move cmd output out of func.

cmd.go

@@ -93,16 +93,18 @@ func (c *Cmd) init() (err error) {
  return nil
 }
 
+// Command with context output.
+type ctxCmdOutput struct {
+ output []byte
+ err error
+}
+
 // Executes the given callback within session. Sends SIGINT when the context is canceled.
 func (c *Cmd) runWithContext(callback func() ([]byte, error)) ([]byte, error) {
- type commandOutput struct {
- output []byte
- err error
- }
- outputChan := make(chan commandOutput)
+ outputChan := make(chan ctxCmdOutput)
  go func() {
  output, err := callback()
- outputChan <- commandOutput{
+ outputChan <- ctxCmdOutput{
  output: output,
  err: err,
  }