From a2729ab271c348541921c1404ff20c4a092ba038 Mon Sep 17 00:00:00 2001
From: Luca Guidi <me@lucaguidi.com>
Date: Wed, 23 Sep 2015 17:45:30 +0200
Subject: [PATCH] Raise error when from/to delivery data is missing

---
 lib/lotus/mailer.rb                     |  8 ++++++++
 test/delivery_test.rb                   | 24 ++++++++++++++++--------
 test/fixtures.rb                        | 16 ++++++++++++++++
 test/fixtures/templates/missing.txt.erb |  1 +
 4 files changed, 41 insertions(+), 8 deletions(-)
 create mode 100644 test/fixtures/templates/missing.txt.erb

diff --git a/lib/lotus/mailer.rb b/lib/lotus/mailer.rb
index 9b87979..7c14dd4 100644
--- a/lib/lotus/mailer.rb
+++ b/lib/lotus/mailer.rb
@@ -8,6 +8,12 @@
 
 module Lotus
   module Mailer
+    class MissingDeliveryDataError < ::StandardError
+      def initialize
+        super("Missing delivery data, please check 'from', 'to' and 'subject'")
+      end
+    end
+
     DEFAULT_TEMPLATE = :txt.freeze
 
     CONTENT_TYPES = {
@@ -134,6 +140,8 @@ module InstanceMethods
       # @since 0.1.0
       def deliver
         mail.deliver
+      rescue ArgumentError
+        raise MissingDeliveryDataError
       end
     end
 
diff --git a/test/delivery_test.rb b/test/delivery_test.rb
index 3ba3536..4406189 100644
--- a/test/delivery_test.rb
+++ b/test/delivery_test.rb
@@ -6,6 +6,22 @@
       Lotus::Mailer.deliveries.clear
     end
 
+    it 'can deliver with specified charset' do
+      CharsetMailer.deliver(charset: charset = 'iso-2022-jp')
+
+      mail = Lotus::Mailer.deliveries.first
+      mail.charset.must_equal             charset
+      mail.parts.first.charset.must_equal charset
+    end
+
+    it "raises error when 'from' isn't specified" do
+      -> { MissingFromMailer.deliver }.must_raise Lotus::Mailer::MissingDeliveryDataError
+    end
+
+    it "raises error when 'to' isn't specified" do
+      -> { MissingToMailer.deliver }.must_raise Lotus::Mailer::MissingDeliveryDataError
+    end
+
     describe 'test delivery with hardcoded values' do
       before do
         WelcomeMailer.deliver
@@ -102,14 +118,6 @@
         body.must_include %(<h1>Hello World!</h1>)
         body.wont_include %(This is a txt template)
       end
-
-      it 'can deliver with specified charset' do
-        CharsetMailer.deliver(charset: charset = 'iso-2022-jp')
-
-        mail = Lotus::Mailer.deliveries.first
-        mail.charset.must_equal             charset
-        mail.parts.first.charset.must_equal charset
-      end
     end
 
     # describe 'custom delivery' do
diff --git a/test/fixtures.rb b/test/fixtures.rb
index 14db975..11dc407 100644
--- a/test/fixtures.rb
+++ b/test/fixtures.rb
@@ -19,6 +19,22 @@ class CharsetMailer
   subject 'こんにちは'
 end
 
+class MissingFromMailer
+  include Lotus::Mailer
+  template 'missing'
+
+  to      "recipient@example.com"
+  subject "Hello"
+end
+
+class MissingToMailer
+  include Lotus::Mailer
+  template 'missing'
+
+  from    "sender@example.com"
+  subject "Hello"
+end
+
 class User < Struct.new(:name, :email); end
 
 class LazyMailer
diff --git a/test/fixtures/templates/missing.txt.erb b/test/fixtures/templates/missing.txt.erb
new file mode 100644
index 0000000..b69a6b1
--- /dev/null
+++ b/test/fixtures/templates/missing.txt.erb
@@ -0,0 +1 @@
+Missin'