Allow use expression of array type as named argument for vararg

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -716,6 +716,7 @@ public interface Errors {
 
     DiagnosticFactory1<KtExpression, KotlinType> ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_FUNCTION = DiagnosticFactory1.create(WARNING);
     DiagnosticFactory1<KtExpression, KotlinType> ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_FUNCTION_ERROR = DiagnosticFactory1.create(ERROR);
+    DiagnosticFactory0<KtExpression> REDUNDANT_SPREAD_OPERATOR_IN_NAMED_FORM_IN_FUNCTION = DiagnosticFactory0.create(WARNING);
     DiagnosticFactory0<KtExpression> ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_ANNOTATION = DiagnosticFactory0.create(WARNING);
     DiagnosticFactory0<KtExpression> ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_ANNOTATION_ERROR = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<KtExpression> REDUNDANT_SPREAD_OPERATOR_IN_NAMED_FORM_IN_ANNOTATION = DiagnosticFactory0.create(WARNING);

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/DefaultErrorMessages.java

@@ -842,6 +842,7 @@ public class DefaultErrorMessages {
         MAP.put(NO_RECEIVER_ALLOWED, "No receiver can be passed to this function or property");
         MAP.put(ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_FUNCTION, "Assigning single elements to varargs in named form is deprecated", TO_STRING);
         MAP.put(ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_FUNCTION_ERROR, "Assigning single elements to varargs in named form is forbidden", TO_STRING);
+        MAP.put(REDUNDANT_SPREAD_OPERATOR_IN_NAMED_FORM_IN_FUNCTION, "Redundant spread (*) operator");
         MAP.put(ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_ANNOTATION, "Assigning single elements to varargs in named form is deprecated");
         MAP.put(ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_ANNOTATION_ERROR, "Assigning single elements to varargs in named form is forbidden");
         MAP.put(REDUNDANT_SPREAD_OPERATOR_IN_NAMED_FORM_IN_ANNOTATION, "Redundant spread (*) operator");

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallResolverUtil.kt

@@ -215,7 +215,10 @@ fun getEffectiveExpectedTypeForSingleArgument(
         return if (parameterDescriptor.varargElementType == null) DONT_CARE else parameterDescriptor.type
     }
 
-    if (arrayAssignmentToVarargInNamedFormInAnnotation(parameterDescriptor, argument, languageVersionSettings, trace)) {
+    if (
+        arrayAssignmentToVarargInNamedFormInAnnotation(parameterDescriptor, argument, languageVersionSettings, trace) ||
+        arrayAssignmentToVarargInNamedFormInFunction(parameterDescriptor, argument, languageVersionSettings, trace)
+    ) {
         return parameterDescriptor.type
     }
 
@@ -239,6 +242,17 @@ private fun arrayAssignmentToVarargInNamedFormInAnnotation(
     return argument.isNamed() && parameterDescriptor.isVararg && isArrayOrArrayLiteral(argument, trace)
 }
 
+private fun arrayAssignmentToVarargInNamedFormInFunction(
+    parameterDescriptor: ValueParameterDescriptor,
+    argument: ValueArgument,
+    languageVersionSettings: LanguageVersionSettings,
+    trace: BindingTrace
+): Boolean {
+    if (!languageVersionSettings.supportsFeature(LanguageFeature.AllowAssigningArrayElementsToVarargsInNamedFormForFunctions)) return false
+
+    return argument.isNamed() && parameterDescriptor.isVararg && isArrayOrArrayLiteral(argument, trace)
+}
+
 fun isArrayOrArrayLiteral(argument: ValueArgument, trace: BindingTrace): Boolean {
     val argumentExpression = argument.getArgumentExpression() ?: return false
     if (argumentExpression is KtCollectionLiteralExpression) return true

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/AssigningNamedArgumentToVarargChecker.kt

@@ -6,8 +6,7 @@
 package org.jetbrains.kotlin.resolve.calls.checkers
 
 import com.intellij.psi.PsiElement
-import org.jetbrains.kotlin.config.LanguageFeature.AssigningArraysToVarargsInNamedFormInAnnotations
-import org.jetbrains.kotlin.config.LanguageFeature.ProhibitAssigningSingleElementsToVarargsInNamedForm
+import org.jetbrains.kotlin.config.LanguageFeature.*
 import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 import org.jetbrains.kotlin.diagnostics.DiagnosticFactory
 import org.jetbrains.kotlin.diagnostics.Errors
@@ -84,9 +83,18 @@ class AssigningNamedArgumentToVarargChecker : CallChecker {
         context: ResolutionContext<*>,
         parameterDescriptor: ValueParameterDescriptor
     ) {
-        if (!argument.hasSpread()) {
-            reportMigrationDiagnostic(migrationDiagnosticsForFunction, context) { diagnostic ->
-                context.trace.report(diagnostic.on(argumentExpression, parameterDescriptor.type))
+        if (
+            context.languageVersionSettings.supportsFeature(AllowAssigningArrayElementsToVarargsInNamedFormForFunctions)
+            && isArrayOrArrayLiteral(argument, context.trace)
+        ) {
+            if (argument.hasSpread()) {
+                context.trace.report(Errors.REDUNDANT_SPREAD_OPERATOR_IN_NAMED_FORM_IN_FUNCTION.on(argumentExpression))
+            }
+        } else {
+            if (!argument.hasSpread()) {
+                reportMigrationDiagnostic(migrationDiagnosticsForFunction, context) { diagnostic ->
+                    context.trace.report(diagnostic.on(argumentExpression, parameterDescriptor.type))
+                }
             }
         }
     }
@@ -107,4 +115,7 @@ class AssigningNamedArgumentToVarargChecker : CallChecker {
     }
 }
 
-private data class MigrationDiagnostics<T : DiagnosticFactory<*>>(val warning: T, val error: T)
+private data class MigrationDiagnostics<T : DiagnosticFactory<*>>(val warning: T, val error: T)
+
+private val ResolutionContext<*>.isAssigningArrayEnabled: Boolean
+    get() = languageVersionSettings.supportsFeature(AllowAssigningArrayElementsToVarargsInNamedFormForFunctions)