Fix tests so they run.

Index: test/run_tests.rb
--- test/run_tests.rb.orig
+++ test/run_tests.rb
@@ -32,9 +32,9 @@ Dir[arg].each {|f| fwidth = [fwidth, f.length + 10].ma
   html_file = file.sub('.text', '.html')
   opts_file = file.sub('.text', '.options')
   opts_file = File.join(File.dirname(file), 'options') unless File.exist?(opts_file)
-  options = File.exist?(opts_file) ? YAML.safe_load(File.read(opts_file)) : {auto_ids: false, footnote_nr: 1}
-  doc = Kramdown::Document.new(File.read(file), options)
   begin
+    options = File.exist?(opts_file) ? YAML.safe_load(File.read(opts_file)) : {auto_ids: false, footnote_nr: 1}
+    doc = Kramdown::Document.new(File.read(file), options)
     assert_equal(File.read(html_file), doc.to_html)
     puts 'PASSED'
   rescue StandardError
@@ -42,5 +42,5 @@ Dir[arg].each {|f| fwidth = [fwidth, f.length + 10].ma
     puts $!.message if $VERBOSE
     puts $!.backtrace if $DEBUG
   end
-  puts "Warnings:\n" + doc.warnings.join("\n") if !doc.warnings.empty? && $VERBOSE
+  puts "Warnings:\n" + doc.warnings.join("\n") if doc && !doc.warnings.empty? && $VERBOSE
 end