More cleanups

packages/application-extension/src/index.ts

@@ -42,11 +42,13 @@ import {
 
 import { jupyterIcon } from '@jupyter-notebook/ui-components';
 
-import { each } from '@lumino/algorithm';
-
 import { PromiseDelegate } from '@lumino/coreutils';
 
-import { DisposableDelegate, DisposableSet } from '@lumino/disposable';
+import {
+  DisposableDelegate,
+  DisposableSet,
+  IDisposable
+} from '@lumino/disposable';
 
 import { Menu, Widget } from '@lumino/widgets';
 
@@ -605,12 +607,12 @@ const sidebarVisibility: JupyterFrontEndPlugin<void> = {
   ) => {
     const trans = translator.load('notebook');
 
-    const sideBarMenu: SideBarPanel.sideBarMenu = {
+    const sideBarMenu: { [area in SideBarPanel.Area]: IDisposable | null } = {
       left: null,
       right: null
     };
 
-    var sideBarPalette: SideBarPalette | null = null;
+    let sideBarPalette: SideBarPalette | null = null;
 
     /* Arguments for togglePanel command:
      * side, left or right area
@@ -640,7 +642,9 @@ const sidebarVisibility: JupyterFrontEndPlugin<void> = {
           case 'left':
             if (notebookShell.leftCollapsed) {
               notebookShell.expandLeft(args.id as string);
-            } else if (notebookShell.leftHandler.current?.id !== args.id) {
+            } else if (
+              notebookShell.leftHandler.currentWidget?.id !== args.id
+            ) {
               notebookShell.expandLeft(args.id as string);
             } else {
               notebookShell.collapseLeft();
@@ -652,7 +656,9 @@ const sidebarVisibility: JupyterFrontEndPlugin<void> = {
           case 'right':
             if (notebookShell.rightCollapsed) {
               notebookShell.expandRight(args.id as string);
-            } else if (notebookShell.rightHandler.current?.id !== args.id) {
+            } else if (
+              notebookShell.rightHandler.currentWidget?.id !== args.id
+            ) {
               notebookShell.expandRight(args.id as string);
             } else {
               notebookShell.collapseRight();
@@ -664,31 +670,31 @@ const sidebarVisibility: JupyterFrontEndPlugin<void> = {
         }
       },
       isToggled: args => {
-        var currentWidget = null;
         switch (args['side'] as string) {
-          case 'left':
+          case 'left': {
             if (notebookShell.leftCollapsed) {
               return false;
             }
-            currentWidget = notebookShell.leftHandler.current;
+            const currentWidget = notebookShell.leftHandler.currentWidget;
             if (!currentWidget) {
               return false;
             }
 
             return currentWidget.id === (args['id'] as string);
-          case 'right':
+          }
+          case 'right': {
             if (notebookShell.rightCollapsed) {
               return false;
             }
-            currentWidget = notebookShell.rightHandler.current;
+            const currentWidget = notebookShell.rightHandler.currentWidget;
             if (!currentWidget) {
               return false;
             }
 
             return currentWidget.id === (args['id'] as string);
-          default:
-            return false;
+          }
         }
+        return false;
       }
     });
 
@@ -713,7 +719,7 @@ const sidebarVisibility: JupyterFrontEndPlugin<void> = {
       const widgets = notebookShell.widgets(area);
       let menuToAdd = false;
 
-      each(widgets, widget => {
+      for (let widget of widgets) {
         newMenu.addItem({
           command: CommandIDs.togglePanel,
           args: {
@@ -723,7 +729,7 @@ const sidebarVisibility: JupyterFrontEndPlugin<void> = {
           }
         });
         menuToAdd = true;
-      });
+      }
 
       // If there are widgets, add the menu to the main menu entry.
       if (menuToAdd) {
@@ -734,7 +740,13 @@ const sidebarVisibility: JupyterFrontEndPlugin<void> = {
       }
     };
 
-    const getSidebarLabel = (area: SideBarPanel.Area) => {
+    /**
+     * Get a label for a sidebar panel.
+     *
+     * @param area - 'left' or 'right', the area of the side bar.
+     * @returns the label for the sidebar menu entry.
+     */
+    const getSidebarLabel = (area: SideBarPanel.Area): string => {
       if (area === 'left') {
         return trans.__(`Left Sidebar`);
       } else {

packages/application/src/shell.ts

@@ -7,7 +7,6 @@ import { closeIcon } from '@jupyterlab/ui-components';
 
 import { ArrayExt, find } from '@lumino/algorithm';
 import { PromiseDelegate, Token } from '@lumino/coreutils';
-import { IDisposable } from '@lumino/disposable';
 import { Message, MessageLoop, IMessageHandler } from '@lumino/messaging';
 import { ISignal, Signal } from '@lumino/signaling';
 
@@ -176,7 +175,7 @@ export class NotebookShell extends Widget implements JupyterFrontEnd.IShell {
   }
 
   /**
-   * Promise that resolves when main widget is loaded
+   * Promise that resolves when the main widget is loaded
    */
   get restored(): Promise<void> {
     return this._mainWidgetLoaded.promise;
@@ -214,7 +213,7 @@ export class NotebookShell extends Widget implements JupyterFrontEnd.IShell {
    */
   add(
     widget: Widget,
-    area?: string,
+    area?: Shell.Area,
     options?: DocumentRegistry.IOpenOptions
   ): void {
     const rank = options?.rank ?? DEFAULT_RANK;
@@ -359,13 +358,6 @@ export namespace SideBarPanel {
    * The areas of the sidebar panel
    */
   export type Area = 'left' | 'right';
-
-  /**
-   * The sidebar menu type, one for each area
-   */
-  export type sideBarMenu = {
-    [area in Area]: IDisposable | null;
-  };
 }
 
 /**
@@ -380,8 +372,8 @@ export class SideBarHandler {
     this._panel = new Panel();
     this._panel.hide();
 
-    this._current = null;
-    this._lastCurrent = null;
+    this._currentWidget = null;
+    this._lastCurrentWidget = null;
 
     this._widgetPanel = new StackedPanel();
     this._widgetPanel.widgetRemoved.connect(this._onWidgetRemoved, this);
@@ -402,10 +394,13 @@ export class SideBarHandler {
     this._panel.addWidget(this._widgetPanel);
   }
 
-  get current(): Widget | null {
+  /**
+   * Get the current widget in the sidebar panel.
+   */
+  get currentWidget(): Widget | null {
     return (
-      this._current ||
-      this._lastCurrent ||
+      this._currentWidget ||
+      this._lastCurrentWidget ||
       (this._items.length > 0 ? this._items[0].widget : null)
     );
   }
@@ -460,15 +455,15 @@ export class SideBarHandler {
    * if there is no most recently used.
    */
   expand(id?: string): void {
-    if (this._current) {
+    if (this._currentWidget) {
       this.collapse();
     }
     if (id) {
       this.activate(id);
     } else {
-      const visibleWidget = this.current;
+      const visibleWidget = this.currentWidget;
       if (visibleWidget) {
-        this._current = visibleWidget;
+        this._currentWidget = visibleWidget;
         this.activate(visibleWidget.id);
       }
     }
@@ -482,7 +477,7 @@ export class SideBarHandler {
   activate(id: string): void {
     const widget = this._findWidgetByID(id);
     if (widget) {
-      this._current = widget;
+      this._currentWidget = widget;
       widget.show();
       widget.activate();
     }
@@ -499,8 +494,8 @@ export class SideBarHandler {
    * Collapse the sidebar so no items are expanded.
    */
   collapse(): void {
-    this._current?.hide();
-    this._current = null;
+    this._currentWidget?.hide();
+    this._currentWidget = null;
   }
 
   /**
@@ -570,8 +565,8 @@ export class SideBarHandler {
    * Handle the `widgetRemoved` signal from the panel.
    */
   private _onWidgetRemoved(sender: StackedPanel, widget: Widget): void {
-    if (widget === this._lastCurrent) {
-      this._lastCurrent = null;
+    if (widget === this._lastCurrentWidget) {
+      this._lastCurrentWidget = null;
     }
     ArrayExt.removeAt(this._items, this._findWidgetIndex(widget));
 
@@ -585,11 +580,12 @@ export class SideBarHandler {
   private _items = new Array<Private.IRankItem>();
   private _panel: Panel;
   private _widgetPanel: StackedPanel;
-  private _current: Widget | null;
-  private _lastCurrent: Widget | null;
+  private _currentWidget: Widget | null;
+  private _lastCurrentWidget: Widget | null;
   private _widgetAdded: Signal<SideBarHandler, Widget> = new Signal(this);
   private _widgetRemoved: Signal<SideBarHandler, Widget> = new Signal(this);
 }
+
 /**
  * A namespace for private module data.
  */

packages/application/style/sidepanel.css

@@ -30,6 +30,8 @@
 #jp-right-stack .jp-SidePanel-collapse {
   display: flex;
   flex: 0 0 auto;
+  min-height: 0;
+  padding: 0;
 }
 
 #jp-left-stack .jp-SidePanel-collapse {