a couple of bugfixes and exception checking, added some specs to impl…

…ement

lib/munger/data.rb

@@ -16,7 +16,7 @@ def initialize(options = {})
     end
 
     def columns
-      @columns ||= @data.first.keys
+      @columns ||= clean_data(@data.first).to_hash.keys
     end
 
     # :default:	The default value to use for the column in existing rows. 

lib/munger/report.rb

@@ -200,19 +200,20 @@ def do_add_aggregate_rows
       end
 
       def calculate_aggregate(type, data)
+        return 0 if !data
         if type.is_a? Proc
           type.call(data)
         else
           case type
           when :count
             data.size
           when :average
-            sum = data.inject {|sum, n| sum + n.to_i }
-            (sum / data.size)
+            sum = data.inject(0) {|sum, n| sum + n.to_i }
+            (sum / data.size).to_i rescue 0
           when :product
-            data.inject {|prod, n| prod * n.to_i }
+            data.inject(0) {|prod, n| prod * n.to_i }
           else
-            data.inject {|sum, n| sum + n.to_i }
+            data.inject(0) {|sum, n| sum + n.to_i }
           end
         end
       end
@@ -236,14 +237,14 @@ def do_add_groupings
                 new_data << group_row
               end
               current[group] = next_row[:data][group]
-              level =- 1
+              level -= 1
             end 
           else  # last row
             level = @grouping_level
             sub.reverse.each do |group|
-              group_row = {:data => {}, :meta => {:group => 1}}
+              group_row = {:data => {}, :meta => {:group => level}}
               new_data << group_row
-              level =- 1
+              level -= 1
             end
           end
         end

spec/spec_data.rb

@@ -113,4 +113,8 @@
 
   it "should be able to group the data like sql"  # like sql group command, give aggregation block
 
+  it "should be able to add two Munger::Datas together if they have the same columns"
+
+  it "(maybe) should be able to zip two Munger::Datas together given a unique key column in each"
+
 end

spec/spec_render_html.rb

@@ -61,6 +61,8 @@
     html = Munger::Render::Html.new(@report).render
     html.should have_tag('td.highlight')
   end
+
+  it "should render column styles"
 
   it "should render default css if you ask" 
 

spec/spec_report.rb

@@ -58,6 +58,8 @@
     @report.get_subgroup_rows.should have(6).items
   end
 
+  it "should be able to add subgroup headers"
+
   it "should be able to subgroup in multiple dimensions"
 
   it "should be able to aggregate columns into subgroup rows" do
@@ -125,6 +127,8 @@
     janet[:cell_styles][:age].should eql(["highlight"])
   end
 
+  it "should be able to style columns"
+
   it "should be able to attach formatting independent of content"
   # so can format numbers without hurting ability to aggregate correctly
   # or add hyperlinks using data from columns not being shown