From c504b10e4a0a4c08e05bd1a2aeb641d2fb58e8b2 Mon Sep 17 00:00:00 2001
From: Dung Le <dungleviethoang@gmail.com>
Date: Tue, 24 Sep 2019 12:56:44 +0700
Subject: [PATCH] Fix scroll bars not appearing on certain settings

Setting the bounds origins directly caused the scroll bar to not show up due to scroller management being hidden in `scroll(to: )`. This commit fixes that by canceling the animation after the call instead.
---
 Sources/XiEditor/EditViewController.swift | 3 +++
 Sources/XiEditor/XiClipView.swift         | 7 +------
 2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/Sources/XiEditor/EditViewController.swift b/Sources/XiEditor/EditViewController.swift
index 21874bd7..01c96145 100644
--- a/Sources/XiEditor/EditViewController.swift
+++ b/Sources/XiEditor/EditViewController.swift
@@ -325,6 +325,9 @@ class EditViewController: NSViewController, EditViewDataSource, FindDelegate, Sc
         if first..<last != visibleLines {
             document.sendWillScroll(first: first, last: last)
             visibleLines = first..<last
+
+            // Cancels the scroll animation to prevent jerky scrolling.
+            scrollView.contentView.setBoundsOrigin(newOrigin)
         }
         editView.needsDisplay = true
     }
diff --git a/Sources/XiEditor/XiClipView.swift b/Sources/XiEditor/XiClipView.swift
index a1392a5d..1026a3dd 100644
--- a/Sources/XiEditor/XiClipView.swift
+++ b/Sources/XiEditor/XiClipView.swift
@@ -21,13 +21,8 @@ protocol ScrollInterested: class {
 class XiClipView: NSClipView {
     weak var delegate: ScrollInterested?
 
-    // Smooth scrolling (like the MacBook trackpad or Apple Magic Mouse) sends scroll events that are chunked, continuous and cumulative, 
-    // and thus the scroll view's clipView's bounds is set properly (in small increments) for each of these small chunks of scrolling. 
-    // Scrolling with notched mice scrolls in discrete units, takes into account acceleration but does not redraw the view when the view is continuously redrawn (like in xi-mac) during scrolling. 
-    // This is because the bounds origin is only set after the scrolling has stopped completely.
-    // We bypass this by simply setting the bound origin immediately. 
     override func scroll(to newOrigin: NSPoint) {
         delegate?.willScroll(to: newOrigin)
-        super.setBoundsOrigin(newOrigin)
+        super.scroll(to: newOrigin)
     }
 }