- Add binary size analysis tool from Chromium.

runtime/third_party/binary_size/src/template/D3SymbolTreeMap.js

Index: runtime/third_party/binary_size/src/template/D3SymbolTreeMap.js
diff --git a/runtime/third_party/binary_size/src/template/D3SymbolTreeMap.js b/runtime/third_party/binary_size/src/template/D3SymbolTreeMap.js
new file mode 100644
index 0000000000000000000000000000000000000000..4bbe82f1a32624b35abdaa148f9ded73dfe08384
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+++ b/runtime/third_party/binary_size/src/template/D3SymbolTreeMap.js
@@ -0,0 +1,938 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// TODO:
+// 1. Visibility functions: base on boxPadding.t, not 15
+// 2. Track a maxDisplayDepth that is user-settable:
+//    maxDepth == currentRoot.depth + maxDisplayDepth
+function D3SymbolTreeMap(mapWidth, mapHeight, levelsToShow) {
+  this._mapContainer = undefined;
+  this._mapWidth = mapWidth;
+  this._mapHeight = mapHeight;
+  this.boxPadding = {'l': 5, 'r': 5, 't': 20, 'b': 5};
+  this.infobox = undefined;
+  this._maskContainer = undefined;
+  this._highlightContainer = undefined;
+  // Transition in this order:
+  // 1. Exiting items go away.
+  // 2. Updated items move.
+  // 3. New items enter.
+  this._exitDuration=500;
+  this._updateDuration=500;
+  this._enterDuration=500;
+  this._firstTransition=true;
+  this._layout = undefined;
+  this._currentRoot = undefined;
+  this._currentNodes = undefined;
+  this._treeData = undefined;
+  this._maxLevelsToShow = levelsToShow;
+  this._currentMaxDepth = this._maxLevelsToShow;
+}
+
+/**
+ * Make a number pretty, with comma separators.
+ */
+D3SymbolTreeMap._pretty = function(num) {
+  var asString = String(num);
+  var result = '';
+  var counter = 0;
+  for (var x = asString.length - 1; x >= 0; x--) {
+    counter++;
+    if (counter === 4) {
+      result = ',' + result;
+      counter = 1;
+    }
+    result = asString.charAt(x) + result;
+  }
+  return result;
+}
+
+/**
+ * Express a number in terms of KiB, MiB, GiB, etc.
+ * Note that these are powers of 2, not of 10.
+ */
+D3SymbolTreeMap._byteify = function(num) {
+  var suffix;
+  if (num >= 1024) {
+    if (num >= 1024 * 1024 * 1024) {
+      suffix = 'GiB';
+      num = num / (1024 * 1024 * 1024);
+    } else if (num >= 1024 * 1024) {
+      suffix = 'MiB';
+      num = num / (1024 * 1024);
+    } else if (num >= 1024) {
+      suffix = 'KiB'
+      num = num / 1024;
+    }
+    return num.toFixed(2) + ' ' + suffix;
+  }
+  return num + ' B';
+}
+
+D3SymbolTreeMap._NM_SYMBOL_TYPE_DESCRIPTIONS = {
+  // Definitions concisely derived from the nm 'man' page
+  'A': 'Global absolute (A)',
+  'B': 'Global uninitialized data (B)',
+  'b': 'Local uninitialized data (b)',
+  'C': 'Global uninitialized common (C)',
+  'D': 'Global initialized data (D)',
+  'd': 'Local initialized data (d)',
+  'G': 'Global small initialized data (G)',
+  'g': 'Local small initialized data (g)',
+  'i': 'Indirect function (i)',
+  'N': 'Debugging (N)',
+  'p': 'Stack unwind (p)',
+  'R': 'Global read-only data (R)',
+  'r': 'Local read-only data (r)',
+  'S': 'Global small uninitialized data (S)',
+  's': 'Local small uninitialized data (s)',
+  'T': 'Global code (T)',
+  't': 'Local code (t)',
+  'U': 'Undefined (U)',
+  'u': 'Unique (u)',
+  'V': 'Global weak object (V)',
+  'v': 'Local weak object (v)',
+  'W': 'Global weak symbol (W)',
+  'w': 'Local weak symbol (w)',
+  '@': 'Vtable entry (@)', // non-standard, hack.
+  '-': 'STABS debugging (-)',
+  '?': 'Unrecognized (?)',
+};
+D3SymbolTreeMap._NM_SYMBOL_TYPES = '';
+for (var symbol_type in D3SymbolTreeMap._NM_SYMBOL_TYPE_DESCRIPTIONS) {
+  D3SymbolTreeMap._NM_SYMBOL_TYPES += symbol_type;
+}
+
+/**
+ * Given a symbol type code, look up and return a human-readable description
+ * of that symbol type. If the symbol type does not match one of the known
+ * types, the unrecognized description (corresponding to symbol type '?') is
+ * returned instead of null or undefined.
+ */
+D3SymbolTreeMap._getSymbolDescription = function(type) {
+  var result = D3SymbolTreeMap._NM_SYMBOL_TYPE_DESCRIPTIONS[type];
+  if (result === undefined) {
+    result = D3SymbolTreeMap._NM_SYMBOL_TYPE_DESCRIPTIONS['?'];
+  }
+  return result;
+}
+
+// Qualitative 12-value pastel Brewer palette.
+D3SymbolTreeMap._colorArray = [
+  'rgb(141,211,199)',
+  'rgb(255,255,179)',
+  'rgb(190,186,218)',
+  'rgb(251,128,114)',
+  'rgb(128,177,211)',
+  'rgb(253,180,98)',
+  'rgb(179,222,105)',
+  'rgb(252,205,229)',
+  'rgb(217,217,217)',
+  'rgb(188,128,189)',
+  'rgb(204,235,197)',
+  'rgb(255,237,111)'];
+
+D3SymbolTreeMap._initColorMap = function() {
+  var map = {};
+  var numColors = D3SymbolTreeMap._colorArray.length;
+  var count = 0;
+  for (var key in D3SymbolTreeMap._NM_SYMBOL_TYPE_DESCRIPTIONS) {
+    var index = count++ % numColors;
+    map[key] = d3.rgb(D3SymbolTreeMap._colorArray[index]);
+  }
+  D3SymbolTreeMap._colorMap = map;
+}
+D3SymbolTreeMap._initColorMap();
+
+D3SymbolTreeMap.getColorForType = function(type) {
+  var result = D3SymbolTreeMap._colorMap[type];
+  if (result === undefined) return d3.rgb('rgb(255,255,255)');
+  return result;
+}
+
+D3SymbolTreeMap.prototype.init = function() {
+  this.infobox = this._createInfoBox();
+  this._mapContainer = d3.select('body').append('div')
+      .style('position', 'relative')
+      .style('width', this._mapWidth)
+      .style('height', this._mapHeight)
+      .style('padding', 0)
+      .style('margin', 0)
+      .style('box-shadow', '5px 5px 5px #888');
+  this._layout = this._createTreeMapLayout();
+  this._setData(tree_data); // TODO: Don't use global 'tree_data'
+}
+
+/**
+ * Sets the data displayed by the treemap and layint out the map.
+ */
+D3SymbolTreeMap.prototype._setData = function(data) {
+  this._treeData = data;
+  console.time('_crunchStats');
+  this._crunchStats(data);
+  console.timeEnd('_crunchStats');
+  this._currentRoot = this._treeData;
+  this._currentNodes = this._layout.nodes(this._currentRoot);
+  this._currentMaxDepth = this._maxLevelsToShow;
+  this._doLayout();
+}
+
+/**
+ * Recursively traverses the entire tree starting from the specified node,
+ * computing statistics and recording metadata as it goes. Call this method
+ * only once per imported tree.
+ */
+D3SymbolTreeMap.prototype._crunchStats = function(node) {
+  var stack = [];
+  stack.idCounter = 0;
+  this._crunchStatsHelper(stack, node);
+}
+
+/**
+ * Invoke the specified visitor function on all data elements currently shown
+ * in the treemap including any and all of their children, starting at the
+ * currently-displayed root and descening recursively. The function will be
+ * passed the datum element representing each node. No traversal guarantees
+ * are made.
+ */
+D3SymbolTreeMap.prototype.visitFromDisplayedRoot = function(visitor) {
+  this._visit(this._currentRoot, visitor);
+}
+
+/**
+ * Helper function for visit functions.
+ */
+D3SymbolTreeMap.prototype._visit = function(datum, visitor) {
+  visitor.call(this, datum);
+  if (datum.children) for (var i = 0; i < datum.children.length; i++) {
+    this._visit(datum.children[i], visitor);
+  }
+}
+
+D3SymbolTreeMap.prototype._crunchStatsHelper = function(stack, node) {
+  // Only overwrite the node ID if it isn't already set.
+  // This allows stats to be crunched multiple times on subsets of data
+  // without breaking the data-to-ID bindings. New nodes get new IDs.
+  if (node.id === undefined) node.id = stack.idCounter++;
+  if (node.children === undefined) {
+    // Leaf node (symbol); accumulate stats.
+    for (var i = 0; i < stack.length; i++) {
+      var ancestor = stack[i];
+      if (!ancestor.symbol_stats) ancestor.symbol_stats = {};
+      if (ancestor.symbol_stats[node.t] === undefined) {
+        // New symbol type we haven't seen before, just record.
+        ancestor.symbol_stats[node.t] = {'count': 1,
+                                         'size': node.value};
+      } else {
+        // Existing symbol type, increment.
+        ancestor.symbol_stats[node.t].count++;
+        ancestor.symbol_stats[node.t].size += node.value;
+      }
+    }
+  } else for (var i = 0; i < node.children.length; i++) {
+    stack.push(node);
+    this._crunchStatsHelper(stack, node.children[i]);
+    stack.pop();
+  }
+}
+
+D3SymbolTreeMap.prototype._createTreeMapLayout = function() {
+  var result = d3.layout.treemap()
+      .padding([this.boxPadding.t, this.boxPadding.r,
+                this.boxPadding.b, this.boxPadding.l])
+      .size([this._mapWidth, this._mapHeight]);
+  return result;
+}
+
+D3SymbolTreeMap.prototype.resize = function(width, height) {
+  this._mapWidth = width;
+  this._mapHeight = height;
+  this._mapContainer.style('width', width).style('height', height);
+  this._layout.size([this._mapWidth, this._mapHeight]);
+  this._currentNodes = this._layout.nodes(this._currentRoot);
+  this._doLayout();
+}
+
+D3SymbolTreeMap.prototype._zoomDatum = function(datum) {
+  if (this._currentRoot === datum) return; // already here
+  this._hideHighlight(datum);
+  this._hideInfoBox(datum);
+  this._currentRoot = datum;
+  this._currentNodes = this._layout.nodes(this._currentRoot);
+  this._currentMaxDepth = this._currentRoot.depth + this._maxLevelsToShow;
+  console.log('zooming into datum ' + this._currentRoot.n);
+  this._doLayout();
+}
+
+D3SymbolTreeMap.prototype.setMaxLevels = function(levelsToShow) {
+  this._maxLevelsToShow = levelsToShow;
+  this._currentNodes = this._layout.nodes(this._currentRoot);
+  this._currentMaxDepth = this._currentRoot.depth + this._maxLevelsToShow;
+  console.log('setting max levels to show: ' + this._maxLevelsToShow);
+  this._doLayout();
+}
+
+/**
+ * Clone the specified tree, returning an independent copy of the data.
+ * Only the original attributes expected to exist prior to invoking
+ * _crunchStatsHelper are retained, with the exception of the 'id' attribute
+ * (which must be retained for proper transitions).
+ * If the optional filter parameter is provided, it will be called with 'this'
+ * set to this treemap instance and passed the 'datum' object as an argument.
+ * When specified, the copy will retain only the data for which the filter
+ * function returns true.
+ */
+D3SymbolTreeMap.prototype._clone = function(datum, filter) {
+  var trackingStats = false;
+  if (this.__cloneState === undefined) {
+    console.time('_clone');
+    trackingStats = true;
+    this.__cloneState = {'accepted': 0, 'rejected': 0,
+                         'forced': 0, 'pruned': 0};
+  }
+
+  // Must go depth-first. All parents of children that are accepted by the
+  // filter must be preserved!
+  var copy = {'n': datum.n, 'k': datum.k};
+  var childAccepted = false;
+  if (datum.children !== undefined) {
+    for (var i = 0; i < datum.children.length; i++) {
+      var copiedChild = this._clone(datum.children[i], filter);
+      if (copiedChild !== undefined) {
+        childAccepted = true; // parent must also be accepted.
+        if (copy.children === undefined) copy.children = [];
+        copy.children.push(copiedChild);
+      }
+    }
+  }
+
+  // Ignore nodes that don't match the filter, when present.
+  var accept = false;
+  if (childAccepted) {
+    // Parent of an accepted child must also be accepted.
+    this.__cloneState.forced++;
+    accept = true;
+  } else if (filter !== undefined && filter.call(this, datum) !== true) {
+    this.__cloneState.rejected++;
+  } else if (datum.children === undefined) {
+    // Accept leaf nodes that passed the filter
+    this.__cloneState.accepted++;
+    accept = true;
+  } else {
+    // Non-leaf node. If no children are accepted, prune it.
+    this.__cloneState.pruned++;
+  }
+
+  if (accept) {
+    if (datum.id !== undefined) copy.id = datum.id;
+    if (datum.lastPathElement !== undefined) {
+      copy.lastPathElement = datum.lastPathElement;
+    }
+    if (datum.t !== undefined) copy.t = datum.t;
+    if (datum.value !== undefined && datum.children === undefined) {
+      copy.value = datum.value;
+    }
+  } else {
+    // Discard the copy we were going to return
+    copy = undefined;
+  }
+
+  if (trackingStats === true) {
+    // We are the fist call in the recursive chain.
+    console.timeEnd('_clone');
+    var totalAccepted = this.__cloneState.accepted +
+                        this.__cloneState.forced;
+    console.log(
+        totalAccepted + ' nodes retained (' +
+        this.__cloneState.forced + ' forced by accepted children, ' +
+        this.__cloneState.accepted + ' accepted on their own merits), ' +
+        this.__cloneState.rejected + ' nodes (and their children) ' +
+                                     'filtered out,' +
+        this.__cloneState.pruned + ' nodes pruned because because no ' +
+                                   'children remained.');
+    delete this.__cloneState;
+  }
+  return copy;
+}
+
+D3SymbolTreeMap.prototype.filter = function(filter) {
+  // Ensure we have a copy of the original root.
+  if (this._backupTree === undefined) this._backupTree = this._treeData;
+  this._mapContainer.selectAll('div').remove();
+  this._setData(this._clone(this._backupTree, filter));
+}
+
+D3SymbolTreeMap.prototype._doLayout = function() {
+  console.time('_doLayout');
+  this._handleInodes();
+  this._handleLeaves();
+  this._firstTransition = false;
+  console.timeEnd('_doLayout');
+}
+
+D3SymbolTreeMap.prototype._highlightElement = function(datum, selection) {
+  this._showHighlight(datum, selection);
+}
+
+D3SymbolTreeMap.prototype._unhighlightElement = function(datum, selection) {
+  this._hideHighlight(datum, selection);
+}
+
+D3SymbolTreeMap.prototype._handleInodes = function() {
+  console.time('_handleInodes');
+  var thisTreeMap = this;
+  var inodes = this._currentNodes.filter(function(datum){
+    return (datum.depth <= thisTreeMap._currentMaxDepth) &&
+            datum.children !== undefined;
+  });
+  var cellsEnter = this._mapContainer.selectAll('div.inode')
+      .data(inodes, function(datum) { return datum.id; })
+      .enter()
+      .append('div').attr('class', 'inode').attr('id', function(datum){
+          return 'node-' + datum.id;});
+
+
+  // Define enter/update/exit for inodes
+  cellsEnter
+      .append('div')
+      .attr('class', 'rect inode_rect_entering')
+      .style('z-index', function(datum) { return datum.id * 2; })
+      .style('position', 'absolute')
+      .style('left', function(datum) { return datum.x; })
+      .style('top', function(datum){ return datum.y; })
+      .style('width', function(datum){ return datum.dx; })
+      .style('height', function(datum){ return datum.dy; })
+      .style('opacity', '0')
+      .style('border', '1px solid black')
+      .style('background-image', function(datum) {
+        return thisTreeMap._makeSymbolBucketBackgroundImage.call(
+               thisTreeMap, datum);
+      })
+      .style('background-color', function(datum) {
+        if (datum.t === undefined) return 'rgb(220,220,220)';
+        return D3SymbolTreeMap.getColorForType(datum.t).toString();
+      })
+      .on('mouseover', function(datum){
+        thisTreeMap._highlightElement.call(
+            thisTreeMap, datum, d3.select(this));
+        thisTreeMap._showInfoBox.call(thisTreeMap, datum);
+      })
+      .on('mouseout', function(datum){
+        thisTreeMap._unhighlightElement.call(
+            thisTreeMap, datum, d3.select(this));
+        thisTreeMap._hideInfoBox.call(thisTreeMap, datum);
+      })
+      .on('mousemove', function(){
+          thisTreeMap._moveInfoBox.call(thisTreeMap, event);
+      })
+      .on('dblclick', function(datum){
+        if (datum !== thisTreeMap._currentRoot) {
+          // Zoom into the selection
+          thisTreeMap._zoomDatum(datum);
+        } else if (datum.parent) {
+          console.log('event.shiftKey=' + event.shiftKey);
+          if (event.shiftKey === true) {
+            // Back to root
+            thisTreeMap._zoomDatum(thisTreeMap._treeData);
+          } else {
+            // Zoom out of the selection
+            thisTreeMap._zoomDatum(datum.parent);
+          }
+        }
+      });
+  cellsEnter
+      .append('div')
+      .attr('class', 'label inode_label_entering')
+      .style('z-index', function(datum) { return (datum.id * 2) + 1; })
+      .style('position', 'absolute')
+      .style('left', function(datum){ return datum.x; })
+      .style('top', function(datum){ return datum.y; })
+      .style('width', function(datum) { return datum.dx; })
+      .style('height', function(datum) { return thisTreeMap.boxPadding.t; })
+      .style('opacity', '0')
+      .style('pointer-events', 'none')
+      .style('-webkit-user-select', 'none')
+      .style('overflow', 'hidden') // required for ellipsis
+      .style('white-space', 'nowrap') // required for ellipsis
+      .style('text-overflow', 'ellipsis')
+      .style('text-align', 'center')
+      .style('vertical-align', 'top')
+      .style('visibility', function(datum) {
+        return (datum.dx < 15 || datum.dy < 15) ? 'hidden' : 'visible';
+      })
+      .text(function(datum) {
+        var sizeish = ' [' + D3SymbolTreeMap._byteify(datum.value) + ']'
+        var text;
+        if (datum.k === 'b') { // bucket
+          if (datum === thisTreeMap._currentRoot) {
+            text = thisTreeMap.pathFor(datum) + ': '
+                + D3SymbolTreeMap._getSymbolDescription(datum.t)
+          } else {
+            text = D3SymbolTreeMap._getSymbolDescription(datum.t);
+          }
+        } else if (datum === thisTreeMap._currentRoot) {
+          // The top-most level should always show the complete path
+          text = thisTreeMap.pathFor(datum);
+        } else {
+          // Anything that isn't a bucket or a leaf (symbol) or the
+          // current root should just show its name.
+          text = datum.n;
+        }
+        return text + sizeish;
+      }
+  );
+
+  // Complicated transition logic:
+  // For nodes that are entering, we want to fade them in in-place AFTER
+  // any adjusting nodes have resized and moved around. That way, new nodes
+  // seamlessly appear in the right spot after their containers have resized
+  // and moved around.
+  // To do this we do some trickery:
+  // 1. Define a '_entering' class on the entering elements
+  // 2. Use this to select only the entering elements and apply the opacity
+  //    transition.
+  // 3. Use the same transition to drop the '_entering' suffix, so that they
+  //    will correctly update in later zoom/resize/whatever operations.
+  // 4. The update transition is achieved by selecting the elements without
+  //    the '_entering_' suffix and applying movement and resizing transition
+  //    effects.
+  this._mapContainer.selectAll('div.inode_rect_entering').transition()
+      .duration(thisTreeMap._enterDuration).delay(
+          this._firstTransition ? 0 : thisTreeMap._exitDuration +
+              thisTreeMap._updateDuration)
+      .attr('class', 'rect inode_rect')
+      .style('opacity', '1')
+  this._mapContainer.selectAll('div.inode_label_entering').transition()
+      .duration(thisTreeMap._enterDuration).delay(
+          this._firstTransition ? 0 : thisTreeMap._exitDuration +
+              thisTreeMap._updateDuration)
+      .attr('class', 'label inode_label')
+      .style('opacity', '1')
+  this._mapContainer.selectAll('div.inode_rect').transition()
+      .duration(thisTreeMap._updateDuration).delay(thisTreeMap._exitDuration)
+      .style('opacity', '1')
+      .style('background-image', function(datum) {
+        return thisTreeMap._makeSymbolBucketBackgroundImage.call(
+            thisTreeMap, datum);
+      })
+      .style('left', function(datum) { return datum.x; })
+      .style('top', function(datum){ return datum.y; })
+      .style('width', function(datum){ return datum.dx; })
+      .style('height', function(datum){ return datum.dy; });
+  this._mapContainer.selectAll('div.inode_label').transition()
+      .duration(thisTreeMap._updateDuration).delay(thisTreeMap._exitDuration)
+      .style('opacity', '1')
+      .style('visibility', function(datum) {
+        return (datum.dx < 15 || datum.dy < 15) ? 'hidden' : 'visible';
+      })
+      .style('left', function(datum){ return datum.x; })
+      .style('top', function(datum){ return datum.y; })
+      .style('width', function(datum) { return datum.dx; })
+      .style('height', function(datum) { return thisTreeMap.boxPadding.t; })
+      .text(function(datum) {
+        var sizeish = ' [' + D3SymbolTreeMap._byteify(datum.value) + ']'
+        var text;
+        if (datum.k === 'b') {
+          if (datum === thisTreeMap._currentRoot) {
+            text = thisTreeMap.pathFor(datum) + ': ' +
+                D3SymbolTreeMap._getSymbolDescription(datum.t)
+          } else {
+            text = D3SymbolTreeMap._getSymbolDescription(datum.t);
+          }
+        } else if (datum === thisTreeMap._currentRoot) {
+          // The top-most level should always show the complete path
+          text = thisTreeMap.pathFor(datum);
+        } else {
+          // Anything that isn't a bucket or a leaf (symbol) or the
+          // current root should just show its name.
+          text = datum.n;
+        }
+        return text + sizeish;
+      });
+  var exit = this._mapContainer.selectAll('div.inode')
+      .data(inodes, function(datum) { return 'inode-' + datum.id; })
+      .exit();
+  exit.selectAll('div.inode_rect').transition().duration(
+      thisTreeMap._exitDuration).style('opacity', 0);
+  exit.selectAll('div.inode_label').transition().duration(
+      thisTreeMap._exitDuration).style('opacity', 0);
+  exit.transition().delay(thisTreeMap._exitDuration + 1).remove();
+
+  console.log(inodes.length + ' inodes layed out.');
+  console.timeEnd('_handleInodes');
+}
+
+D3SymbolTreeMap.prototype._handleLeaves = function() {
+  console.time('_handleLeaves');
+  var color_fn = d3.scale.category10();
+  var thisTreeMap = this;
+  var leaves = this._currentNodes.filter(function(datum){
+    return (datum.depth <= thisTreeMap._currentMaxDepth) &&
+        datum.children === undefined; });
+  var cellsEnter = this._mapContainer.selectAll('div.leaf')
+      .data(leaves, function(datum) { return datum.id; })
+      .enter()
+      .append('div').attr('class', 'leaf').attr('id', function(datum){
+        return 'node-' + datum.id;
+      });
+
+  // Define enter/update/exit for leaves
+  cellsEnter
+      .append('div')
+      .attr('class', 'rect leaf_rect_entering')
+      .style('z-index', function(datum) { return datum.id * 2; })
+      .style('position', 'absolute')
+      .style('left', function(datum){ return datum.x; })
+      .style('top', function(datum){ return datum.y; })
+      .style('width', function(datum){ return datum.dx; })
+      .style('height', function(datum){ return datum.dy; })
+      .style('opacity', '0')
+      .style('background-color', function(datum) {
+        if (datum.t === undefined) return 'rgb(220,220,220)';
+        return D3SymbolTreeMap.getColorForType(datum.t)
+            .darker(0.3).toString();
+      })
+      .style('border', '1px solid black')
+      .on('mouseover', function(datum){
+        thisTreeMap._highlightElement.call(
+            thisTreeMap, datum, d3.select(this));
+        thisTreeMap._showInfoBox.call(thisTreeMap, datum);
+      })
+      .on('mouseout', function(datum){
+        thisTreeMap._unhighlightElement.call(
+            thisTreeMap, datum, d3.select(this));
+        thisTreeMap._hideInfoBox.call(thisTreeMap, datum);
+      })
+      .on('mousemove', function(){ thisTreeMap._moveInfoBox.call(
+        thisTreeMap, event);
+      });
+  cellsEnter
+      .append('div')
+      .attr('class', 'label leaf_label_entering')
+      .style('z-index', function(datum) { return (datum.id * 2) + 1; })
+      .style('position', 'absolute')
+      .style('left', function(datum){ return datum.x; })
+      .style('top', function(datum){ return datum.y; })
+      .style('width', function(datum) { return datum.dx; })
+      .style('height', function(datum) { return datum.dy; })
+      .style('opacity', '0')
+      .style('pointer-events', 'none')
+      .style('-webkit-user-select', 'none')
+      .style('overflow', 'hidden') // required for ellipsis
+      .style('white-space', 'nowrap') // required for ellipsis
+      .style('text-overflow', 'ellipsis')
+      .style('text-align', 'center')
+      .style('vertical-align', 'middle')
+      .style('visibility', function(datum) {
+        return (datum.dx < 15 || datum.dy < 15) ? 'hidden' : 'visible';
+      })
+      .text(function(datum) { return datum.n; });
+
+  // Complicated transition logic: See note in _handleInodes()
+  this._mapContainer.selectAll('div.leaf_rect_entering').transition()
+      .duration(thisTreeMap._enterDuration).delay(
+          this._firstTransition ? 0 : thisTreeMap._exitDuration +
+              thisTreeMap._updateDuration)
+      .attr('class', 'rect leaf_rect')
+      .style('opacity', '1')
+  this._mapContainer.selectAll('div.leaf_label_entering').transition()
+      .duration(thisTreeMap._enterDuration).delay(
+          this._firstTransition ? 0 : thisTreeMap._exitDuration +
+              thisTreeMap._updateDuration)
+      .attr('class', 'label leaf_label')
+      .style('opacity', '1')
+  this._mapContainer.selectAll('div.leaf_rect').transition()
+      .duration(thisTreeMap._updateDuration).delay(thisTreeMap._exitDuration)
+      .style('opacity', '1')
+      .style('left', function(datum){ return datum.x; })
+      .style('top', function(datum){ return datum.y; })
+      .style('width', function(datum){ return datum.dx; })
+      .style('height', function(datum){ return datum.dy; });
+  this._mapContainer.selectAll('div.leaf_label').transition()
+      .duration(thisTreeMap._updateDuration).delay(thisTreeMap._exitDuration)
+      .style('opacity', '1')
+      .style('visibility', function(datum) {
+          return (datum.dx < 15 || datum.dy < 15) ? 'hidden' : 'visible';
+      })
+      .style('left', function(datum){ return datum.x; })
+      .style('top', function(datum){ return datum.y; })
+      .style('width', function(datum) { return datum.dx; })
+      .style('height', function(datum) { return datum.dy; });
+  var exit = this._mapContainer.selectAll('div.leaf')
+      .data(leaves, function(datum) { return 'leaf-' + datum.id; })
+      .exit();
+  exit.selectAll('div.leaf_rect').transition()
+      .duration(thisTreeMap._exitDuration)
+      .style('opacity', 0);
+  exit.selectAll('div.leaf_label').transition()
+      .duration(thisTreeMap._exitDuration)
+      .style('opacity', 0);
+  exit.transition().delay(thisTreeMap._exitDuration + 1).remove();
+
+  console.log(leaves.length + ' leaves layed out.');
+  console.timeEnd('_handleLeaves');
+}
+
+D3SymbolTreeMap.prototype._makeSymbolBucketBackgroundImage = function(datum) {
+  if (!(datum.t === undefined && datum.depth == this._currentMaxDepth)) {
+    return 'none';
+  }
+  var text = '';
+  var lastStop = 0;
+  for (var x = 0; x < D3SymbolTreeMap._NM_SYMBOL_TYPES.length; x++) {
+    symbol_type = D3SymbolTreeMap._NM_SYMBOL_TYPES.charAt(x);
+    var stats = datum.symbol_stats[symbol_type];
+    if (stats !== undefined) {
+      if (text.length !== 0) {
+        text += ', ';
+      }
+      var percent = 100 * (stats.size / datum.value);
+      var nowStop = lastStop + percent;
+      var tempcolor = D3SymbolTreeMap.getColorForType(symbol_type);
+      var color = d3.rgb(tempcolor).toString();
+      text += color + ' ' + lastStop + '%, ' + color + ' ' +
+          nowStop + '%';
+      lastStop = nowStop;
+    }
+  }
+  return 'linear-gradient(' + (datum.dx > datum.dy ? 'to right' :
+                               'to bottom') + ', ' + text + ')';
+}
+
+D3SymbolTreeMap.prototype.pathFor = function(datum) {
+  if (datum.__path) return datum.__path;
+  parts=[];
+  node = datum;
+  while (node) {
+    if (node.k === 'p') { // path node
+      if(node.n !== '/') parts.unshift(node.n);
+    }
+    node = node.parent;
+  }
+  datum.__path = '/' + parts.join('/');
+  return datum.__path;
+}
+
+D3SymbolTreeMap.prototype._createHighlight = function(datum, selection) {
+  var x = parseInt(selection.style('left'));
+  var y = parseInt(selection.style('top'));
+  var w = parseInt(selection.style('width'));
+  var h = parseInt(selection.style('height'));
+  datum.highlight = this._mapContainer.append('div')
+      .attr('id', 'h-' + datum.id)
+      .attr('class', 'highlight')
+      .style('pointer-events', 'none')
+      .style('-webkit-user-select', 'none')
+      .style('z-index', '999999')
+      .style('position', 'absolute')
+      .style('top', y-2)
+      .style('left', x-2)
+      .style('width', w+4)
+      .style('height', h+4)
+      .style('margin', 0)
+      .style('padding', 0)
+      .style('border', '4px outset rgba(250,40,200,0.9)')
+      .style('box-sizing', 'border-box')
+      .style('opacity', 0.0);
+}
+
+D3SymbolTreeMap.prototype._showHighlight = function(datum, selection) {
+  if (datum === this._currentRoot) return;
+  if (datum.highlight === undefined) {
+    this._createHighlight(datum, selection);
+  }
+  datum.highlight.transition().duration(200).style('opacity', 1.0);
+}
+
+D3SymbolTreeMap.prototype._hideHighlight = function(datum, selection) {
+  if (datum.highlight === undefined) return;
+  datum.highlight.transition().duration(750)
+      .style('opacity', 0)
+      .each('end', function(){
+        if (datum.highlight) datum.highlight.remove();
+        delete datum.highlight;
+      });
+}
+
+D3SymbolTreeMap.prototype._createInfoBox = function() {
+  return d3.select('body')
+      .append('div')
+      .attr('id', 'infobox')
+      .style('z-index', '2147483647') // (2^31) - 1: Hopefully safe :)
+      .style('position', 'absolute')
+      .style('visibility', 'hidden')
+      .style('background-color', 'rgba(255,255,255, 0.9)')
+      .style('border', '1px solid black')
+      .style('padding', '10px')
+      .style('-webkit-user-select', 'none')
+      .style('box-shadow', '3px 3px rgba(70,70,70,0.5)')
+      .style('border-radius', '10px')
+      .style('white-space', 'nowrap');
+}
+
+D3SymbolTreeMap.prototype._showInfoBox = function(datum) {
+  this.infobox.text('');
+  var numSymbols = 0;
+  var sizeish = D3SymbolTreeMap._pretty(datum.value) + ' bytes (' +
+      D3SymbolTreeMap._byteify(datum.value) + ')';
+  if (datum.k === 'p' || datum.k === 'b') { // path or bucket
+    if (datum.symbol_stats) { // can be empty if filters are applied
+      for (var x = 0; x < D3SymbolTreeMap._NM_SYMBOL_TYPES.length; x++) {
+        symbol_type = D3SymbolTreeMap._NM_SYMBOL_TYPES.charAt(x);
+        var stats = datum.symbol_stats[symbol_type];
+        if (stats !== undefined) numSymbols += stats.count;
+      }
+    }
+  } else if (datum.k === 's') { // symbol
+    numSymbols = 1;
+  }
+
+  if (datum.k === 'p' && !datum.lastPathElement) {
+    this.infobox.append('div').text('Directory: ' + this.pathFor(datum))
+    this.infobox.append('div').text('Size: ' + sizeish);
+  } else {
+    if (datum.k === 'p') { // path
+      this.infobox.append('div').text('File: ' + this.pathFor(datum))
+      this.infobox.append('div').text('Size: ' + sizeish);
+    } else if (datum.k === 'b') { // bucket
+      this.infobox.append('div').text('Symbol Bucket: ' +
+          D3SymbolTreeMap._getSymbolDescription(datum.t));
+      this.infobox.append('div').text('Count: ' + numSymbols);
+      this.infobox.append('div').text('Size: ' + sizeish);
+      this.infobox.append('div').text('Location: ' + this.pathFor(datum))
+    } else if (datum.k === 's') { // symbol
+      this.infobox.append('div').text('Symbol: ' + datum.n);
+      this.infobox.append('div').text('Type: ' +
+          D3SymbolTreeMap._getSymbolDescription(datum.t));
+      this.infobox.append('div').text('Size: ' + sizeish);
+      this.infobox.append('div').text('Location: ' + this.pathFor(datum))
+    }
+  }
+  if (datum.k === 'p') {
+    this.infobox.append('div')
+        .text('Number of symbols: ' + D3SymbolTreeMap._pretty(numSymbols));
+    if (datum.symbol_stats) { // can be empty if filters are applied
+      var table = this.infobox.append('table')
+          .attr('border', 1).append('tbody');
+      var header = table.append('tr');
+      header.append('th').text('Type');
+      header.append('th').text('Count');
+      header.append('th')
+          .style('white-space', 'nowrap')
+          .text('Total Size (Bytes)');
+      for (var x = 0; x < D3SymbolTreeMap._NM_SYMBOL_TYPES.length; x++) {
+        symbol_type = D3SymbolTreeMap._NM_SYMBOL_TYPES.charAt(x);
+        var stats = datum.symbol_stats[symbol_type];
+        if (stats !== undefined) {
+          var tr = table.append('tr');
+          tr.append('td')
+              .style('white-space', 'nowrap')
+              .text(D3SymbolTreeMap._getSymbolDescription(
+                  symbol_type));
+          tr.append('td').text(D3SymbolTreeMap._pretty(stats.count));
+          tr.append('td').text(D3SymbolTreeMap._pretty(stats.size));
+        }
+      }
+    }
+  }
+  this.infobox.style('visibility', 'visible');
+}
+
+D3SymbolTreeMap.prototype._hideInfoBox = function(datum) {
+  this.infobox.style('visibility', 'hidden');
+}
+
+D3SymbolTreeMap.prototype._moveInfoBox = function(event) {
+  var element = document.getElementById('infobox');
+  var w = element.offsetWidth;
+  var h = element.offsetHeight;
+  var offsetLeft = 10;
+  var offsetTop = 10;
+
+  var rightLimit = window.innerWidth;
+  var rightEdge = event.pageX + offsetLeft + w;
+  if (rightEdge > rightLimit) {
+    // Too close to screen edge, reflect around the cursor
+    offsetLeft = -1 * (w + offsetLeft);
+  }
+
+  var bottomLimit = window.innerHeight;
+  var bottomEdge = event.pageY + offsetTop + h;
+  if (bottomEdge > bottomLimit) {
+    // Too close ot screen edge, reflect around the cursor
+    offsetTop = -1 * (h + offsetTop);
+  }
+
+  this.infobox.style('top', (event.pageY + offsetTop) + 'px')
+      .style('left', (event.pageX + offsetLeft) + 'px');
+}
+
+D3SymbolTreeMap.prototype.biggestSymbols = function(maxRecords) {
+  var result = undefined;
+  var smallest = undefined;
+  var sortFunction = function(a,b) {
+    var result = b.value - a.value;
+    if (result !== 0) return result; // sort by size
+    var pathA = treemap.pathFor(a); // sort by path
+    var pathB = treemap.pathFor(b);
+    if (pathA > pathB) return 1;
+    if (pathB > pathA) return -1;
+    return a.n - b.n; // sort by symbol name
+  };
+  this.visitFromDisplayedRoot(function(datum) {
+    if (datum.children) return; // ignore non-leaves
+    if (!result) { // first element
+      result = [datum];
+      smallest = datum.value;
+      return;
+    }
+    if (result.length < maxRecords) { // filling the array
+      result.push(datum);
+      return;
+    }
+    if (datum.value > smallest) { // array is already full
+      result.push(datum);
+      result.sort(sortFunction);
+      result.pop(); // get rid of smallest element
+      smallest = result[maxRecords - 1].value; // new threshold for entry
+    }
+  });
+  result.sort(sortFunction);
+  return result;
+}
+
+D3SymbolTreeMap.prototype.biggestPaths = function(maxRecords) {
+  var result = undefined;
+  var smallest = undefined;
+  var sortFunction = function(a,b) {
+    var result = b.value - a.value;
+    if (result !== 0) return result; // sort by size
+    var pathA = treemap.pathFor(a); // sort by path
+    var pathB = treemap.pathFor(b);
+    if (pathA > pathB) return 1;
+    if (pathB > pathA) return -1;
+    console.log('warning, multiple entries for the same path: ' + pathA);
+    return 0; // should be impossible
+  };
+  this.visitFromDisplayedRoot(function(datum) {
+    if (!datum.lastPathElement) return; // ignore non-files
+    if (!result) { // first element
+      result = [datum];
+      smallest = datum.value;
+      return;
+    }
+    if (result.length < maxRecords) { // filling the array
+      result.push(datum);
+      return;
+    }
+    if (datum.value > smallest) { // array is already full
+      result.push(datum);
+      result.sort(sortFunction);
+      result.pop(); // get rid of smallest element
+      smallest = result[maxRecords - 1].value; // new threshold for entry
+    }
+  });
+  result.sort(sortFunction);
+  return result;
+}