gitlab-org--gitlab-foss/app/models/protected_branch.rb

class ProtectedBranch < ActiveRecord::Base
  include Gitlab::ShellAdapter
  include ProtectedRef

  has_many :merge_access_levels, dependent: :destroy
  has_many :push_access_levels, dependent: :destroy

  validates :merge_access_levels, length: { is: 1, message: "are restricted to a single instance per protected branch." }
  validates :push_access_levels, length: { is: 1, message: "are restricted to a single instance per protected branch." }

  accepts_nested_attributes_for :push_access_levels
  accepts_nested_attributes_for :merge_access_levels

  # Check if branch name is marked as protected in the system
  def self.protected?(project, ref_name)
    return true if project.empty_repo? && default_branch_protected?

    self.matching(ref_name, protected_refs: project.protected_branches).present?
  end

  def self.default_branch_protected?
    current_application_settings.default_branch_protection == Gitlab::Access::PROTECTION_FULL ||
      current_application_settings.default_branch_protection == Gitlab::Access::PROTECTION_DEV_CAN_MERGE
  end
end