From b8ed980d3dc53094832ba62a7083a30904b421da Mon Sep 17 00:00:00 2001
From: epriestley <git@epriestley.com>
Date: Sat, 7 Mar 2015 09:53:58 -0800
Subject: [PATCH] Fix scrollbar being cut off at end of gutter

Summary:
The "mlb" on the left nav creates a phantom bottom margin which gives the content measurable height but not scrollable height. Replace it with "plb" (padding) instead.

The 2px-spacer calculation was also not quite correct.

Test Plan:
  - Viewed pages with navs; padding vs margin didn't seem to make any other differences.
  - Scrollbar now stops in the right place in Safari, Chrome, Firefox.

Reviewers: btrahan, chad

Reviewed By: chad

Subscribers: epriestley

Differential Revision: https://secure.phabricator.com/D12007
---
 resources/celerity/map.php                      | 16 ++++++++--------
 src/view/layout/AphrontSideNavFilterView.php    |  2 +-
 webroot/rsrc/externals/javelin/lib/Scrollbar.js |  9 +++++++--
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/resources/celerity/map.php b/resources/celerity/map.php
index 1ca906f60d..250f4ce3c7 100644
--- a/resources/celerity/map.php
+++ b/resources/celerity/map.php
@@ -207,7 +207,7 @@ return array(
     'rsrc/externals/javelin/lib/Resource.js' => '44959b73',
     'rsrc/externals/javelin/lib/Routable.js' => 'b3e7d692',
     'rsrc/externals/javelin/lib/Router.js' => '29274e2b',
-    'rsrc/externals/javelin/lib/Scrollbar.js' => '5b2f5a08',
+    'rsrc/externals/javelin/lib/Scrollbar.js' => '1ed54a27',
     'rsrc/externals/javelin/lib/URI.js' => '6eff08aa',
     'rsrc/externals/javelin/lib/Vector.js' => '2caa8fb8',
     'rsrc/externals/javelin/lib/WebSocket.js' => 'e292eaf4',
@@ -676,7 +676,7 @@ return array(
     'javelin-resource' => '44959b73',
     'javelin-routable' => 'b3e7d692',
     'javelin-router' => '29274e2b',
-    'javelin-scrollbar' => '5b2f5a08',
+    'javelin-scrollbar' => '1ed54a27',
     'javelin-stratcom' => '6c53634d',
     'javelin-tokenizer' => '7644823e',
     'javelin-typeahead' => '70baed2f',
@@ -942,6 +942,12 @@ return array(
       'javelin-dom',
       'javelin-reactor-dom',
     ),
+    '1ed54a27' => array(
+      'javelin-install',
+      'javelin-dom',
+      'javelin-stratcom',
+      'javelin-vector',
+    ),
     '2035b9cb' => array(
       'javelin-behavior',
       'javelin-dom',
@@ -1175,12 +1181,6 @@ return array(
       'javelin-vector',
       'javelin-dom',
     ),
-    '5b2f5a08' => array(
-      'javelin-install',
-      'javelin-dom',
-      'javelin-stratcom',
-      'javelin-vector',
-    ),
     '5bc2cb21' => array(
       'javelin-behavior',
       'javelin-stratcom',
diff --git a/src/view/layout/AphrontSideNavFilterView.php b/src/view/layout/AphrontSideNavFilterView.php
index 29f1d649ad..4f4c0803b8 100644
--- a/src/view/layout/AphrontSideNavFilterView.php
+++ b/src/view/layout/AphrontSideNavFilterView.php
@@ -318,7 +318,7 @@ final class AphrontSideNavFilterView extends AphrontView {
         phutil_tag(
           'div',
           array(
-            'class' => 'phabricator-nav-content mlb',
+            'class' => 'phabricator-nav-content plb',
             'id' => $content_id,
           ),
           array(
diff --git a/webroot/rsrc/externals/javelin/lib/Scrollbar.js b/webroot/rsrc/externals/javelin/lib/Scrollbar.js
index 2242e048b6..6f52811619 100644
--- a/webroot/rsrc/externals/javelin/lib/Scrollbar.js
+++ b/webroot/rsrc/externals/javelin/lib/Scrollbar.js
@@ -320,10 +320,15 @@ JX.install('Scrollbar', {
       var spos = JX.Vector.getAggregateScrollForNode(this._viewport);
       var vdim = JX.Vector.getDim(this._viewport);
 
-      var ratio = vdim.y / cdim.y;
+      var ratio = (vdim.y / cdim.y);
+
+      // We're scaling things down very slightly to leave a 2px margin at
+      // either end of the scroll gutter, so the bar doesn't quite bump up
+      // against the chrome.
+      ratio = ratio * (vdim.y / (vdim.y + 4));
 
       var offset = Math.round(ratio * spos.y) + 2;
-      var size = Math.floor(ratio * (vdim.y - 2)) - 2;
+      var size = Math.floor(ratio * vdim.y);
 
       if (size < cdim.y) {
         this._handle.style.top = offset + 'px';