From 2e517425bc086003f8c1fa94aa410764639fd99e Mon Sep 17 00:00:00 2001
From: abe33 <cedric.nehemie@gmail.com>
Date: Fri, 12 Dec 2014 15:47:59 +0100
Subject: [PATCH] Add more scroll related methods

---
 lib/minimap.coffee       |  4 ++++
 spec/minimap-spec.coffee | 15 +++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/lib/minimap.coffee b/lib/minimap.coffee
index 2abe557c..a0098aa4 100644
--- a/lib/minimap.coffee
+++ b/lib/minimap.coffee
@@ -18,6 +18,10 @@ class Minimap
 
   getLineHeight: -> @charHeight + @interline
 
+  getMinimapScrollHeight: -> Math.max(0, @getHeight() - @textEditor.getHeight())
+
+  canScroll: -> @getMinimapScrollHeight() > 0
+
   subscribeToConfig: ->
     @subscriptions.add atom.config.observe 'minimap.charHeight', (@charHeight) =>
     @subscriptions.add atom.config.observe 'minimap.charWidth', (@charWidth) =>
diff --git a/spec/minimap-spec.coffee b/spec/minimap-spec.coffee
index f2f98c64..4c61f363 100644
--- a/spec/minimap-spec.coffee
+++ b/spec/minimap-spec.coffee
@@ -41,3 +41,18 @@ describe 'Minimap', ->
     editor.setScrollTop(1000)
 
     expect(minimap.getTextEditorScroll()).toEqual(500)
+
+  it 'measures the available minimap scroll', ->
+    editor.setText(largeSample)
+    largeLineCount = editor.getLineCount()
+
+    expect(minimap.getMinimapScrollHeight()).toEqual(largeLineCount * 5 - 50)
+    expect(minimap.canScroll()).toBeTruthy()
+
+  describe 'when there is no scrolling needed to display the whole minimap', ->
+    describe 'measuring the available minimap scroll', ->
+      it 'returns 0', ->
+        editor.setText(smallSample)
+
+        expect(minimap.getMinimapScrollHeight()).toEqual(0)
+        expect(minimap.canScroll()).toBeFalsy()