Type alias can't expand to 'dynamic'

compiler/frontend/src/org/jetbrains/kotlin/resolve/DeclarationsChecker.kt

@@ -31,10 +31,7 @@ import org.jetbrains.kotlin.resolve.BindingContext.TYPE
 import org.jetbrains.kotlin.resolve.BindingContext.TYPE_PARAMETER
 import org.jetbrains.kotlin.resolve.DescriptorUtils.classCanHaveAbstractMembers
 import org.jetbrains.kotlin.resolve.DescriptorUtils.classCanHaveOpenMembers
-import org.jetbrains.kotlin.types.IntersectionTypeConstructor
-import org.jetbrains.kotlin.types.KotlinType
-import org.jetbrains.kotlin.types.SubstitutionUtils
-import org.jetbrains.kotlin.types.TypeUtils
+import org.jetbrains.kotlin.types.*
 import org.jetbrains.kotlin.types.checker.KotlinTypeChecker
 import org.jetbrains.kotlin.types.typeUtil.contains
 import org.jetbrains.kotlin.types.typeUtil.isNothing
@@ -149,14 +146,14 @@ class DeclarationsChecker(
     }
 
     private fun checkTypeAliasDeclaration(typeAliasDescriptor: TypeAliasDescriptor, declaration: KtTypeAlias) {
-        val typeReference = declaration.getTypeReference()
-        if (typeReference == null) return
+        val typeReference = declaration.getTypeReference() ?: return
 
         val expandedType = typeAliasDescriptor.expandedType // TODO refactor type alias expansion
         if (expandedType.isError) return
 
         val expandedClassifier = expandedType.constructor.declarationDescriptor
-        if (expandedClassifier is TypeParameterDescriptor) {
+
+        if (expandedType.isDynamic() || expandedClassifier is TypeParameterDescriptor) {
             trace.report(TYPEALIAS_SHOULD_EXPAND_TO_CLASS.on(typeReference, expandedType))
         }
     }

compiler/frontend/src/org/jetbrains/kotlin/resolve/TypeAliasExpander.kt

@@ -138,7 +138,10 @@ class TypeAliasExpander(
 
                 val expandedType = expandRecursively(nestedExpansion, type.annotations, recursionDepth + 1, false)
 
-                return TypeProjectionImpl(originalProjection.projectionKind, expandedType.withAbbreviatedType(type))
+                // 'dynamic' type can't be abbreviated - will be reported separately
+                val typeWithAbbreviation = if (expandedType.isDynamic()) expandedType else expandedType.withAbbreviatedType(type)
+
+                return TypeProjectionImpl(originalProjection.projectionKind, typeWithAbbreviation)
             }
             else -> {
                 val substitutedArguments = type.arguments.mapIndexed { i, originalArgument ->

compiler/testData/diagnostics/testsWithJsStdLib/dynamicTypes/typealiasExpandingToDynamic.kt

@@ -0,0 +1,6 @@
+typealias Dyn = <!TYPEALIAS_SHOULD_EXPAND_TO_CLASS!>dynamic<!>
+typealias Dyn2 = <!TYPEALIAS_SHOULD_EXPAND_TO_CLASS!>Dyn<!>
+typealias Dyn3 = <!TYPEALIAS_SHOULD_EXPAND_TO_CLASS!>Dyn2<!>
+
+typealias Type<T> = <!TYPEALIAS_SHOULD_EXPAND_TO_CLASS!>T<!>
+typealias Dyn4 = <!TYPEALIAS_SHOULD_EXPAND_TO_CLASS!>Type<Dyn><!>

compiler/testData/diagnostics/testsWithJsStdLib/dynamicTypes/typealiasExpandingToDynamic.txt

@@ -0,0 +1,7 @@
+package
+
+public typealias Dyn = dynamic
+public typealias Dyn2 = Dyn
+public typealias Dyn3 = Dyn2
+public typealias Dyn4 = Type<Dyn>
+public typealias Type</*0*/ T>  = T

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestWithJsStdLibGenerated.java

@@ -235,6 +235,12 @@ public class DiagnosticsTestWithJsStdLibGenerated extends AbstractDiagnosticsTes
             doTest(fileName);
         }
 
+        @TestMetadata("typealiasExpandingToDynamic.kt")
+        public void testTypealiasExpandingToDynamic() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/testsWithJsStdLib/dynamicTypes/typealiasExpandingToDynamic.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("varargs.kt")
         public void testVarargs() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/testsWithJsStdLib/dynamicTypes/varargs.kt");