Add command: Reformat Document (⌃⇧H)

The new command “Reformat Document” formats the current document using
the `--auto-correct` option of [RuboCop][]. It also shows information
about the formatting status in a floating tooltip. The command displays
the information about the formatting status either as black text only,
or as colorful text if [aha][] is accessible via `$PATH`.

[aha]: https://github.com/theZiz/aha
[RuboCop]: https://github.com/bbatsov/rubocop

Commands/Reformat Document.tmCommand

@@ -0,0 +1,52 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>beforeRunningCommand</key>
+	<string>saveModifiedFiles</string>
+	<key>command</key>
+	<string>#!usr/bin/env ruby18
+
+# -- Imports -------------------------------------------------------------------
+
+require ENV['TM_BUNDLE_SUPPORT'] + '/lib/rubocop'
+
+# -- Main ----------------------------------------------------------------------
+
+RuboCop.reformat
+</string>
+	<key>input</key>
+	<string>document</string>
+	<key>inputFormat</key>
+	<string>text</string>
+	<key>keyEquivalent</key>
+	<string>^H</string>
+	<key>name</key>
+	<string>Reformat Document</string>
+	<key>outputCaret</key>
+	<string>heuristic</string>
+	<key>outputFormat</key>
+	<string>text</string>
+	<key>outputLocation</key>
+	<string>discard</string>
+	<key>requiredCommands</key>
+	<array>
+		<dict>
+			<key>command</key>
+			<string>rubocop</string>
+			<key>locations</key>
+			<array>
+				<string>/usr/local/bin/rubocop</string>
+				<string>$HOME/.rbenv/shims/rubocop</string>
+				<string>$HOME/.rvm/scripts/rvm</string>
+			</array>
+		</dict>
+	</array>
+	<key>scope</key>
+	<string>source.ruby</string>
+	<key>uuid</key>
+	<string>64BB4EE2-2803-410C-B140-EA545A13F250</string>
+	<key>version</key>
+	<integer>2</integer>
+</dict>
+</plist>

Support/lib/rubocop.rb

@@ -0,0 +1,82 @@
+# rubocop: disable AsciiComments
+# rubocop: disable Style/HashSyntax
+
+# -- Imports -------------------------------------------------------------------
+
+require ENV['TM_BUNDLE_SUPPORT'] + '/lib/executable'
+
+require ENV['TM_SUPPORT_PATH'] + '/lib/exit_codes'
+require ENV['TM_SUPPORT_PATH'] + '/lib/progress'
+require ENV['TM_SUPPORT_PATH'] + '/lib/tm/detach'
+require ENV['TM_SUPPORT_PATH'] + '/lib/tm/save_current_document'
+
+# -- Module --------------------------------------------------------------------
+
+# This module allows you to reformat files via RuboCop.
+module RuboCop
+  class << self
+    # This function reformats the current TextMate document using RuboCop.
+    #
+    # It works both on saved and unsaved files:
+    #
+    # 1. In the case of an unsaved files this method will stall until RuboCop
+    #    fixed the file. While this process takes place the method displays a
+    #    progress bar.
+    #
+    # 2. If the current document is a file saved somewhere on your disk, then
+    #    the method will not wait until RuboCop is finished. Instead it will run
+    #    RuboCop in the background. This has the advantage, that you can still
+    #    work inside TextMate, while RuboCop works on the document.
+    #
+    # After RuboCop finished reformatting the file, the method will inform you
+    # – via a tooltip – about the problems RuboCop found in the *previous*
+    # version of the document.
+    def reformat
+      unsaved_file = true unless ENV['TM_FILEPATH']
+      TextMate.save_if_untitled('rb')
+      format_file(locate_rubocop, unsaved_file)
+    end
+
+    private
+
+    def locate_rubocop
+      Dir.chdir(ENV['TM_PROJECT_DIRECTORY'] ||
+                File.dirname(ENV['TM_FILEPATH'].to_s))
+      begin
+        Executable.find('rubocop').join ' '
+      rescue Executable::NotFound => error
+        return 'rubocop' if File.executable?(`which rubocop`.rstrip)
+        TextMate.exit_show_tool_tip(error.message)
+      end
+    end
+
+    def format_file(rubocop, unsaved_file)
+      aha = `which aha`.rstrip.match(/.+/)
+      output_format = aha ? :html : :text
+      command = "#{rubocop} -a \"$TM_FILEPATH\" #{'--color | aha' if aha} 2>&1"
+      if unsaved_file
+        format_unsaved(command, output_format)
+      else
+        format_saved(command, output_format)
+      end
+    end
+
+    def format_unsaved(rubocop_command, output_format)
+      output, success = TextMate.call_with_progress(
+        :title => '🤖 RuboCop', :summary => 'Reformatting File'
+      ) do
+        [`#{rubocop_command}`, $CHILD_STATUS.success?]
+      end
+      TextMate.exit_show_tool_tip(output) unless success
+      TextMate::UI.tool_tip(output, :format => output_format)
+      TextMate.exit_replace_document(File.read(ENV['TM_FILEPATH']))
+    end
+
+    def format_saved(rubocop_command, output_format)
+      TextMate.detach do
+        output = `#{rubocop_command}`
+        TextMate::UI.tool_tip(output, :format => output_format)
+      end
+    end
+  end
+end

info.plist

@@ -31,6 +31,7 @@
 			<string>------------------------------------</string>
 			<string>8646378E-91F5-4771-AC7C-43FC49A93576</string>
 			<string>EE5F19BA-6C02-11D9-92BA-0011242E4184</string>
+			<string>64BB4EE2-2803-410C-B140-EA545A13F250</string>
 			<string>------------------------------------</string>
 			<string>EE5F1FB2-6C02-11D9-92BA-0011242E4184</string>
 			<string>FBFC214F-B019-4967-95D2-028F374A3221</string>