diff --git a/spec/text-editor-presenter-spec.coffee b/spec/text-editor-presenter-spec.coffee
index 98285c7b2..36395feed 100644
--- a/spec/text-editor-presenter-spec.coffee
+++ b/spec/text-editor-presenter-spec.coffee
@@ -893,7 +893,7 @@ describe "TextEditorPresenter", ->
           expect(getState(presenter).content.scrollTop).toBe 13
 
         it "scrolls down automatically when the model is changed", ->
-          presenter = buildPresenter(scrollTop: 0, lineHeight: 10, explicitHeight: 10)
+          presenter = buildPresenter(scrollTop: 0, lineHeight: 10, explicitHeight: 20)
 
           editor.setText("")
           editor.insertNewline()
diff --git a/src/lines-yardstick.coffee b/src/lines-yardstick.coffee
index 6bc691639..3be276412 100644
--- a/src/lines-yardstick.coffee
+++ b/src/lines-yardstick.coffee
@@ -20,10 +20,11 @@ class LinesYardstick
     targetTop = pixelPosition.top
     targetLeft = pixelPosition.left
     defaultCharWidth = @model.getDefaultCharWidth()
-    row = @lineTopIndex.rowForPixelPosition(targetTop, 'floor')
+    row = @lineTopIndex.rowForPixelPosition(targetTop)
     targetLeft = 0 if targetTop < 0
     targetLeft = Infinity if row > @model.getLastScreenRow()
     row = Math.min(row, @model.getLastScreenRow())
+    row = Math.max(0, row)
 
     line = @model.tokenizedLineForScreenRow(row)
     lineNode = @lineNodesProvider.lineNodeForLineIdAndScreenRow(line?.id, row)