When a directory has a single directory child, collapse them into a single "a/b/" path entry

Summary:
Ref T13516. Instead of rendering trees like this:

  - a/
    - b/
      - c.txt

...render:

  - a/b/
    - c.txt

Test Plan: {F7374205}

Maniphest Tasks: T13516

Differential Revision: https://secure.phabricator.com/D21155

resources/celerity/map.php

@@ -59,7 +59,7 @@ return array(
     'rsrc/css/application/countdown/timer.css' => 'bff8012f',
     'rsrc/css/application/daemon/bulk-job.css' => '73af99f5',
     'rsrc/css/application/dashboard/dashboard.css' => '5a205b9d',
-    'rsrc/css/application/diff/diff-tree-view.css' => '8f487a99',
+    'rsrc/css/application/diff/diff-tree-view.css' => 'bd83417c',
     'rsrc/css/application/diff/inline-comment-summary.css' => '81eb368d',
     'rsrc/css/application/differential/add-comment.css' => '7e5900d9',
     'rsrc/css/application/differential/changeset-view.css' => '489b6995',
@@ -381,8 +381,8 @@ return array(
     'rsrc/js/application/diff/DiffChangeset.js' => '2a3101b1',
     'rsrc/js/application/diff/DiffChangesetList.js' => '57035863',
     'rsrc/js/application/diff/DiffInline.js' => '16e97ebc',
-    'rsrc/js/application/diff/DiffPathView.js' => 'c0ed32ce',
-    'rsrc/js/application/diff/DiffTreeView.js' => 'a5823e4d',
+    'rsrc/js/application/diff/DiffPathView.js' => '5f70ad12',
+    'rsrc/js/application/diff/DiffTreeView.js' => 'ccf691f3',
     'rsrc/js/application/diff/behavior-preview-link.js' => 'f51e9c17',
     'rsrc/js/application/differential/behavior-diff-radios.js' => '925fe8cd',
     'rsrc/js/application/differential/behavior-populate.js' => 'b86ef6c2',
@@ -558,7 +558,7 @@ return array(
     'conpherence-thread-manager' => 'aec8e38c',
     'conpherence-transaction-css' => '3a3f5e7e',
     'd3' => '9d068042',
-    'diff-tree-view-css' => '8f487a99',
+    'diff-tree-view-css' => 'bd83417c',
     'differential-changeset-view-css' => '489b6995',
     'differential-core-view-css' => '7300a73e',
     'differential-revision-add-comment-css' => '7e5900d9',
@@ -778,8 +778,8 @@ return array(
     'phabricator-diff-changeset' => '2a3101b1',
     'phabricator-diff-changeset-list' => '57035863',
     'phabricator-diff-inline' => '16e97ebc',
-    'phabricator-diff-path-view' => 'c0ed32ce',
-    'phabricator-diff-tree-view' => 'a5823e4d',
+    'phabricator-diff-path-view' => '5f70ad12',
+    'phabricator-diff-tree-view' => 'ccf691f3',
     'phabricator-drag-and-drop-file-upload' => '4370900d',
     'phabricator-draggable-list' => '0169e425',
     'phabricator-fatal-config-template-css' => '20babf50',
@@ -1517,6 +1517,9 @@ return array(
       'javelin-dom',
       'phuix-dropdown-menu',
     ),
+    '5f70ad12' => array(
+      'javelin-dom',
+    ),
     '5faf27b9' => array(
       'phuix-form-control-view',
     ),
@@ -1869,9 +1872,6 @@ return array(
       'javelin-install',
       'javelin-dom',
     ),
-    'a5823e4d' => array(
-      'javelin-dom',
-    ),
     'a9942052' => array(
       'javelin-behavior',
       'javelin-dom',
@@ -2035,9 +2035,6 @@ return array(
     'c03f2fb4' => array(
       'javelin-install',
     ),
-    'c0ed32ce' => array(
-      'javelin-dom',
-    ),
     'c2c500a7' => array(
       'javelin-install',
       'javelin-dom',
@@ -2082,6 +2079,9 @@ return array(
       'phuix-icon-view',
       'phabricator-busy',
     ),
+    'ccf691f3' => array(
+      'javelin-dom',
+    ),
     'cef53b3e' => array(
       'javelin-install',
       'javelin-dom',

webroot/rsrc/css/application/diff/diff-tree-view.css

@@ -8,8 +8,8 @@
 
 .diff-tree-path {
   height: 20px;
-  color: {$greytext};
   line-height: 20px;
+  color: {$greytext};
 }
 
 .diff-tree-path-indent {
@@ -23,8 +23,12 @@
   text-align: center;
 }
 
+.diff-tree-path-icon .phui-icon-view {
+  color: {$greytext};
+}
+
 .diff-tree-path-name {
-  margin-left: 24px;
+  margin-left: 22px;
   margin-right: 44px;
   white-space: nowrap;
   overflow: hidden;

webroot/rsrc/js/application/diff/DiffPathView.js

@@ -21,6 +21,8 @@ JX.install('DiffPathView', {
     _pathNode: null,
     _changeset: null,
     _inlineNode: null,
+    _isDirectory: false,
+    _displayPath: null,
 
     getNode: function() {
       if (!this._node) {
@@ -45,10 +47,19 @@ JX.install('DiffPathView', {
 
     setPath: function(path) {
       this._path = path;
+      this._redrawPath();
+      return this;
+    },
 
-      var display = this._path[this._path.length - 1];
-      JX.DOM.setContent(this._getPathNode(), display);
+    setDisplayPath: function(path) {
+      this._displayPath = path;
+      this._redrawPath();
+      return this;
+    },
 
+    setIsDirectory: function(is_directory) {
+      this._isDirectory = is_directory;
+      this._redrawPath();
       return this;
     },
 
@@ -69,10 +80,23 @@ JX.install('DiffPathView', {
       return this._path;
     },
 
+    setHidden: function(hidden) {
+      this._hidden = hidden;
+
+      var node = this.getNode();
+      if (this._hidden) {
+        JX.DOM.hide(node);
+      } else {
+        JX.DOM.show(node);
+      }
+
+      return this;
+    },
+
     setDepth: function(depth) {
       this._depth = depth;
 
-      this._getIndentNode().style.marginLeft = (6 * this._depth) + 'px';
+      this._getIndentNode().style.marginLeft = (8 * this._depth) + 'px';
 
       return this;
     },
@@ -154,6 +178,23 @@ JX.install('DiffPathView', {
         this._inlineNode = JX.$N('div', attrs, '-');
       }
       return this._inlineNode;
+    },
+
+    _redrawPath: function() {
+      var display;
+      if (this._displayPath) {
+        display = this._displayPath;
+      } else {
+        display = this._path[this._path.length - 1];
+      }
+
+      var is_directory = this._isDirectory;
+
+      if (is_directory) {
+        display = display + '/';
+      }
+
+      JX.DOM.setContent(this._getPathNode(), display);
     }
 
   }

webroot/rsrc/js/application/diff/DiffTreeView.js

@@ -94,11 +94,12 @@ JX.install('DiffTreeView', {
 
       // For nodes which don't have a path object yet, build one.
       var tree;
+      var path;
       var trees = [];
       for (ii = 0; ii < this._keys.length; ii++) {
         var key = this._keys[ii];
         tree = this._nodes[key];
-        var path = tree.pathObject;
+        path = tree.pathObject;
 
         if (!path) {
           path = new JX.DiffPathView()
@@ -113,16 +114,87 @@ JX.install('DiffTreeView', {
         trees.push(tree);
       }
 
+      for (ii = 0; ii < trees.length; ii++) {
+        tree = trees[ii];
+        tree.displayRoot = null;
+        tree.displayPath = null;
+        tree.displayHide = false;
+      }
+
+      var child;
+      for (ii = 0; ii < trees.length; ii++) {
+        tree = trees[ii];
+
+        if (tree.childCount !== 1) {
+          continue;
+        }
+
+        for (var k in tree.children) {
+          if (tree.children.hasOwnProperty(k)) {
+            child = tree.children[k];
+            break;
+          }
+        }
+
+        if (child.pathObject.getChangeset()) {
+          continue;
+        }
+
+        child.displayRoot = tree.displayRoot || tree;
+      }
+
+      for (ii = 0; ii < trees.length; ii++) {
+        tree = trees[ii];
+
+        if (!tree.displayRoot) {
+          continue;
+        }
+
+        if (!tree.displayRoot.displayPath) {
+          tree.displayRoot.displayPath = [
+            tree.displayRoot.parts[tree.displayRoot.parts.length - 1]
+          ];
+        }
+
+        tree.displayRoot.displayPath.push(tree.parts[tree.parts.length - 1]);
+        tree.displayHide = true;
+      }
+
+      for (ii = 0; ii < trees.length; ii++) {
+        tree = trees[ii];
+        path = tree.pathObject;
+
+        path.setHidden(!!tree.displayHide);
+
+        if (tree.displayPath) {
+          path.setDisplayPath(tree.displayPath.join('/'));
+        } else {
+          path.setDisplayPath(null);
+        }
+      }
+
       for (ii = 0; ii < trees.length; ii++) {
         tree = trees[ii];
 
         if (!tree.parent) {
           tree.depth = 0;
         } else {
-          tree.depth = tree.parent.depth + 1;
+          // If this node was collapsed into the parent node, don't increase
+          // the tree depth.
+          if (tree.displayHide) {
+            tree.depth = tree.parent.depth;
+          } else {
+            tree.depth = tree.parent.depth + 1;
+          }
         }
 
-        tree.pathObject.setDepth((tree.depth - 1));
+        path = tree.pathObject;
+
+        if (tree.childCount > 0) {
+          path.setIsDirectory(true);
+        }
+
+        path.setDepth((tree.depth - 1));
       }
 
       var nodes = [];