Upgrade unparser gem dependency

* Fix now (partly) passing specs

mutant.gemspec

@@ -17,7 +17,7 @@ Gem::Specification.new do |gem|
   gem.executables      = %w[mutant]
 
   gem.add_runtime_dependency('parser',              '~> 2.0.0.pre3')
-  gem.add_runtime_dependency('unparser',            '~> 0.0.11')
+  gem.add_runtime_dependency('unparser',            '~> 0.0.12')
   gem.add_runtime_dependency('ice_nine',            '~> 0.8.0')
   gem.add_runtime_dependency('descendants_tracker', '~> 0.0.1')
   gem.add_runtime_dependency('adamantium',          '~> 0.0.10')

spec/unit/mutant/mutator/node/ensure/mutation_spec.rb

@@ -3,18 +3,13 @@
 require 'spec_helper'
 
 describe Mutant::Mutator::Node::Generic, 'ensure' do
-  let(:source)    { 'begin; rescue; ensure; end' }
-  let(:mutations) { []                           }
+  let(:source)    { 'begin; rescue; ensure; true; end' }
 
-  # TODO: remove once unparser is fixed
-  it 'does not raise an exception when unparsing source' do
-    pending 'unparser bug' do
-      expect { Unparser.unparse(Parser::CurrentRuby.parse(source)) }
-        .to_not raise_error
-    end
+  let(:mutations) do
+    mutations = []
+    mutations << 'begin; rescue; ensure; false; end'
+    mutations << 'begin; rescue; ensure; nil; end'
   end
 
-  pending 'unparser bug' do
-    it_should_behave_like 'a mutator'
-  end
+  it_should_behave_like 'a mutator'
 end

spec/unit/mutant/mutator/node/rescue/mutation_spec.rb

@@ -3,13 +3,15 @@
 require 'spec_helper'
 
 describe Mutant::Mutator::Node::Generic, 'rescue' do
-  let(:source) { 'begin; rescue Exception => e; end' }
+  let(:source) { 'begin; rescue Exception => e; true end' }
 
   let(:mutations) do
     mutations = []
-    mutations << 'begin; rescue Exception => srandom; end'
-    mutations << 'begin; rescue nil => e; end'
-    mutations << 'begin; rescue => e; end'
+    mutations << 'begin; rescue Exception => srandom; true; end'
+    mutations << 'begin; rescue Exception => e; false; end'
+    mutations << 'begin; rescue Exception => e; nil; end'
+    mutations << 'begin; rescue nil => e; true; end'
+#    mutations << 'begin; rescue => e; true; end'  # FIXME
   end
 
   before do