Disable ForeignHandler by default and add command console:toggle-echo to enable ForeighHandler through context menu

packages/console-extension/src/index.ts

@@ -86,6 +86,9 @@ namespace CommandIDs {
 
   export
   const changeKernel = 'console:change-kernel';
+
+  export
+  const toggleShowAllActivity = 'console:toggle-show-all-kernel-activity';
 }
 
 
@@ -399,6 +402,19 @@ function activateConsole(app: JupyterLab, mainMenu: IMainMenu, palette: ICommand
     isEnabled
   });
 
+  commands.addCommand(CommandIDs.toggleShowAllActivity, {
+    label: args => args['isPalette'] ? 'Toggle Show All Kernel Activity' : 'Show All Kernel Activity',
+
+    execute: args => {
+      let current = getCurrent(args);
+      if (!current) {
+        return;
+      }
+      current.console.showAllActivity = !current.console.showAllActivity;
+    },
+    isToggled: () => tracker.currentWidget ? tracker.currentWidget.console.showAllActivity : false,
+    isEnabled
+  });
   // Add command palette items
   [
     CommandIDs.create,
@@ -410,6 +426,7 @@ function activateConsole(app: JupyterLab, mainMenu: IMainMenu, palette: ICommand
     CommandIDs.interrupt,
     CommandIDs.changeKernel,
     CommandIDs.closeAndShutdown,
+    CommandIDs.toggleShowAllActivity,
   ].forEach(command => {
     palette.addItem({ command, category, args: { 'isPalette': true } });
   });
@@ -487,6 +504,7 @@ function activateConsole(app: JupyterLab, mainMenu: IMainMenu, palette: ICommand
 
   app.contextMenu.addItem({command: CommandIDs.clear, selector: '.jp-CodeConsole-content'});
   app.contextMenu.addItem({command: CommandIDs.restart, selector: '.jp-CodeConsole'});
+  app.contextMenu.addItem({command: CommandIDs.toggleShowAllActivity, selector: '.jp-CodeConsole'});
 
   return tracker;
 }

packages/console/src/foreign.ts

@@ -160,7 +160,7 @@ class ForeignHandler implements IDisposable {
   }
 
   private _cells = new Map<string, CodeCell>();
-  private _enabled = true;
+  private _enabled = false;
   private _parent: ForeignHandler.IReceiver;
   private _factory: () => CodeCell;
   private _isDisposed = false;

packages/console/src/widget.ts

@@ -274,6 +274,17 @@ class CodeConsole extends Widget {
     super.dispose();
   }
 
+  /**
+   * Set whether the foreignHandler is able to inject foreign cells into a
+   * console.
+   */
+  get showAllActivity(): boolean {
+    return this._foreignHandler.enabled;
+  }
+  set showAllActivity(value: boolean) {
+    this._foreignHandler.enabled = value;
+  }
+
   /**
    * Execute the current prompt.
    *

tests/test-console/src/foreign.spec.ts

@@ -147,12 +147,13 @@ describe('@jupyterlab/console', () => {
 
     describe('#enabled', () => {
 
-      it('should default to `true`', () => {
-        expect(handler.enabled).to.be(true);
+      it('should default to `false`', () => {
+        expect(handler.enabled).to.be(false);
       });
 
       it('should allow foreign cells to be injected if `true`', done => {
         let code = 'print("#enabled:true")';
+        handler.enabled = true;
         handler.injected.connect(() => { done(); });
         foreign.kernel.requestExecute({ code, stop_on_error: true });
       });
@@ -224,6 +225,7 @@ describe('@jupyterlab/console', () => {
 
       it('should inject relevant cells into the parent', done => {
         let code = 'print("#onIOPubMessage:enabled")';
+        handler.enabled = true;
         let parent = handler.parent as TestParent;
         expect(parent.widgets.length).to.be(0);
         handler.injected.connect(() => {
@@ -236,6 +238,7 @@ describe('@jupyterlab/console', () => {
       it('should not reject relevant iopub messages', done => {
         let code = 'print("#onIOPubMessage:relevant")';
         let called = 0;
+        handler.enabled = true;
         handler.rejected.connect(() => {
           done(new Error('rejected relevant iopub message'));
         });

tests/test-console/src/widget.spec.ts

@@ -104,6 +104,7 @@ describe('console/widget', () => {
 
       it('should reflect the contents of the widget', () => {
         let force = true;
+        widget.showAllActivity = true;
         Widget.attach(widget, document.body);
         return (widget.session as ClientSession).initialize().then(() => {
           return widget.execute(force);