Add termination-estimate to get an estimation for how much a termination penalty will be:

- Usage example: `./lotus-shed sectors termation-estimate 5 8 10`.

cmd/lotus-shed/sectors.go

@@ -25,6 +25,7 @@ var sectorsCmd = &cli.Command{
 	Flags: []cli.Flag{},
 	Subcommands: []*cli.Command{
 		terminateSectorCmd,
+		terminateSectorPenaltyEstimationCmd,
 	},
 }
 
@@ -131,3 +132,101 @@ var terminateSectorCmd = &cli.Command{
 		return nil
 	},
 }
+
+func findPenaltyInInternalExecutions(prefix string, trace []types.ExecutionTrace) {
+	for _, im := range trace {
+		if im.Msg.To.String() == "f099" /*Burn actor*/ {
+			fmt.Printf("Estimated termination penalty: %s attoFIL\n", im.Msg.Value)
+			return
+		}
+		findPenaltyInInternalExecutions(prefix+"\t", im.Subcalls)
+	}
+}
+
+var terminateSectorPenaltyEstimationCmd = &cli.Command{
+	Name:      "termination-estimate",
+	Usage:     "Estimate the termination penalty",
+	ArgsUsage: "[sectorNum1 sectorNum2 ...]",
+	Action: func(cctx *cli.Context) error {
+		if cctx.Args().Len() < 1 {
+			return fmt.Errorf("at least one sector must be specified")
+		}
+
+		nodeApi, closer, err := lcli.GetFullNodeAPI(cctx)
+		if err != nil {
+			return err
+		}
+		defer closer()
+
+		api, acloser, err := lcli.GetStorageMinerAPI(cctx)
+		if err != nil {
+			return err
+		}
+		defer acloser()
+
+		ctx := lcli.ReqContext(cctx)
+
+		maddr, err := api.ActorAddress(ctx)
+		if err != nil {
+			return err
+		}
+
+		mi, err := nodeApi.StateMinerInfo(ctx, maddr, types.EmptyTSK)
+		if err != nil {
+			return err
+		}
+
+		terminationDeclarationParams := []miner2.TerminationDeclaration{}
+
+		for _, sn := range cctx.Args().Slice() {
+			sectorNum, err := strconv.ParseUint(sn, 10, 64)
+			if err != nil {
+				return fmt.Errorf("could not parse sector number: %w", err)
+			}
+
+			sectorbit := bitfield.New()
+			sectorbit.Set(sectorNum)
+
+			loca, err := nodeApi.StateSectorPartition(ctx, maddr, abi.SectorNumber(sectorNum), types.EmptyTSK)
+			if err != nil {
+				return fmt.Errorf("get state sector partition %s", err)
+			}
+
+			para := miner2.TerminationDeclaration{
+				Deadline:  loca.Deadline,
+				Partition: loca.Partition,
+				Sectors:   sectorbit,
+			}
+
+			terminationDeclarationParams = append(terminationDeclarationParams, para)
+		}
+
+		terminateSectorParams := &miner2.TerminateSectorsParams{
+			Terminations: terminationDeclarationParams,
+		}
+
+		sp, err := actors.SerializeParams(terminateSectorParams)
+		if err != nil {
+			return xerrors.Errorf("serializing params: %w", err)
+		}
+
+		msg := &types.Message{
+			From:   mi.Owner,
+			To:     maddr,
+			Method: miner.Methods.TerminateSectors,
+
+			Value:  big.Zero(),
+			Params: sp,
+		}
+
+		//TODO: 4667 add an option to give a more precise estimation with pending termination penalty excluded
+
+		invocResult, err := nodeApi.StateCall(ctx, msg, types.TipSetKey{})
+		if err != nil {
+			return xerrors.Errorf("fail to state call: %w", err)
+		}
+
+		findPenaltyInInternalExecutions("\t", invocResult.ExecutionTrace.Subcalls)
+		return nil
+	},
+}