Address @carreau 's comments

IPython/html/static/notebook/js/codecell.js

@@ -1,573 +1,569
 // Copyright (c) IPython Development Team.
 // Distributed under the terms of the Modified BSD License.
 /**
  *
  *
  * @module codecell
  * @namespace codecell
  * @class CodeCell
  */
 
 
 define([
     'base/js/namespace',
     'jquery',
     'base/js/utils',
     'base/js/keyboard',
     'notebook/js/cell',
     'notebook/js/outputarea',
     'notebook/js/completer',
     'notebook/js/celltoolbar',
     'codemirror/lib/codemirror',
     'codemirror/mode/python/python',
     'notebook/js/codemirror-ipython'
 ], function(IPython, $, utils, keyboard, cell, outputarea, completer, celltoolbar, CodeMirror, cmpython, cmip) {
     "use strict";
     
     var Cell = cell.Cell;
 
     /* local util for codemirror */
     var posEq = function(a, b) {return a.line == b.line && a.ch == b.ch;};
 
     /**
      *
      * function to delete until previous non blanking space character
      * or first multiple of 4 tabstop.
      * @private
      */
     CodeMirror.commands.delSpaceToPrevTabStop = function(cm){
         var from = cm.getCursor(true), to = cm.getCursor(false), sel = !posEq(from, to);
         if (!posEq(from, to)) { cm.replaceRange("", from, to); return; }
         var cur = cm.getCursor(), line = cm.getLine(cur.line);
         var tabsize = cm.getOption('tabSize');
         var chToPrevTabStop = cur.ch-(Math.ceil(cur.ch/tabsize)-1)*tabsize;
         from = {ch:cur.ch-chToPrevTabStop,line:cur.line};
         var select = cm.getRange(from,cur);
         if( select.match(/^\ +$/) !== null){
             cm.replaceRange("",from,cur);
         } else {
             cm.deleteH(-1,"char");
         }
     };
 
     var keycodes = keyboard.keycodes;
 
     var CodeCell = function (kernel, options) {
         // Constructor
         //
         // A Cell conceived to write code.
         //
         // Parameters:
         //  kernel: Kernel instance
         //      The kernel doesn't have to be set at creation time, in that case
         //      it will be null and set_kernel has to be called later.
         //  options: dictionary
         //      Dictionary of keyword arguments.
         //          events: $(Events) instance 
         //          config: dictionary
         //          keyboard_manager: KeyboardManager instance 
         //          notebook: Notebook instance
         //          tooltip: Tooltip instance
         this.kernel = kernel || null;
         this.notebook = options.notebook;
         this.collapsed = false;
         this.events = options.events;
         this.tooltip = options.tooltip;
         this.config = options.config;
 
         // create all attributed in constructor function
         // even if null for V8 VM optimisation
         this.input_prompt_number = null;
         this.celltoolbar = null;
         this.output_area = null;
         // Keep a stack of the 'active' output areas (where active means the 
         // output area that recieves output).  When a user activates an output
         // area, it gets pushed to the stack.  Then, when the output area is
         // deactivated, it's popped from the stack.  When the stack is empty,
         // the cell's output area is used.
         this.active_output_areas = [];
+        var that = this;
+        Object.defineProperty(this, 'active_output_area', {
+            get: function() {
+                if (that.active_output_areas && that.active_output_areas.length > 0) {
+                    return that.active_output_areas[that.active_output_areas.length-1];
+                } else {
+                    return that.output_area;
+                }
+            },
+        });
+
         this.last_msg_id = null;
         this.completer = null;
 
 
         var config = utils.mergeopt(CodeCell, this.config);
         Cell.apply(this,[{
             config: config, 
             keyboard_manager: options.keyboard_manager, 
             events: this.events}]);
 
         // Attributes we want to override in this subclass.
         this.cell_type = "code";
-
-        var that = this;
         this.element.focusout(
             function() { that.auto_highlight(); }
         );
     };
 
     CodeCell.options_default = {
         cm_config : {
             extraKeys: {
                 "Tab" :  "indentMore",
                 "Shift-Tab" : "indentLess",
                 "Backspace" : "delSpaceToPrevTabStop",
                 "Cmd-/" : "toggleComment",
                 "Ctrl-/" : "toggleComment"
             },
             mode: 'ipython',
             theme: 'ipython',
             matchBrackets: true
         }
     };
 
     CodeCell.msg_cells = {};
 
     CodeCell.prototype = Object.create(Cell.prototype);
 
     /**
-     * @method get_output_area
-     */
-    CodeCell.prototype.get_output_area = function () {
-        if (this.active_output_areas && this.active_output_areas.length > 0) {
-            return this.active_output_areas[this.active_output_areas.length-1];
-        } else {
-            return this.output_area;
-        }
-    };
-
-    /**
      * @method push_output_area
      */
     CodeCell.prototype.push_output_area = function (output_area) {
         this.active_output_areas.push(output_area);
     };
 
     /**
      * @method pop_output_area
      */
     CodeCell.prototype.pop_output_area = function (output_area) {
         var index = this.active_output_areas.lastIndexOf(output_area);
         if (index > -1) {
             this.active_output_areas.splice(index, 1);
         }
     };
 
     /**
      * @method auto_highlight
      */
     CodeCell.prototype.auto_highlight = function () {
         this._auto_highlight(this.config.cell_magic_highlight);
     };
 
     /** @method create_element */
     CodeCell.prototype.create_element = function () {
         Cell.prototype.create_element.apply(this, arguments);
 
         var cell =  $('<div></div>').addClass('cell code_cell');
         cell.attr('tabindex','2');
 
         var input = $('<div></div>').addClass('input');
         var prompt = $('<div/>').addClass('prompt input_prompt');
         var inner_cell = $('<div/>').addClass('inner_cell');
         this.celltoolbar = new celltoolbar.CellToolbar({
             cell: this, 
             notebook: this.notebook});
         inner_cell.append(this.celltoolbar.element);
         var input_area = $('<div/>').addClass('input_area');
         this.code_mirror = new CodeMirror(input_area.get(0), this.cm_config);
         this.code_mirror.on('keydown', $.proxy(this.handle_keyevent,this))
         $(this.code_mirror.getInputField()).attr("spellcheck", "false");
         inner_cell.append(input_area);
         input.append(prompt).append(inner_cell);
 
         var widget_area = $('<div/>')
             .addClass('widget-area')
             .hide();
         this.widget_area = widget_area;
         var widget_prompt = $('<div/>')
             .addClass('prompt')
             .appendTo(widget_area);
         var widget_subarea = $('<div/>')
             .addClass('widget-subarea')
             .appendTo(widget_area);
         this.widget_subarea = widget_subarea;
         var widget_clear_buton = $('<button />')
             .addClass('close')
             .html('&times;')
             .click(function() {
                 widget_area.slideUp('', function(){ widget_subarea.html(''); });
                 })
             .appendTo(widget_prompt);
 
         var output = $('<div></div>');
         cell.append(input).append(widget_area).append(output);
         this.element = cell;
         this.output_area = new outputarea.OutputArea({
             selector: output, 
             prompt_area: true, 
             events: this.events, 
             keyboard_manager: this.keyboard_manager});
         this.completer = new completer.Completer(this, this.events);
     };
 
     /** @method bind_events */
     CodeCell.prototype.bind_events = function () {
         Cell.prototype.bind_events.apply(this);
         var that = this;
 
         this.element.focusout(
             function() { that.auto_highlight(); }
         );
     };
 
 
     /**
      *  This method gets called in CodeMirror's onKeyDown/onKeyPress
      *  handlers and is used to provide custom key handling. Its return
      *  value is used to determine if CodeMirror should ignore the event:
      *  true = ignore, false = don't ignore.
      *  @method handle_codemirror_keyevent
      */
     CodeCell.prototype.handle_codemirror_keyevent = function (editor, event) {
 
         var that = this;
         // whatever key is pressed, first, cancel the tooltip request before
         // they are sent, and remove tooltip if any, except for tab again
         var tooltip_closed = null;
         if (event.type === 'keydown' && event.which != keycodes.tab ) {
             tooltip_closed = this.tooltip.remove_and_cancel_tooltip();
         }
 
         var cur = editor.getCursor();
         if (event.keyCode === keycodes.enter){
             this.auto_highlight();
         }
 
         if (event.which === keycodes.down && event.type === 'keypress' && this.tooltip.time_before_tooltip >= 0) {
             // triger on keypress (!) otherwise inconsistent event.which depending on plateform
             // browser and keyboard layout !
             // Pressing '(' , request tooltip, don't forget to reappend it
             // The second argument says to hide the tooltip if the docstring
             // is actually empty
             this.tooltip.pending(that, true);
         } else if ( tooltip_closed && event.which === keycodes.esc && event.type === 'keydown') {
             // If tooltip is active, cancel it.  The call to
             // remove_and_cancel_tooltip above doesn't pass, force=true.
             // Because of this it won't actually close the tooltip
             // if it is in sticky mode. Thus, we have to check again if it is open
             // and close it with force=true.
             if (!this.tooltip._hidden) {
                 this.tooltip.remove_and_cancel_tooltip(true);
             }
             // If we closed the tooltip, don't let CM or the global handlers
             // handle this event.
             event.codemirrorIgnore = true;
             event.preventDefault();
             return true;
         } else if (event.keyCode === keycodes.tab && event.type === 'keydown' && event.shiftKey) {
                 if (editor.somethingSelected() || editor.getSelections().length !== 1){
                     var anchor = editor.getCursor("anchor");
                     var head = editor.getCursor("head");
                     if( anchor.line != head.line){
                         return false;
                     }
                 }
                 this.tooltip.request(that);
                 event.codemirrorIgnore = true;
                 event.preventDefault();
                 return true;
         } else if (event.keyCode === keycodes.tab && event.type == 'keydown') {
             // Tab completion.
             this.tooltip.remove_and_cancel_tooltip();
 
             // completion does not work on multicursor, it might be possible though in some cases
             if (editor.somethingSelected() || editor.getSelections().length > 1) {
                 return false;
             }
             var pre_cursor = editor.getRange({line:cur.line,ch:0},cur);
             if (pre_cursor.trim() === "") {
                 // Don't autocomplete if the part of the line before the cursor
                 // is empty.  In this case, let CodeMirror handle indentation.
                 return false;
             } else {
                 event.codemirrorIgnore = true;
                 event.preventDefault();
                 this.completer.startCompletion();
                 return true;
             }
         } 
         
         // keyboard event wasn't one of those unique to code cells, let's see
         // if it's one of the generic ones (i.e. check edit mode shortcuts)
         return Cell.prototype.handle_codemirror_keyevent.apply(this, [editor, event]);
     };
 
     // Kernel related calls.
 
     CodeCell.prototype.set_kernel = function (kernel) {
         this.kernel = kernel;
     };
 
     /**
      * Execute current code cell to the kernel
      * @method execute
      */
     CodeCell.prototype.execute = function () {
         if (!this.kernel || !this.kernel.is_connected()) {
             console.log("Can't execute, kernel is not connected.");
             return;
         }
 
-        this.get_output_area().clear_output();
+        this.active_output_area.clear_output();
         
         // Clear widget area
         this.widget_subarea.html('');
         this.widget_subarea.height('');
         this.widget_area.height('');
         this.widget_area.hide();
 
         this.set_input_prompt('*');
         this.element.addClass("running");
         if (this.last_msg_id) {
             this.kernel.clear_callbacks_for_msg(this.last_msg_id);
         }
         var callbacks = this.get_callbacks();
         
         var old_msg_id = this.last_msg_id;
         this.last_msg_id = this.kernel.execute(this.get_text(), callbacks, {silent: false, store_history: true});
         if (old_msg_id) {
             delete CodeCell.msg_cells[old_msg_id];
         }
         CodeCell.msg_cells[this.last_msg_id] = this;
         this.render();
     };
     
     /**
      * Construct the default callbacks for
      * @method get_callbacks
      */
     CodeCell.prototype.get_callbacks = function () {
         var that = this;
         return {
             shell : {
                 reply : $.proxy(this._handle_execute_reply, this),
                 payload : {
                     set_next_input : $.proxy(this._handle_set_next_input, this),
                     page : $.proxy(this._open_with_pager, this)
                 }
             },
             iopub : {
                 output : function() { 
-                    var output_area = that.get_output_area();
-                    output_area.handle_output.apply(output_area, arguments);
+                    that.active_output_area.handle_output.apply(output_area, arguments);
                 }, 
                 clear_output : function() { 
-                    var output_area = that.get_output_area();
-                    output_area.handle_clear_output.apply(output_area, arguments);
+                    that.active_output_area.handle_clear_output.apply(output_area, arguments);
                 }, 
             },
             input : $.proxy(this._handle_input_request, this)
         };
     };
     
     CodeCell.prototype._open_with_pager = function (payload) {
         this.events.trigger('open_with_text.Pager', payload);
     };
 
     /**
      * @method _handle_execute_reply
      * @private
      */
     CodeCell.prototype._handle_execute_reply = function (msg) {
         this.set_input_prompt(msg.content.execution_count);
         this.element.removeClass("running");
         this.events.trigger('set_dirty.Notebook', {value: true});
     };
 
     /**
      * @method _handle_set_next_input
      * @private
      */
     CodeCell.prototype._handle_set_next_input = function (payload) {
         var data = {'cell': this, 'text': payload.text};
         this.events.trigger('set_next_input.Notebook', data);
     };
 
     /**
      * @method _handle_input_request
      * @private
      */
     CodeCell.prototype._handle_input_request = function (msg) {
-        this.get_output_area().append_raw_input(msg);
+        this.active_output_area.append_raw_input(msg);
     };
 
 
     // Basic cell manipulation.
 
     CodeCell.prototype.select = function () {
         var cont = Cell.prototype.select.apply(this);
         if (cont) {
             this.code_mirror.refresh();
             this.auto_highlight();
         }
         return cont;
     };
 
     CodeCell.prototype.render = function () {
         var cont = Cell.prototype.render.apply(this);
         // Always execute, even if we are already in the rendered state
         return cont;
     };
     
     CodeCell.prototype.select_all = function () {
         var start = {line: 0, ch: 0};
         var nlines = this.code_mirror.lineCount();
         var last_line = this.code_mirror.getLine(nlines-1);
         var end = {line: nlines-1, ch: last_line.length};
         this.code_mirror.setSelection(start, end);
     };
 
 
     CodeCell.prototype.collapse_output = function () {
         this.output_area.collapse();
     };
 
 
     CodeCell.prototype.expand_output = function () {
         this.output_area.expand();
         this.output_area.unscroll_area();
     };
 
     CodeCell.prototype.scroll_output = function () {
         this.output_area.expand();
         this.output_area.scroll_if_long();
     };
 
     CodeCell.prototype.toggle_output = function () {
         this.output_area.toggle_output();
     };
 
     CodeCell.prototype.toggle_output_scroll = function () {
         this.output_area.toggle_scroll();
     };
 
 
     CodeCell.input_prompt_classical = function (prompt_value, lines_number) {
         var ns;
         if (prompt_value === undefined || prompt_value === null) {
             ns = "&nbsp;";
         } else {
             ns = encodeURIComponent(prompt_value);
         }
         return 'In&nbsp;[' + ns + ']:';
     };
 
     CodeCell.input_prompt_continuation = function (prompt_value, lines_number) {
         var html = [CodeCell.input_prompt_classical(prompt_value, lines_number)];
         for(var i=1; i < lines_number; i++) {
             html.push(['...:']);
         }
         return html.join('<br/>');
     };
 
     CodeCell.input_prompt_function = CodeCell.input_prompt_classical;
 
 
     CodeCell.prototype.set_input_prompt = function (number) {
         var nline = 1;
         if (this.code_mirror !== undefined) {
            nline = this.code_mirror.lineCount();
         }
         this.input_prompt_number = number;
         var prompt_html = CodeCell.input_prompt_function(this.input_prompt_number, nline);
         // This HTML call is okay because the user contents are escaped.
         this.element.find('div.input_prompt').html(prompt_html);
     };
 
 
     CodeCell.prototype.clear_input = function () {
         this.code_mirror.setValue('');
     };
 
 
     CodeCell.prototype.get_text = function () {
         return this.code_mirror.getValue();
     };
 
 
     CodeCell.prototype.set_text = function (code) {
         return this.code_mirror.setValue(code);
     };
 
 
     CodeCell.prototype.clear_output = function (wait) {
-        this.get_output_area().clear_output(wait);
+        this.active_output_area.clear_output(wait);
         this.set_input_prompt();
     };
 
 
     // JSON serialization
 
     CodeCell.prototype.fromJSON = function (data) {
         Cell.prototype.fromJSON.apply(this, arguments);
         if (data.cell_type === 'code') {
             if (data.source !== undefined) {
                 this.set_text(data.source);
                 // make this value the starting point, so that we can only undo
                 // to this state, instead of a blank cell
                 this.code_mirror.clearHistory();
                 this.auto_highlight();
             }
             this.set_input_prompt(data.execution_count);
             this.output_area.trusted = data.metadata.trusted || false;
             this.output_area.fromJSON(data.outputs);
             if (data.metadata.collapsed !== undefined) {
                 if (data.metadata.collapsed) {
                     this.collapse_output();
                 } else {
                     this.expand_output();
                 }
             }
         }
     };
 
 
     CodeCell.prototype.toJSON = function () {
         var data = Cell.prototype.toJSON.apply(this);
         data.source = this.get_text();
         // is finite protect against undefined and '*' value
         if (isFinite(this.input_prompt_number)) {
             data.execution_count = this.input_prompt_number;
         } else {
             data.execution_count = null;
         }
         var outputs = this.output_area.toJSON();
         data.outputs = outputs;
         data.metadata.trusted = this.output_area.trusted;
         data.metadata.collapsed = this.output_area.collapsed;
         return data;
     };
 
     /**
      * handle cell level logic when a cell is unselected
      * @method unselect
      * @return is the action being taken
      */
     CodeCell.prototype.unselect = function () {
         var cont = Cell.prototype.unselect.apply(this);
         if (cont) {
             // When a code cell is usnelected, make sure that the corresponding
             // tooltip and completer to that cell is closed.
             this.tooltip.remove_and_cancel_tooltip(true);
             if (this.completer !== null) {
                 this.completer.close();
             }
         }
         return cont;
     };
 
     // Backwards compatability.
     IPython.CodeCell = CodeCell;
 
     return {'CodeCell': CodeCell};
 });

IPython/html/static/widgets/js/widget_output.js

@@ -1,56 +1,57
 // Copyright (c) IPython Development Team.
 // Distributed under the terms of the Modified BSD License.
 
 define([
     "widgets/js/widget",
     "jquery",
     'notebook/js/outputarea',
-], function(widget, $, outputarea){
+], function(widget, $, outputarea) {
+    'use strict';
 
     var OutputView = widget.DOMWidgetView.extend({
         initialize: function (parameters) {
             // Public constructor
             OutputView.__super__.initialize.apply(this, [parameters]);
             this.model.on('msg:custom', this._handle_route_msg, this);
         },
 
         render: function(){
             // Called when view is rendered.
             this.output_area = new outputarea.OutputArea({
                 selector: this.$el, 
                 prompt_area: false, 
                 events: this.model.widget_manager.notebook.events, 
                 keyboard_manager: this.model.widget_manager.keyboard_manager });
 
             // Make output area reactive.
             var that = this;
             this.output_area.element.on('changed', function() {
                 that.model.set('contents', that.output_area.element.html());
             });
             this.model.on('change:contents', function(){
                 var html = this.model.get('contents');
                 if (this.output_area.element.html() != html) {
                     this.output_area.element.html(html);
                 }
             }, this);
 
             // Set initial contents.
             this.output_area.element.html(this.model.get('contents'));
         },
         
         _handle_route_msg: function(content) {
             var cell = this.options.cell;
             if (content && cell) {
                 if (content.method == 'push') {
                     cell.push_output_area(this.output_area);
                 } else if (content.method == 'pop') {
                     cell.pop_output_area(this.output_area);
                 }
             }
         },
     });
 
     return {
         'OutputView': OutputView,
     };
 });