Correct feedback, clarify order of precedence

lib/jekyll/commands/serve/servlet.rb

@@ -19,30 +19,30 @@ def initialize(server, root, callbacks)
         # Add the ability to tap file.html the same way that Nginx does on our
         # Docker images (or on GitHub Pages.) The difference is that we might end
         # up with a different preference on which comes first.
+        #
+        # Order of precedence:
+        # /file -> /file/index.html -> /file.html -> fancy-indexing -> 404.html
 
         def search_file(req, res, basename)
-          # /file.* -> /file.html
+          # First see if we can find /file normally, if not try /file.html
           super || super(req, res, "#{basename}.html")
         end
 
         def search_index_file(req, res)
-          # /file/index.html -> /file.html
-
-          # First, let's see if the our super method can figure it out.
-          # (i.e Check for index.html files in the res.filename directory)
+          # First, let's see if our super method can find an index file.
           file = super
 
           unless file
-            # Ok, I guess that didn't work, I guess there's no basename/index.html
-            # Let's look for basename.html instead...
+            # Ok, looks like there's no index file in the directory.
+            # Let's look for directory.html instead...
 
             # Split the basename from the path (res.filename)
             i = res.filename.rindex "\/"
             basename = res.filename[i..-1]
             res.filename = res.filename[0, i]
 
             # Try and find a file named dirname.html in the parent directory.
-            file = search_file(req, res, basename + ".html")
+            file = search_file(req, res, "#{basename}.html")
 
             # If we didn't find a file, revert our changes to res.filename.
             res.filename << basename unless file