Add the "Code" Cycle Analytics section.

1. Record the `wip_flag_first_removed_at` and
   `first_assigned_to_user_other_than_author` metrics for a merge
   request. Use a `merge_request_metrics` table, similar to the one for
   `issues`. Metrics are recorded `after_save`.

2. Move larger queries to a `CycleAnalytics::Queries` module.

1 files changed, 12 insertions, 9 deletions

diff --git a/app/models/cycle_analytics.rb b/app/models/cycle_analytics.rb
index d037b1fef12..68efa826b5a 100644
--- a/app/models/cycle_analytics.rb
+++ b/app/models/cycle_analytics.rb
@@ -2,20 +2,22 @@ class CycleAnalytics
   def issue
     issues = Issue.includes(:metrics).where("issue_metrics.id IS NOT NULL").references(:issue_metrics).to_a
     start_time_fn = -> (issue) { issue.created_at  }
-    end_time_fn = -> (issue) { issue.metrics.first_associated_with_milestone_at.presence || issue.metrics.first_added_to_board_at.presence }
-
-    calculate_metric(issues, start_time_fn, end_time_fn)
+    calculate_metric(issues, start_time_fn, Queries::issue_first_associated_with_milestone_or_first_added_to_list_label_time)
   end
 
   def plan
     issues = Issue.includes(:metrics).where("issue_metrics.id IS NOT NULL").references(:issue_metrics).to_a
-    start_time_fn = -> (issue) { issue.metrics.first_associated_with_milestone_at.presence || issue.metrics.first_added_to_board_at.presence }
-    end_time_fn = lambda do |issue|
-      merge_requests = issue.closed_by_merge_requests
-      merge_requests.map(&:created_at).min if merge_requests.present?
-    end
+    calculate_metric(issues,
+                     Queries::issue_first_associated_with_milestone_or_first_added_to_list_label_time,
+                     Queries::issue_closing_merge_request_opened_time)
+  end
 
-    calculate_metric(issues, start_time_fn, end_time_fn)
+  def code
+    issues = Issue.all.to_a
+    start_time_fn = -> (merge_request) { merge_request.created_at }
+    calculate_metric(issues.map(&:closed_by_merge_requests).flatten,
+                     start_time_fn,
+                     Queries::mr_wip_flag_removed_or_assigned_to_user_other_than_author_time)
   end
 
   private
@@ -34,6 +36,7 @@ class CycleAnalytics
   end
 
   def median(coll)
+    return if coll.empty?
     size = coll.length
     (coll[size / 2] + coll[(size - 1) / 2]) / 2.0
   end