Let the viewer collapse/expand individual files in a diff.

Summary:
Added a dropdown menu button and the keyboard shortcut 'h' to the
web diff view. These hide or show the annotated code display.

Test Plan:
Viewed an example diff that changed a large number of source files
and played around with keyboard shortcuts. Everything seemed to
work as expected.

Reviewers: nh, epriestley

Reviewed By: epriestley

CC: aran, epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D2714

src/applications/differential/view/DifferentialChangesetListView.php

@@ -112,6 +112,8 @@ final class DifferentialChangesetListView extends AphrontView {
 
     Javelin::initBehavior('buoyant', array());
 
+    Javelin::initBehavior('differential-toggle-files', array());
+
     $output = array();
     $mapping = array();
     foreach ($changesets as $key => $changeset) {

webroot/rsrc/js/application/differential/behavior-comment-jump.js

@@ -19,6 +19,9 @@ JX.behavior('differential-comment-jump', function(config) {
           break;
         }
       }
+      JX.Stratcom.invoke('differential-toggle-file-request', null, {
+        element: jumpto,
+      });
       JX.DOM.scrollTo(jumpto);
       e.kill();
     });

webroot/rsrc/js/application/differential/behavior-dropdown-menus.js

@@ -52,6 +52,13 @@ JX.behavior('differential-dropdown-menus', function(config) {
     var menu = new JX.PhabricatorDropdownMenu(buttons[ii])
       .addItem(reveal_item);
 
+    var visible_item = new JX.PhabricatorMenuItem('', function () {
+      JX.Stratcom.invoke('differential-toggle-file', null, {
+        diff: JX.DOM.scry(JX.$(data.containerID), 'table', 'differential-diff'),
+      });
+    });
+    menu.addItem(visible_item);
+
     if (diffusion_item) {
       menu.addItem(diffusion_item);
     }
@@ -93,6 +100,14 @@ JX.behavior('differential-dropdown-menus', function(config) {
           reveal_item.setDisabled(true);
           reveal_item.setName('Entire File Shown');
         }
+
+        var diff = JX.DOM.find(JX.$(data.containerID),
+                               'table', 'differential-diff');
+        if (JX.Stratcom.getData(diff).hidden) {
+          visible_item.setName('Expand File');
+        } else {
+          visible_item.setName('Collapse File');
+        }
       });
   }
 

webroot/rsrc/js/application/differential/behavior-keyboard-nav.js

@@ -14,6 +14,8 @@ JX.behavior('differential-keyboard-navigation', function(config) {
   var selection_begin = null;
   var selection_end = null;
 
+  var refreshFocus = function() {};
+
   function init() {
     if (changesets) {
       return;
@@ -31,6 +33,12 @@ JX.behavior('differential-keyboard-navigation', function(config) {
     var type;
     var ii;
 
+    // Don't show code blocks inside a collapsed file.
+    var diff = JX.DOM.scry(changesets[cursor], 'table', 'differential-diff');
+    if (diff.length == 1 && JX.Stratcom.getData(diff[0]).hidden) {
+      return blocks;
+    }
+
     function push() {
       if (start) {
         blocks.push([start, rows[ii - 1]]);
@@ -122,7 +130,9 @@ JX.behavior('differential-keyboard-navigation', function(config) {
           selection_end = blocks[focus][1];
 
           manager.scrollTo(selection_begin);
-          manager.focusOn(selection_begin, selection_end);
+          (refreshFocus = function() {
+            manager.focusOn(selection_begin, selection_end);
+          })();
 
           return;
         } else {
@@ -149,6 +159,16 @@ JX.behavior('differential-keyboard-navigation', function(config) {
     function() {
       changesets = null;
     });
+  // Same thing when a file is hidden or shown; don't want to highlight
+  // invisible code.
+  JX.Stratcom.listen(
+    'differential-toggle-file-toggled',
+    null,
+    function() {
+      changesets = null;
+      init();
+      refreshFocus();
+    });
 
   var haunt_mode = 0;
   function haunt() {
@@ -205,6 +225,18 @@ JX.behavior('differential-keyboard-navigation', function(config) {
     .register();
 
 
+  new JX.KeyboardShortcut('h', 'Collapse or expand the file display.')
+    .setHandler(function(manager) {
+      if (!changesets || !changesets[cursor]) {
+        return;
+      }
+      JX.Stratcom.invoke('differential-toggle-file', null, {
+        diff: JX.DOM.scry(changesets[cursor], 'table', 'differential-diff'),
+      });
+    })
+    .register();
+
+
   function inline_op(node, op) {
     if (!JX.DOM.scry(node, 'a', 'differential-inline-' + op)) {
       // No link for this operation, e.g. editing a comment you can't edit.

webroot/rsrc/js/application/differential/behavior-toggle-files.js

@@ -0,0 +1,62 @@
+/**
+ * @provides javelin-behavior-differential-toggle-files
+ * @requires javelin-behavior
+ *           javelin-dom
+ *           javelin-stratcom
+ *           phabricator-keyboard-shortcut
+ */
+
+JX.behavior('differential-toggle-files', function(config) {
+
+  JX.Stratcom.listen(
+    'differential-toggle-file',
+    null,
+    function(e) {
+      if (e.getData().diff.length != 1) {
+        return;
+      }
+      var diff = e.getData().diff[0],
+          data = JX.Stratcom.getData(diff);
+      if(data.hidden) {
+        data.hidden = false;
+        JX.DOM.show(diff);
+      } else {
+        data.hidden = true;
+        JX.DOM.hide(diff);
+      }
+      JX.Stratcom.invoke('differential-toggle-file-toggled');
+    });
+
+  JX.Stratcom.listen(
+    'differential-toggle-file-request',
+    null,
+    function(e) {
+      var elt = e.getData().element;
+      while (elt !== document.body) {
+        if (JX.Stratcom.hasSigil(elt, 'differential-diff') &&
+            JX.Stratcom.getData(elt).hidden) {
+          JX.Stratcom.invoke('differential-toggle-file', null, {
+            diff: [ elt ],
+          });
+          return;
+        }
+        elt = elt.parentNode;
+      }
+    });
+
+  JX.Stratcom.listen(
+    'hashchange',
+    null,
+    function(e) {
+      var id = window.location.hash;
+      if (!id.match(/^#/)) {
+        return;
+      }
+      JX.Stratcom.invoke('differential-toggle-file-request', null, {
+        element: JX.$(id.substr(1)),
+      });
+      // This event is processed after the hash has changed, so it doesn't
+      // automatically jump there like we want.
+      JX.DOM.scrollTo(JX.$(id.substr(1)));
+    });
+});