End of Life Ruby 3.0 has reached end of life and gets no more fixes. Switch to Ruby 4.0 →

instance method

URI::Generic#set_userinfo

set_userinfo(user, password = nil)

# File tmp/rubies/ruby-3.0.5/lib/uri/generic.rb, line 509
def set_userinfo(user, password = nil)
  unless password
    user, password = split_userinfo(user)
  end
  @user     = user
  @password = password if password

  [@user, @password]
end

Protected setter for the user component, and password if available (with validation).