypeAlias();//  nullableUnitTypeAlias()
+
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit nullableUnitTypeAliasAsNullable();//  nullableUnitTypeAliasAsNullable()
+
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit unitTypeAliasAsNullable();//  unitTypeAliasAsNullable()
+
+  public  Usage();//  .ctor()
+
+  public final void unitTypeAlias();//  unitTypeAlias()
+}

compiler/testData/asJava/lightClasses/lightClassByFqName/UnitAsTypeAlias.java

@@ -0,0 +1,15 @@
+public final class Usage /* mypack.Usage*/ {
+  @org.jetbrains.annotations.NotNull()
+  public final kotlin.Unit unitTypeAlias();//  unitTypeAlias()
+
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit nullableUnitTypeAlias();//  nullableUnitTypeAlias()
+
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit nullableUnitTypeAliasAsNullable();//  nullableUnitTypeAliasAsNullable()
+
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit unitTypeAliasAsNullable();//  unitTypeAliasAsNullable()
+
+  public  Usage();//  .ctor()
+}

compiler/testData/asJava/lightClasses/lightClassByFqName/UnitAsTypeAlias.kt

@@ -0,0 +1,16 @@
+// mypack.Usage
+package mypack
+
+typealias UnitTypeAlias = Unit
+typealias NullableUnitTypeAlias = Unit?
+
+class Usage {
+    fun unitTypeAlias(): UnitTypeAlias {
+
+    }
+
+    fun unitTypeAliasAsNullable(): UnitTypeAlias? = null
+
+    fun nullableUnitTypeAlias(): NullableUnitTypeAlias = null
+    fun nullableUnitTypeAliasAsNullable(): NullableUnitTypeAlias? = null
+}

compiler/testData/asJava/lightClasses/lightClassByFqName/UnitAsTypeAlias.lib.java

@@ -0,0 +1,14 @@
+public final class Usage /* mypack.Usage*/ {
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit nullableUnitTypeAlias();//  nullableUnitTypeAlias()
+
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit nullableUnitTypeAliasAsNullable();//  nullableUnitTypeAliasAsNullable()
+
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit unitTypeAliasAsNullable();//  unitTypeAliasAsNullable()
+
+  public  Usage();//  .ctor()
+
+  public final void unitTypeAlias();//  unitTypeAlias()
+}

compiler/testData/asJava/lightClasses/lightClassByFqName/compilationErrors/UnitAsTypeAliasActualization.descriptors.java

@@ -0,0 +1,16 @@
+public final class Usage /* mypack.Usage*/ {
+  @org.jetbrains.annotations.NotNull()
+  private final kotlin.Unit prop;
+
+  @org.jetbrains.annotations.NotNull()
+  public final kotlin.Unit getProp();//  getProp()
+
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit getNullableProperty();//  getNullableProperty()
+
+  public  Usage();//  .ctor()
+
+  public final void foo();//  foo()
+
+  public final void usage(@org.jetbrains.annotations.NotNull() kotlin.Unit);//  usage(kotlin.Unit)
+}

compiler/testData/asJava/lightClasses/lightClassByFqName/compilationErrors/UnitAsTypeAliasActualization.java

@@ -0,0 +1,17 @@
+public final class Usage /* mypack.Usage*/ {
+  @org.jetbrains.annotations.NotNull()
+  private final kotlin.Unit prop;
+
+  @org.jetbrains.annotations.NotNull()
+  public final kotlin.Unit foo();//  foo()
+
+  @org.jetbrains.annotations.NotNull()
+  public final kotlin.Unit getProp();//  getProp()
+
+  @org.jetbrains.annotations.Nullable()
+  public final kotlin.Unit getNullableProperty();//  getNullableProperty()
+
+  public  Usage();//  .ctor()
+
+  public final void usage(@org.jetbrains.annotations.NotNull() kotlin.Unit);//  usage(kotlin.Unit)
+}

compiler/testData/asJava/lightClasses/lightClassByFqName/compilationErrors/UnitAsTypeAliasActualization.kt

@@ -0,0 +1,26 @@
+// mypack.Usage
+// SKIP_IDE_TEST
+// MODULE: common
+// FILE: common.kt
+package mypack
+
+expect class MyPlatformSpecificClass
+
+// MODULE: main-jvm()()(common)
+// FILE: usage.kt
+package mypack
+
+actual typealias MyPlatformSpecificClass = Unit
+
+class Usage {
+    fun foo(): MyPlatformSpecificClass {
+
+    }
+
+    val prop: MyPlatformSpecificClass
+    val nullableProperty: MyPlatformSpecificClass? get() = null
+
+    fun usage(voidParam: MyPlatformSpecificClass) {
+
+    }
+}