2 files changed, 149 insertions, 3 deletions
diff --git a/actionmailer/lib/action_mailer/test_case.rb b/actionmailer/lib/action_mailer/test_case.rb
index 251705ae50..e60dda9694 100644
--- a/actionmailer/lib/action_mailer/test_case.rb
+++ b/actionmailer/lib/action_mailer/test_case.rb
@@ -49,9 +49,11 @@ module ActionMailer
         end
 
         def determine_default_mailer(name)
-          name.sub(/Test$/, '').constantize
-        rescue NameError
-          raise NonInferrableMailerError.new(name)
+          mailer = determine_constant_from_test_name(name) do |constant|
+            Class === constant && constant < ActionMailer::Base
+          end
+          raise NonInferrableMailerError.new(name) if mailer.nil?
+          mailer
         end
       end
 
diff --git a/actionmailer/test/test_test.rb b/actionmailer/test/test_test.rb
index 86fd37bea6..139eb53359 100644
--- a/actionmailer/test/test_test.rb
+++ b/actionmailer/test/test_test.rb
@@ -26,3 +26,147 @@ class CrazyStringNameMailerTest < ActionMailer::TestCase
     assert_equal TestTestMailer, self.class.mailer_class
   end
 end
+
+describe TestTestMailer do
+  it "gets the mailer from the test name" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end
+
+describe TestTestMailer, :action do
+  it "gets the mailer from the test name" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end
+
+describe TestTestMailer do
+  describe "nested" do
+    it "gets the mailer from the test name" do
+      assert_equal TestTestMailer, self.class.mailer_class
+    end
+  end
+end
+
+describe TestTestMailer, :action do
+  describe "nested" do
+    it "gets the mailer from the test name" do
+      assert_equal TestTestMailer, self.class.mailer_class
+    end
+  end
+end
+
+describe "TestTestMailer" do
+  it "gets the mailer from the test name" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end
+
+describe "TestTestMailerTest" do
+  it "gets the mailer from the test name" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end
+
+describe "TestTestMailer" do
+  describe "nested" do
+    it "gets the mailer from the test name" do
+      assert_equal TestTestMailer, self.class.mailer_class
+    end
+  end
+end
+
+describe "TestTestMailerTest" do
+  describe "nested" do
+    it "gets the mailer from the test name" do
+      assert_equal TestTestMailer, self.class.mailer_class
+    end
+  end
+end
+
+describe "AnotherCrazySymbolNameMailerTest" do
+  tests :test_test_mailer
+
+  it "gets the mailer after setting it with a symbol" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end
+
+describe "AnotherCrazyStringNameMailerTest" do
+  tests 'test_test_mailer'
+
+  it "gets the mailer after setting it with a string" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end
+
+describe "Another Crazy Name Mailer Test" do
+  tests TestTestMailer
+
+  it "gets the mailer after setting it manually" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end
+
+describe "Another Crazy Symbol Name Mailer Test" do
+  tests :test_test_mailer
+
+  it "gets the mailer after setting it with a symbol" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end
+
+describe "Another Crazy String Name Mailer Test" do
+  tests 'test_test_mailer'
+
+  it "gets the mailer after setting it with a string" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end
+
+describe "AnotherCrazySymbolNameMailerTest" do
+  tests :test_test_mailer
+
+  describe "nested" do
+    it "gets the mailer after setting it with a symbol" do
+      assert_equal TestTestMailer, self.class.mailer_class
+    end
+  end
+end
+
+describe "AnotherCrazyStringNameMailerTest" do
+  tests 'test_test_mailer'
+
+  describe "nested" do
+    it "gets the mailer after setting it with a string" do
+      assert_equal TestTestMailer, self.class.mailer_class
+    end
+  end
+end
+
+describe "Another Crazy Name Mailer Test" do
+  tests TestTestMailer
+
+  describe "nested" do
+    it "gets the mailer after setting it manually" do
+      assert_equal TestTestMailer, self.class.mailer_class
+    end
+  end
+end
+
+describe "Another Crazy Symbol Name Mailer Test" do
+  tests :test_test_mailer
+
+  describe "nested" do
+    it "gets the mailer after setting it with a symbol" do
+      assert_equal TestTestMailer, self.class.mailer_class
+    end
+  end
+end
+
+describe "Another Crazy String Name Mailer Test" do
+  tests 'test_test_mailer'
+
+  it "gets the mailer after setting it with a string" do
+    assert_equal TestTestMailer, self.class.mailer_class
+  end
+end