Prevent the file watcher from recursively enumerating into paths that it should ignore. This should fix the issue in #1197 as well as provide a performance boost when starting 'middleman server'.

middleman-core/lib/middleman-core/core_extensions/file_watcher.rb

@@ -7,12 +7,12 @@ module Middleman
     module FileWatcher
 
       IGNORE_LIST = [
-        /^bin\//,
-        /^\.bundle\//,
-        /^vendor\//,
-        /^\.sass-cache\//,
-        /^\.cache\//,
-        /^\.git\//,
+        /^bin(\/|$)/,
+        /^\.bundle(\/|$)/,
+        /^vendor(\/|$)/,
+        /^\.sass-cache(\/|$)/,
+        /^\.cache(\/|$)/,
+        /^\.git(\/|$)/,
         /^\.gitignore$/,
         /\.DS_Store/,
         /^\.rbenv-.*$/,
@@ -38,7 +38,7 @@ module Middleman
           end
 
           app.after_configuration do
-            config[:file_watcher_ignore] << %r{^#{config[:build_dir]}\/}
+            config[:file_watcher_ignore] << %r{^#{config[:build_dir]}(\/|$)}
           end
 
           # After config, load everything else
@@ -99,7 +99,6 @@ module Middleman
         # @return [void]
         def did_change(path)
           path = Pathname(path)
-          return if ignored?(path)
           logger.debug "== File Change: #{path}"
           @known_paths << path
           self.run_callbacks(path, :changed)
@@ -111,7 +110,6 @@ module Middleman
         # @return [void]
         def did_delete(path)
           path = Pathname(path)
-          return if ignored?(path)
           logger.debug "== File Deletion: #{path}"
           @known_paths.delete(path)
           self.run_callbacks(path, :deleted)
@@ -131,7 +129,7 @@ module Middleman
             glob = (path + '**').to_s
             subset = @known_paths.select { |p| p.fnmatch(glob) }
 
-            ::Middleman::Util.all_files_under(path).each do |filepath|
+            ::Middleman::Util.all_files_under(path, &method(:ignored?)).each do |filepath|
               next if only_new && subset.include?(filepath)
 
               subset.delete(filepath)
@@ -156,7 +154,6 @@ module Middleman
           @known_paths.include?(p)
         end
 
-      protected
         # Whether this path is ignored
         # @param [Pathname] path
         # @return [Boolean]
@@ -165,6 +162,8 @@ module Middleman
           app.config[:file_watcher_ignore].any? { |r| path =~ r }
         end
 
+      protected
+
         # Notify callbacks for a file given an array of callbacks
         #
         # @param [Pathname] path The file that was changed

middleman-core/lib/middleman-core/preview_server.rb

@@ -133,10 +133,12 @@ module Middleman
             @webrick.stop
           else
             added_and_modified.each do |path|
+              next if app.files.ignored?(path)
               app.files.did_change(path)
             end
 
             removed.each do |path|
+              next if app.files.ignored?(path)
               app.files.did_delete(path)
             end
           end

middleman-core/lib/middleman-core/util.rb

@@ -113,21 +113,27 @@ module Middleman
         end
       end
 
-      # Get a recusive list of files inside a set of paths.
+      # Get a recusive list of files inside a path.
       # Works with symlinks.
       #
-      # @param paths Some paths string or Pathname
-      # @return [Array] An array of filenames
-      def all_files_under(*paths)
-        paths.flat_map do |p|
-          path = Pathname(p)
+      # @param path Some path string or Pathname
+      # @param ignore A proc/block that returns true if a given path should be ignored - if a path
+      #               is ignored, nothing below it will be searched either.
+      # @return [Array<Pathname>] An array of Pathnames for each file (no directories)
+      def all_files_under(path, &ignore)
+        path = Pathname(path)
+
+        return [] if ignore && ignore.call(path)
 
         if path.directory?
-            all_files_under(*path.children)
-          elsif path.file?
-            path
-          end
+          path.children.flat_map do |child|
+            all_files_under(child, &ignore)
           end.compact
+        elsif path.file?
+          [path]
+        else
+          []
+        end
       end
 
       # Given a source path (referenced either absolutely or relatively)