Response not getting cached when using .Bytes() or .String() methods

[HittingSmoke]

I read the response quirks on the readme but have so far been unable to get a struct populated using the response.JSON() method.

I'm using the latest version of grequests with Go 1.11. Here is the chunk of code in question:

        resp, _ := session.Post(loginapi, ro)

	fmt.Println(resp.Bytes())
	fmt.Println(resp.String()) // S1
	fmt.Println(resp.StatusCode)

	var r = new(APIResponse)

	fmt.Println(resp.JSON(&r))
	fmt.Println(resp.String()) // S2

In this scenario, S1 will print the response string and S2 will be empty. If I remove the resp.JSON() line everything works fine. Even if I try to call resp.JSON() first to populate before any other response method calls, the struct comes back nil.

[MarkusFreitag]

Please note that resp.JSON does return an error instead of your filled data struct. That is the reason, why you need to provide a pointer to it. So if resp.JSON returns nil no error occurred while unmarshaling the json string.

Code:

package main

import (
  "fmt"

  "github.com/levigross/grequests"
)

type jsonResponse struct {
  Message string `json:"message"`
}

func main() {
  resp, _ := grequests.Get("http://127.0.0.1:8080/", nil)
  fmt.Println("before resp.JSON")
  fmt.Printf("resp.Bytes() => %v\n", resp.Bytes())
  fmt.Printf("resp.String() => %v\n", resp.String())
  fmt.Printf("resp.StatusCode => %d\n\n", resp.StatusCode)

  var r = new(jsonResponse)
  resp.JSON(&r)
  fmt.Println("after resp.JSON")
  fmt.Printf("json struct => %v\n", r)
  fmt.Printf("resp.Bytes() => %v\n", resp.Bytes())
  fmt.Printf("resp.String() => %v\n", resp.String())
  fmt.Printf("resp.StatusCode => %d\n", resp.StatusCode)
}

Output:

before resp.JSON
resp.Bytes() => [123 34 109 101 115 115 97 103 101 34 58 34 109 111 111 34 125]
resp.String() => {"message":"moo"}
resp.StatusCode => 200

after resp.JSON
json struct => &main.jsonResponse{Message:"moo"}
resp.Bytes() => []
resp.String() => 
resp.StatusCode => 200