Define the mailer inside the spec with let

Author: ka8725

spec/rspec/rails/matchers/have_enqueued_mail_spec.rb

@@ -3,6 +3,45 @@
 if RSpec::Rails::FeatureCheck.has_active_job?
   require "action_mailer"
   require "rspec/rails/matchers/have_enqueued_mail"
+
+  class GlobalIDArgument
+    include GlobalID::Identification
+    def id; 1; end
+    def to_global_id(options = {}); super(options.merge(app: 'rspec-rails')); end
+  end
+
+  class TestMailer < ActionMailer::Base
+    def test_email; end
+    def email_with_args(arg1, arg2); end
+    def email_with_optional_args(required_arg, optional_arg = nil); end
+  end
+
+  class AnotherTestMailer < ActionMailer::Base
+    def test_email; end
+  end
+
+  if RSpec::Rails::FeatureCheck.has_action_mailer_unified_delivery?
+    class UnifiedMailer < ActionMailer::Base
+      self.delivery_job = ActionMailer::MailDeliveryJob
+
+      def test_email; end
+      def email_with_args(arg1, arg2); end
+    end
+
+    if RSpec::Rails::FeatureCheck.has_action_mailer_legacy_delivery_job?
+      class DeliveryJobSubClass < ActionMailer::DeliveryJob
+      end
+    else
+      class DeliveryJobSubClass < ActionMailer::MailDeliveryJob
+      end
+    end
+
+    class UnifiedMailerWithDeliveryJobSubClass < ActionMailer::Base
+      self.delivery_job = DeliveryJobSubClass
+
+      def test_email; end
+    end
+  end
 end
 
 RSpec.describe "HaveEnqueuedMail matchers", skip: !RSpec::Rails::FeatureCheck.has_active_job? do

spec/rspec/rails/matchers/send_email_spec.rb

@@ -1,9 +1,26 @@
 # frozen_string_literal: true
 
 RSpec.describe "send_email" do
+  let(:mailer) do
+    Class.new(ActionMailer::Base) do
+      self.delivery_method = :test
+
+      def test_email
+        mail(
+          from: "[email protected]",
+          cc: "[email protected]",
+          bcc: "[email protected]",
+          to: "[email protected]",
+          subject: "Test email",
+          body: "Test email body"
+        )
+      end
+    end
+  end
+
   it "checks email sending by all params together" do
     expect {
-      TestMailer.test_email.deliver_now
+      mailer.test_email.deliver_now
     }.to send_email(
       from: "[email protected]",
       to: "[email protected]",
@@ -16,21 +33,21 @@
 
   it "checks email sending by no params" do
     expect {
-      TestMailer.test_email.deliver_now
+      mailer.test_email.deliver_now
     }.to send_email
   end
 
   it "has a negated version" do
     expect {
-      TestMailer.test_email.deliver_now
+      mailer.test_email.deliver_now
     }.to_not send_email(
       from: "[email protected]"
     )
   end
 
   it "fails with a clear message" do
     expect {
-      expect { TestMailer.test_email.deliver_now }.to send_email(from: '[email protected]')
+      expect { mailer.test_email.deliver_now }.to send_email(from: '[email protected]')
     }.to raise_error(RSpec::Expectations::ExpectationNotMetError, <<~MSG.strip)
       No matching emails were sent.
 
@@ -51,13 +68,13 @@
 
   it "fails with a clear message for negated version" do
     expect {
-      expect { TestMailer.test_email.deliver_now }.to_not send_email(from: "[email protected]")
+      expect { mailer.test_email.deliver_now }.to_not send_email(from: "[email protected]")
     }.to raise_error(RSpec::Expectations::ExpectationNotMetError, "Expected not to send an email but it was sent.")
   end
 
   it "fails for multiple matches" do
     expect {
-      expect { 2.times { TestMailer.test_email.deliver_now } }.to send_email(from: "[email protected]")
+      expect { 2.times { mailer.test_email.deliver_now } }.to send_email(from: "[email protected]")
     }.to raise_error(RSpec::Expectations::ExpectationNotMetError, <<~MSG.strip)
       More than 1 matching emails were sent.
 

spec/spec_helper.rb

@@ -20,8 +20,6 @@ def self.world=(world)
   end
 end
 
-ActionMailer::Base.delivery_method = :test
-
 I18n.enforce_available_locales = true
 
 require 'rspec/support/spec'