module ActiveSupport::Deprecation::Behavior

def arity_coerce(behavior)
  unless behavior.respond_to?(:call)
    raise ArgumentError, "#{behavior.inspect} is not a valid deprecation behavior."
  end
  case arity_of_callable(behavior)
  when 2
    ->(message, callstack, deprecator) do
      behavior.call(message, callstack)
    end
  when -2..3
    behavior
  else
    ->(message, callstack, deprecator) do
      behavior.call(message, callstack, deprecator.deprecation_horizon, deprecator.gem_name)
    end
  end
end

def arity_of_callable(callable)
  callable.respond_to?(:arity) ? callable.arity : callable.method(:call).arity
end

Returns the current behavior or if one isn't set, defaults to +:stderr+.

def behavior
  @behavior ||= [DEFAULT_BEHAVIORS[:stderr]]
end

more performant.
all deprecation behaviors. This is similar to the +:silence+ option but
config.active_support.report_deprecations = false to disable
If you are using \Rails, you can set

}
# custom stuff
deprecator.behavior = ->(message, callstack, deprecation_horizon, gem_name) {
deprecator.behavior = MyCustomHandler
deprecator.behavior = [:stderr, :log]
deprecator.behavior = :stderr
deprecator = ActiveSupport::Deprecation.new

because they happen before \Rails boots up.
Deprecation warnings raised by gems are not affected by this setting
Setting behaviors only affects deprecations that happen after boot time.

[+:silence+] Do nothing.
[+:report+] Use ActiveSupport::ErrorReporter to report deprecations.
[+:notify+] Use ActiveSupport::Notifications to notify +deprecation.rails+.
[+:log+] Log all deprecation warnings to +Rails.logger+.
[+:stderr+] Log all deprecation warnings to $stderr.
[+:raise+] Raise ActiveSupport::DeprecationException.

Available behaviors:

or an object that responds to +call+.
Sets the behavior to the specified value. Can be a single value, array,

def behavior=(behavior)
  @behavior = Array(behavior).map { |b| DEFAULT_BEHAVIORS[b] || arity_coerce(b) }
end

Returns the current behavior for disallowed deprecations or if one isn't set, defaults to +:raise+.

def disallowed_behavior
  @disallowed_behavior ||= [DEFAULT_BEHAVIORS[:raise]]
end

object that responds to +call+.
value. As with #behavior=, this can be a single value, array, or an
ActiveSupport::Deprecation#disallowed_warnings=) to the specified
Sets the behavior for disallowed deprecations (those configured by

def disallowed_behavior=(behavior)
  @disallowed_behavior = Array(behavior).map { |b| DEFAULT_BEHAVIORS[b] || arity_coerce(b) }
end