diff -r 000000000000 -r 6474c204b198 browser/components/tabview/modules/utils.jsm
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/components/tabview/modules/utils.jsm	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,823 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+// **********
+// Title: utils.js
+
+this.EXPORTED_SYMBOLS = ["Point", "Rect", "Range", "Subscribable", "Utils", "MRUList"];
+
+// #########
+const Ci = Components.interfaces;
+const Cu = Components.utils;
+
+Cu.import("resource://gre/modules/Services.jsm");
+
+// ##########
+// Class: Point
+// A simple point.
+//
+// Constructor: Point
+// If a is a Point, creates a copy of it. Otherwise, expects a to be x,
+// and creates a Point with it along with y. If either a or y are omitted,
+// 0 is used in their place.
+this.Point = function Point(a, y) {
+  if (Utils.isPoint(a)) {
+    this.x = a.x;
+    this.y = a.y;
+  } else {
+    this.x = (Utils.isNumber(a) ? a : 0);
+    this.y = (Utils.isNumber(y) ? y : 0);
+  }
+};
+
+Point.prototype = {
+  // ----------
+  // Function: toString
+  // Prints [Point (x,y)] for debug use
+  toString: function Point_toString() {
+    return "[Point (" + this.x + "," + this.y + ")]";
+  },
+
+  // ----------
+  // Function: distance
+  // Returns the distance from this point to the given <Point>.
+  distance: function Point_distance(point) {
+    var ax = this.x - point.x;
+    var ay = this.y - point.y;
+    return Math.sqrt((ax * ax) + (ay * ay));
+  }
+};
+
+// ##########
+// Class: Rect
+// A simple rectangle. Note that in addition to the left and width, it also has
+// a right property; changing one affects the others appropriately. Same for the
+// vertical properties.
+//
+// Constructor: Rect
+// If a is a Rect, creates a copy of it. Otherwise, expects a to be left,
+// and creates a Rect with it along with top, width, and height.
+this.Rect = function Rect(a, top, width, height) {
+  // Note: perhaps 'a' should really be called 'rectOrLeft'
+  if (Utils.isRect(a)) {
+    this.left = a.left;
+    this.top = a.top;
+    this.width = a.width;
+    this.height = a.height;
+  } else {
+    this.left = a;
+    this.top = top;
+    this.width = width;
+    this.height = height;
+  }
+};
+
+Rect.prototype = {
+  // ----------
+  // Function: toString
+  // Prints [Rect (left,top,width,height)] for debug use
+  toString: function Rect_toString() {
+    return "[Rect (" + this.left + "," + this.top + "," +
+            this.width + "," + this.height + ")]";
+  },
+
+  get right() this.left + this.width,
+  set right(value) {
+    this.width = value - this.left;
+  },
+
+  get bottom() this.top + this.height,
+  set bottom(value) {
+    this.height = value - this.top;
+  },
+
+  // ----------
+  // Variable: xRange
+  // Gives you a new <Range> for the horizontal dimension.
+  get xRange() new Range(this.left, this.right),
+
+  // ----------
+  // Variable: yRange
+  // Gives you a new <Range> for the vertical dimension.
+  get yRange() new Range(this.top, this.bottom),
+
+  // ----------
+  // Function: intersects
+  // Returns true if this rectangle intersects the given <Rect>.
+  intersects: function Rect_intersects(rect) {
+    return (rect.right > this.left &&
+            rect.left < this.right &&
+            rect.bottom > this.top &&
+            rect.top < this.bottom);
+  },
+
+  // ----------
+  // Function: intersection
+  // Returns a new <Rect> with the intersection of this rectangle and the give <Rect>,
+  // or null if they don't intersect.
+  intersection: function Rect_intersection(rect) {
+    var box = new Rect(Math.max(rect.left, this.left), Math.max(rect.top, this.top), 0, 0);
+    box.right = Math.min(rect.right, this.right);
+    box.bottom = Math.min(rect.bottom, this.bottom);
+    if (box.width > 0 && box.height > 0)
+      return box;
+
+    return null;
+  },
+
+  // ----------
+  // Function: contains
+  // Returns a boolean denoting if the <Rect> or <Point> is contained inside
+  // this rectangle.
+  //
+  // Parameters
+  //  - A <Rect> or a <Point>
+  contains: function Rect_contains(a) {
+    if (Utils.isPoint(a))
+      return (a.x > this.left &&
+              a.x < this.right &&
+              a.y > this.top &&
+              a.y < this.bottom);
+
+    return (a.left >= this.left &&
+            a.right <= this.right &&
+            a.top >= this.top &&
+            a.bottom <= this.bottom);
+  },
+
+  // ----------
+  // Function: center
+  // Returns a new <Point> with the center location of this rectangle.
+  center: function Rect_center() {
+    return new Point(this.left + (this.width / 2), this.top + (this.height / 2));
+  },
+
+  // ----------
+  // Function: size
+  // Returns a new <Point> with the dimensions of this rectangle.
+  size: function Rect_size() {
+    return new Point(this.width, this.height);
+  },
+
+  // ----------
+  // Function: position
+  // Returns a new <Point> with the top left of this rectangle.
+  position: function Rect_position() {
+    return new Point(this.left, this.top);
+  },
+
+  // ----------
+  // Function: area
+  // Returns the area of this rectangle.
+  area: function Rect_area() {
+    return this.width * this.height;
+  },
+
+  // ----------
+  // Function: inset
+  // Makes the rect smaller (if the arguments are positive) as if a margin is added all around
+  // the initial rect, with the margin widths (symmetric) being specified by the arguments.
+  //
+  // Paramaters
+  //  - A <Point> or two arguments: x and y
+  inset: function Rect_inset(a, b) {
+    if (Utils.isPoint(a)) {
+      b = a.y;
+      a = a.x;
+    }
+
+    this.left += a;
+    this.width -= a * 2;
+    this.top += b;
+    this.height -= b * 2;
+  },
+
+  // ----------
+  // Function: offset
+  // Moves (translates) the rect by the given vector.
+  //
+  // Paramaters
+  //  - A <Point> or two arguments: x and y
+  offset: function Rect_offset(a, b) {
+    if (Utils.isPoint(a)) {
+      this.left += a.x;
+      this.top += a.y;
+    } else {
+      this.left += a;
+      this.top += b;
+    }
+  },
+
+  // ----------
+  // Function: equals
+  // Returns true if this rectangle is identical to the given <Rect>.
+  equals: function Rect_equals(rect) {
+    return (rect.left == this.left &&
+            rect.top == this.top &&
+            rect.width == this.width &&
+            rect.height == this.height);
+  },
+
+  // ----------
+  // Function: union
+  // Returns a new <Rect> with the union of this rectangle and the given <Rect>.
+  union: function Rect_union(a) {
+    var newLeft = Math.min(a.left, this.left);
+    var newTop = Math.min(a.top, this.top);
+    var newWidth = Math.max(a.right, this.right) - newLeft;
+    var newHeight = Math.max(a.bottom, this.bottom) - newTop;
+    var newRect = new Rect(newLeft, newTop, newWidth, newHeight);
+
+    return newRect;
+  },
+
+  // ----------
+  // Function: copy
+  // Copies the values of the given <Rect> into this rectangle.
+  copy: function Rect_copy(a) {
+    this.left = a.left;
+    this.top = a.top;
+    this.width = a.width;
+    this.height = a.height;
+  }
+};
+
+// ##########
+// Class: Range
+// A physical interval, with a min and max.
+//
+// Constructor: Range
+// Creates a Range with the given min and max
+this.Range = function Range(min, max) {
+  if (Utils.isRange(min) && !max) { // if the one variable given is a range, copy it.
+    this.min = min.min;
+    this.max = min.max;
+  } else {
+    this.min = min || 0;
+    this.max = max || 0;
+  }
+};
+
+Range.prototype = {
+  // ----------
+  // Function: toString
+  // Prints [Range (min,max)] for debug use
+  toString: function Range_toString() {
+    return "[Range (" + this.min + "," + this.max + ")]";
+  },
+
+  // Variable: extent
+  // Equivalent to max-min
+  get extent() {
+    return (this.max - this.min);
+  },
+
+  set extent(extent) {
+    this.max = extent - this.min;
+  },
+
+  // ----------
+  // Function: contains
+  // Whether the <Range> contains the given <Range> or value or not.
+  //
+  // Parameters
+  //  - a number or <Range>
+  contains: function Range_contains(value) {
+    if (Utils.isNumber(value))
+      return value >= this.min && value <= this.max;
+    if (Utils.isRange(value))
+      return value.min >= this.min && value.max <= this.max;
+    return false;
+  },
+
+  // ----------
+  // Function: overlaps
+  // Whether the <Range> overlaps with the given <Range> value or not.
+  //
+  // Parameters
+  //  - a number or <Range>
+  overlaps: function Range_overlaps(value) {
+    if (Utils.isNumber(value))
+      return this.contains(value);
+    if (Utils.isRange(value))
+      return !(value.max < this.min || this.max < value.min);
+    return false;
+  },
+
+  // ----------
+  // Function: proportion
+  // Maps the given value to the range [0,1], so that it returns 0 if the value is <= the min,
+  // returns 1 if the value >= the max, and returns an interpolated "proportion" in (min, max).
+  //
+  // Parameters
+  //  - a number
+  //  - (bool) smooth? If true, a smooth tanh-based function will be used instead of the linear.
+  proportion: function Range_proportion(value, smooth) {
+    if (value <= this.min)
+      return 0;
+    if (this.max <= value)
+      return 1;
+
+    var proportion = (value - this.min) / this.extent;
+
+    if (smooth) {
+      // The ease function ".5+.5*Math.tanh(4*x-2)" is a pretty
+      // little graph. It goes from near 0 at x=0 to near 1 at x=1
+      // smoothly and beautifully.
+      // http://www.wolframalpha.com/input/?i=.5+%2B+.5+*+tanh%28%284+*+x%29+-+2%29
+      let tanh = function tanh(x) {
+        var e = Math.exp(x);
+        return (e - 1/e) / (e + 1/e);
+      };
+
+      return .5 - .5 * tanh(2 - 4 * proportion);
+    }
+
+    return proportion;
+  },
+
+  // ----------
+  // Function: scale
+  // Takes the given value in [0,1] and maps it to the associated value on the Range.
+  //
+  // Parameters
+  //  - a number in [0,1]
+  scale: function Range_scale(value) {
+    if (value > 1)
+      value = 1;
+    if (value < 0)
+      value = 0;
+    return this.min + this.extent * value;
+  }
+};
+
+// ##########
+// Class: Subscribable
+// A mix-in for allowing objects to collect subscribers for custom events.
+this.Subscribable = function Subscribable() {
+  this.subscribers = null;
+};
+
+Subscribable.prototype = {
+  // ----------
+  // Function: addSubscriber
+  // The given callback will be called when the Subscribable fires the given event.
+  addSubscriber: function Subscribable_addSubscriber(eventName, callback) {
+    try {
+      Utils.assertThrow(typeof callback == "function", "callback must be a function");
+      Utils.assertThrow(eventName && typeof eventName == "string",
+          "eventName must be a non-empty string");
+    } catch(e) {
+      Utils.log(e);
+      return;
+    }
+
+    if (!this.subscribers)
+      this.subscribers = {};
+
+    if (!this.subscribers[eventName])
+      this.subscribers[eventName] = [];
+
+    let subscribers = this.subscribers[eventName];
+    if (subscribers.indexOf(callback) == -1)
+      subscribers.push(callback);
+  },
+
+  // ----------
+  // Function: removeSubscriber
+  // Removes the subscriber associated with the event for the given callback.
+  removeSubscriber: function Subscribable_removeSubscriber(eventName, callback) {
+    try {
+      Utils.assertThrow(typeof callback == "function", "callback must be a function");
+      Utils.assertThrow(eventName && typeof eventName == "string",
+          "eventName must be a non-empty string");
+    } catch(e) {
+      Utils.log(e);
+      return;
+    }
+
+    if (!this.subscribers || !this.subscribers[eventName])
+      return;
+
+    let subscribers = this.subscribers[eventName];
+    let index = subscribers.indexOf(callback);
+
+    if (index > -1)
+      subscribers.splice(index, 1);
+  },
+
+  // ----------
+  // Function: _sendToSubscribers
+  // Internal routine. Used by the Subscribable to fire events.
+  _sendToSubscribers: function Subscribable__sendToSubscribers(eventName, eventInfo) {
+    try {
+      Utils.assertThrow(eventName && typeof eventName == "string",
+          "eventName must be a non-empty string");
+    } catch(e) {
+      Utils.log(e);
+      return;
+    }
+
+    if (!this.subscribers || !this.subscribers[eventName])
+      return;
+
+    let subsCopy = this.subscribers[eventName].concat();
+    subsCopy.forEach(function (callback) {
+      try {
+        callback(this, eventInfo);
+      } catch(e) {
+        Utils.log(e);
+      }
+    }, this);
+  }
+};
+
+// ##########
+// Class: Utils
+// Singelton with common utility functions.
+this.Utils = {
+  // ----------
+  // Function: toString
+  // Prints [Utils] for debug use
+  toString: function Utils_toString() {
+    return "[Utils]";
+  },
+
+  // ___ Logging
+  useConsole: true, // as opposed to dump
+  showTime: false,
+
+  // ----------
+  // Function: log
+  // Prints the given arguments to the JavaScript error console as a message.
+  // Pass as many arguments as you want, it'll print them all.
+  log: function Utils_log() {
+    var text = this.expandArgumentsForLog(arguments);
+    var prefix = this.showTime ? Date.now() + ': ' : '';
+    if (this.useConsole)    
+      Services.console.logStringMessage(prefix + text);
+    else
+      dump(prefix + text + '\n');
+  },
+
+  // ----------
+  // Function: error
+  // Prints the given arguments to the JavaScript error console as an error.
+  // Pass as many arguments as you want, it'll print them all.
+  error: function Utils_error() {
+    var text = this.expandArgumentsForLog(arguments);
+    var prefix = this.showTime ? Date.now() + ': ' : '';
+    if (this.useConsole)    
+      Cu.reportError(prefix + "tabview error: " + text);
+    else
+      dump(prefix + "TABVIEW ERROR: " + text + '\n');
+  },
+
+  // ----------
+  // Function: trace
+  // Prints the given arguments to the JavaScript error console as a message,
+  // along with a full stack trace.
+  // Pass as many arguments as you want, it'll print them all.
+  trace: function Utils_trace() {
+    var text = this.expandArgumentsForLog(arguments);
+
+    // cut off the first line of the stack trace, because that's just this function.
+    let stack = Error().stack.split("\n").slice(1);
+
+    // if the caller was assert, cut out the line for the assert function as well.
+    if (stack[0].indexOf("Utils_assert(") == 0)
+      stack.splice(0, 1);
+
+    this.log('trace: ' + text + '\n' + stack.join("\n"));
+  },
+
+  // ----------
+  // Function: assert
+  // Prints a stack trace along with label (as a console message) if condition is false.
+  assert: function Utils_assert(condition, label) {
+    if (!condition) {
+      let text;
+      if (typeof label != 'string')
+        text = 'badly formed assert';
+      else
+        text = "tabview assert: " + label;
+
+      this.trace(text);
+    }
+  },
+
+  // ----------
+  // Function: assertThrow
+  // Throws label as an exception if condition is false.
+  assertThrow: function Utils_assertThrow(condition, label) {
+    if (!condition) {
+      let text;
+      if (typeof label != 'string')
+        text = 'badly formed assert';
+      else
+        text = "tabview assert: " + label;
+
+      // cut off the first line of the stack trace, because that's just this function.
+      let stack = Error().stack.split("\n").slice(1);
+
+      throw text + "\n" + stack.join("\n");
+    }
+  },
+
+  // ----------
+  // Function: expandObject
+  // Prints the given object to a string, including all of its properties.
+  expandObject: function Utils_expandObject(obj) {
+    var s = obj + ' = {';
+    for (let prop in obj) {
+      let value;
+      try {
+        value = obj[prop];
+      } catch(e) {
+        value = '[!!error retrieving property]';
+      }
+
+      s += prop + ': ';
+      if (typeof value == 'string')
+        s += '\'' + value + '\'';
+      else if (typeof value == 'function')
+        s += 'function';
+      else
+        s += value;
+
+      s += ', ';
+    }
+    return s + '}';
+  },
+
+  // ----------
+  // Function: expandArgumentsForLog
+  // Expands all of the given args (an array) into a single string.
+  expandArgumentsForLog: function Utils_expandArgumentsForLog(args) {
+    var that = this;
+    return Array.map(args, function(arg) {
+      return typeof arg == 'object' ? that.expandObject(arg) : arg;
+    }).join('; ');
+  },
+
+  // ___ Misc
+
+  // ----------
+  // Function: isLeftClick
+  // Given a DOM mouse event, returns true if it was for the left mouse button.
+  isLeftClick: function Utils_isLeftClick(event) {
+    return event.button == 0;
+  },
+
+  // ----------
+  // Function: isMiddleClick
+  // Given a DOM mouse event, returns true if it was for the middle mouse button.
+  isMiddleClick: function Utils_isMiddleClick(event) {
+    return event.button == 1;
+  },
+
+  // ----------
+  // Function: isRightClick
+  // Given a DOM mouse event, returns true if it was for the right mouse button.
+  isRightClick: function Utils_isRightClick(event) {
+    return event.button == 2;
+  },
+
+  // ----------
+  // Function: isDOMElement
+  // Returns true if the given object is a DOM element.
+  isDOMElement: function Utils_isDOMElement(object) {
+    return object instanceof Ci.nsIDOMElement;
+  },
+
+  // ----------
+  // Function: isValidXULTab
+  // A xulTab is valid if it has not been closed,
+  // and it has not been removed from the DOM
+  // Returns true if the tab is valid.
+  isValidXULTab: function Utils_isValidXULTab(xulTab) {
+    return !xulTab.closing && xulTab.parentNode;
+  },
+
+  // ----------
+  // Function: isNumber
+  // Returns true if the argument is a valid number.
+  isNumber: function Utils_isNumber(n) {
+    return typeof n == 'number' && !isNaN(n);
+  },
+
+  // ----------
+  // Function: isRect
+  // Returns true if the given object (r) looks like a <Rect>.
+  isRect: function Utils_isRect(r) {
+    return (r &&
+            this.isNumber(r.left) &&
+            this.isNumber(r.top) &&
+            this.isNumber(r.width) &&
+            this.isNumber(r.height));
+  },
+
+  // ----------
+  // Function: isRange
+  // Returns true if the given object (r) looks like a <Range>.
+  isRange: function Utils_isRange(r) {
+    return (r &&
+            this.isNumber(r.min) &&
+            this.isNumber(r.max));
+  },
+
+  // ----------
+  // Function: isPoint
+  // Returns true if the given object (p) looks like a <Point>.
+  isPoint: function Utils_isPoint(p) {
+    return (p && this.isNumber(p.x) && this.isNumber(p.y));
+  },
+
+  // ----------
+  // Function: isPlainObject
+  // Check to see if an object is a plain object (created using "{}" or "new Object").
+  isPlainObject: function Utils_isPlainObject(obj) {
+    // Must be an Object.
+    // Make sure that DOM nodes and window objects don't pass through, as well
+    if (!obj || Object.prototype.toString.call(obj) !== "[object Object]" ||
+       obj.nodeType || obj.setInterval) {
+      return false;
+    }
+
+    // Not own constructor property must be Object
+    const hasOwnProperty = Object.prototype.hasOwnProperty;
+
+    if (obj.constructor &&
+       !hasOwnProperty.call(obj, "constructor") &&
+       !hasOwnProperty.call(obj.constructor.prototype, "isPrototypeOf")) {
+      return false;
+    }
+
+    // Own properties are enumerated firstly, so to speed up,
+    // if last one is own, then all properties are own.
+
+    var key;
+    for (key in obj) {}
+
+    return key === undefined || hasOwnProperty.call(obj, key);
+  },
+
+  // ----------
+  // Function: isEmptyObject
+  // Returns true if the given object has no members.
+  isEmptyObject: function Utils_isEmptyObject(obj) {
+    for (let name in obj)
+      return false;
+    return true;
+  },
+
+  // ----------
+  // Function: copy
+  // Returns a copy of the argument. Note that this is a shallow copy; if the argument
+  // has properties that are themselves objects, those properties will be copied by reference.
+  copy: function Utils_copy(value) {
+    if (value && typeof value == 'object') {
+      if (Array.isArray(value))
+        return this.extend([], value);
+      return this.extend({}, value);
+    }
+    return value;
+  },
+
+  // ----------
+  // Function: merge
+  // Merge two array-like objects into the first and return it.
+  merge: function Utils_merge(first, second) {
+    Array.forEach(second, function(el) Array.push(first, el));
+    return first;
+  },
+
+  // ----------
+  // Function: extend
+  // Pass several objects in and it will combine them all into the first object and return it.
+  extend: function Utils_extend() {
+
+    // copy reference to target object
+    let target = arguments[0] || {};
+    // Deep copy is not supported
+    if (typeof target === "boolean") {
+      this.assert(false, "The first argument of extend cannot be a boolean." +
+          "Deep copy is not supported.");
+      return target;
+    }
+
+    // Back when this was in iQ + iQ.fn, so you could extend iQ objects with it.
+    // This is no longer supported.
+    let length = arguments.length;
+    if (length === 1) {
+      this.assert(false, "Extending the iQ prototype using extend is not supported.");
+      return target;
+    }
+
+    // Handle case when target is a string or something
+    if (typeof target != "object" && typeof target != "function") {
+      target = {};
+    }
+
+    for (let i = 1; i < length; i++) {
+      // Only deal with non-null/undefined values
+      let options = arguments[i];
+      if (options != null) {
+        // Extend the base object
+        for (let name in options) {
+          let copy = options[name];
+
+          // Prevent never-ending loop
+          if (target === copy)
+            continue;
+
+          if (copy !== undefined)
+            target[name] = copy;
+        }
+      }
+    }
+
+    // Return the modified object
+    return target;
+  },
+
+  // ----------
+  // Function: attempt
+  // Tries to execute a number of functions. Returns immediately the return
+  // value of the first non-failed function without executing successive
+  // functions, or null.
+  attempt: function Utils_attempt() {
+    let args = arguments;
+
+    for (let i = 0; i < args.length; i++) {
+      try {
+        return args[i]();
+      } catch (e) {}
+    }
+
+    return null;
+  }
+};
+
+// ##########
+// Class: MRUList
+// A most recently used list.
+//
+// Constructor: MRUList
+// If a is an array of entries, creates a copy of it.
+this.MRUList = function MRUList(a) {
+  if (Array.isArray(a))
+    this._list = a.concat();
+  else
+    this._list = [];
+};
+
+MRUList.prototype = {
+  // ----------
+  // Function: toString
+  // Prints [List (entry1, entry2, ...)] for debug use
+  toString: function MRUList_toString() {
+    return "[List (" + this._list.join(", ") + ")]";
+  },
+
+  // ----------
+  // Function: update
+  // Updates/inserts the given entry as the most recently used one in the list.
+  update: function MRUList_update(entry) {
+    this.remove(entry);
+    this._list.unshift(entry);
+  },
+
+  // ----------
+  // Function: remove
+  // Removes the given entry from the list.
+  remove: function MRUList_remove(entry) {
+    let index = this._list.indexOf(entry);
+    if (index > -1)
+      this._list.splice(index, 1);
+  },
+
+  // ----------
+  // Function: peek
+  // Returns the most recently used entry.  If a filter exists, gets the most 
+  // recently used entry which matches the filter.
+  peek: function MRUList_peek(filter) {
+    let match = null;
+    if (filter && typeof filter == "function")
+      this._list.some(function MRUList_peek_getEntry(entry) {
+        if (filter(entry)) {
+          match = entry
+          return true;
+        }
+        return false;
+      });
+    else 
+      match = this._list.length > 0 ? this._list[0] : null;
+
+    return match;
+  },
+};
+