Avoid confusing Typhoeus.stub with RSpec's #stub

This fixes #4.

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Master
 
+* Avoid confusing `Typhoeus.stub` with RSpec's `stub` ([#4](https://github.com/yujinakayama/transpec/issues/4))
+
 ## v0.0.6
 
 * Fix a bug where `SomeClass.any_instance.should_receive(:message).any_number_of_times` was converted into `expect_any_instance_of(SomeClass).to receive(:message)` unintentionally (now it's converted into `allow_any_instance_of(SomeClass).to receive(:message)`)

lib/transpec/syntax/method_stub.rb

@@ -11,6 +11,8 @@ class Syntax
     class MethodStub < Syntax
       include AnyInstanceable, AnyNumberOfTimesable, Util
 
+      RECEIVER_CLASS_WHITELIST = ['Typhoeus']
+
       def allowize!
         # There's no way of unstubbing in #allow syntax.
         return unless [:stub, :stub!].include?(method_name)
@@ -50,7 +52,9 @@ def replace_deprecated_method!
       private
 
       def self.target_receiver_node?(node)
-        !node.nil?
+        return false if node.nil?
+        const_name = Util.const_name(node)
+        !RECEIVER_CLASS_WHITELIST.include?(const_name)
       end
 
       def self.target_method_names

spec/support/ast_helper.rb

@@ -0,0 +1,15 @@
+# encoding: utf-8
+
+module ASTHelper
+  def scan_node(node, options = {}, &block)
+    yield node if options[:include_origin_node]
+
+    node.children.each do |child|
+      next unless child.is_a?(Parser::AST::Node)
+      yield child
+      scan_node(child, &block)
+    end
+
+    nil
+  end
+end

spec/transpec/syntax/method_stub_spec.rb

@@ -23,6 +23,46 @@ class Syntax
 
       let(:in_example_group_context?) { true }
 
+      describe '.target_node?' do
+        include ASTHelper
+
+        let(:send_node) do
+          scan_node(ast, include_origin_node: true) do |node|
+            next unless node.type == :send
+            method_name = node.children[1]
+            next unless method_name == :stub
+            return node
+          end
+          fail 'No #stub node is found!'
+        end
+
+        context 'when #stub node is passed' do
+          let(:source) do
+            <<-END
+              it 'responds to #foo' do
+                subject.stub(:foo)
+              end
+            END
+          end
+
+          it 'returns true' do
+            MethodStub.target_node?(send_node).should be_true
+          end
+        end
+
+        context 'when #stub node with Typhoeus receiver is passed' do
+          let(:source) do
+            <<-END
+              ::Typhoeus.stub(url, :method => method).and_return(response)
+            END
+          end
+
+          it 'returns false' do
+            MethodStub.target_node?(send_node).should be_false
+          end
+        end
+      end
+
       describe '#method_name' do
         let(:source) do
           <<-END