Brush with spec

app/assets/javascripts/brush.js.coffee

@@ -0,0 +1,23 @@
+class AsciiIo.Brush
+  @cache: {}
+
+  @clearCache: ->
+    @cache = {}
+
+  @create: (options) ->
+    options ||= {}
+
+    key = "#{options.fg}_#{options.bg}_#{options.bright}_#{options.underline}"
+    brush = @cache[key]
+
+    if not brush
+      brush = new AsciiIo.Brush(options)
+      @cache[key] = brush
+
+    brush
+
+  constructor: (options) ->
+    @fg        = options.fg
+    @bg        = options.bg
+    @bright    = options.bright
+    @underline = options.underline

spec/javascripts/brush_spec.coffee

@@ -0,0 +1,26 @@
+describe AsciiIo.Brush, ->
+
+  describe '.clearCache', ->
+
+    it 'resets cache hash', ->
+      AsciiIo.Brush.create()
+      expect(_(AsciiIo.Brush.cache).keys().length > 0).toBeTruthy()
+      AsciiIo.Brush.clearCache()
+      expect(_(AsciiIo.Brush.cache).keys().length).toEqual(0)
+
+  describe '.create', ->
+
+    beforeEach ->
+      AsciiIo.Brush.clearCache()
+
+    it 'returns new brush instance if not cached', ->
+      brush = AsciiIo.Brush.create({ fg: 1})
+      expect(brush instanceof AsciiIo.Brush).toBeTruthy()
+
+    it 'returns existing brush instance if cached', ->
+      brush = AsciiIo.Brush.create({ fg: 1})
+      otherBrush = AsciiIo.Brush.create({ fg: 1, bg: 100 })
+      anotherBrush = AsciiIo.Brush.create({ fg: 1})
+
+      expect(_(AsciiIo.Brush.cache).keys().length).toEqual(2)
+      expect(brush is anotherBrush).toBeTruthy()