Added line_styles module

lib/google_chart.rb

@@ -10,5 +10,6 @@ module GoogleChart
 require 'google_chart/data'
 require 'google_chart/grid_lines'
 require 'google_chart/legends'
+require 'google_chart/line_styles'
 require 'google_chart/sizes'
 require 'google_chart/titles'

lib/google_chart/line_styles.rb

@@ -0,0 +1,30 @@
+module GoogleChart
+  module LineStyles
+    @@line_styles = { :solid => [1,1,0], :dash => [1,3,2], :dot => [1,1,2] }
+    @@default_line_style = :solid
+    @@default_line_width = 1
+
+    def style
+      @style ||= []
+      @width ||= []
+
+      # Pad @style and @width with defaults until they are equal in length
+      (@style.size - @width.size).times { @width << @@default_line_width }
+      (@width.size - @style.size).times { @style << @@default_line_style }
+
+      unless @style.empty?
+        'chls=' + (0...@style.size).collect {|i|
+          @@line_styles[@style[i]].collect {|n| n * @width[i] }.join(',')
+        }.join('|')
+      end
+    end
+
+    def style=(style)
+      @style = [style].flatten
+    end
+
+    def width=(width)
+      @width = [width].flatten
+    end
+  end
+end

test/google_chart/test_line_styles.rb

@@ -0,0 +1,45 @@
+require File.dirname(__FILE__) + '/../test_helper'
+
+FooChart.class_eval { include GoogleChart::LineStyles }
+
+class TestLineStyles < Test::Unit::TestCase
+  def test_should_not_have_line_styles_by_default
+    assert_nil(FooChart.new.style)
+  end
+
+  def test_should_be_able_to_provide_solid_line_style
+    assert_equal('chls=1,1,0', FooChart.new(:style => :solid).style)
+  end
+
+  def test_should_be_able_to_provide_dash_line_style
+    assert_equal('chls=1,3,2', FooChart.new(:style => :dash).style)
+  end
+
+  def test_should_be_able_to_provide_dot_line_style
+    assert_equal('chls=1,1,2', FooChart.new(:style => :dot).style)
+  end
+
+  def test_should_be_able_to_provide_multiple_line_styles
+    assert_equal('chls=1,3,2|1,1,2|1,1,0', FooChart.new(:style => [:dash, :dot, :solid]).style)
+  end
+
+  def test_should_be_able_to_provide_line_width
+    assert_equal('chls=2,2,0', FooChart.new(:width => 2).style)
+  end
+
+  def test_should_be_able_to_provide_line_width_and_line_style
+    assert_equal('chls=2,6,4', FooChart.new(:style => :dash, :width => 2).style)
+  end
+
+  def test_should_be_able_to_provide_multiple_line_widths_and_line_styles
+    assert_equal('chls=2,2,4|3,9,6', FooChart.new(:style => [:dot, :dash], :width => [2, 3]).style)
+  end
+
+  def test_should_use_default_line_width_when_there_are_more_styles_than_widths
+    assert_equal('chls=2,2,4|1,3,2|1,1,0', FooChart.new(:style => [:dot, :dash, :solid], :width => 2).style)
+  end
+
+  def test_should_use_default_line_style_when_there_are_more_widths_than_styles
+    assert_equal('chls=2,2,4|3,3,0|2,2,0', FooChart.new(:style => :dot, :width => [2, 3, 2]).style)
+  end
+end