Selective multipart delivery

lib/lotus/mailer.rb

@@ -338,7 +338,8 @@ def __part(format)
     end
 
     def __part?(format)
-      !self.class.templates(format).nil?
+      @format == format ||
+        (!@format && !self.class.templates(format).nil?)
     end
   end
 end

lib/lotus/mailer/rendering.rb

@@ -18,6 +18,7 @@ module InstanceMethods
         # @since 0.1.0
         def initialize(locals = {})
           @locals = locals
+          @format = locals.fetch(:format, nil)
           @mail   = Mail.new.tap do |m|
             m.from    = __dsl(:from)
             m.to      = __dsl(:to)

test/delivery_test.rb

@@ -64,26 +64,39 @@
       end
     end
 
-    describe 'test delivery with methods' do
-      before do
-        @user = User.new('Ines', 'ines@deigirls.com')
-        MethodMailer.deliver(user: @user)
-
-        @mail = Lotus::Mailer.deliveries.first
-      end
-
+    describe 'multipart' do
       after do
         Lotus::Mailer.deliveries.clear
       end
 
-      it 'delivers the mail' do
-        Lotus::Mailer.deliveries.length.must_equal 1
+      it 'delivers all the parts by default' do
+        WelcomeMailer.deliver
+
+        mail = Lotus::Mailer.deliveries.first
+        body = mail.body.encoded
+
+        body.must_include %(<h1>Hello World!</h1>)
+        body.must_include %(This is a txt template)
       end
 
-      it 'sends the correct information' do
-        @mail.from.must_equal    ["hello-#{ @user.name.downcase }@example.com"]
-        @mail.to.must_equal      [@user.email]
-        @mail.subject.must_equal "Hello, #{ @user.name }"
+      it 'can deliver only the text part' do
+        WelcomeMailer.deliver(format: :txt)
+
+        mail = Lotus::Mailer.deliveries.first
+        body = mail.body.encoded
+
+        body.wont_include %(<h1>Hello World!</h1>)
+        body.must_include %(This is a txt template)
+      end
+
+      it 'can deliver only the html part' do
+        WelcomeMailer.deliver(format: :html)
+
+        mail = Lotus::Mailer.deliveries.first
+        body = mail.body.encoded
+
+        body.must_include %(<h1>Hello World!</h1>)
+        body.wont_include %(This is a txt template)
       end
     end