raise an explicit exception when response does not include a JSON body (#520)

Author: agrobbin

lib/nylas/handler/http_client.rb

@@ -119,7 +119,7 @@ def default_headers
     def parse_response(response)
       return response if response.is_a?(Enumerable)
 
-      Yajl::Parser.new(symbolize_names: true).parse(response)
+      Yajl::Parser.new(symbolize_names: true).parse(response) || raise(Nylas::JsonParseError)
     rescue Yajl::ParseError
       raise Nylas::JsonParseError
     end

spec/nylas/handler/http_client_spec.rb

@@ -46,6 +46,12 @@ class TestHttpClient
 
       expect { http_client.send(:parse_response, response) }.to raise_error(Nylas::JsonParseError)
     end
+
+    it "raises an error if the response is empty" do
+      response = ""
+
+      expect { http_client.send(:parse_response, response) }.to raise_error(Nylas::JsonParseError)
+    end
   end
 
   describe "#build_request" do