Allow `Pry.config.editor` procs that take a `reloading` arg

This allow the user to implement an editor proc that only blocks the Pry
process if Pry is going to reload code when it returns:

    Pry.config.editor = proc do |file, line, reloading|
      "subl #{'--wait' if reloading} #{file}:#{line}"
    end

lib/pry/config.rb

@@ -116,13 +116,17 @@ class Pry
     # for the platform.
     # If `editor` is a String then that string is used as the shell
     # command to invoke the editor. If `editor` is callable (e.g a
-    # Proc) then `file` and `line` are passed in as parameters and the
+    # Proc) then `file`, `line`, and `reloading` are passed in as parameters and the
     # return value of that callable invocation is used as the exact
-    # shell command to invoke the editor.
+    # shell command to invoke the editor. `reloading` indicates whether Pry will be
+    # reloading code after the shell command returns. Any or all of these parameters
+    # can be omitted from the callable's signature.
     # @example String
     #   Pry.config.editor = "emacsclient"
     # @example Callable
     #   Pry.config.editor = proc { |file, line| "emacsclient #{file} +#{line}" }
+    # @example Callable waiting only if reloading
+    #   Pry.config.editor = proc { |file, line, reloading| "subl #{'--wait' if reloading} #{file}:#{line}" }
     # @return [String, #call]
     attr_accessor :editor
 

lib/pry/default_commands/editing.rb

@@ -88,8 +88,9 @@ class Pry
           temp_file do |f|
             f.puts(content)
             f.flush
-            invoke_editor(f.path, line)
-            if !opts.present?(:'no-reload') && !Pry.config.disable_auto_reload
+            reload = !opts.present?(:'no-reload') && !Pry.config.disable_auto_reload
+            invoke_editor(f.path, line, reload)
+            if reload
               silence_warnings do
                 eval_string.replace(File.read(f.path))
               end
@@ -138,10 +139,11 @@ class Pry
 
           line = opts[:l].to_i if opts.present?(:line)
 
-          invoke_editor(file_name, line)
+          reload = opts.present?(:reload) || ((opts.present?(:ex) || file_name.end_with?(".rb")) && !opts.present?(:'no-reload')) && !Pry.config.disable_auto_reload
+          invoke_editor(file_name, line, reload)
           set_file_and_dir_locals(file_name)
 
-          if opts.present?(:reload) || ((opts.present?(:ex) || file_name.end_with?(".rb")) && !opts.present?(:'no-reload')) && !Pry.config.disable_auto_reload
+          if reload
             silence_warnings do
               TOPLEVEL_BINDING.eval(File.read(file_name), file_name)
             end
@@ -207,7 +209,7 @@ class Pry
           temp_file do |f|
             f.puts lines.join
             f.flush
-            invoke_editor(f.path, 0)
+            invoke_editor(f.path, 0, true)
 
             if @method.alias?
               with_method_transaction(original_name, @method.owner) do
@@ -223,9 +225,10 @@ class Pry
         def process_file
           file, line = extract_file_and_line
 
-          invoke_editor(file, opts["no-jump"] ? 0 : line)
+          reload = !opts.present?(:'no-reload') && !Pry.config.disable_auto_reload
+          invoke_editor(file, opts["no-jump"] ? 0 : line, reload)
           silence_warnings do
-            load file unless opts.present?(:'no-reload') || Pry.config.disable_auto_reload
+            load file if reload
           end
         end
 

lib/pry/helpers/command_helpers.rb

@@ -113,10 +113,11 @@ class Pry
         process_yardoc process_rdoc(comment, code_type)
       end
 
-      def invoke_editor(file, line)
+      def invoke_editor(file, line, reloading)
         raise CommandError, "Please set Pry.config.editor or export $VISUAL or $EDITOR" unless Pry.config.editor
         if Pry.config.editor.respond_to?(:call)
-          editor_invocation = Pry.config.editor.call(file, line)
+          args = [file, line, reloading][0...(Pry.config.editor.arity)]
+          editor_invocation = Pry.config.editor.call(*args)
         else
           editor_invocation = "#{Pry.config.editor} #{start_line_syntax_for_editor(file, line)}"
         end

test/test_default_commands/test_introspection.rb

@@ -83,6 +83,23 @@ describe "Pry::DefaultCommands::Introspection" do
           tf.close(true)
         end
       end
+
+      describe do
+        before do
+          @reloading = nil
+          Pry.config.editor = lambda do |file, line, reloading|
+            @file = file; @line = line; @reloading = reloading
+            nil
+          end
+        end
+
+        it "should pass the editor a reloading arg" do
+          mock_pry("edit foo.rb")
+          @reloading.should == true
+          mock_pry("edit -n foo.rb")
+          @reloading.should == false
+        end
+      end
     end
 
     describe "with --ex" do
@@ -610,6 +627,28 @@ describe "Pry::DefaultCommands::Introspection" do
           X.new.c.should == :kindaaa
         end
       end
+
+      describe 'with three-arg editor' do
+        before do
+          @old_editor = Pry.config.editor
+          @file, @line, @reloading = nil, nil, nil
+          Pry.config.editor = lambda do |file, line, reloading|
+            @file = file; @line = line; @reloading = reloading
+            nil
+          end
+        end
+        after do
+          Pry.config.editor = @old_editor
+        end
+
+        it "should pass the editor a reloading arg" do
+          mock_pry('edit-method X.x')
+          @reloading.should == true
+          mock_pry('edit-method -n X.x')
+          @reloading.should == false
+        end
+      end
+
     end
   end