Add cmdjStruct to fill a struct passed by reference ##golang

* Add test example

go/r2pipe.go

@@ -203,11 +203,27 @@ func (r2p *Pipe) Cmdj(cmd string) (out interface{}, err error) {
 	return out, err
 }
 
+// CmdjStruct acts like Cmdjs but it will fill the interface/struct with the wanted values. It
+// returns the command execution error.
+func (r2p *Pipe) CmdjStruct(cmd string, out interface{}) (err error) {
+	rstr, err := r2p.Cmd(cmd)
+
+	if err == nil {
+		err = json.Unmarshal([]byte(rstr), out)
+	}
+	return err
+}
+
 //like cmdj but formats the command
 func (r2p *Pipe) Cmdjf(f string, args ...interface{}) (interface{}, error) {
 	return r2p.Cmdj(fmt.Sprintf(f, args...))
 }
 
+// like Cmdj, but besides format the command it will already fill the interface sent
+func (r2p *Pipe) CmdjfStruct(f string, out interface{}, args ...interface{}) error {
+	return r2p.CmdjStruct(fmt.Sprintf(f, args...), out)
+}
+
 // Close shuts down r2, closing the created pipe.
 func (r2p *Pipe) Close() error {
 	if r2p.close != nil {

go/r2pipe_test.go

@@ -2,8 +2,15 @@
 
 package r2pipe
 
-import "testing"
-import "fmt"
+import (
+	"fmt"
+	"testing"
+)
+
+type Offset struct {
+	Offset  uint
+	Current bool
+}
 
 func TestCmd(t *testing.T) {
 	fmt.Println("[*] Testing r2 spawn pipe")
@@ -26,4 +33,16 @@ func TestCmd(t *testing.T) {
 	if buf != check {
 		t.Errorf("buf=%v; want=%v", buf, check)
 	}
+
+	offset := Offset{}
+	r2p.CmdjStruct("sj ~{0}", &offset)
+
+	if !offset.Current {
+		t.Errorf("CurrentOffset=%v; want=%v", offset.Current, true)
+	}
+
+	r2p.CmdjfStruct("sj ~{%d}", &offset, 0)
+	if !offset.Current {
+		t.Errorf("CurrentOffset=%v; want=%v", offset.Current, true)
+	}
 }