sprint_calculator.rb

logins = %i{zabrovskiy lisichkin serkin sokorev romnychev minzhynkov mescheryakova shipiev svyatskaya bykovchenko}

logins.inject do |result, login|
  user_id = User.where(login: login).first.id
  issues = Issue.where(assigned_to_id: user_id, fixed_version_id: 2279).
  spent_full = 
    issues.joins(:time_entries).where('time_entries.created_on >= DATE("2015-09-15")').
    pluck('SUM(time_entries.hours) AS sum_hours').first
  est = issues.pluck('SUM(issues.estimated_hours) AS est_hours').first 
  coef = est.to_f/spent_full.to_f
  
  result.merge login => {coef: coef, est: est, spent_full: spent_full}
end