Provide quick fix for migration of single elements in named arguments

See more in KT-20171

idea/src/org/jetbrains/kotlin/idea/quickfix/QuickFixRegistrar.kt

@@ -518,5 +518,6 @@ class QuickFixRegistrar : QuickFixContributor {
         ANNOTATION_USED_AS_ANNOTATION_ARGUMENT.registerFactory(RemoveAtFromAnnotationArgument)
 
         ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_ANNOTATION.registerFactory(ReplaceWithArrayCallInAnnotationFix)
+        ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_FUNCTION.registerFactory(SurroundWithArrayOfWithSpreadOperatorInFunctionFix)
     }
 }

idea/src/org/jetbrains/kotlin/idea/quickfix/SurroundWithArrayOfWithSpreadOperatorInFunctionFix.kt

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2010-2017 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.idea.quickfix
+
+import com.intellij.openapi.editor.Editor
+import com.intellij.openapi.project.Project
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.diagnostics.Diagnostic
+import org.jetbrains.kotlin.diagnostics.Errors
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
+import org.jetbrains.kotlin.resolve.CollectionLiteralResolver.Companion.ARRAY_OF_FUNCTION
+import org.jetbrains.kotlin.resolve.CollectionLiteralResolver.Companion.PRIMITIVE_TYPE_TO_ARRAY
+
+class SurroundWithArrayOfWithSpreadOperatorInFunctionFix(
+        val wrapper: Name,
+        argument: KtExpression
+) : KotlinQuickFixAction<KtExpression>(argument) {
+    override fun getText() = "Surround with *$wrapper(...)"
+
+    override fun getFamilyName() = text
+
+    override fun invoke(project: Project, editor: Editor?, file: KtFile) {
+        val argument = element?.getParentOfType<KtValueArgument>(false) ?: return
+        val argumentName = argument.getArgumentName()?.asName ?: return
+        val argumentExpression = argument.getArgumentExpression() ?: return
+
+        val factory = KtPsiFactory(argumentExpression)
+
+        val surroundedWithArrayOf = factory.createExpressionByPattern("$wrapper($0)", argumentExpression)
+        val newArgument = factory.createArgument(surroundedWithArrayOf, argumentName, isSpread = true)
+
+        argument.replace(newArgument)
+    }
+
+    companion object : KotlinSingleIntentionActionFactory() {
+        override fun createAction(diagnostic: Diagnostic): KotlinQuickFixAction<KtExpression>? {
+            val actualDiagnostic = Errors.ASSIGNING_SINGLE_ELEMENT_TO_VARARG_IN_NAMED_FORM_FUNCTION.cast(diagnostic)
+            val parameterType = actualDiagnostic.a
+
+            val wrapper = PRIMITIVE_TYPE_TO_ARRAY[KotlinBuiltIns.getPrimitiveArrayElementType(parameterType)] ?: ARRAY_OF_FUNCTION
+            return SurroundWithArrayOfWithSpreadOperatorInFunctionFix(wrapper, actualDiagnostic.psiElement)
+        }
+    }
+}