Move max_redirects check into Response#return!

Previous refactoring would have broken the ability to call
`.follow_redirection` on a redirection response exception like
RestClient::Found. Instead, raise the exception at the time that the
response is first prepared.

lib/restclient/abstract_response.rb

@@ -82,11 +82,13 @@ module RestClient
       when 301, 302, 307
         case request.method
         when 'get', 'head'
+          check_max_redirects
           follow_redirection(&block)
         else
           raise exception_with_response
         end
       when 303
+        check_max_redirects
         follow_get_redirection(&block)
       else
         raise exception_with_response
@@ -178,9 +180,6 @@ module RestClient
       end
       new_args[:url] = url
 
-      if request.max_redirects <= 0
-        raise exception_with_response
-      end
       new_args[:password] = request.password
       new_args[:user] = request.user
       new_args[:headers] = request.headers
@@ -201,6 +200,12 @@ module RestClient
       new_req.execute(&block)
     end
 
+    def check_max_redirects
+      if request.max_redirects <= 0
+        raise exception_with_response
+      end
+    end
+
     def exception_with_response
       begin
         klass = Exceptions::EXCEPTIONS_MAP.fetch(code)

spec/unit/abstract_response_spec.rb

@@ -128,6 +128,7 @@ describe RestClient::AbstractResponse, :include_helpers do
 
     it "should follow 302 redirect" do
       @net_http_res.should_receive(:code).and_return('302')
+      @response.should_receive(:check_max_redirects).and_return('fake-check')
       @response.should_receive(:follow_redirection).and_return('fake-redirection')
       @response.return!.should eq 'fake-redirection'
     end
@@ -136,6 +137,7 @@ describe RestClient::AbstractResponse, :include_helpers do
       @net_http_res = response_double(code: 302, location: nil)
       @request = request_double()
       @response = MyAbstractResponse.new(@net_http_res, @request)
+      @response.should_receive(:check_max_redirects).and_return('fake-check')
       lambda { @response.return! }.should raise_error RestClient::Found
     end
   end

spec/unit/response_spec.rb

@@ -216,6 +216,22 @@ describe RestClient::Response, :include_helpers do
       }
       WebMock.should have_requested(:get, 'http://some/redirect-2').times(5)
     end
+
+    it "allows for manual following of redirects" do
+      stub_request(:get, 'http://some/redirect-1').to_return(:body => '', :status => 301, :headers => {'Location' => 'http://some/resource'})
+      stub_request(:get, 'http://some/resource').to_return(:body => 'Qux', :status => 200)
+
+      begin
+        RestClient::Request.execute(url: 'http://some/redirect-1', method: :get, max_redirects: 0)
+      rescue RestClient::MovedPermanently => err
+        resp = err.response.follow_redirection
+      else
+        raise 'notreached'
+      end
+
+      resp.code.should eq 200
+      resp.body.should eq 'Qux'
+    end
   end
 
 end