add suid sgid and sticky support for file resource

inspec.gemspec

@@ -24,7 +24,7 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
   spec.require_paths = ['lib']
 
-  spec.add_dependency 'train', '~> 0.13'
+  spec.add_dependency 'train', '>=0.15.1', '<1.0'
   spec.add_dependency 'thor', '~> 0.19'
   spec.add_dependency 'json', '~> 1.8'
   spec.add_dependency 'rainbow', '~> 2'

lib/resources/file.rb

@@ -91,6 +91,18 @@ module Inspec::Resources
       end
     end
 
+    def suid
+      (mode & 04000) > 0
+    end
+
+    def sgid
+      (mode & 02000) > 0
+    end
+
+    def sticky
+      (mode & 01000) > 0
+    end
+
     def to_s
       "File #{source_path}"
     end

test/cookbooks/os_prepare/recipes/file.rb

@@ -25,6 +25,13 @@ if node['platform_family'] != 'windows'
     content 'hello world'
   end
 
+  file '/tmp/sfile' do
+    mode '7765'
+    owner 'root'
+    group gid
+    content 'hello suid/sgid/sticky'
+  end
+
   directory '/tmp/folder' do
     mode '0567'
     owner 'root'

test/integration/default/file_spec.rb

@@ -61,6 +61,9 @@ if os.unix?
     it { should be_mode 00765 }
     its('mode') { should cmp 0765 }
     its('mode') { should_not cmp 0777 }
+    its('suid') { should eq false }
+    its('sgid') { should eq false }
+    its('sticky') { should eq false }
 
     it { should be_readable }
     it { should be_readable.by('owner') }
@@ -107,6 +110,12 @@ if os.unix?
     its('type') { should eq :file }
   end
 
+  describe file('/tmp/file') do
+    its('suid') { should eq true }
+    its('sgid') { should eq true }
+    its('sticky') { should eq true }
+  end
+
   describe file('/tmp/folder') do
     it { should exist }
     it { should be_directory }