diff --git a/compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/CliArgumentStringBuilder.kt b/compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/CliArgumentStringBuilder.kt
index 6fff47ae6f4..f9688221ee1 100644
--- a/compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/CliArgumentStringBuilder.kt
+++ b/compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/CliArgumentStringBuilder.kt
@@ -8,7 +8,7 @@ package org.jetbrains.kotlin.cli.common.arguments
 import org.jetbrains.kotlin.config.LanguageFeature
 
 object CliArgumentStringBuilder {
-    const val languagePrefix = "-XXLanguage:"
+    private const val languagePrefix = "-XXLanguage:"
 
     private val LanguageFeature.State.sign: String
         get() = when (this) {
@@ -21,4 +21,30 @@ object CliArgumentStringBuilder {
     fun LanguageFeature.buildArgumentString(state: LanguageFeature.State): String {
         return "$languagePrefix${state.sign}$name"
     }
+
+    fun String.replaceLanguageFeature(
+        feature: LanguageFeature,
+        state: LanguageFeature.State,
+        prefix: String = "",
+        postfix: String = "",
+        separator: String = ", ",
+        quoted: Boolean = true
+    ): String {
+        val existingFeatureIndex = indexOf(feature.name)
+        val languagePrefixIndex = lastIndexOf(languagePrefix, existingFeatureIndex)
+        val featureArgumentString = feature.buildArgumentString(state)
+        val quote = if (quoted) "\"" else ""
+        return if (languagePrefixIndex != -1) {
+            replaceRange(languagePrefixIndex, existingFeatureIndex + feature.name.length, featureArgumentString)
+        } else {
+            val splitText = if (postfix.isNotEmpty()) split(postfix) else listOf(this, "")
+            if (splitText.size != 2) {
+                "$prefix$quote$featureArgumentString$quote$postfix"
+            } else {
+                val (mainPart, commentPart) = splitText
+                // In Groovy / Kotlin DSL, we can have comment after [...] or listOf(...)
+                mainPart + "$separator$quote$featureArgumentString$quote$postfix" + commentPart
+            }
+        }
+    }
 }
\ No newline at end of file
diff --git a/idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/GroovyBuildScriptManipulator.kt b/idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/GroovyBuildScriptManipulator.kt
index e5151466863..2ae609d28a8 100644
--- a/idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/GroovyBuildScriptManipulator.kt
+++ b/idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/GroovyBuildScriptManipulator.kt
@@ -22,7 +22,7 @@ import com.intellij.openapi.util.text.StringUtil
 import com.intellij.psi.PsiElement
 import com.intellij.psi.codeStyle.CodeStyleManager
 import org.jetbrains.kotlin.cli.common.arguments.CliArgumentStringBuilder.buildArgumentString
-import org.jetbrains.kotlin.cli.common.arguments.CliArgumentStringBuilder.languagePrefix
+import org.jetbrains.kotlin.cli.common.arguments.CliArgumentStringBuilder.replaceLanguageFeature
 import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.idea.configuration.KotlinWithGradleConfigurator.Companion.getBuildScriptSettingsPsiFile
 import org.jetbrains.kotlin.idea.util.application.runReadAction
@@ -166,19 +166,8 @@ class GroovyBuildScriptManipulator(
             "[\"$featureArgumentString\"]",
             forTests
         ) { insideKotlinOptions ->
-            val existingFeatureIndex = text.indexOf(feature.name)
-            val languagePrefixIndex = text.lastIndexOf(languagePrefix, existingFeatureIndex)
-            val newText = if (languagePrefixIndex != -1) {
-                text.substring(0, languagePrefixIndex) + featureArgumentString + text.substring(existingFeatureIndex + feature.name.length)
-            } else {
-                val splitText = text.split("]")
-                if (splitText.size != 2) {
-                    val prefix = if (insideKotlinOptions) "kotlinOptions." else ""
-                    "$prefix$parameterName = [\"$featureArgumentString\"]"
-                } else {
-                    splitText[0] + ", \"$featureArgumentString\"]" + splitText[1]
-                }
-            }
+            val prefix = if (insideKotlinOptions) "kotlinOptions." else ""
+            val newText = text.replaceLanguageFeature(feature, state, prefix = "$prefix$parameterName = [", postfix = "]")
             replaceWithStatementFromText(newText)
         }
     }
diff --git a/idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/KotlinBuildScriptManipulator.kt b/idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/KotlinBuildScriptManipulator.kt
index fbf44b4e60b..424fbfd9a3f 100644
--- a/idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/KotlinBuildScriptManipulator.kt
+++ b/idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/KotlinBuildScriptManipulator.kt
@@ -22,7 +22,7 @@ import com.intellij.openapi.util.text.StringUtil
 import com.intellij.psi.PsiElement
 import com.intellij.psi.util.PsiTreeUtil
 import org.jetbrains.kotlin.cli.common.arguments.CliArgumentStringBuilder.buildArgumentString
-import org.jetbrains.kotlin.cli.common.arguments.CliArgumentStringBuilder.languagePrefix
+import org.jetbrains.kotlin.cli.common.arguments.CliArgumentStringBuilder.replaceLanguageFeature
 import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.idea.configuration.KotlinWithGradleConfigurator.Companion.getBuildScriptSettingsPsiFile
 import org.jetbrains.kotlin.idea.inspections.gradle.GradleHeuristicHelper.PRODUCTION_DEPENDENCY_STATEMENTS
@@ -320,18 +320,7 @@ class KotlinBuildScriptManipulator(
             "listOf(\"$featureArgumentString\")",
             forTests
         ) {
-            val existingFeatureIndex = text.indexOf(feature.name)
-            val languagePrefixIndex = text.lastIndexOf(languagePrefix, existingFeatureIndex)
-            val newText = if (languagePrefixIndex != -1) {
-                text.substring(0, languagePrefixIndex) + featureArgumentString + text.substring(existingFeatureIndex + feature.name.length)
-            } else {
-                val splitText = text.split(")")
-                if (splitText.size != 2) {
-                    "$parameterName = listOf(\"$featureArgumentString\")"
-                } else {
-                    splitText[0] + ", \"$featureArgumentString\")" + splitText[1]
-                }
-            }
+            val newText = text.replaceLanguageFeature(feature, state, prefix = "$parameterName = listOf(", postfix = ")")
             replace(psiFactory.createExpression(newText))
         }
     }
diff --git a/idea/idea-jvm/src/org/jetbrains/kotlin/idea/configuration/KotlinWithLibraryConfigurator.kt b/idea/idea-jvm/src/org/jetbrains/kotlin/idea/configuration/KotlinWithLibraryConfigurator.kt
index 5af5f3f2737..b487f98b3af 100644
--- a/idea/idea-jvm/src/org/jetbrains/kotlin/idea/configuration/KotlinWithLibraryConfigurator.kt
+++ b/idea/idea-jvm/src/org/jetbrains/kotlin/idea/configuration/KotlinWithLibraryConfigurator.kt
@@ -18,6 +18,7 @@ import com.intellij.openapi.vfs.VfsUtil
 import com.intellij.openapi.vfs.VfsUtilCore
 import com.intellij.psi.PsiElement
 import org.jetbrains.annotations.Contract
+import org.jetbrains.kotlin.cli.common.arguments.CliArgumentStringBuilder.replaceLanguageFeature
 import org.jetbrains.kotlin.config.*
 import org.jetbrains.kotlin.idea.facet.getRuntimeLibraryVersion
 import org.jetbrains.kotlin.idea.facet.toApiVersion
@@ -362,10 +363,10 @@ abstract class KotlinWithLibraryConfigurator protected constructor() : KotlinPro
 
         val facetSettings = KotlinFacetSettingsProvider.getInstance(module.project).getInitializedSettings(module)
         ModuleRootModificationUtil.updateModel(module) {
-            facetSettings.apiLevel = LanguageVersion.KOTLIN_1_3
-            facetSettings.languageLevel = LanguageVersion.KOTLIN_1_3
+            facetSettings.apiLevel = feature.sinceVersion
+            facetSettings.languageLevel = feature.sinceVersion
             facetSettings.compilerSettings?.apply {
-                // TODO: JPS, module
+                additionalArguments = additionalArguments.replaceLanguageFeature(feature, state, separator = " ", quoted = false)
             }
         }
     }
diff --git a/idea/idea-jvm/src/org/jetbrains/kotlin/idea/quickfix/ChangeGeneralLanguageFeatureSupportFix.kt b/idea/idea-jvm/src/org/jetbrains/kotlin/idea/quickfix/ChangeGeneralLanguageFeatureSupportFix.kt
index 729615c1985..a47199c4a19 100644
--- a/idea/idea-jvm/src/org/jetbrains/kotlin/idea/quickfix/ChangeGeneralLanguageFeatureSupportFix.kt
+++ b/idea/idea-jvm/src/org/jetbrains/kotlin/idea/quickfix/ChangeGeneralLanguageFeatureSupportFix.kt
@@ -11,6 +11,7 @@ import com.intellij.openapi.module.ModuleUtilCore
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.roots.ModuleRootManager
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.cli.common.arguments.CliArgumentStringBuilder.replaceLanguageFeature
 import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.diagnostics.Diagnostic
 import org.jetbrains.kotlin.idea.compiler.configuration.KotlinCompilerSettings
@@ -55,7 +56,7 @@ sealed class ChangeGeneralLanguageFeatureSupportFix(
                 if (!checkUpdateRuntime(project, feature.sinceApiVersion)) return
             }
             KotlinCompilerSettings.getInstance(project).update {
-                // TODO: JPS, project
+                additionalArguments = additionalArguments.replaceLanguageFeature(feature, featureSupport, separator = " ", quoted = false)
             }
             project.invalidateProjectRoots()
         }
diff --git a/idea/testData/gradle/configurator/enableFeatureSupportToExistentArguments/build.gradle b/idea/testData/gradle/configurator/enableFeatureSupportToExistentArguments/build.gradle
index b22b58c6a64..921a8e27472 100644
--- a/idea/testData/gradle/configurator/enableFeatureSupportToExistentArguments/build.gradle
+++ b/idea/testData/gradle/configurator/enableFeatureSupportToExistentArguments/build.gradle
@@ -19,6 +19,6 @@ dependencies {
 }
 compileKotlin {
     kotlinOptions {
-        freeCompilerArgs = ["-XXLanguage:+SamConversionForKotlinFunctions"]
+        freeCompilerArgs = ["-XXLanguage:+SamConversionForKotlinFunctions"] // Free compiler arguments
     }
 }
diff --git a/idea/testData/gradle/configurator/enableFeatureSupportToExistentArguments/build.gradle.after b/idea/testData/gradle/configurator/enableFeatureSupportToExistentArguments/build.gradle.after
index 1b0db94a1bb..8491200434a 100644
--- a/idea/testData/gradle/configurator/enableFeatureSupportToExistentArguments/build.gradle.after
+++ b/idea/testData/gradle/configurator/enableFeatureSupportToExistentArguments/build.gradle.after
@@ -20,5 +20,6 @@ dependencies {
 compileKotlin {
     kotlinOptions {
         freeCompilerArgs = ["-XXLanguage:+SamConversionForKotlinFunctions", "-XXLanguage:+InlineClasses"]
+        // Free compiler arguments
     }
 }