Output inline is set to true in the plugin.

Change the reporter to just read the option.

Pass output_inline where needed in tests.

railties/lib/rails/test_unit/reporter.rb

@@ -49,7 +49,7 @@ def relative_path_for(file)
 
     private
       def output_inline?
-        options.fetch(:output_inline, true)
+        options[:output_inline]
       end
 
       def fail_fast?

railties/test/test_unit/reporter_test.rb

@@ -8,7 +8,7 @@ def woot; end
 
   setup do
     @output = StringIO.new
-    @reporter = Rails::TestUnitReporter.new @output
+    @reporter = Rails::TestUnitReporter.new @output, output_inline: true
   end
 
   test "prints rerun snippet to run a single failed test" do
@@ -72,7 +72,7 @@ def woot; end
   end
 
   test "outputs skipped tests inline if verbose" do
-    verbose = Rails::TestUnitReporter.new @output, verbose: true
+    verbose = Rails::TestUnitReporter.new @output, verbose: true, output_inline: true
     verbose.record(skipped_test)
     verbose.report