From 1427dbf540dc349ac43bca25cb1171905132f252 Mon Sep 17 00:00:00 2001
From: Nathan Sobo <nathan@github.com>
Date: Wed, 15 Mar 2017 20:35:25 -0600
Subject: [PATCH] Make lines extend across the entire width of the scroller

This ensures line decorations render properly, even when the content is
narrower than the editor.
---
 spec/text-editor-component-spec.js | 11 ++++++++++-
 src/text-editor-component.js       |  5 ++++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/spec/text-editor-component-spec.js b/spec/text-editor-component-spec.js
index 31498e4a0..8350251a9 100644
--- a/spec/text-editor-component-spec.js
+++ b/spec/text-editor-component-spec.js
@@ -231,6 +231,15 @@ describe('TextEditorComponent', () => {
     expect(lineNumberNodeForScreenRow(component, 1).classList.contains('folded')).toBe(true)
   })
 
+  it('makes lines at least as wide as the scroller', async () => {
+    const {component, element, editor} = buildComponent()
+    const {scroller, gutterContainer} = component.refs
+    editor.setText('a')
+    await component.getNextUpdatePromise()
+
+    expect(element.querySelector('.line').offsetWidth).toBe(scroller.offsetWidth - gutterContainer.offsetWidth)
+  })
+
   describe('mini editors', () => {
     it('adds the mini attribute', () => {
       const {element, editor} = buildComponent({mini: true})
@@ -395,7 +404,7 @@ describe('TextEditorComponent', () => {
     it('correctly autoscrolls after inserting a line that exceeds the current content width', async () => {
       const {component, element, editor} = buildComponent()
       const {scroller} = component.refs
-      element.style.width = component.getScrollWidth() + 'px'
+      element.style.width = component.getGutterContainerWidth() + component.measurements.longestLineWidth + 'px'
       await component.getNextUpdatePromise()
 
       editor.setCursorScreenPosition([0, Infinity])
diff --git a/src/text-editor-component.js b/src/text-editor-component.js
index 2deb4d803..1c0511d70 100644
--- a/src/text-editor-component.js
+++ b/src/text-editor-component.js
@@ -1496,7 +1496,10 @@ class TextEditorComponent {
     if (this.getModel().isSoftWrapped()) {
       return this.getClientWidth() - this.getGutterContainerWidth()
     } else {
-      return Math.round(this.measurements.longestLineWidth + this.measurements.baseCharacterWidth)
+      return Math.max(
+        Math.round(this.measurements.longestLineWidth + this.measurements.baseCharacterWidth),
+        this.measurements.scrollerWidth - this.getGutterContainerWidth()
+      )
     }
   }