-- very temp

Don't show notification for new projects
Don't show notification if user doesn't edit kotlin files
Don't show notification when recent files have new code style

.idea/codeStyles/Project.xml

@@ -1,104 +1,7 @@
 <component name="ProjectCodeStyleConfiguration">
   <code_scheme name="Project" version="173">
-    <option name="LINE_SEPARATOR" value="&#10;" />
-    <option name="RIGHT_MARGIN" value="140" />
-    <JavaCodeStyleSettings>
-      <option name="PREFER_LONGER_NAMES" value="false" />
-      <option name="PACKAGES_TO_USE_IMPORT_ON_DEMAND">
-        <value>
-          <package name="java.awt" withSubpackages="false" static="false" />
-          <package name="javax.tools" withSubpackages="true" static="false" />
-          <package name="javax.swing" withSubpackages="false" static="false" />
-        </value>
-      </option>
-    </JavaCodeStyleSettings>
-    <JetCodeStyleSettings>
-      <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
-    </JetCodeStyleSettings>
     <MarkdownNavigatorCodeStyleSettings>
       <option name="RIGHT_MARGIN" value="72" />
     </MarkdownNavigatorCodeStyleSettings>
-    <codeStyleSettings language="HTML">
-      <indentOptions>
-        <option name="INDENT_SIZE" value="2" />
-        <option name="CONTINUATION_INDENT_SIZE" value="4" />
-      </indentOptions>
-    </codeStyleSettings>
-    <codeStyleSettings language="JAVA">
-      <option name="LINE_COMMENT_AT_FIRST_COLUMN" value="false" />
-      <option name="BLOCK_COMMENT_AT_FIRST_COLUMN" value="false" />
-      <option name="KEEP_FIRST_COLUMN_COMMENT" value="false" />
-      <option name="KEEP_BLANK_LINES_BEFORE_RBRACE" value="0" />
-      <option name="ELSE_ON_NEW_LINE" value="true" />
-      <option name="WHILE_ON_NEW_LINE" value="true" />
-      <option name="CATCH_ON_NEW_LINE" value="true" />
-      <option name="FINALLY_ON_NEW_LINE" value="true" />
-      <option name="ALIGN_MULTILINE_PARAMETERS" value="false" />
-      <option name="ALIGN_MULTILINE_PARAMETERS_IN_CALLS" value="true" />
-      <option name="ALIGN_MULTILINE_BINARY_OPERATION" value="true" />
-      <option name="ALIGN_MULTILINE_ASSIGNMENT" value="true" />
-      <option name="ALIGN_MULTILINE_TERNARY_OPERATION" value="true" />
-      <option name="ALIGN_MULTILINE_THROWS_LIST" value="true" />
-      <option name="ALIGN_MULTILINE_EXTENDS_LIST" value="true" />
-      <option name="ALIGN_MULTILINE_PARENTHESIZED_EXPRESSION" value="true" />
-      <option name="SPACE_BEFORE_ARRAY_INITIALIZER_LBRACE" value="true" />
-      <option name="CALL_PARAMETERS_WRAP" value="1" />
-      <option name="METHOD_PARAMETERS_WRAP" value="5" />
-      <option name="METHOD_PARAMETERS_LPAREN_ON_NEXT_LINE" value="true" />
-      <option name="METHOD_PARAMETERS_RPAREN_ON_NEXT_LINE" value="true" />
-      <option name="EXTENDS_LIST_WRAP" value="1" />
-      <option name="THROWS_LIST_WRAP" value="5" />
-      <option name="EXTENDS_KEYWORD_WRAP" value="1" />
-      <option name="THROWS_KEYWORD_WRAP" value="1" />
-      <option name="METHOD_CALL_CHAIN_WRAP" value="1" />
-      <option name="BINARY_OPERATION_WRAP" value="5" />
-      <option name="TERNARY_OPERATION_WRAP" value="5" />
-      <option name="TERNARY_OPERATION_SIGNS_ON_NEXT_LINE" value="true" />
-      <option name="FOR_STATEMENT_WRAP" value="5" />
-      <option name="ARRAY_INITIALIZER_WRAP" value="1" />
-      <option name="ASSIGNMENT_WRAP" value="1" />
-      <option name="IF_BRACE_FORCE" value="1" />
-      <option name="DOWHILE_BRACE_FORCE" value="1" />
-      <option name="WHILE_BRACE_FORCE" value="1" />
-      <option name="FOR_BRACE_FORCE" value="1" />
-      <option name="FIELD_ANNOTATION_WRAP" value="0" />
-    </codeStyleSettings>
-    <codeStyleSettings language="JavaScript">
-      <option name="ELSE_ON_NEW_LINE" value="true" />
-      <option name="WHILE_ON_NEW_LINE" value="true" />
-      <option name="CATCH_ON_NEW_LINE" value="true" />
-      <option name="FINALLY_ON_NEW_LINE" value="true" />
-      <option name="ALIGN_MULTILINE_PARAMETERS_IN_CALLS" value="true" />
-      <option name="ALIGN_MULTILINE_BINARY_OPERATION" value="true" />
-      <option name="ALIGN_MULTILINE_TERNARY_OPERATION" value="true" />
-      <option name="CALL_PARAMETERS_WRAP" value="1" />
-      <option name="METHOD_PARAMETERS_WRAP" value="5" />
-      <option name="BINARY_OPERATION_WRAP" value="5" />
-      <option name="TERNARY_OPERATION_WRAP" value="5" />
-      <option name="TERNARY_OPERATION_SIGNS_ON_NEXT_LINE" value="true" />
-      <option name="FOR_STATEMENT_WRAP" value="5" />
-      <option name="ARRAY_INITIALIZER_WRAP" value="1" />
-      <option name="ASSIGNMENT_WRAP" value="1" />
-      <option name="IF_BRACE_FORCE" value="1" />
-      <option name="DOWHILE_BRACE_FORCE" value="1" />
-      <option name="WHILE_BRACE_FORCE" value="1" />
-      <option name="FOR_BRACE_FORCE" value="1" />
-    </codeStyleSettings>
-    <codeStyleSettings language="PROTO">
-      <indentOptions>
-        <option name="INDENT_SIZE" value="2" />
-        <option name="CONTINUATION_INDENT_SIZE" value="4" />
-      </indentOptions>
-    </codeStyleSettings>
-    <codeStyleSettings language="XML">
-      <indentOptions>
-        <option name="INDENT_SIZE" value="2" />
-        <option name="CONTINUATION_INDENT_SIZE" value="4" />
-      </indentOptions>
-    </codeStyleSettings>
-    <codeStyleSettings language="kotlin">
-      <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
-      <option name="ALIGN_MULTILINE_PARAMETERS_IN_CALLS" value="true" />
-    </codeStyleSettings>
   </code_scheme>
 </component>

.idea/codeStyles/codeStyleConfig.xml

@@ -1,5 +1,5 @@
 <component name="ProjectCodeStyleConfiguration">
   <state>
-    <option name="USE_PER_PROJECT_SETTINGS" value="true" />
+    <option name="PREFERRED_PROJECT_CODE_STYLE" value="Default" />
   </state>
 </component>

.idea/runConfigurations/IDEA.xml

@@ -4,7 +4,7 @@
       <option name="executionName" />
       <option name="externalProjectPath" value="$PROJECT_DIR$" />
       <option name="externalSystemIdString" value="GRADLE" />
-      <option name="scriptParameters" value="" />
+      <option name="scriptParameters" value="--parallel" />
       <option name="taskDescriptions">
         <list />
       </option>
@@ -15,6 +15,6 @@
       </option>
       <option name="vmOptions" value="" />
     </ExternalSystemSettings>
-    <method />
+    <method v="2" />
   </configuration>
 </component>

idea/formatter/src/org/jetbrains/kotlin/idea/core/formatter/KotlinCodeStyleSettings.java

@@ -65,6 +65,9 @@ public class KotlinCodeStyleSettings extends CustomCodeStyleSettings {
     @ReflectionUtil.SkipInEquals
     public String CODE_STYLE_DEFAULTS = null;
 
+    @ReflectionUtil.SkipInEquals
+    public boolean OVERRIDE_PROJECT_DEFAULTS = false;
+
     /**
      * Load settings with previous IDEA defaults to have an ability to restore them.
      */

idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/GradleProperties.kt

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea.configuration
+
+import com.google.common.annotations.VisibleForTesting
+import com.google.common.base.Joiner
+import com.intellij.openapi.externalSystem.util.ExternalSystemApiUtil
+import com.intellij.openapi.project.Project
+import com.intellij.util.SystemProperties
+import org.jetbrains.annotations.NonNls
+import java.io.File
+import java.io.IOException
+import java.util.*
+
+fun getBaseDirPath(project: Project): File {
+    val basePath = project.basePath!!
+    return File(ExternalSystemApiUtil.toCanonicalPath(basePath))
+}
+
+class GradleProperties @Throws(IOException::class) constructor(val path: File) {
+    val properties: Properties
+
+    @Throws(IOException::class)
+    constructor(project: Project) : this(File(getBaseDirPath(project), "gradle.properties"))
+
+    init {
+        properties = PropertiesFiles.getProperties(this.path)
+    }
+
+    @VisibleForTesting
+    internal fun getProperty(name: String): String? {
+        return properties.getProperty(name)
+    }
+
+    @Throws(IOException::class)
+    fun save() {
+        PropertiesFiles.savePropertiesToFile(properties, path, headerComment)
+    }
+
+    fun clear() {
+        properties.clear()
+    }
+
+    companion object {
+        @NonNls
+        private val JVM_ARGS_PROPERTY_NAME = "org.gradle.jvmargs"
+
+        private val headerComment: String
+            get() {
+                val lines = arrayOf(
+                    "# For more details on how to configure your build environment visit",
+                    "# http://www.gradle.org/docs/current/userguide/build_environment.html",
+                    "",
+                    "# Specifies the JVM arguments used for the daemon process.",
+                    "# The setting is particularly useful for tweaking memory settings.",
+                    "# Default value: -Xmx1024m -XX:MaxPermSize=256m",
+                    "# org.gradle.jvmargs=-Xmx2048m -XX:MaxPermSize=512m -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8",
+                    "",
+                    "# When configured, Gradle will run in incubating parallel mode.",
+                    "# This option should only be used with decoupled projects. More details, visit",
+                    "# http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects",
+                    "# org.gradle.parallel=true"
+                )
+                return Joiner.on(SystemProperties.getLineSeparator()).join(lines)
+            }
+
+    }
+}

idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/KotlinGradleSourceSetDataService.kt

@@ -32,6 +32,8 @@ import com.intellij.openapi.roots.impl.libraries.LibraryEx
 import com.intellij.openapi.roots.impl.libraries.LibraryImpl
 import com.intellij.openapi.roots.libraries.PersistentLibraryKind
 import com.intellij.openapi.util.Key
+import com.intellij.psi.codeStyle.CodeStyleSchemes
+import com.intellij.psi.codeStyle.CodeStyleSettingsManager
 import com.intellij.util.PathUtil
 import org.jetbrains.kotlin.cli.common.arguments.K2JSCompilerArguments
 import org.jetbrains.kotlin.cli.common.arguments.K2JVMCompilerArguments
@@ -112,6 +114,16 @@ class KotlinGradleProjectDataService : AbstractProjectDataService<ModuleData, Vo
             val kotlinFacet = configureFacetByGradleModule(ideModule, modelsProvider, moduleNode, null) ?: continue
             GradleProjectImportHandler.getInstances(project).forEach { it.importByModule(kotlinFacet, moduleNode) }
         }
+
+        val property = GradleProperties(project).getProperty("kotlin.code.style")
+        if (property != null) {
+            val schemeManager = CodeStyleSettingsManager.getInstance(project)
+            val currentScheme = CodeStyleSchemes.getInstance().findPreferredScheme(schemeManager.PREFERRED_PROJECT_CODE_STYLE)
+
+            if (currentScheme.isDefault) {
+
+            }
+        }
     }
 }
 

idea/idea-gradle/src/org/jetbrains/kotlin/idea/configuration/PropertiesFiles.kt

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea.configuration
+
+import com.google.common.base.Charsets
+import com.intellij.openapi.util.io.FileUtil
+import java.io.*
+import java.util.*
+
+object PropertiesFiles {
+    @Throws(IOException::class)
+    fun getProperties(filePath: File): Properties {
+        if (filePath.isDirectory) {
+            throw IllegalArgumentException(String.format("The path '%1\$s' belongs to a directory!", filePath.path))
+        }
+        if (!filePath.exists()) {
+            return Properties()
+        }
+        val properties = Properties()
+        InputStreamReader(BufferedInputStream(FileInputStream(filePath)), Charsets.UTF_8).use { reader -> properties.load(reader) }
+        return properties
+    }
+
+    @Throws(IOException::class)
+    fun savePropertiesToFile(properties: Properties, filePath: File, comments: String?) {
+        FileUtil.createParentDirs(filePath)
+        FileOutputStream(filePath).use { out ->
+            // Note that we don't write the properties files in UTF-8; this will *not* write the
+            // files with the default platform encoding; instead, it will write it using ISO-8859-1 and
+            // \\u escaping syntax for other characters. This will work with older versions of the Gradle
+            // plugin which does not read the .properties file with UTF-8 encoding. In the future when
+            // nobody is using older (0.7.x) versions of the Gradle plugin anymore we can upgrade this
+            properties.store(out, comments)
+        }
+    }
+}

idea/idea-jvm/src/org/jetbrains/kotlin/idea/configuration/ui/notifications/NewCodeStyleNotification.kt

@@ -1,108 +0,0 @@
-/*
- * Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- * that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.idea.configuration.ui.notifications
-
-import com.intellij.ide.util.PropertiesComponent
-import com.intellij.notification.*
-import com.intellij.openapi.actionSystem.AnActionEvent
-import com.intellij.openapi.application.ApplicationManager
-import com.intellij.openapi.application.runWriteAction
-import com.intellij.openapi.diagnostic.Logger
-import com.intellij.openapi.project.Project
-import com.intellij.psi.codeStyle.CodeStyleSettingsManager
-import org.jetbrains.kotlin.idea.formatter.*
-import org.jetbrains.kotlin.idea.util.isDefaultOfficialCodeStyle
-
-private const val KOTLIN_UPDATE_CODE_STYLE_GROUP_ID = "Update Kotlin code style"
-private const val KOTLIN_UPDATE_CODE_STYLE_PROPERTY_NAME = "update.kotlin.code.style.notified"
-
-fun notifyKotlinStyleUpdateIfNeeded(project: Project) {
-    if (!isDefaultOfficialCodeStyle) return
-
-    @Suppress("DEPRECATION") // Suggested fix is absent in 173. BUNCH: 181
-    val isProjectSettings = CodeStyleSettingsManager.getInstance(project).USE_PER_PROJECT_SETTINGS
-    val settingsComponent: PropertiesComponent = if (isProjectSettings) {
-        PropertiesComponent.getInstance(project)
-    } else {
-        PropertiesComponent.getInstance()
-    }
-
-    if (settingsComponent.getBoolean(KOTLIN_UPDATE_CODE_STYLE_PROPERTY_NAME, false)) {
-        return
-    }
-
-    val notification = KotlinCodeStyleChangedNotification.create(project, isProjectSettings) ?: return
-    notification.isImportant = true
-
-    NotificationsConfiguration.getNotificationsConfiguration()
-        .register(KOTLIN_UPDATE_CODE_STYLE_GROUP_ID, NotificationDisplayType.STICKY_BALLOON, true)
-
-    if (ApplicationManager.getApplication().isUnitTestMode) {
-        return
-    }
-
-    settingsComponent.setValue(KOTLIN_UPDATE_CODE_STYLE_PROPERTY_NAME, true, false)
-
-    notification.notify(project)
-}
-
-private class KotlinCodeStyleChangedNotification(val project: Project, isProjectSettings: Boolean) : Notification(
-    KOTLIN_UPDATE_CODE_STYLE_GROUP_ID,
-    "Kotlin Code Style",
-    """
-        <html>
-        Default code style was updated to Kotlin Coding Conventions.
-        </html>
-        """.trimIndent(),
-    NotificationType.WARNING,
-    null
-) {
-    init {
-        val ktFormattingSettings = ktCodeStyleSettings(project)
-
-        if (isProjectSettings) {
-            addAction(object : NotificationAction("Apply new code style") {
-                override fun actionPerformed(e: AnActionEvent, notification: Notification) {
-                    notification.expire()
-
-                    val ktSettings = ktCodeStyleSettings(project) ?: return
-
-                    runWriteAction {
-                        KotlinStyleGuideCodeStyle.apply(ktSettings.all)
-                    }
-                }
-            })
-        }
-
-        if (ktFormattingSettings != null && ktFormattingSettings.canRestore()) {
-            addAction(object : NotificationAction("Restore old settings") {
-                override fun actionPerformed(e: AnActionEvent, notification: Notification) {
-                    notification.expire()
-
-                    val ktSettings = ktCodeStyleSettings(project) ?: return
-
-                    runWriteAction {
-                        ktSettings.restore()
-                    }
-                }
-            })
-        }
-    }
-
-    companion object {
-        val LOG = Logger.getInstance("KotlinCodeStyleChangedNotification")
-
-        fun create(project: Project, isProjectSettings: Boolean): KotlinCodeStyleChangedNotification? {
-            val ktFormattingSettings = ktCodeStyleSettings(project) ?: return null
-
-            if (isProjectSettings && !ktFormattingSettings.hasDefaultLoadScheme()) {
-                return null
-            }
-
-            return KotlinCodeStyleChangedNotification(project, isProjectSettings)
-        }
-    }
-}

idea/src/org/jetbrains/kotlin/idea/actions/internal/KotlinFormattingSettingsStatusAction.kt

@@ -8,6 +8,7 @@ package org.jetbrains.kotlin.idea.actions.internal
 import com.intellij.openapi.actionSystem.AnAction
 import com.intellij.openapi.actionSystem.AnActionEvent
 import com.intellij.openapi.ui.Messages
+import org.jetbrains.kotlin.idea.configuration.ui.notifications.KotlinCodeStyleChangedNotification
 import org.jetbrains.kotlin.idea.formatter.KotlinFormatterUsageCollector
 
 class KotlinFormattingSettingsStatusAction : AnAction() {
@@ -15,10 +16,14 @@ class KotlinFormattingSettingsStatusAction : AnAction() {
         val project = e?.project ?: return
 
         val formatterKind = KotlinFormatterUsageCollector.getKotlinFormatterKind(project)
+        val oldStyleRecentFile = KotlinCodeStyleChangedNotification.findRecentFileWithOldCodeStyle(project)
 
         Messages.showInfoMessage(
             project,
-            "formatterKind = $formatterKind",
+            """
+                Formatter kind: $formatterKind
+                Probably old style: ${oldStyleRecentFile?.name ?: "No"}
+            """.trimIndent(),
             "Kotlin Formatter Settings"
         )
     }

idea/src/org/jetbrains/kotlin/idea/configuration/ui/notifications/NewCodeStyleNotification.kt

@@ -0,0 +1,239 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea.configuration.ui.notifications
+
+import com.intellij.ide.util.PropertiesComponent
+import com.intellij.notification.*
+import com.intellij.openapi.actionSystem.AnActionEvent
+import com.intellij.openapi.application.ApplicationManager
+import com.intellij.openapi.application.runWriteAction
+import com.intellij.openapi.diagnostic.Logger
+import com.intellij.openapi.fileEditor.impl.EditorHistoryManager
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiFile
+import com.intellij.psi.PsiManager
+import com.intellij.psi.codeStyle.CodeStyleSettingsManager
+import com.intellij.psi.search.ProjectScope
+import com.intellij.util.ThreeState
+import org.jetbrains.kotlin.idea.KotlinFileType
+import org.jetbrains.kotlin.idea.formatter.*
+import org.jetbrains.kotlin.idea.stubindex.KotlinSourceFilterScope
+import org.jetbrains.kotlin.idea.util.application.runReadAction
+import org.jetbrains.kotlin.idea.util.isDefaultOfficialCodeStyle
+
+private const val KOTLIN_UPDATE_CODE_STYLE_GROUP_ID = "Update Kotlin code style"
+private const val KOTLIN_UPDATE_CODE_STYLE_PROPERTY_NAME = "update.kotlin.code.style.notified"
+
+fun notifyKotlinStyleUpdateIfNeeded(project: Project) {
+    if (!isDefaultOfficialCodeStyle) return
+
+    @Suppress("DEPRECATION") // Suggested fix is absent in 173. BUNCH: 181
+    val isProjectSettings = CodeStyleSettingsManager.getInstance(project).USE_PER_PROJECT_SETTINGS
+    val settingsComponent: PropertiesComponent = if (isProjectSettings) {
+        PropertiesComponent.getInstance(project)
+    } else {
+        PropertiesComponent.getInstance()
+    }
+
+    if (settingsComponent.getBoolean(KOTLIN_UPDATE_CODE_STYLE_PROPERTY_NAME, false)) {
+        return
+    }
+
+    val notification = KotlinCodeStyleChangedNotification.create(project, isProjectSettings) ?: return
+    notification.isImportant = true
+
+    NotificationsConfiguration.getNotificationsConfiguration()
+        .register(KOTLIN_UPDATE_CODE_STYLE_GROUP_ID, NotificationDisplayType.STICKY_BALLOON, true)
+
+    if (ApplicationManager.getApplication().isUnitTestMode) {
+        return
+    }
+
+    settingsComponent.setValue(KOTLIN_UPDATE_CODE_STYLE_PROPERTY_NAME, true, false)
+
+    notification.notify(project)
+}
+
+class KotlinCodeStyleChangedNotification(val project: Project, isProjectSettings: Boolean) : Notification(
+    KOTLIN_UPDATE_CODE_STYLE_GROUP_ID,
+    "Kotlin Code Style",
+    """
+        <html>
+        Default code style was updated to Kotlin Coding Conventions.
+        </html>
+        """.trimIndent(),
+    NotificationType.WARNING,
+    null
+) {
+    init {
+        val ktFormattingSettings = ktCodeStyleSettings(project)
+
+        if (isProjectSettings) {
+            addAction(object : NotificationAction("Apply new code style") {
+                override fun actionPerformed(e: AnActionEvent, notification: Notification) {
+                    notification.expire()
+
+                    val ktSettings = ktCodeStyleSettings(project) ?: return
+
+                    runWriteAction {
+                        KotlinStyleGuideCodeStyle.apply(ktSettings.all)
+                    }
+                }
+            })
+        }
+
+        if (ktFormattingSettings != null && ktFormattingSettings.canRestore()) {
+            addAction(object : NotificationAction("Restore old settings") {
+                override fun actionPerformed(e: AnActionEvent, notification: Notification) {
+                    notification.expire()
+
+                    val ktSettings = ktCodeStyleSettings(project) ?: return
+
+                    runWriteAction {
+                        ktSettings.restore()
+                    }
+                }
+            })
+        }
+    }
+
+    companion object {
+        val LOG = Logger.getInstance("KotlinCodeStyleChangedNotification")
+
+        fun create(project: Project, isProjectSettings: Boolean): KotlinCodeStyleChangedNotification? {
+            val ktFormattingSettings = ktCodeStyleSettings(project) ?: return null
+
+            if (isProjectSettings && !ktFormattingSettings.hasDefaultLoadScheme()) {
+                return null
+            }
+
+            if (findRecentFileWithOldCodeStyle(project) == null) {
+                // User doesn't have recent Kotlin files, or all files are formatted with new code style
+                return null
+            }
+
+            return KotlinCodeStyleChangedNotification(project, isProjectSettings)
+        }
+
+        fun findRecentFileWithOldCodeStyle(project: Project): PsiFile? {
+            val (isOldStyleDetected, oldStyleFiles) = detectIsOldCodeStyleFromRecentFiles(
+                project
+            )
+            if (isOldStyleDetected != ThreeState.YES) {
+                return null
+            }
+
+            return oldStyleFiles.firstOrNull()
+        }
+
+        private data class OldCodeStyleDetectionResult(
+            val result: ThreeState,
+            val oldStyleFiles: Collection<PsiFile>
+        ) {
+            companion object {
+                val UNSURE =
+                    OldCodeStyleDetectionResult(
+                        ThreeState.UNSURE,
+                        emptyList()
+                    )
+            }
+        }
+
+        private fun detectIsOldCodeStyleFromRecentFiles(project: Project): OldCodeStyleDetectionResult {
+            val scope = KotlinSourceFilterScope.projectSources(ProjectScope.getContentScope(project), project)
+            val psiManager = PsiManager.getInstance(project)
+
+            val recentKotlinFiles = EditorHistoryManager.getInstance(project).fileList
+                .filter { it.fileType == KotlinFileType.INSTANCE }
+                .filter { it in scope }
+                .mapNotNull { psiManager.findFile(it) }
+
+            if (recentKotlinFiles.isEmpty()) {
+                return OldCodeStyleDetectionResult.UNSURE
+            }
+
+            val indentWhitespace =
+                indentWhitespace(
+                    project
+                )
+            if (indentWhitespace == null || indentWhitespace.isEmpty()) {
+                return OldCodeStyleDetectionResult.UNSURE
+            }
+
+            val detectToFiles: Map<ThreeState, List<PsiFile>> = recentKotlinFiles
+                .groupBy { file ->
+                    detectOldCodeStyle(
+                        file,
+                        indentWhitespace
+                    )
+                }
+
+            val oldStyleFiles = detectToFiles[ThreeState.YES] ?: emptyList()
+            val newStyleFiles = detectToFiles[ThreeState.NO] ?: emptyList()
+
+            return when {
+                !oldStyleFiles.isEmpty() && !newStyleFiles.isEmpty() ->
+                    OldCodeStyleDetectionResult.UNSURE
+
+                !oldStyleFiles.isEmpty() ->
+                    OldCodeStyleDetectionResult(
+                        ThreeState.YES,
+                        oldStyleFiles
+                    )
+
+                else ->
+                    OldCodeStyleDetectionResult(
+                        ThreeState.NO,
+                        emptyList()
+                    )
+            }
+        }
+
+        private fun indentWhitespace(project: Project): String? {
+            val indentOptions = ktCodeStyleSettings(project)?.common?.indentOptions ?: return null
+            return if (indentOptions.USE_TAB_CHARACTER) "\t" else " ".repeat(indentOptions.INDENT_SIZE)
+        }
+
+        private fun detectOldCodeStyle(ktFile: PsiFile, indentWhitespace: String): ThreeState {
+            val doubleIndent = indentWhitespace + indentWhitespace
+
+            var probablyOldStyleScore = 0
+            var probablyNewCodeStyle = 0
+
+            val text = runReadAction { ktFile.text } ?: return ThreeState.UNSURE
+
+            val lines = text.lines()
+            if (lines.size <= 1) return ThreeState.UNSURE
+
+            for (i in 1..(lines.size - 1)) {
+                val previous = lines[i - 1].trimEnd()
+                val next = lines[i].trimEnd()
+
+                if (previous.endsWith("(") || previous.endsWith("?:") || previous.endsWith("=") ||
+                    next.startsWith(".") || next.startsWith("?.")
+                ) {
+                    val previousIndent = previous.takeWhile { it.isWhitespace() }
+                    val nextIndent = next.takeWhile { it.isWhitespace() }
+
+                    val indent = if (previousIndent.isEmpty()) nextIndent else nextIndent.substringAfter(previousIndent, "")
+                    if (!indent.isEmpty()) {
+                        if (indent == doubleIndent) {
+                            probablyOldStyleScore++
+                        } else if (indent == indentWhitespace) {
+                            probablyNewCodeStyle++
+                        }
+                    }
+                }
+            }
+
+            return when {
+                probablyOldStyleScore > probablyNewCodeStyle -> ThreeState.YES
+                probablyOldStyleScore < probablyNewCodeStyle -> ThreeState.NO
+                else -> ThreeState.UNSURE
+            }
+        }
+    }
+}

idea/src/org/jetbrains/kotlin/idea/formatter/Dialog.form

@@ -0,0 +1,50 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<form xmlns="http://www.intellij.com/uidesigner/form/" version="1" bind-to-class="org.jetbrains.kotlin.idea.formatter.Dialog">
+  <grid id="27dc6" layout-manager="GridLayoutManager" row-count="5" column-count="1" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
+    <margin top="0" left="0" bottom="0" right="0"/>
+    <constraints>
+      <xy x="20" y="20" width="500" height="400"/>
+    </constraints>
+    <properties/>
+    <border type="none"/>
+    <children>
+      <component id="5c703" class="javax.swing.JRadioButton" binding="enableProjectCodeStyleRadioButton" default-binding="true">
+        <constraints>
+          <grid row="1" column="0" row-span="1" col-span="1" vsize-policy="0" hsize-policy="3" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+        </constraints>
+        <properties>
+          <text value="Enable project code style with obsolete code style and share it in VCS"/>
+        </properties>
+      </component>
+      <vspacer id="d426c">
+        <constraints>
+          <grid row="4" column="0" row-span="1" col-span="1" vsize-policy="6" hsize-policy="1" anchor="0" fill="2" indent="0" use-parent-layout="false"/>
+        </constraints>
+      </vspacer>
+      <component id="659a9" class="javax.swing.JRadioButton" binding="enableNewCodeStyleRadioButton" default-binding="true">
+        <constraints>
+          <grid row="2" column="0" row-span="1" col-span="1" vsize-policy="0" hsize-policy="3" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+        </constraints>
+        <properties>
+          <text value="Enable new code style and share it in .idea folder with teammates"/>
+        </properties>
+      </component>
+      <component id="43648" class="javax.swing.JRadioButton" binding="useLocalCodeStyleRadioButton" default-binding="true">
+        <constraints>
+          <grid row="3" column="0" row-span="1" col-span="1" vsize-policy="0" hsize-policy="3" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+        </constraints>
+        <properties>
+          <text value="Use local code style settings with obsolete code style"/>
+        </properties>
+      </component>
+      <component id="79be5" class="javax.swing.JLabel">
+        <constraints>
+          <grid row="0" column="0" row-span="1" col-span="1" vsize-policy="0" hsize-policy="0" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+        </constraints>
+        <properties>
+          <text value="Label"/>
+        </properties>
+      </component>
+    </children>
+  </grid>
+</form>

idea/src/org/jetbrains/kotlin/idea/formatter/Dialog.java

@@ -0,0 +1,14 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea.formatter;
+
+import javax.swing.*;
+
+public class Dialog {
+    private JRadioButton enableProjectCodeStyleRadioButton;
+    private JRadioButton enableNewCodeStyleRadioButton;
+    private JRadioButton useLocalCodeStyleRadioButton;
+}

idea/src/org/jetbrains/kotlin/idea/formatter/KotlinSaveStylePanel.kt

@@ -7,17 +7,8 @@ package org.jetbrains.kotlin.idea.formatter
 
 import com.intellij.application.options.CodeStyleAbstractPanel
 import com.intellij.openapi.editor.colors.EditorColorsScheme
-import com.intellij.openapi.ui.ComboBox
 import com.intellij.psi.codeStyle.CodeStyleSettings
 import com.intellij.ui.ListCellRendererWrapper
-import com.intellij.ui.components.JBScrollPane
-import com.intellij.ui.components.panels.HorizontalLayout
-import com.intellij.ui.components.panels.VerticalLayout
-import com.intellij.util.ui.JBUI
-import com.intellij.util.ui.UIUtil
-import java.awt.BorderLayout
-import javax.swing.BorderFactory
-import javax.swing.JLabel
 import javax.swing.JList
 import javax.swing.JPanel
 
@@ -31,14 +22,13 @@ class KotlinSaveStylePanel(settings: CodeStyleSettings) : CodeStyleAbstractPanel
 
     private data class SaveItem(val label: String, val id: String?)
 
-    private val saveDefaultsComboBox = ComboBox<SaveItem>()
     private val saveDefaultsItems = listOf(
         SaveItem("<ide defaults>", null),
         SaveItem(KotlinObsoleteCodeStyle.CODE_STYLE_TITLE, KotlinObsoleteCodeStyle.CODE_STYLE_ID),
         SaveItem(KotlinStyleGuideCodeStyle.CODE_STYLE_TITLE, KotlinStyleGuideCodeStyle.CODE_STYLE_ID)
     )
 
-    var selectedId: String?
+    private var selectedId: String?
         get() {
             val (_, id) = saveDefaultsComboBox.selectedItem as SaveItem
             return id
@@ -47,44 +37,37 @@ class KotlinSaveStylePanel(settings: CodeStyleSettings) : CodeStyleAbstractPanel
             saveDefaultsComboBox.selectedItem = saveDefaultsItems.firstOrNull { (_, id) -> id == value } ?: saveDefaultsItems.first()
         }
 
-    private val jPanel = JPanel(BorderLayout()).apply {
-        add(
-            JBScrollPane(
-                JPanel(VerticalLayout(JBUI.scale(5))).apply {
-                    border = BorderFactory.createEmptyBorder(UIUtil.DEFAULT_VGAP, 10, UIUtil.DEFAULT_VGAP, 10)
-                    add(JPanel(HorizontalLayout(JBUI.scale(5))).apply {
-                        saveDefaultsItems.forEach {
-                            saveDefaultsComboBox.addItem(it)
-                        }
+    private val loadSaveCodeStyleForm = LoadSaveCodeStyleForm().apply {
+        saveDefaultsItems.forEach {
+            saveDefaultsComboBox.addItem(it)
+        }
 
-                        saveDefaultsComboBox.setRenderer(object : ListCellRendererWrapper<SaveItem>() {
-                            override fun customize(list: JList<*>?, value: SaveItem, index: Int, selected: Boolean, hasFocus: Boolean) {
-                                setText(value.label)
-                            }
-                        })
-
-                        add(JLabel("Use defaults from:"))
-                        add(saveDefaultsComboBox)
-                    })
-                }
-            )
-        )
+        saveDefaultsComboBox.setRenderer(object : ListCellRendererWrapper<SaveItem>() {
+            override fun customize(list: JList<*>?, value: SaveItem, index: Int, selected: Boolean, hasFocus: Boolean) {
+                setText(value.label)
+            }
+        })
     }
 
+    private val saveDefaultsComboBox get() = loadSaveCodeStyleForm.saveDefaultsComboBox
+
     override fun apply(settings: CodeStyleSettings) {
         settings.kotlinCustomSettings.CODE_STYLE_DEFAULTS = selectedId
         settings.kotlinCommonSettings.CODE_STYLE_DEFAULTS = selectedId
+        settings.kotlinCustomSettings.OVERRIDE_PROJECT_DEFAULTS = loadSaveCodeStyleForm.useDefaultObsoleteCodeCheckBox.isSelected
     }
 
     override fun isModified(settings: CodeStyleSettings): Boolean {
         return selectedId != settings.kotlinCustomSettings.CODE_STYLE_DEFAULTS ||
-                selectedId != settings.kotlinCommonSettings.CODE_STYLE_DEFAULTS
+                selectedId != settings.kotlinCommonSettings.CODE_STYLE_DEFAULTS ||
+                loadSaveCodeStyleForm.useDefaultObsoleteCodeCheckBox.isSelected != settings.kotlinCustomSettings.OVERRIDE_PROJECT_DEFAULTS
     }
 
-    override fun getPanel() = jPanel
+    override fun getPanel(): JPanel = loadSaveCodeStyleForm.panel
 
     override fun resetImpl(settings: CodeStyleSettings) {
         selectedId = settings.kotlinCustomSettings.CODE_STYLE_DEFAULTS ?: settings.kotlinCommonSettings.CODE_STYLE_DEFAULTS
+        loadSaveCodeStyleForm.useDefaultObsoleteCodeCheckBox.isSelected = settings.kotlinCustomSettings.OVERRIDE_PROJECT_DEFAULTS
     }
 
     override fun onSomethingChanged() {

idea/src/org/jetbrains/kotlin/idea/formatter/LoadSaveCodeStyleForm.form

@@ -0,0 +1,75 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<form xmlns="http://www.intellij.com/uidesigner/form/" version="1" bind-to-class="org.jetbrains.kotlin.idea.formatter.LoadSaveCodeStyleForm">
+  <grid id="27dc6" binding="panel" layout-manager="GridLayoutManager" row-count="3" column-count="1" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
+    <margin top="5" left="5" bottom="5" right="5"/>
+    <constraints>
+      <xy x="20" y="20" width="500" height="400"/>
+    </constraints>
+    <properties/>
+    <border type="none"/>
+    <children>
+      <grid id="bb269" layout-manager="GridLayoutManager" row-count="1" column-count="3" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
+        <margin top="0" left="0" bottom="0" right="0"/>
+        <constraints>
+          <grid row="0" column="0" row-span="1" col-span="1" vsize-policy="3" hsize-policy="3" anchor="0" fill="3" indent="0" use-parent-layout="false"/>
+        </constraints>
+        <properties/>
+        <border type="none"/>
+        <children>
+          <component id="fc041" class="javax.swing.JLabel">
+            <constraints>
+              <grid row="0" column="0" row-span="1" col-span="1" vsize-policy="0" hsize-policy="0" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+            </constraints>
+            <properties>
+              <text value="Use defaults from:"/>
+            </properties>
+          </component>
+          <hspacer id="747e3">
+            <constraints>
+              <grid row="0" column="2" row-span="1" col-span="1" vsize-policy="1" hsize-policy="6" anchor="0" fill="1" indent="0" use-parent-layout="false"/>
+            </constraints>
+          </hspacer>
+          <component id="6a0af" class="javax.swing.JComboBox" binding="saveDefaultsComboBox">
+            <constraints>
+              <grid row="0" column="1" row-span="1" col-span="1" vsize-policy="0" hsize-policy="2" anchor="8" fill="1" indent="0" use-parent-layout="false"/>
+            </constraints>
+            <properties>
+              <model/>
+            </properties>
+          </component>
+        </children>
+      </grid>
+      <vspacer id="e6a4d">
+        <constraints>
+          <grid row="2" column="0" row-span="1" col-span="1" vsize-policy="6" hsize-policy="1" anchor="0" fill="2" indent="0" use-parent-layout="false"/>
+        </constraints>
+      </vspacer>
+      <grid id="de296" layout-manager="GridLayoutManager" row-count="2" column-count="1" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
+        <margin top="0" left="0" bottom="0" right="0"/>
+        <constraints>
+          <grid row="1" column="0" row-span="1" col-span="1" vsize-policy="3" hsize-policy="3" anchor="0" fill="3" indent="0" use-parent-layout="false"/>
+        </constraints>
+        <properties/>
+        <border type="none"/>
+        <children>
+          <component id="dff62" class="javax.swing.JCheckBox" binding="useDefaultObsoleteCodeCheckBox">
+            <constraints>
+              <grid row="0" column="0" row-span="1" col-span="1" vsize-policy="0" hsize-policy="3" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+            </constraints>
+            <properties>
+              <text value="Use default obsolete code style for this project"/>
+            </properties>
+          </component>
+          <component id="37634" class="javax.swing.JLabel">
+            <constraints>
+              <grid row="1" column="0" row-span="1" col-span="1" vsize-policy="0" hsize-policy="0" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+            </constraints>
+            <properties>
+              <text value="Can be used only with default IDE code style without adjustments"/>
+            </properties>
+          </component>
+        </children>
+      </grid>
+    </children>
+  </grid>
+</form>

idea/src/org/jetbrains/kotlin/idea/formatter/LoadSaveCodeStyleForm.java

@@ -0,0 +1,14 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea.formatter;
+
+import javax.swing.*;
+
+public class LoadSaveCodeStyleForm {
+    public JComboBox saveDefaultsComboBox;
+    public JPanel panel;
+    public JCheckBox useDefaultObsoleteCodeCheckBox;
+}