Deprecate `MissingSourceFile` in favor of `LoadError`.

`MissingSourceFile` was just an alias to `LoadError` and was not
being raised inside the framework.

1 files changed, 9 insertions, 0 deletions

diff --git a/activesupport/test/core_ext/load_error_test.rb b/activesupport/test/core_ext/load_error_test.rb
index 66c39b143c..b2a75a2bcc 100644
--- a/activesupport/test/core_ext/load_error_test.rb
+++ b/activesupport/test/core_ext/load_error_test.rb
@@ -1,6 +1,15 @@
 require 'abstract_unit'
 require 'active_support/core_ext/load_error'
 
+
+class TestMissingSourceFile < ActiveSupport::TestCase
+  def test_it_is_deprecated
+    assert_deprecated do
+      MissingSourceFile.new
+    end
+  end
+end
+
 class TestLoadError < ActiveSupport::TestCase
   def test_with_require
     assert_raise(LoadError) { require 'no_this_file_don\'t_exist' }