Support modifying 'setting.gradle.kts' as well.

Test dsl will update 'settings.gradle.kts' with required plugin
management block.

^KT-45745 In Progress

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/testbase/projectSetupDefaults.kt

@@ -24,6 +24,7 @@ internal val DEFAULT_GROOVY_SETTINGS_FILE =
             id "org.jetbrains.kotlin.android" version "${'$'}kotlin_version"
             id "org.jetbrains.kotlin.js" version "${'$'}kotlin_version"
             id "org.jetbrains.kotlin.multiplatform" version "${'$'}kotlin_version"
+            id "org.jetbrains.kotlin.test.fixes.android" version "${'$'}kotlin_version"
         }
         
         resolutionStrategy {
@@ -48,3 +49,44 @@ internal val DEFAULT_GROOVY_SETTINGS_FILE =
         }
     }
     """.trimIndent()
+
+@Language("kts")
+internal val DEFAULT_KOTLIN_SETTINGS_FILE =
+    """
+    pluginManagement {
+        repositories {
+            mavenLocal()
+            mavenCentral()
+            google()
+            gradlePluginPortal()
+        }
+
+        val kotlin_version: String by settings
+        val android_tools_version: String by settings
+        plugins {
+            id("org.jetbrains.kotlin.jvm") version kotlin_version
+            id("org.jetbrains.kotlin.kapt") version kotlin_version
+            id("org.jetbrains.kotlin.android") version kotlin_version
+            id("org.jetbrains.kotlin.js") version kotlin_version
+            id("org.jetbrains.kotlin.multiplatform") version kotlin_version
+            id("org.jetbrains.kotlin.test.fixes.android") version kotlin_version
+        }
+        
+        resolutionStrategy {
+            eachPlugin {
+                when (requested.id.id) {
+                    "com.android.application",
+                    "com.android.library",
+                    "com.android.test",
+                    "com.android.dynamic-feature",
+                    "com.android.asset-pack",
+                    "com.android.asset-pack-bundle",
+                    "com.android.lint",
+                    "com.android.instantapp",
+                    "com.android.feature" -> useModule("com.android.tools.build:gradle:${'$'}android_tools_version")
+                    "kotlin-dce-js" -> useModule("org.jetbrains.kotlin:kotlin-gradle-plugin:${'$'}kotlin_version")        
+                }
+            }
+        }
+    }
+    """.trimIndent()

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/testbase/testDsl.kt

@@ -290,32 +290,33 @@ private fun Path.addDefaultBuildFiles() {
     }
 }
 
-private fun Path.addPluginManagementToSettings() {
+internal fun Path.addPluginManagementToSettings() {
     val settingsGradle = resolve("settings.gradle")
     val settingsGradleKts = resolve("settings.gradle.kts")
-    val fileToUpdate = when {
+    when {
-        Files.exists(settingsGradle) -> settingsGradle
+        Files.exists(settingsGradle) -> settingsGradle.modify {
-        Files.exists(settingsGradleKts) -> settingsGradleKts
+            if (!it.contains("pluginManagement {")) {
-        else -> null
-    }
-
-    if (fileToUpdate == null) {
-        settingsGradle.toFile().writeText(DEFAULT_GROOVY_SETTINGS_FILE)
-    } else {
-        val settingsContent = fileToUpdate.toFile().readText()
-        if (!settingsContent
-                .lines()
-                .first { !it.startsWith("//") }
-                .startsWith("pluginManagement {")
-        ) {
-            fileToUpdate.toFile().writeText(
                 """
-                    $DEFAULT_GROOVY_SETTINGS_FILE
+                |$DEFAULT_GROOVY_SETTINGS_FILE
-                    
+                |                    
-                    $settingsContent
+                |$it
-                    """.trimIndent()
+                |""".trimMargin()
-            )
+            } else {
+                it
+            }
         }
+        Files.exists(settingsGradleKts) -> settingsGradleKts.modify {
+            if (!it.contains("pluginManagement {")) {
+                """
+                |$DEFAULT_KOTLIN_SETTINGS_FILE
+                |
+                |$it
+                """.trimMargin()
+            } else {
+                it
+            }
+        }
+        else -> settingsGradle.toFile().writeText(DEFAULT_GROOVY_SETTINGS_FILE)
     }
 }