Allow from address to fall back to parent mailer

app/mailers/passwordless/mailer.rb

@@ -3,7 +3,7 @@
 module Passwordless
  # The mailer responsible for sending Passwordless' mails.
  class Mailer < Passwordless.config.parent_mailer.constantize
- default from: Passwordless.config.default_from_address
+ default Passwordless.config.mailer_defaults
 
  # Sends a token and a magic link
  #

lib/passwordless/config.rb

@@ -50,6 +50,12 @@ class Configuration
  def initialize
  set_defaults!
  end
+
+ def mailer_defaults
+ # Compacting the Hash removes all keys with nil values, allowing to let
+ # the `from` address fall back to the parent mailer's default.
+ { from: default_from_address }.compact
+ end
  end
 
  module Configurable
@@ -67,5 +73,4 @@ def reset_config!
  @config = Configuration.new
  end
  end
-
 end

test/mailers/passwordless/mailer_test.rb

@@ -35,4 +35,14 @@ class Passwordless::MailerTest < ActionMailer::TestCase
  assert_match /sign in: hello\n/, email.body.to_s
  assert_match %r{/admins/sign_in/#{session.identifier}/hello}, email.body.to_s
  end
+
+ test("without default_from_address falls back to parent_mailer") do
+ WithConfig.with_config({default_from_address: nil, parent_mailer: "ApplicationMailer"}) do
+ email = Passwordless::Mailer.sign_in(
+ Passwordless::Session.create!(authenticatable: users(:alice), token: "hello")
+ )
+
+ assert_equal ["[email protected]"], email.from
+ end
+ end
 end