Add exactly, at_least, at_most functionality for have_enqueued_mail matcher.

Author: Joel Lubrano

lib/rspec/rails/matchers/have_enqueued_mail.rb

@@ -13,6 +13,8 @@ def initialize(mailer_class, method_name)
           @mailer_class = mailer_class
           @method_name = method_name
           @args = []
+          @job_matcher = ActiveJob::HaveEnqueuedJob.new(ActionMailer::DeliveryJob)
+          set_expected_count(:exactly, 1)
         end
 
         def description
@@ -23,18 +25,33 @@ def matches?(block)
           raise ArgumentError, 'have_enqueued_mail and enqueue_mail only work with block arguments' unless block.respond_to?(:call)
           check_active_job_adapter
 
-          job_matcher = ActiveJob::HaveEnqueuedJob.new(ActionMailer::DeliveryJob)
-          job_matcher.with(*mailer_args)
-          job_matcher.matches?(block)
+          @job_matcher.with(*mailer_args)
+          @job_matcher.matches?(block)
         end
 
         def with(*args)
           @args = args
           self
         end
 
+        %i[exactly at_least at_most].each do |method|
+          define_method(method) do |count|
+            @job_matcher.public_send(method, count)
+            set_expected_count(method, count)
+            self
+          end
+        end
+
+        %i[once twice thrice].each do |method|
+          define_method(method) do
+            @job_matcher.public_send(method)
+            exactly(method)
+          end
+        end
+
         def failure_message
           base_message.tap do |msg|
+            msg << " #{expected_count_message}"
             msg << " with #{@args}" if @args.any?
           end
         end
@@ -49,6 +66,10 @@ def base_message
           "expected to enqueue #{@mailer_class.name}.#{@method_name}"
         end
 
+        def expected_count_message
+          "#{@expected_count_type.to_s.tr('_', ' ')} #{@expected_count} #{@expected_count == 1 ? 'time' : 'times'}"
+        end
+
         def mailer_args
           [@mailer_class.name, @method_name.to_s, 'deliver_now'] + @args
         end
@@ -57,6 +78,16 @@ def check_active_job_adapter
           return if ::ActiveJob::QueueAdapters::TestAdapter === ::ActiveJob::Base.queue_adapter
           raise StandardError, "To use HaveEnqueuedMail matcher set `ActiveJob::Base.queue_adapter = :test`"
         end
+
+        def set_expected_count(relativity, count)
+          @expected_count_type = relativity
+          @expected_count = case count
+                            when :once then 1
+                            when :twice then 2
+                            when :thrice then 3
+                            else Integer(count)
+                            end
+        end
       end
 
       # @api public

spec/rspec/rails/matchers/have_enqueued_mail_spec.rb

@@ -16,6 +16,13 @@ def email_with_args(arg1, arg2); end
     ActiveJob::Base.queue_adapter = :test
   end
 
+  around do |example|
+    original_logger = ActiveJob::Base.logger
+    ActiveJob::Base.logger = Logger.new(nil) # Silence messages "[ActiveJob] Enqueued ...".
+    example.run
+    ActiveJob::Base.logger = original_logger
+  end
+
   describe "have_enqueued_mail" do
     it "passes when a mailer method is called with deliver_later" do
       expect {
@@ -42,16 +49,66 @@ def email_with_args(arg1, arg2); end
     end
 
     it "passes when negated" do
-      expect { }.not_to have_enqueued_email(TestMailer, :test_email)
+      expect { }.not_to have_enqueued_mail(TestMailer, :test_email)
+    end
+
+    it "counts only emails enqueued in the block" do
+      TestMailer.test_email.deliver_later
+
+      expect {
+        TestMailer.test_email.deliver_later
+      }.to have_enqueued_mail(TestMailer, :test_email).once
     end
 
-    # it "counts only emails enqueued in the block" do
-      # TestMailer.test_email
+    it "fails when too many emails are enqueued" do
+      expect {
+        expect {
+          TestMailer.test_email.deliver_later
+          TestMailer.test_email.deliver_later
+        }.to have_enqueued_mail(TestMailer, :test_email).exactly(1)
+      }.to raise_error(/expected to enqueue TestMailer.test_email exactly 1 time/)
+    end
 
-      # expect {
-        # TestMailer.test_email
-      # }.to have_enqueued_email(TestMailer, :test_email).once
-    # end
+    it "passes with :once count" do
+      expect {
+        TestMailer.test_email.deliver_later
+      }.to have_enqueued_mail(TestMailer, :test_email).once
+    end
+
+    it "passes with :twice count" do
+      expect {
+        TestMailer.test_email.deliver_later
+        TestMailer.test_email.deliver_later
+      }.to have_enqueued_mail(TestMailer, :test_email).twice
+    end
+
+    it "passes with :thrice count" do
+      expect {
+        TestMailer.test_email.deliver_later
+        TestMailer.test_email.deliver_later
+        TestMailer.test_email.deliver_later
+      }.to have_enqueued_mail(TestMailer, :test_email).thrice
+    end
+
+    it "matches based on mailer class and method name" do
+      expect {
+        TestMailer.test_email.deliver_later
+        TestMailer.email_with_args(1, 2).deliver_later
+      }.to have_enqueued_mail(TestMailer, :test_email).once
+    end
+
+    it "passes with multiple emails" do
+      expect {
+        TestMailer.test_email.deliver_later
+        TestMailer.email_with_args(1, 2).deliver_later
+      }.to have_enqueued_mail(TestMailer, :test_email).and have_enqueued_mail(TestMailer, :email_with_args)
+    end
+
+    it "passes for mailer methods that accept arguments when the provided argument matcher is not used" do
+      expect {
+        TestMailer.email_with_args(1, 2).deliver_later
+      }.to have_enqueued_mail(TestMailer, :email_with_args)
+    end
 
     it "passes with provided argument matchers" do
       expect {
@@ -72,15 +129,15 @@ def email_with_args(arg1, arg2); end
     it "generates a failure message with arguments" do
       expect {
         expect { }.to have_enqueued_email(TestMailer, :email_with_args).with(1, 2)
-      }.to raise_error(/expected to enqueue TestMailer.email_with_args with \[1, 2\]/)
+      }.to raise_error(/expected to enqueue TestMailer.email_with_args exactly 1 time with \[1, 2\]/)
     end
 
     it "throws descriptive error when no test adapter set" do
       queue_adapter = ActiveJob::Base.queue_adapter
       ActiveJob::Base.queue_adapter = :inline
 
       expect {
-        expect { TestMailer.test_email }.to have_enqueued_mail(TestMailer, :test_email)
+        expect { TestMailer.test_email.deliver_later }.to have_enqueued_mail(TestMailer, :test_email)
       }.to raise_error("To use ActiveJob matchers set `ActiveJob::Base.queue_adapter = :test`")
 
       ActiveJob::Base.queue_adapter = queue_adapter