Escape special characters in chart `StrVal`

So that, for example, pie charts can render with labels
that include an ampersand

1 files changed, 9 insertions, 0 deletions

diff --git a/test/drawing/tc_str_val.rb b/test/drawing/tc_str_val.rb
index 0e4ca835..e4547f62 100644
--- a/test/drawing/tc_str_val.rb
+++ b/test/drawing/tc_str_val.rb
@@ -4,6 +4,7 @@ class TestStrVal < Test::Unit::TestCase
 
   def setup
     @str_val = Axlsx::StrVal.new :v => "1"
+    @str_val_with_special_characters = Axlsx::StrVal.new :v => "a & b <c>"
   end
 
   def test_initialize
@@ -18,4 +19,12 @@ class TestStrVal < Test::Unit::TestCase
     assert_equal(doc.xpath("//c:pt/c:v[text()='1']").size, 1)
   end
 
+  def test_to_xml_string_special_characters
+    str = '<?xml version="1.0" encoding="UTF-8"?>'
+    str << '<c:chartSpace xmlns:c="' << Axlsx::XML_NS_C << '">'
+    str << @str_val_with_special_characters.to_xml_string(0)
+    doc = Nokogiri::XML(str)
+    assert_equal(doc.xpath("//c:pt/c:v[text()='a & b <c>']").size, 1)
+  end
+
 end