simplify pull logic

pkg/commands/oscommands/cmd_obj.go

@@ -0,0 +1,33 @@
+package oscommands
+
+import (
+	"os/exec"
+)
+
+// A command object is a general way to represent a command to be run on the
+// command line. If you want to log the command you'll use .ToString() and
+// if you want to run it you'll use .GetCmd()
+type ICmdObj interface {
+	GetCmd() *exec.Cmd
+	ToString() string
+	AddEnvVars(...string) ICmdObj
+}
+
+type CmdObj struct {
+	cmdStr string
+	cmd    *exec.Cmd
+}
+
+func (self *CmdObj) GetCmd() *exec.Cmd {
+	return self.cmd
+}
+
+func (self *CmdObj) ToString() string {
+	return self.cmdStr
+}
+
+func (self *CmdObj) AddEnvVars(vars ...string) ICmdObj {
+	self.cmd.Env = append(self.cmd.Env, vars...)
+
+	return self
+}