Cursor scrolls editor as it moves

Atom.xcodeproj/project.pbxproj

@@ -378,6 +378,7 @@
 				GCC_PREFIX_HEADER = "Atom/Atom-Prefix.pch";
 				INFOPLIST_FILE = "Atom/Atom-Info.plist";
 				PRODUCT_NAME = "$(TARGET_NAME)";
+				STRINGS_FILE_OUTPUT_ENCODING = "UTF-8";
 				WRAPPER_EXTENSION = app;
 			};
 			name = Debug;
@@ -389,6 +390,7 @@
 				GCC_PREFIX_HEADER = "Atom/Atom-Prefix.pch";
 				INFOPLIST_FILE = "Atom/Atom-Info.plist";
 				PRODUCT_NAME = "$(TARGET_NAME)";
+				STRINGS_FILE_OUTPUT_ENCODING = "UTF-8";
 				WRAPPER_EXTENSION = app;
 			};
 			name = Release;

spec/atom/editor-spec.coffee

@@ -1,6 +1,7 @@
 Buffer = require 'buffer'
 Editor = require 'editor'
 $ = require 'jquery'
+_ = require 'underscore'
 fs = require 'fs'
 
 describe "Editor", ->
@@ -43,6 +44,30 @@ describe "Editor", ->
       expect(editor.getPosition()).toEqual(row: 0, col: 0)
 
     describe "vertical movement", ->
+
+      fit "scrolls the buffer with the specified scroll margin when cursor approaches the end of the screen", ->
+        editor.attachToDom()
+        editor.focus()
+        editor.scrollMargin = 3
+        editor.height(editor.lineHeight * 10)
+
+        _.times 6, -> editor.moveDown()
+        expect(editor.scrollTop()).toBe(0)
+
+        editor.moveDown()
+        expect(editor.scrollTop()).toBe(editor.lineHeight)
+        editor.moveDown()
+        expect(editor.scrollTop()).toBe(editor.lineHeight * 2)
+
+        _.times 3, -> editor.moveUp()
+        expect(editor.scrollTop()).toBe(editor.lineHeight * 2)
+
+        editor.moveUp()
+        expect(editor.scrollTop()).toBe(editor.lineHeight)
+
+        editor.moveUp()
+        expect(editor.scrollTop()).toBe(0)
+
       describe "when up is pressed on the first line", ->
         it "moves the cursor to the beginning of the line, but retains the goal column", ->
           editor.setPosition(row: 0, col: 4)
@@ -65,7 +90,7 @@ describe "Editor", ->
           editor.moveUp()
           expect(editor.getPosition().col).toBe 1
 
-        fit "retains a goal column of 0", ->
+        it "retains a goal column of 0", ->
           lastLineIndex = buffer.getLines().length - 1
           lastLine = buffer.getLine(lastLineIndex)
           expect(lastLine.length).toBeGreaterThan(0)

spec/spec-helper.coffee

@@ -7,8 +7,8 @@ require 'window'
 
 afterEach ->
   (new Native).resetMainMenu()
-  atom.globalKeymap.reset()
-  $('#jasmine-content').empty()
+  # atom.globalKeymap.reset()
+  # $('#jasmine-content').empty()
 
 window.atom = new (require 'app')
 

src/atom/cursor.coffee

@@ -68,3 +68,12 @@ class Cursor extends Template
       position = @parentView.pixelPositionFromPoint(@point)
       @css(position)
 
+      margin = @parentView.scrollMargin * @height()
+      desiredTop = position.top - margin
+      desiredBottom = position.top + @height() + margin
+
+      if desiredBottom > @parentView.scrollBottom()
+        @parentView.scrollBottom(desiredBottom)
+      else if desiredTop < @parentView.scrollTop()
+        @parentView.scrollTop(desiredTop)
+

src/atom/editor.coffee

@@ -14,6 +14,7 @@ class Editor extends Template
 
   viewProperties:
     buffer: null
+    scrollMargin: 2
 
     initialize: () ->
       requireStylesheet 'editor.css'
@@ -57,6 +58,12 @@ class Editor extends Template
       fragment.remove()
       @cursor.updateAbsolutePosition()
 
+    scrollBottom: (newValue) ->
+      if newValue?
+        @scrollTop(newValue - @height())
+      else
+        @scrollTop() + @height()
+
     moveUp: -> @cursor.moveUp()
     moveDown: -> @cursor.moveDown()
     moveRight: -> @cursor.moveRight()

static/editor.css

@@ -5,6 +5,7 @@
   height: 100%;
   background: #333;
   color: white;
+  overflow-y: scroll;
 }
 
 .editor pre {