Add serialization/deserialization of definitely-not-null types

^KT-26245 In Progress

compiler/fir/analysis-tests/testData/loadCompiledKotlin/annotations/types/DefinitelyNotNull.txt

@@ -0,0 +1 @@
+public final fun <T> foo(x: R|T!!|, y: R|kotlin/collections/List<T!!>|, z: R|(T!!) -> T!!|): R|T!!|

compiler/fir/fir-deserialization/src/org/jetbrains/kotlin/fir/deserialization/FirTypeDeserializer.kt

@@ -132,9 +132,16 @@ class FirTypeDeserializer(
     fun FirClassLikeSymbol<*>.typeParameters(): List<FirTypeParameterSymbol> =
         (fir as? FirTypeParameterRefsOwner)?.typeParameters?.map { it.symbol }.orEmpty()
 
-    fun simpleType(proto: ProtoBuf.Type, attributes: ConeAttributes): ConeLookupTagBasedType? {
+    fun simpleType(proto: ProtoBuf.Type, attributes: ConeAttributes): ConeSimpleKotlinType? {
         val constructor = typeSymbol(proto) ?: return null
-        if (constructor is ConeTypeParameterLookupTag) return ConeTypeParameterTypeImpl(constructor, isNullable = proto.nullable)
+        if (constructor is ConeTypeParameterLookupTag) {
+            return ConeTypeParameterTypeImpl(constructor, isNullable = proto.nullable).let {
+                if (Flags.DEFINITELY_NOT_NULL_TYPE.get(proto.flags))
+                    ConeDefinitelyNotNullType.create(it)
+                else
+                    it
+            }
+        }
         if (constructor !is ConeClassLikeLookupTag) return null
 
         fun ProtoBuf.Type.collectAllArguments(): List<ProtoBuf.Type.Argument> =

compiler/fir/fir-serialization/src/org/jetbrains/kotlin/fir/serialization/FirElementSerializer.kt

@@ -598,10 +598,16 @@ class FirElementSerializer private constructor(
         }
     }
 
-    private fun typeProto(type: ConeKotlinType, toSuper: Boolean = false, correspondingTypeRef: FirTypeRef? = null): ProtoBuf.Type.Builder {
+    private fun typeProto(
+        type: ConeKotlinType,
+        toSuper: Boolean = false,
+        correspondingTypeRef: FirTypeRef? = null,
+        isDefinitelyNotNullType: Boolean = false,
+    ): ProtoBuf.Type.Builder {
         val builder = ProtoBuf.Type.newBuilder()
 
         when (type) {
+            is ConeDefinitelyNotNullType -> return typeProto(type, toSuper, correspondingTypeRef, isDefinitelyNotNullType = true)
             is ConeKotlinErrorType -> {
                 extension.serializeErrorType(type, builder)
                 return builder
@@ -623,7 +629,7 @@ class FirElementSerializer private constructor(
                         session, CONTINUATION_INTERFACE_CLASS_ID
                     )
                     val functionType = typeProto(runtimeFunctionType)
-                    functionType.flags = Flags.getTypeFlags(true)
+                    functionType.flags = Flags.getTypeFlags(true, false)
                     return functionType
                 }
                 fillFromPossiblyInnerType(builder, type)
@@ -640,8 +646,11 @@ class FirElementSerializer private constructor(
                 } else {
                     builder.typeParameter = getTypeParameterId(typeParameter)
                 }
+
+                if (isDefinitelyNotNullType) {
+                    builder.flags = Flags.getTypeFlags(false, isDefinitelyNotNullType)
+                }
             }
-            is ConeDefinitelyNotNullType,
             is ConeIntersectionType -> {
                 val approximatedType = if (toSuper) {
                     typeApproximator.approximateToSuperType(type, TypeApproximatorConfiguration.PublicDeclaration)

compiler/serialization/src/org/jetbrains/kotlin/serialization/DescriptorSerializer.kt

@@ -584,7 +584,7 @@ class DescriptorSerializer private constructor(
 
         if (type.isSuspendFunctionType) {
             val functionType = type(transformSuspendFunctionToRuntimeFunctionType(type, extension.releaseCoroutines()))
-            functionType.flags = Flags.getTypeFlags(true)
+            functionType.flags = Flags.getTypeFlags(true, false)
             return functionType
         }
 
@@ -600,6 +600,8 @@ class DescriptorSerializer private constructor(
                     builder.typeParameter = getTypeParameterId(descriptor)
                 }
 
+                builder.flags = Flags.getTypeFlags(false, type is DefinitelyNotNullType)
+
                 assert(type.arguments.isEmpty()) { "Found arguments for type constructor build on type parameter: $descriptor" }
             }
         }

compiler/testData/loadJava/compiledKotlin/annotations/types/DefinitelyNotNull.kt

@@ -0,0 +1,5 @@
+// !LANGUAGE: +DefinitelyNotNullTypeParameters
+// COMPILER_ARGUMENTS: -XXLanguage:+DefinitelyNotNullTypeParameters
+package test
+
+fun <T> foo(x: T!!, y: List<T!!>, z: (T!!) -> T!!): T!! = x

compiler/testData/loadJava/compiledKotlin/annotations/types/DefinitelyNotNull.txt

@@ -0,0 +1,3 @@
+package test
+
+public fun </*0*/ T> foo(/*0*/ x: T!!, /*1*/ y: kotlin.collections.List<T!!>, /*2*/ z: (T!!) -> T!!): T!!

compiler/tests-gen/org/jetbrains/kotlin/jvm/compiler/LoadJavaTestGenerated.java

@@ -2116,6 +2116,11 @@ public class LoadJavaTestGenerated extends AbstractLoadJavaTest {
                     runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/ClassLiteralArgument.kt");
                 }
 
+                @TestMetadata("DefinitelyNotNull.kt")
+                public void testDefinitelyNotNull() throws Exception {
+                    runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/DefinitelyNotNull.kt");
+                }
+
                 @TestMetadata("ReceiverParameter.kt")
                 public void testReceiverParameter() throws Exception {
                     runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/ReceiverParameter.kt");

compiler/tests-gen/org/jetbrains/kotlin/jvm/compiler/LoadKotlinWithTypeTableTestGenerated.java

@@ -438,6 +438,11 @@ public class LoadKotlinWithTypeTableTestGenerated extends AbstractLoadKotlinWith
                 runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/ClassLiteralArgument.kt");
             }
 
+            @TestMetadata("DefinitelyNotNull.kt")
+            public void testDefinitelyNotNull() throws Exception {
+                runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/DefinitelyNotNull.kt");
+            }
+
             @TestMetadata("ReceiverParameter.kt")
             public void testReceiverParameter() throws Exception {
                 runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/ReceiverParameter.kt");

compiler/tests-gen/org/jetbrains/kotlin/jvm/compiler/ir/IrLoadJavaTestGenerated.java

@@ -2117,6 +2117,11 @@ public class IrLoadJavaTestGenerated extends AbstractIrLoadJavaTest {
                     runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/ClassLiteralArgument.kt");
                 }
 
+                @TestMetadata("DefinitelyNotNull.kt")
+                public void testDefinitelyNotNull() throws Exception {
+                    runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/DefinitelyNotNull.kt");
+                }
+
                 @TestMetadata("ReceiverParameter.kt")
                 public void testReceiverParameter() throws Exception {
                     runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/ReceiverParameter.kt");

compiler/tests-gen/org/jetbrains/kotlin/jvm/compiler/javac/LoadJavaUsingJavacTestGenerated.java

@@ -2116,6 +2116,11 @@ public class LoadJavaUsingJavacTestGenerated extends AbstractLoadJavaUsingJavacT
                     runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/ClassLiteralArgument.kt");
                 }
 
+                @TestMetadata("DefinitelyNotNull.kt")
+                public void testDefinitelyNotNull() throws Exception {
+                    runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/DefinitelyNotNull.kt");
+                }
+
                 @TestMetadata("ReceiverParameter.kt")
                 public void testReceiverParameter() throws Exception {
                     runTest("compiler/testData/loadJava/compiledKotlin/annotations/types/ReceiverParameter.kt");