Create INTERSECTION_TYPE stubs for definitely non-nullable types

^KTIJ-20802 Fixed

analysis/decompiled/decompiler-to-file-stubs/testData/clsFileStubBuilder/DefinitelyNotNullTypes/DefinitelyNotNullTypes.kt

@@ -0,0 +1,9 @@
+class DefinitelyNotNullTypes<T>(private val x: T & Any) {
+    fun foo(xs: List<T & Any>): T & Any {
+        return if (xs.isNotEmpty()) xs[0] else x
+    }
+
+    fun <R> bar(x: R & Any, action: (R & Any) -> R & Any): R & Any {
+        return action(x)
+    }
+}

analysis/decompiled/decompiler-to-file-stubs/testData/clsFileStubBuilder/DefinitelyNotNullTypes/DefinitelyNotNullTypes.txt

@@ -0,0 +1,102 @@
+PsiJetFileStubImpl[package=]
+  PACKAGE_DIRECTIVE
+  IMPORT_LIST
+  CLASS[classId=/DefinitelyNotNullTypes, fqName=DefinitelyNotNullTypes, isEnumEntry=false, isInterface=false, isLocal=false, isTopLevel=true, name=DefinitelyNotNullTypes, superNames=[]]
+    MODIFIER_LIST[public final]
+    TYPE_PARAMETER_LIST
+      TYPE_PARAMETER[fqName=null, isInVariance=false, isOutVariance=false, name=T]
+    PRIMARY_CONSTRUCTOR
+      MODIFIER_LIST[public]
+      VALUE_PARAMETER_LIST
+        VALUE_PARAMETER[fqName=null, hasDefaultValue=false, hasValOrVar=false, isMutable=false, name=x]
+          TYPE_REFERENCE
+            INTERSECTION_TYPE
+              TYPE_REFERENCE
+                USER_TYPE
+                  REFERENCE_EXPRESSION[referencedName=T]
+              TYPE_REFERENCE
+                USER_TYPE
+                  REFERENCE_EXPRESSION[referencedName=Any]
+    CLASS_BODY
+      PROPERTY[fqName=DefinitelyNotNullTypes.x, hasDelegate=false, hasDelegateExpression=false, hasInitializer=false, hasReturnTypeRef=true, isExtension=false, isTopLevel=false, isVar=false, name=x]
+        MODIFIER_LIST[private final]
+        TYPE_REFERENCE
+          INTERSECTION_TYPE
+            TYPE_REFERENCE
+              USER_TYPE
+                REFERENCE_EXPRESSION[referencedName=T]
+            TYPE_REFERENCE
+              USER_TYPE
+                REFERENCE_EXPRESSION[referencedName=Any]
+      FUN[fqName=DefinitelyNotNullTypes.bar, hasBlockBody=true, hasBody=true, hasTypeParameterListBeforeFunctionName=true, isExtension=false, isTopLevel=false, mayHaveContract=false, name=bar]
+        MODIFIER_LIST[public final]
+        TYPE_PARAMETER_LIST
+          TYPE_PARAMETER[fqName=null, isInVariance=false, isOutVariance=false, name=R]
+        VALUE_PARAMETER_LIST
+          VALUE_PARAMETER[fqName=null, hasDefaultValue=false, hasValOrVar=false, isMutable=false, name=x]
+            TYPE_REFERENCE
+              INTERSECTION_TYPE
+                TYPE_REFERENCE
+                  USER_TYPE
+                    REFERENCE_EXPRESSION[referencedName=R]
+                TYPE_REFERENCE
+                  USER_TYPE
+                    REFERENCE_EXPRESSION[referencedName=Any]
+          VALUE_PARAMETER[fqName=null, hasDefaultValue=false, hasValOrVar=false, isMutable=false, name=action]
+            TYPE_REFERENCE
+              FUNCTION_TYPE
+                VALUE_PARAMETER_LIST
+                  VALUE_PARAMETER[fqName=null, hasDefaultValue=false, hasValOrVar=false, isMutable=false, name=null]
+                    TYPE_REFERENCE
+                      INTERSECTION_TYPE
+                        TYPE_REFERENCE
+                          USER_TYPE
+                            REFERENCE_EXPRESSION[referencedName=R]
+                        TYPE_REFERENCE
+                          USER_TYPE
+                            REFERENCE_EXPRESSION[referencedName=Any]
+                TYPE_REFERENCE
+                  INTERSECTION_TYPE
+                    TYPE_REFERENCE
+                      USER_TYPE
+                        REFERENCE_EXPRESSION[referencedName=R]
+                    TYPE_REFERENCE
+                      USER_TYPE
+                        REFERENCE_EXPRESSION[referencedName=Any]
+        TYPE_REFERENCE
+          INTERSECTION_TYPE
+            TYPE_REFERENCE
+              USER_TYPE
+                REFERENCE_EXPRESSION[referencedName=R]
+            TYPE_REFERENCE
+              USER_TYPE
+                REFERENCE_EXPRESSION[referencedName=Any]
+      FUN[fqName=DefinitelyNotNullTypes.foo, hasBlockBody=true, hasBody=true, hasTypeParameterListBeforeFunctionName=false, isExtension=false, isTopLevel=false, mayHaveContract=false, name=foo]
+        MODIFIER_LIST[public final]
+        VALUE_PARAMETER_LIST
+          VALUE_PARAMETER[fqName=null, hasDefaultValue=false, hasValOrVar=false, isMutable=false, name=xs]
+            TYPE_REFERENCE
+              USER_TYPE
+                USER_TYPE
+                  USER_TYPE
+                    REFERENCE_EXPRESSION[referencedName=kotlin]
+                  REFERENCE_EXPRESSION[referencedName=collections]
+                REFERENCE_EXPRESSION[referencedName=List]
+                TYPE_ARGUMENT_LIST
+                  TYPE_PROJECTION[projectionKind=NONE]
+                    TYPE_REFERENCE
+                      INTERSECTION_TYPE
+                        TYPE_REFERENCE
+                          USER_TYPE
+                            REFERENCE_EXPRESSION[referencedName=T]
+                        TYPE_REFERENCE
+                          USER_TYPE
+                            REFERENCE_EXPRESSION[referencedName=Any]
+        TYPE_REFERENCE
+          INTERSECTION_TYPE
+            TYPE_REFERENCE
+              USER_TYPE
+                REFERENCE_EXPRESSION[referencedName=T]
+            TYPE_REFERENCE
+              USER_TYPE
+                REFERENCE_EXPRESSION[referencedName=Any]

analysis/decompiled/decompiler-to-file-stubs/tests/org/jetbrains/kotlin/analysis/decompiler/stub/files/ClsStubBuilderTestGenerated.java

@@ -108,6 +108,12 @@ public class ClsStubBuilderTestGenerated extends AbstractClsStubBuilderTest {
         runTest("analysis/decompiled/decompiler-to-file-stubs/testData/clsFileStubBuilder/DataClass/");
     }
 
+    @Test
+    @TestMetadata("DefinitelyNotNullTypes")
+    public void testDefinitelyNotNullTypes() throws Exception {
+        runTest("analysis/decompiled/decompiler-to-file-stubs/testData/clsFileStubBuilder/DefinitelyNotNullTypes/");
+    }
+
     @Test
     @TestMetadata("Delegation")
     public void testDelegation() throws Exception {

analysis/decompiled/decompiler-to-stubs/src/org/jetbrains/kotlin/analysis/decompiler/stub/TypeClsStubBuilder.kt

@@ -70,8 +70,21 @@ class TypeClsStubBuilder(private val c: ClsStubBuilderContext) {
 
     private fun createTypeParameterStub(parent: KotlinStubBaseImpl<*>, type: Type, name: Name, annotations: List<ClassIdWithTarget>) {
         createTypeAnnotationStubs(parent, type, annotations)
-        val nullableParentWrapper = nullableTypeParent(parent, type)
+        if (Flags.DEFINITELY_NOT_NULL_TYPE.get(type.flags)) {
-        createStubForTypeName(ClassId.topLevel(FqName.topLevel(name)), nullableParentWrapper)
+            createDefinitelyNotNullTypeStub(parent, FqName.topLevel(name))
+        } else {
+            val nullableParentWrapper = nullableTypeParent(parent, type)
+            createStubForTypeName(ClassId.topLevel(FqName.topLevel(name)), nullableParentWrapper)
+        }
+    }
+
+    private fun createDefinitelyNotNullTypeStub(parent: KotlinStubBaseImpl<*>, name: FqName) {
+        val intersectionType = KotlinPlaceHolderStubImpl<KtIntersectionType>(parent, KtStubElementTypes.INTERSECTION_TYPE)
+        val leftReference = KotlinPlaceHolderStubImpl<KtTypeReference>(intersectionType, KtStubElementTypes.TYPE_REFERENCE)
+        createStubForTypeName(ClassId.topLevel(name), leftReference)
+        val rightReference = KotlinPlaceHolderStubImpl<KtTypeReference>(intersectionType, KtStubElementTypes.TYPE_REFERENCE)
+        val userType = KotlinUserTypeStubImpl(rightReference)
+        KotlinNameReferenceExpressionStubImpl(userType, StandardNames.FqNames.any.shortName().ref())
     }
 
     private fun createClassReferenceTypeStub(parent: KotlinStubBaseImpl<*>, type: Type, annotations: List<ClassIdWithTarget>) {