Land rapid7#3528, add Rubocop from @jhart-r7

This adds the gem to the :development group in the Gemfile, as well as
wires up msftidy to use it.

Author: Tod Beardsley

.rubocop.yml

@@ -0,0 +1,19 @@
+LineLength:
+  Enabled: true
+  Max: 180
+
+MethodLength:
+  Enabled: true
+  Max: 100
+
+Style/ClassLength:
+  Exclude:
+    # Most modules are quite large and all contained in one class.  This is OK.
+    - 'modules/**/*'
+
+Style/NumericLiterals:
+  Enabled: false
+
+Documentation:
+  Exclude:
+    - 'modules/**/*'

CONTRIBUTING.md

@@ -33,6 +33,7 @@ and Metasploit's [Common Coding Mistakes](https://github.com/rapid7/metasploit-f
 ## Code Contributions
 
 * **Do** stick to the [Ruby style guide](https://github.com/bbatsov/ruby-style-guide).
+* Similarly, **try** to get Rubocop passing or at least relatively quiet against the files added/modified as part of your contribution
 * **Do** follow the [50/72 rule](http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html) for Git commit messages.
 * **Do** create a [topic branch](http://git-scm.com/book/en/Git-Branching-Branching-Workflows#Topic-Branches) to work on instead of working directly on `master`.
 

Gemfile

@@ -37,6 +37,8 @@ group :pcap do
 end
 
 group :development do
+  # Style/sanity checking Ruby code
+  gem 'rubocop'
   # Markdown formatting for yard
   gem 'redcarpet'
   # generating documentation

Gemfile.lock

@@ -13,6 +13,7 @@ GEM
       i18n (~> 0.6, >= 0.6.4)
       multi_json (~> 1.0)
     arel (3.0.2)
+    ast (2.0.0)
     bcrypt (3.1.7)
     builder (3.0.4)
     database_cleaner (1.1.1)
@@ -34,8 +35,13 @@ GEM
     nokogiri (1.6.0)
       mini_portile (~> 0.5.0)
     packetfu (1.1.9)
+    parser (2.1.9)
+      ast (>= 1.1, < 3.0)
+      slop (~> 3.4, >= 3.4.5)
     pcaprub (0.11.3)
     pg (0.16.0)
+    powerpack (0.0.9)
+    rainbow (2.0.0)
     rake (10.1.0)
     redcarpet (3.0.0)
     rkelly-remix (0.0.6)
@@ -48,12 +54,20 @@ GEM
     rspec-expectations (2.14.2)
       diff-lcs (>= 1.1.3, < 2.0)
     rspec-mocks (2.14.3)
+    rubocop (0.23.0)
+      json (>= 1.7.7, < 2)
+      parser (~> 2.1.9)
+      powerpack (~> 0.0.6)
+      rainbow (>= 1.99.1, < 3.0)
+      ruby-progressbar (~> 1.4)
+    ruby-progressbar (1.5.1)
     shoulda-matchers (2.3.0)
       activesupport (>= 3.0.0)
     simplecov (0.5.4)
       multi_json (~> 1.0.3)
       simplecov-html (~> 0.5.3)
     simplecov-html (0.5.3)
+    slop (3.5.0)
     sqlite3 (1.3.9)
     timecop (0.6.3)
     tzinfo (0.3.37)
@@ -83,6 +97,7 @@ DEPENDENCIES
   rkelly-remix (= 0.0.6)
   robots
   rspec (>= 2.12)
+  rubocop
   shoulda-matchers
   simplecov (= 0.5.4)
   sqlite3

tools/msftidy.rb

@@ -320,6 +320,15 @@ def check_extname
     end
   end
 
+  # Explicitly skip this check if we're suppressing info messages
+  # anyway, since it takes a fair amount of time per module to perform.
+  def check_rubocop
+    return true if SUPPRESS_INFO_MESSAGES
+    out = %x{rubocop -n #{@full_filepath}}
+    ret = $?
+    info("Fails to pass Rubocop Ruby style guidelines (run 'rubocop #{@full_filepath}' to see violations)") unless ret.exitstatus == 0
+  end
+
   def check_old_rubies
     return true unless CHECK_OLD_RUBIES
     return true unless Object.const_defined? :RVM
@@ -574,6 +583,7 @@ def run_checks(full_filepath)
   tidy.check_vuln_codes
   tidy.check_vars_get
   tidy.check_newline_eof
+  tidy.check_rubocop
   return tidy
 end