Fix string substitution regression

[nicoco007]

Some of our tests started failing when updating from version 2.0.3. After some investigation, it turns out this change from #76 is the culprit – quotation marks are no longer escaped if the substitution value is a string since inspect isn't being called anymore. Reverting the change isn't possible since it would break some regular expressions so I've just added an exception here for strings.

[flavorjones]

Would you consider fixing this instead by carving out an exception for Regexes (which is what #76 probably should have done)?

--- a/lib/rails/dom/testing/assertions/selector_assertions/substitution_context.rb
+++ b/lib/rails/dom/testing/assertions/selector_assertions/substitution_context.rb
@@ -19,10 +19,12 @@ def match(matches, attribute, matcher)
   private
     def matcher_for(value, format_for_presentation)
       # Nokogiri doesn't like arbitrary values without quotes, hence inspect.
       if format_for_presentation
         value.inspect # Avoid to_s so Regexps aren't put in quotes.
-      else
+      elsif value.is_a?(Regexp)
         "\"#{value}\""
+      else
+        value.to_s.inspect
       end
     end

[nicoco007]

Looks like Rafael beat me to the punch 😅 Yeah that makes more sense!