Support SimpleCov.root being "/" (#14)

lib/simplecov-cobertura.rb

@@ -2,6 +2,7 @@
 
 require 'rexml/document'
 require 'rexml/element'
+require 'pathname'
 
 require_relative 'simplecov-cobertura/version'
 
@@ -94,9 +95,8 @@ def set_package_attributes(package, name, result)
 
       def set_class_attributes(class_, file)
         filename = file.filename
-        path = filename[SimpleCov.root.length+1..-1]
         class_.attributes['name'] = File.basename(filename, '.*')
-        class_.attributes['filename'] = path
+        class_.attributes['filename'] = resolve_filename(filename)
         class_.attributes['line-rate'] = (file.covered_percent/100).round(2).to_s
         class_.attributes['branch-rate'] = '0'
         class_.attributes['complexity'] = '0'
@@ -116,7 +116,15 @@ def set_xml_head(lines=[])
       end
 
       def coverage_output(result)
-        "#{result.covered_lines} / #{result.covered_lines + result.missed_lines} LOC (#{result.covered_percent.round(2)}%) covered." 
+        "#{result.covered_lines} / #{result.covered_lines + result.missed_lines} LOC (#{result.covered_percent.round(2)}%) covered."
+      end
+
+      def resolve_filename(filename)
+        Pathname.new(filename).relative_path_from(project_root).to_s
+      end
+
+      def project_root
+        @project_root ||= Pathname.new(SimpleCov.root)
       end
     end
   end

test/simplecov-cobertura_test.rb

@@ -135,4 +135,21 @@ def test_groups
     assert_equal 'false', last_line.attribute('branch').value
     assert_equal '2', last_line.attribute('hits').value
   end
+
+  def test_supports_root_project_path
+    old_root = SimpleCov.root
+    SimpleCov.root('/')
+    expected_base = old_root[1..-1] # Remove leading "/"
+
+    xml = @formatter.format(@result)
+    doc = Nokogiri::XML::Document.parse(xml)
+
+    classes = doc.xpath '/coverage/packages/package/classes/class'
+    assert_equal 1, classes.length
+    clazz = classes.first
+    assert_equal 'simplecov-cobertura_test', clazz.attribute('name').value
+    assert_equal "#{expected_base}/test/simplecov-cobertura_test.rb", clazz.attribute('filename').value
+  ensure
+    SimpleCov.root(old_root)
+  end
 end