lib/churn/churn_calculator.rb in churn-0.0.33 vs lib/churn/churn_calculator.rb in churn-0.0.34

@@ -42,15 +42,43 @@
     # prepares the data for the given project to be reported.
     # reads git/svn logs analyzes the output, generates a report and either formats as a nice string or returns hash.
     # @param [Bolean] format to return the data, true for string or false for hash
     # @return [Object] returns either a pretty string or a hash representing the chrun of the project
     def report(print = true)
-      self.emit
-      self.analyze
-      print ? self.to_s : self.to_h
+      if @churn_options.history
+        generate_history
+      else
+        self.emit
+        self.analyze
+        print ? self.to_s : self.to_h
+      end
     end
 
+    # this method generates the past history of a churn project from first commit to current
+    # running the report for oldest commits first so they are built up correctly
+    def generate_history
+      if @source_control.is_a?(GitAnalyzer)
+        begin
+          history_starting_point = Chronic.parse(@churn_options.history)
+          @source_control.get_commit_history.each do |commit|
+            `git checkout #{commit}`
+            commit_date = `git show -s --format="%ci"`
+            commit_date = Time.parse(commit_date)
+            next if commit_date < history_starting_point
+            #7776000 == 3.months without adding active support depenancy
+            start_date  = (commit_date - 7776000)
+            `churn -s "#{start_date}"`
+          end
+        ensure
+          `git checkout master`
+        end
+        "churn history complete, this has munipulated git please make sure you are back on HEAD where you expect to be"
+      else
+        raise "currently generate history only supports git"
+      end
+    end
+
     # Emits various data from source control to be analyses later... Currently this is broken up like this as a throwback to metric_fu
     def emit
       @changes   = parse_log_for_changes.reject {|file, change_count| change_count < @minimum_churn_count || @ignore_files.include?(file) }
       @revisions = parse_log_for_revision_changes
     end
@@ -85,10 +113,15 @@
       #TODO crappy place to do this but save hash to revision file but while entirely under metric_fu only choice
       ChurnHistory.store_revision_history(first_revision, hash)
       hash
     end
 
+    def to_s
+      ChurnCalculator.to_s(to_h[:churn])
+    end
+
+    # Pretty print the data as a string for the user
     def self.to_s(hash)
       result = seperator
       result +="* Revision Changes \n"
       result += seperator
       result += "Files: \n"
@@ -108,18 +141,14 @@
       result += "\nMethods: \n"
       method_churn = collect_items(hash[:method_churn], 'method')
       result += display_array(method_churn)
     end
 
-    # Pretty print the data as a string for the user
-    def to_s
-      ChurnCalculator.to_s(to_h[:churn])
-    end
-
     private
 
     def self.collect_items(collection, match)
+      return [] unless collection
       collection.map {|item| (item.delete(match) || {}).merge(item) }
     end
 
     def sort_changes(changes)
       changes.to_a.sort! {|first,second| second[1] <=> first[1]}
@@ -135,23 +164,19 @@
 
     def self.seperator
       "*"*70+"\n"
     end
 
-    def seperator
-      ChurnCalculator.seperator
-    end
-
     def self.git?
-      system("git branch")
+      !!(`git branch 2>&1` && $?.success?)
     end
-
+    
     def self.hg?
-      system("hg branch")
+      !!(`hg branch 2>&1` && $?.success?)
     end
-
+    
     def self.bzr?
-        system("bzr nick")
+      !!(`bzr nick 2>&1` && $?.success?)
     end
 
     def set_source_control(start_date)
       if self.class.git?
         GitAnalyzer.new(start_date)