Add Project View and Navigation Bar enhancements

Add local declarations to Project View
Show Kotlin file members in navigation bar (Fixed #KT-36218)
Remove deprecated dependency

idea/src/org/jetbrains/kotlin/idea/codeInsight/BreadcrumbsProviderCompatBase.kt

@@ -0,0 +1,11 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.codeInsight
+
+import com.intellij.xml.breadcrumbs.BreadcrumbsInfoProvider
+
+// BUNCH 201
+typealias BreadcrumbsProviderCompatBase = BreadcrumbsInfoProvider

idea/src/org/jetbrains/kotlin/idea/codeInsight/BreadcrumbsProviderCompatBase.kt.201

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.codeInsight
+
+import com.intellij.ide.ui.UISettings
+import com.intellij.ui.breadcrumbs.BreadcrumbsProvider
+
+// BUNCH 201
+abstract class BreadcrumbsProviderCompatBase : BreadcrumbsProvider {
+    override fun isShownByDefault(): Boolean =
+        !UISettings.instance.showMembersInNavigationBar
+}

idea/src/org/jetbrains/kotlin/idea/codeInsight/KotlinBreadcrumbsInfoProvider.kt

@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- *
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- * 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.codeInsight
@@ -22,7 +11,6 @@ import com.intellij.psi.ElementDescriptionUtil
 import com.intellij.psi.PsiElement
 import com.intellij.refactoring.util.RefactoringDescriptionLocation
 import com.intellij.usageView.UsageViewShortNameLocation
-import com.intellij.xml.breadcrumbs.BreadcrumbsInfoProvider
 import org.jetbrains.kotlin.KtNodeTypes
 import org.jetbrains.kotlin.idea.KotlinBundle
 import org.jetbrains.kotlin.idea.KotlinLanguage
@@ -35,7 +23,8 @@ import org.jetbrains.kotlin.renderer.render
 import org.jetbrains.kotlin.resolve.calls.callUtil.getValueArgumentsInParentheses
 import kotlin.reflect.KClass
 
-class KotlinBreadcrumbsInfoProvider : BreadcrumbsInfoProvider() {
+// BUNCH 201
+class KotlinBreadcrumbsInfoProvider : BreadcrumbsProviderCompatBase() {
     private abstract class ElementHandler<TElement : KtElement>(val type: KClass<TElement>) {
         abstract fun elementInfo(element: TElement): String
         abstract fun elementTooltip(element: TElement): String

idea/src/org/jetbrains/kotlin/idea/navigationToolbar/AbstractNavBarModelExtensionCompatBase.kt

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.navigationToolbar
+
+import com.intellij.ide.navigationToolbar.AbstractNavBarModelExtension
+import com.intellij.psi.PsiElement
+
+// BUNCH 201
+abstract class AbstractNavBarModelExtensionCompatBase : AbstractNavBarModelExtension() {
+
+    protected abstract fun adjustElementImpl(psiElement: PsiElement?): PsiElement?
+
+    override fun adjustElement(psiElement: PsiElement): PsiElement? =
+        adjustElementImpl(psiElement)
+}

idea/src/org/jetbrains/kotlin/idea/navigationToolbar/AbstractNavBarModelExtensionCompatBase.kt.201

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.navigationToolbar
+
+import com.intellij.ide.navigationToolbar.StructureAwareNavBarModelExtension
+import com.intellij.lang.Language
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.idea.KotlinLanguage
+
+// BUNCH 201
+abstract class AbstractNavBarModelExtensionCompatBase : StructureAwareNavBarModelExtension() {
+
+    protected abstract fun adjustElementImpl(psiElement: PsiElement?): PsiElement?
+
+    override fun adjustElement(psiElement: PsiElement): PsiElement? =
+        adjustElementImpl(psiElement)
+
+    override val language: Language
+        get() = KotlinLanguage.INSTANCE
+}

idea/src/org/jetbrains/kotlin/idea/navigationToolbar/KotlinNavBarModelExtension.kt

@@ -5,21 +5,18 @@
 
 package org.jetbrains.kotlin.idea.navigationToolbar
 
-import com.intellij.ide.navigationToolbar.AbstractNavBarModelExtension
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.idea.KotlinIconProvider
-import org.jetbrains.kotlin.psi.KtClassOrObject
+import org.jetbrains.kotlin.idea.projectView.KtDeclarationTreeNode.Companion.tryGetRepresentableText
+import org.jetbrains.kotlin.psi.KtDeclaration
 import org.jetbrains.kotlin.psi.KtFile
 
-class KotlinNavBarModelExtension : AbstractNavBarModelExtension() {
+// BUNCH 201
-    override fun getPresentableText(item: Any?): String? {
+class KotlinNavBarModelExtension : AbstractNavBarModelExtensionCompatBase() {
-        return when (item) {
+    override fun getPresentableText(item: Any?): String? =
-            is KtClassOrObject -> item.name ?: "unknown"
+        (item as? KtDeclaration)?.let { tryGetRepresentableText(it, it.project) }
-            else -> null
-        }
-    }
 
-    override fun adjustElement(psiElement: PsiElement?): PsiElement? {
+    override fun adjustElementImpl(psiElement: PsiElement?): PsiElement? {
         val containingFile = psiElement?.containingFile as? KtFile ?: return psiElement
         if (containingFile.isScript()) return psiElement
         return KotlinIconProvider.getSingleClass(containingFile) ?: psiElement

idea/src/org/jetbrains/kotlin/idea/navigationToolbar/KotlinNavBarModelExtension.kt.201

@@ -1,27 +0,0 @@
-/*
- * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * 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.navigationToolbar
-
-import com.intellij.ide.navigationToolbar.AbstractNavBarModelExtension
-import com.intellij.psi.PsiElement
-import org.jetbrains.kotlin.idea.KotlinIconProvider
-import org.jetbrains.kotlin.psi.KtClassOrObject
-import org.jetbrains.kotlin.psi.KtFile
-
-class KotlinNavBarModelExtension : AbstractNavBarModelExtension() {
-    override fun getPresentableText(item: Any?): String? {
-        return when (item) {
-            is KtClassOrObject -> item.name ?: "unknown"
-            else -> null
-        }
-    }
-
-    override fun adjustElement(psiElement: PsiElement): PsiElement? {
-        val containingFile = psiElement.containingFile as? KtFile ?: return psiElement
-        if (containingFile.isScript()) return psiElement
-        return KotlinIconProvider.getSingleClass(containingFile) ?: psiElement
-    }
-}

idea/src/org/jetbrains/kotlin/idea/projectView/KtClassOrObjectTreeNode.kt

@@ -34,8 +34,9 @@ class KtClassOrObjectTreeNode(project: Project?, ktClassOrObject: KtClassOrObjec
     }
 
     override fun updateImpl(data: PresentationData) {
+        val project = project ?: return
         value?.let {
-            data.presentableText = it.name
+            data.presentableText = KtDeclarationTreeNode.tryGetRepresentableText(it, project)
         }
     }
 
@@ -75,5 +76,7 @@ class KtClassOrObjectTreeNode(project: Project?, ktClassOrObject: KtClassOrObjec
         return false
     }
 
+    override fun expandOnDoubleClick(): Boolean = false
+
     override fun getWeight() = 20
 }

idea/src/org/jetbrains/kotlin/idea/projectView/KtDeclarationTreeNode.java

@@ -1,111 +0,0 @@
-/*
- * Copyright 2010-2015 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.projectView;
-
-import com.intellij.application.options.CodeStyle;
-import com.intellij.ide.projectView.PresentationData;
-import com.intellij.ide.projectView.ViewSettings;
-import com.intellij.ide.projectView.impl.nodes.AbstractPsiBasedNode;
-import com.intellij.ide.util.treeView.AbstractTreeNode;
-import com.intellij.openapi.project.Project;
-import com.intellij.psi.PsiElement;
-import org.jetbrains.kotlin.idea.KotlinBundle;
-import org.jetbrains.kotlin.idea.core.formatter.KotlinCodeStyleSettings;
-import org.jetbrains.kotlin.psi.*;
-
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-
-public class KtDeclarationTreeNode extends AbstractPsiBasedNode<KtDeclaration> {
-    public static final String CLASS_INITIALIZER = "<" + KotlinBundle.message("project.view.class.initializer") + ">";
-
-    protected KtDeclarationTreeNode(Project project, KtDeclaration ktDeclaration, ViewSettings viewSettings) {
-        super(project, ktDeclaration, viewSettings);
-    }
-
-    @Override
-    protected PsiElement extractPsiFromValue() {
-        return getValue();
-    }
-
-    @Override
-    protected Collection<AbstractTreeNode> getChildrenImpl() {
-        return Collections.emptyList();
-    }
-
-    @Override
-    protected void updateImpl(PresentationData data) {
-        KtDeclaration declaration = getValue();
-        if (declaration != null) {
-            String text = declaration instanceof KtAnonymousInitializer ? CLASS_INITIALIZER : declaration.getName();
-            if (text == null) return;
-
-            KotlinCodeStyleSettings settings = CodeStyle.getSettings(getProject())
-                    .getCustomSettings(KotlinCodeStyleSettings.class);
-
-            if (declaration instanceof KtProperty) {
-                KtProperty property = (KtProperty) declaration;
-                KtTypeReference ref = property.getTypeReference();
-                if (ref != null) {
-                    if (settings.SPACE_BEFORE_TYPE_COLON) text += " ";
-                    text += ":";
-                    if (settings.SPACE_AFTER_TYPE_COLON) text += " ";
-                    text += ref.getText();
-                }
-            }
-            else if (declaration instanceof KtFunction) {
-                KtFunction function = (KtFunction) declaration;
-                KtTypeReference receiverTypeRef = function.getReceiverTypeReference();
-                if (receiverTypeRef != null) {
-                    text = receiverTypeRef.getText() + "." + text;
-                }
-                text += "(";
-                List<KtParameter> parameters = function.getValueParameters();
-                for (KtParameter parameter : parameters) {
-                    if (parameter.getName() != null) {
-                        text += parameter.getName();
-                        if (settings.SPACE_BEFORE_TYPE_COLON) text += " ";
-                        text += ":";
-                        if (settings.SPACE_AFTER_TYPE_COLON) text += " ";
-                    }
-                    KtTypeReference typeReference = parameter.getTypeReference();
-                    if (typeReference != null) {
-                        text += typeReference.getText();
-                    }
-                    text += ", ";
-                }
-                if (parameters.size() > 0) text = text.substring(0, text.length() - 2);
-                text += ")";
-                KtTypeReference typeReference = function.getTypeReference();
-                if (typeReference != null) {
-                    if (settings.SPACE_BEFORE_TYPE_COLON) text += " ";
-                    text += ":";
-                    if (settings.SPACE_AFTER_TYPE_COLON) text += " ";
-                    text += typeReference.getText();
-                }
-            }
-
-            data.setPresentableText(text);
-        }
-    }
-
-    @Override
-    protected boolean isDeprecated() {
-        return KtPsiUtil.isDeprecated(getValue());
-    }
-}

idea/src/org/jetbrains/kotlin/idea/projectView/KtDeclarationTreeNode.java.201

@@ -1,111 +0,0 @@
-/*
- * Copyright 2010-2015 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.projectView;
-
-import com.intellij.application.options.CodeStyle;
-import com.intellij.ide.projectView.PresentationData;
-import com.intellij.ide.projectView.ViewSettings;
-import com.intellij.ide.projectView.impl.nodes.AbstractPsiBasedNode;
-import com.intellij.ide.util.treeView.AbstractTreeNode;
-import com.intellij.openapi.project.Project;
-import com.intellij.psi.PsiElement;
-import org.jetbrains.kotlin.idea.KotlinBundle;
-import org.jetbrains.kotlin.idea.core.formatter.KotlinCodeStyleSettings;
-import org.jetbrains.kotlin.psi.*;
-
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-
-public class KtDeclarationTreeNode extends AbstractPsiBasedNode<KtDeclaration> {
-    public static final String CLASS_INITIALIZER = "<" + KotlinBundle.message("project.view.class.initializer") + ">";
-
-    protected KtDeclarationTreeNode(Project project, KtDeclaration ktDeclaration, ViewSettings viewSettings) {
-        super(project, ktDeclaration, viewSettings);
-    }
-
-    @Override
-    protected PsiElement extractPsiFromValue() {
-        return getValue();
-    }
-
-    @Override
-    protected Collection<AbstractTreeNode<?>> getChildrenImpl() {
-        return Collections.emptyList();
-    }
-
-    @Override
-    protected void updateImpl(PresentationData data) {
-        KtDeclaration declaration = getValue();
-        if (declaration != null) {
-            String text = declaration instanceof KtAnonymousInitializer ? CLASS_INITIALIZER : declaration.getName();
-            if (text == null) return;
-
-            KotlinCodeStyleSettings settings = CodeStyle.getSettings(getProject())
-                    .getCustomSettings(KotlinCodeStyleSettings.class);
-
-            if (declaration instanceof KtProperty) {
-                KtProperty property = (KtProperty) declaration;
-                KtTypeReference ref = property.getTypeReference();
-                if (ref != null) {
-                    if (settings.SPACE_BEFORE_TYPE_COLON) text += " ";
-                    text += ":";
-                    if (settings.SPACE_AFTER_TYPE_COLON) text += " ";
-                    text += ref.getText();
-                }
-            }
-            else if (declaration instanceof KtFunction) {
-                KtFunction function = (KtFunction) declaration;
-                KtTypeReference receiverTypeRef = function.getReceiverTypeReference();
-                if (receiverTypeRef != null) {
-                    text = receiverTypeRef.getText() + "." + text;
-                }
-                text += "(";
-                List<KtParameter> parameters = function.getValueParameters();
-                for (KtParameter parameter : parameters) {
-                    if (parameter.getName() != null) {
-                        text += parameter.getName();
-                        if (settings.SPACE_BEFORE_TYPE_COLON) text += " ";
-                        text += ":";
-                        if (settings.SPACE_AFTER_TYPE_COLON) text += " ";
-                    }
-                    KtTypeReference typeReference = parameter.getTypeReference();
-                    if (typeReference != null) {
-                        text += typeReference.getText();
-                    }
-                    text += ", ";
-                }
-                if (parameters.size() > 0) text = text.substring(0, text.length() - 2);
-                text += ")";
-                KtTypeReference typeReference = function.getTypeReference();
-                if (typeReference != null) {
-                    if (settings.SPACE_BEFORE_TYPE_COLON) text += " ";
-                    text += ":";
-                    if (settings.SPACE_AFTER_TYPE_COLON) text += " ";
-                    text += typeReference.getText();
-                }
-            }
-
-            data.setPresentableText(text);
-        }
-    }
-
-    @Override
-    protected boolean isDeprecated() {
-        return KtPsiUtil.isDeprecated(getValue());
-    }
-}

idea/src/org/jetbrains/kotlin/idea/projectView/KtDeclarationTreeNode.kt

@@ -0,0 +1,149 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.projectView
+
+import com.intellij.application.options.CodeStyle
+import com.intellij.ide.projectView.PresentationData
+import com.intellij.ide.projectView.ViewSettings
+import com.intellij.ide.projectView.impl.nodes.AbstractPsiBasedNode
+import com.intellij.ide.util.treeView.AbstractTreeNode
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.idea.KotlinBundle
+import org.jetbrains.kotlin.idea.core.formatter.KotlinCodeStyleSettings
+import org.jetbrains.kotlin.psi.*
+
+internal class KtDeclarationTreeNode(
+    project: Project?,
+    ktDeclaration: KtDeclaration?,
+    viewSettings: ViewSettings?
+) : AbstractPsiBasedNode<KtDeclaration?>(project, ktDeclaration!!, viewSettings) {
+
+    override fun extractPsiFromValue(): PsiElement? = value
+
+    override fun getChildrenImpl(): Collection<AbstractTreeNode<*>> {
+        val settings = settings
+        val project = project
+
+        if (!settings.isShowMembers) return emptyList()
+        val declaration = value ?: return emptyList()
+
+        val result = mutableListOf<AbstractTreeNode<*>>()
+        declaration.acceptChildren(object : KtTreeVisitorVoid() {
+            override fun visitClassOrObject(classOrObject: KtClassOrObject) {
+                result.add(
+                    KtClassOrObjectTreeNode(
+                        project = project,
+                        ktClassOrObject = classOrObject,
+                        viewSettings = settings
+                    )
+                )
+            }
+
+            override fun visitNamedFunction(function: KtNamedFunction) {
+                result.add(
+                    KtDeclarationTreeNode(
+                        project = project,
+                        ktDeclaration = function,
+                        viewSettings = settings
+                    )
+                )
+            }
+        })
+
+        return result
+    }
+
+    override fun updateImpl(data: PresentationData) {
+        val declaration = value ?: return
+        val project = project ?: return
+        data.presentableText = tryGetRepresentableText(declaration, project)
+    }
+
+    override fun expandOnDoubleClick(): Boolean = false
+
+    override fun isDeprecated(): Boolean = value?.let { KtPsiUtil.isDeprecated(it) } ?: false
+
+    companion object {
+        private val CLASS_INITIALIZER = "<" + KotlinBundle.message("project.view.class.initializer") + ">"
+
+        fun tryGetRepresentableText(declaration: KtDeclaration, project: Project): String? {
+
+            val settings = CodeStyle.getSettings(project).getCustomSettings(KotlinCodeStyleSettings::class.java)
+            fun StringBuilder.appendColon() {
+                if (settings.SPACE_BEFORE_TYPE_COLON) append(" ")
+                append(":")
+                if (settings.SPACE_AFTER_TYPE_COLON) append(" ")
+            }
+
+            fun KtProperty.presentableText() = buildString {
+                append(name)
+                typeReference?.text?.let { reference ->
+                    appendColon()
+                    append(reference)
+                }
+            }
+
+            fun KtFunction.presentableText() = buildString {
+                receiverTypeReference?.text?.let { receiverReference ->
+                    append(receiverReference)
+                    append('.')
+                }
+                append(name)
+                append("(")
+                val valueParameters = valueParameters
+                valueParameters.forEachIndexed { index, parameter ->
+                    parameter.name?.let { parameterName ->
+                        append(parameterName)
+                        appendColon()
+                    }
+                    parameter.typeReference?.text?.let { typeReference ->
+                        append(typeReference)
+                    }
+                    if (index != valueParameters.size - 1) {
+                        append(", ")
+                    }
+                }
+                append(")")
+
+                typeReference?.text?.let { returnTypeReference ->
+                    appendColon()
+                    append(returnTypeReference)
+                }
+            }
+
+            fun KtObjectDeclaration.presentableText(): String? = buildString {
+
+                if (isCompanion()) {
+                    append("companion object")
+                } else {
+                    append("object")
+                    if (!name.isNullOrEmpty()) {
+                        append(" $name")
+                    }
+                }
+
+                if (superTypeListEntries.any()) {
+                    appendColon()
+                    val lastIndex = superTypeListEntries.size - 1
+                    superTypeListEntries.forEachIndexed { index, entry ->
+                        entry.typeReference?.text?.let {
+                            if (index > 0 && index != lastIndex) append(", ")
+                            append(it)
+                        }
+                    }
+                }
+            }
+
+            return when (declaration) {
+                is KtProperty -> declaration.presentableText()
+                is KtFunction -> declaration.presentableText()
+                is KtObjectDeclaration -> declaration.presentableText()
+                is KtAnonymousInitializer -> CLASS_INITIALIZER
+                else -> declaration.name
+            }
+        }
+    }
+}

idea/src/org/jetbrains/kotlin/idea/projectView/KtFileTreeNode.java

@@ -1,63 +0,0 @@
-/*
- * Copyright 2010-2015 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.projectView;
-
-import com.intellij.ide.projectView.ViewSettings;
-import com.intellij.ide.projectView.impl.nodes.PsiFileNode;
-import com.intellij.ide.util.treeView.AbstractTreeNode;
-import com.intellij.openapi.project.Project;
-import org.jetbrains.kotlin.psi.KtClassOrObject;
-import org.jetbrains.kotlin.psi.KtDeclaration;
-import org.jetbrains.kotlin.psi.KtFile;
-
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-
-public class KtFileTreeNode extends PsiFileNode {
-    public KtFileTreeNode(Project project, KtFile value, ViewSettings viewSettings) {
-        super(project, value, viewSettings);
-    }
-
-    public final KtFile getKtFile() {
-        return (KtFile) getValue();
-    }
-
-    @Override
-    public Collection<AbstractTreeNode> getChildrenImpl() {
-        KtFile file = (KtFile) getValue();
-
-        if (file == null) return Collections.emptyList();
-        ArrayList<AbstractTreeNode> result = new ArrayList<AbstractTreeNode>();
-
-        if (getSettings().isShowMembers()) {
-            @SuppressWarnings("ConstantConditions") List<KtDeclaration> declarations = (file.isScript() ? file.getScript() : file).getDeclarations();
-
-            for (KtDeclaration declaration : declarations) {
-                if (declaration instanceof KtClassOrObject) {
-                    result.add(new KtClassOrObjectTreeNode(file.getProject(), (KtClassOrObject) declaration, getSettings()));
-                }
-                else if (getSettings().isShowMembers()) {
-                    result.add(new KtDeclarationTreeNode(getProject(), declaration, getSettings()));
-                }
-            }
-        }
-
-        return result;
-    }
-}

idea/src/org/jetbrains/kotlin/idea/projectView/KtFileTreeNode.java.201

@@ -1,63 +0,0 @@
-/*
- * Copyright 2010-2015 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.projectView;
-
-import com.intellij.ide.projectView.ViewSettings;
-import com.intellij.ide.projectView.impl.nodes.PsiFileNode;
-import com.intellij.ide.util.treeView.AbstractTreeNode;
-import com.intellij.openapi.project.Project;
-import org.jetbrains.kotlin.psi.KtClassOrObject;
-import org.jetbrains.kotlin.psi.KtDeclaration;
-import org.jetbrains.kotlin.psi.KtFile;
-
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-
-public class KtFileTreeNode extends PsiFileNode {
-    public KtFileTreeNode(Project project, KtFile value, ViewSettings viewSettings) {
-        super(project, value, viewSettings);
-    }
-
-    public final KtFile getKtFile() {
-        return (KtFile) getValue();
-    }
-
-    @Override
-    public Collection<AbstractTreeNode<?>> getChildrenImpl() {
-        KtFile file = (KtFile) getValue();
-
-        if (file == null) return Collections.emptyList();
-        ArrayList<AbstractTreeNode<?>> result = new ArrayList<>();
-
-        if (getSettings().isShowMembers()) {
-            @SuppressWarnings("ConstantConditions") List<KtDeclaration> declarations = (file.isScript() ? file.getScript() : file).getDeclarations();
-
-            for (KtDeclaration declaration : declarations) {
-                if (declaration instanceof KtClassOrObject) {
-                    result.add(new KtClassOrObjectTreeNode(file.getProject(), (KtClassOrObject) declaration, getSettings()));
-                }
-                else if (getSettings().isShowMembers()) {
-                    result.add(new KtDeclarationTreeNode(getProject(), declaration, getSettings()));
-                }
-            }
-        }
-
-        return result;
-    }
-}

idea/src/org/jetbrains/kotlin/idea/projectView/KtFileTreeNode.kt

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.projectView
+
+import com.intellij.ide.projectView.ViewSettings
+import com.intellij.ide.projectView.impl.nodes.PsiFileNode
+import com.intellij.ide.util.treeView.AbstractTreeNode
+import com.intellij.openapi.project.Project
+import org.jetbrains.kotlin.psi.KtClassOrObject
+import org.jetbrains.kotlin.psi.KtFile
+
+class KtFileTreeNode(
+    project: Project?,
+    val ktFile: KtFile,
+    viewSettings: ViewSettings
+) : PsiFileNode(project, ktFile, viewSettings) {
+
+    override fun getChildrenImpl(): Collection<AbstractTreeNode<*>> {
+        if (!settings.isShowMembers) return emptyList()
+
+        val declarations = (if (ktFile.isScript()) ktFile.script else ktFile)
+            ?.declarations
+            ?: return emptyList()
+
+        return declarations.map {
+            if (it is KtClassOrObject)
+                KtClassOrObjectTreeNode(project, it, settings)
+            else
+                KtDeclarationTreeNode(project, it, settings)
+        }
+    }
+}