Only autoscroll selections to center if they are offscreen

spec/app/editor-spec.coffee

@@ -941,10 +941,14 @@ describe "Editor", ->
         expect(editor.scrollTop()).toBeGreaterThan(0)
 
     describe "when the selected buffer range is assigned with the autoscroll option set to true", ->
-      it "centers the selection in the viewport if possible", ->
-        setEditorHeightInLines(editor, 8)
+      it "centers the selection in the viewport if its vertical center is currently offscreen", ->
+        setEditorHeightInLines(editor, 4)
+
+        editor.setSelectedBufferRange([[2, 0], [4, 0]], autoscroll: true)
+        expect(editor.scrollTop()).toBe 0
+
         editor.setSelectedBufferRange([[6, 0], [8, 0]], autoscroll: true)
-        expect(editor.scrollTop()).toBe 3 * editor.lineHeight
+        expect(editor.scrollTop()).toBe 5 * editor.lineHeight
 
   describe "cursor rendering", ->
     describe "when the cursor moves", ->

src/app/editor.coffee

@@ -502,9 +502,14 @@ class Editor extends View
 
   scrollVertically: (pixelPosition, {center}={}) ->
     scrollViewHeight = @scrollView.height()
+    scrollTop = @scrollTop()
+    scrollBottom = scrollTop + scrollViewHeight
 
     if center
-      @scrollTop(pixelPosition.top - (scrollViewHeight / 2))
+      console.log scrollTop, pixelPosition.top, scrollBottom
+
+      unless scrollTop < pixelPosition.top < scrollBottom
+        @scrollTop(pixelPosition.top - (scrollViewHeight / 2))
     else
       linesInView = @scrollView.height() / @lineHeight
       maxScrollMargin = Math.floor((linesInView - 1) / 2)
@@ -512,10 +517,9 @@ class Editor extends View
       margin = scrollMargin * @lineHeight
       desiredTop = pixelPosition.top - margin
       desiredBottom = pixelPosition.top + @lineHeight + margin
-
-      if desiredBottom > @scrollTop() + scrollViewHeight
+      if desiredBottom > scrollBottom
         @scrollTop(desiredBottom - scrollViewHeight)
-      else if desiredTop < @scrollTop()
+      else if desiredTop < scrollTop
         @scrollTop(desiredTop)
 
   scrollHorizontally: (pixelPosition) ->