Implement partial redraw on editor changes

atom-minimap · Dec 16, 2014 · 0c50eb5 · 0c50eb5
1 parent 0c6849d
commit 0c50eb5
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diff --git a/lib/minimap-element.coffee b/lib/minimap-element.coffee
@@ -61,6 +61,9 @@ class MinimapElement extends HTMLElement
   setModel: (@minimap) ->
     @subscriptions.add @minimap.onDidChangeScrollTop => @requestUpdate()
     @subscriptions.add @minimap.onDidChangeScrollLeft => @requestUpdate()
+    @subscriptions.add @minimap.onDidChange (change) =>
+      @pendingChanges.push(change)
+      @requestUpdate()
 
     @minimap
 

diff --git a/spec/minimap-element-spec.coffee b/spec/minimap-element-spec.coffee
@@ -148,6 +148,24 @@ describe 'MinimapElement', ->
           expect(canvas.offsetWidth).toEqual(minimapElement.offsetWidth)
           expect(canvas.offsetHeight).toEqual(minimapElement.offsetHeight + minimap.getLineHeight())
 
+      describe 'when the editor visible content is changed', ->
+
+        beforeEach ->
+          editor.setScrollLeft(0)
+          editor.setScrollTop(1400)
+          editor.setSelectedBufferRange [[101, 0], [102, 20]]
+          nextAnimationFrame()
+
+          spyOn(minimapElement, 'drawLines').andCallThrough()
+          editor.insertText 'foo'
+
+        it 'rerenders the part that have changed', ->
+          nextAnimationFrame()
+
+          expect(minimapElement.drawLines).toHaveBeenCalled()
+          expect(minimapElement.drawLines.calls[1].args[1]).toEqual(100)
+          expect(minimapElement.drawLines.calls[1].args[2]).toEqual(101)
+
     describe 'when minimap.displayMinimapOnLeft setting is true', ->
       beforeEach ->
         atom.config.set 'minimap.displayMinimapOnLeft', true