Disable simplecov on travis-ci

MSP-11671

`bundler install --without coverage` will not install `simplecov`.
Running without simplecov changes the average runtime of `rake
cucumber:boot` from (n=13) 112.50 seconds to (n=10) 32.17 seconds
(-71.41%). (-73.68% from 2c1203ba49d49603aec169eed053ab929ccdedc6.)  Raw
data:
https://docs.google.com/spreadsheets/d/1vCRi_38Go3Wfq670eDCXMTSSXL1blSbk6NQsgpOqfYw/edit?usp=sharing.

.travis.yml

@@ -1,3 +1,4 @@
+bundler_env: --without coverage
 env:
   - RAKE_TASK=cucumber
   - RAKE_TASK=cucumber:boot

Gemfile

@@ -3,6 +3,14 @@ source 'https://rubygems.org'
 #   spec.add_runtime_dependency '<name>', [<version requirements>]
 gemspec name: 'metasploit-framework'
 
+# separate from test as simplecov is not run on travis-ci
+group :coverage do
+  # code coverage for tests
+  # any version newer than 0.5.4 gives an Encoding error when trying to read the source files.
+  # see: https://github.com/colszowka/simplecov/issues/127 (hopefully fixed in 0.8.0)
+  gem 'simplecov', '0.5.4', :require => false
+end
+
 group :db do
   gemspec name: 'metasploit-framework-db'
 end
@@ -44,10 +52,6 @@ group :test do
   # cucumber + automatic database cleaning with database_cleaner
   gem 'cucumber-rails', :require => false
   gem 'shoulda-matchers'
-  # code coverage for tests
-  # any version newer than 0.5.4 gives an Encoding error when trying to read the source files.
-  # see: https://github.com/colszowka/simplecov/issues/127 (hopefully fixed in 0.8.0)
-  gem 'simplecov', '0.5.4', :require => false
   # Manipulate Time.now in specs
   gem 'timecop'
 end

config/application.rb

@@ -9,6 +9,7 @@ all_environments = [
 
 Bundler.require(
     *Rails.groups(
+        coverage: [:test],
         db: all_environments,
         pcap: all_environments
     )

features/support/hooks.rb

@@ -4,23 +4,26 @@ Before do
   @aruba_timeout_seconds = 8.minutes
 end
 
-Before do |scenario|
-  command_name = case scenario
-                 when Cucumber::Ast::Scenario, Cucumber::Ast::ScenarioOutline
-                   "#{scenario.feature.title} #{scenario.name}"
-                 when Cucumber::Ast::OutlineTable::ExampleRow
-                   scenario_outline = scenario.scenario_outline
+# don't setup child processes to load simplecov_setup.rb if simplecov isn't installed
+unless Bundler.settings.without.include?(:coverage)
+  Before do |scenario|
+    command_name = case scenario
+                   when Cucumber::Ast::Scenario, Cucumber::Ast::ScenarioOutline
+                     "#{scenario.feature.title} #{scenario.name}"
+                   when Cucumber::Ast::OutlineTable::ExampleRow
+                     scenario_outline = scenario.scenario_outline
 
-                   "#{scenario_outline.feature.title} #{scenario_outline.name} #{scenario.name}"
-                 else
-                   raise TypeError, "Don't know how to extract command name from #{scenario.class}"
-                 end
+                     "#{scenario_outline.feature.title} #{scenario_outline.name} #{scenario.name}"
+                   else
+                     raise TypeError, "Don't know how to extract command name from #{scenario.class}"
+                   end
 
-  # Used in simplecov_setup so that each scenario has a different name and their coverage results are merged instead
-  # of overwriting each other as 'Cucumber Features'
-  set_env('SIMPLECOV_COMMAND_NAME', command_name)
+    # Used in simplecov_setup so that each scenario has a different name and their coverage results are merged instead
+    # of overwriting each other as 'Cucumber Features'
+    set_env('SIMPLECOV_COMMAND_NAME', command_name)
 
-  simplecov_setup_pathname = Pathname.new(__FILE__).expand_path.parent.join('simplecov_setup')
-  # set environment variable so child processes will merge their coverage data with parent process's coverage data.
-  set_env('RUBYOPT', "#{ENV['RUBYOPT']} -r#{simplecov_setup_pathname}")
+    simplecov_setup_pathname = Pathname.new(__FILE__).expand_path.parent.join('simplecov_setup')
+    # set environment variable so child processes will merge their coverage data with parent process's coverage data.
+    set_env('RUBYOPT', "#{ENV['RUBYOPT']} -r#{simplecov_setup_pathname}")
+  end
 end

features/support/simplecov_setup.rb

@@ -1,11 +1,16 @@
 # @note this file is loaded in env.rb to setup simplecov using RUBYOPTs for child processes
 
-require 'simplecov'
+simplecov_command_name = ENV['SIMPLECOV_COMMAND_NAME']
 
-require 'pathname'
+# will not be set if hook does not run because `bundle install --without coverage`
+if simplecov_command_name
+  require 'simplecov'
 
-root = Pathname(__FILE__).expand_path.parent.parent.parent
+  require 'pathname'
 
-SimpleCov.command_name(ENV['SIMPLECOV_COMMAND_NAME'])
-SimpleCov.root(root)
-load root.join('.simplecov')
+  root = Pathname(__FILE__).expand_path.parent.parent.parent
+
+  SimpleCov.command_name(simplecov_command_name)
+  SimpleCov.root(root)
+  load root.join('.simplecov')
+end

spec/spec_helper.rb

@@ -1,7 +1,9 @@
 # -*- coding: binary -*-
 ENV['RAILS_ENV'] = 'test'
 
-require 'simplecov'
+unless Bundler.settings.without.include?(:coverage)
+  require 'simplecov'
+end
 
 # @note must be before loading config/environment because railtie needs to be loaded before
 #   `Metasploit::Framework::Application.initialize!` is called.