writer is called, its the telemetry that doesnt happen

Author: tlhunter

packages/dd-trace/test/exporters/agent/writer.spec.js

@@ -147,6 +147,23 @@ function describeWriter (protocolVersion) {
       })
     })
 
+    it('should log request errors', done => {
+      const error = new Error('boom')
+      error.status = 42
+
+      request.yields(error)
+
+      encoder.count.returns(1)
+      writer.flush()
+
+      setTimeout(() => {
+        expect(log.error)
+          .to.have.been.calledWith('Error sending payload to the agent (status code: %s)',
+            error.status, error, log.MUTE)
+        done()
+      })
+    })
+
     it('should update sampling rates', (done) => {
       encoder.count.returns(1)
       writer.flush(() => {