func CheckRemovePeer(c *C, op *operator.Operator, storeID uint64) {
	c.Assert(op, NotNil)
	if op.Len() == 1 {
		c.Assert(op.Step(0).(operator.RemovePeer).FromStore, Equals, storeID)
	} else {
		c.Assert(op.Len(), Equals, 2)
		c.Assert(op.Step(0).(operator.TransferLeader).FromStore, Equals, storeID)
		c.Assert(op.Step(1).(operator.RemovePeer).FromStore, Equals, storeID)
	}
}
CheckRemovePeer checks if the operator is to remove peer on specified store.
package testutil
import (
	. "github.com/pingcap/check"  
	"github.com/tikv/pd/server/schedule/operator"
)
func CheckAddPeer(c *C, op *operator.Operator, kind operator.OpKind, storeID uint64) {
	c.Assert(op, NotNil)
	c.Assert(op.Len(), Equals, 2)
	c.Assert(op.Step(0).(operator.AddLearner).ToStore, Equals, storeID)
	c.Assert(op.Step(1), FitsTypeOf, operator.PromoteLearner{})
	kind |= operator.OpRegion
	c.Assert(op.Kind()&kind, Equals, kind)
}