Fix rake task and add test for it

Change-Id: Idc7564816b430066672a624301390937e55d3c81
Reviewed-on: http://gerrit.causes.com/45246
Tested-by: jenkins <[email protected]>
Reviewed-by: Shane da Silva <[email protected]>

Author: alex-slynko

lib/scss_lint/rake_task.rb

@@ -29,10 +29,7 @@ def run_task
       require 'scss_lint'
       require 'scss_lint/cli'
 
-      CLI.new([]).tap do |cli|
-        cli.parse_arguments
-        cli.run
-      end
+      CLI.new.run([])
     rescue SystemExit => ex
       if ex.status == CLI::EXIT_CODES[:data]
         abort('scss-lint found lints')

spec/scss_lint/rake_task_spec.rb

@@ -0,0 +1,20 @@
+require 'spec_helper'
+require 'scss_lint/rake_task'
+
+describe SCSSLint::RakeTask do
+  before do
+    # Silence console output
+    STDOUT.stub(:write)
+  end
+
+  describe '#run' do
+    subject do
+      SCSSLint::RakeTask.new
+      Rake::Task['scss_lint']
+    end
+
+    it 'returns a successful exit code' do
+      expect(subject.invoke.first.call).to be_truthy
+    end
+  end
+end