Usage file in generators shouldn't be fetched only based on source_root

In case `source_roout` is not set, `default_source_root` is used,
which includes also `templates` directory. If there is no `templates`
directory, `default_source_root` is not available and USAGE will not
be displayed. USAGE should be also checked based on default
directory excluding `templates`.

2 files changed, 5 insertions, 1 deletions

diff --git a/railties/test/generators/app_generator_test.rb b/railties/test/generators/app_generator_test.rb
index d8887a6471..128854e4ad 100644
--- a/railties/test/generators/app_generator_test.rb
+++ b/railties/test/generators/app_generator_test.rb
@@ -302,7 +302,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_default_usage
-    File.expects(:exist?).returns(false)
+    Rails::Generators::AppGenerator.expects(:usage_path).returns(nil)
     assert_match(/Create rails files for app generator/, Rails::Generators::AppGenerator.desc)
   end
 
diff --git a/railties/test/generators/migration_generator_test.rb b/railties/test/generators/migration_generator_test.rb
index fd84164340..b320e40654 100644
--- a/railties/test/generators/migration_generator_test.rb
+++ b/railties/test/generators/migration_generator_test.rb
@@ -152,4 +152,8 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
       end
     end
   end
+
+  def test_properly_identifies_usage_file
+    assert generator_class.send(:usage_path)
+  end
 end