cli: add 'jump' command

Close #2606.

cli/vm/cli.go

@@ -92,6 +92,15 @@ var commands = []cli.Command{
 > break 12`,
 		Action: handleBreak,
 	},
+	{
+		Name:      "jump",
+		Usage:     "Jump to the specified instruction (absolute IP value)",
+		UsageText: `jump <ip>`,
+		Description: `jump <ip>
+<ip> is mandatory parameter, example:
+> jump 12`,
+		Action: handleJump,
+	},
 	{
 		Name:        "estack",
 		Usage:       "Show evaluation stack contents",
@@ -559,21 +568,44 @@ func handleBreak(c *cli.Context) error {
 	if !checkVMIsReady(c.App) {
 		return nil
 	}
-	v := getVMFromContext(c.App)
+	n, err := getInstructionParameter(c)
-	args := c.Args()
-	if len(args) != 1 {
-		return fmt.Errorf("%w: <ip>", ErrMissingParameter)
-	}
-	n, err := strconv.Atoi(args[0])
 	if err != nil {
-		return fmt.Errorf("%w: %s", ErrInvalidParameter, err)
+		return err
 	}
 
+	v := getVMFromContext(c.App)
 	v.AddBreakPoint(n)
 	fmt.Fprintf(c.App.Writer, "breakpoint added at instruction %d\n", n)
 	return nil
 }
 
+func handleJump(c *cli.Context) error {
+	if !checkVMIsReady(c.App) {
+		return nil
+	}
+	n, err := getInstructionParameter(c)
+	if err != nil {
+		return err
+	}
+
+	v := getVMFromContext(c.App)
+	v.Context().Jump(n)
+	fmt.Fprintf(c.App.Writer, "jumped to instruction %d\n", n)
+	return nil
+}
+
+func getInstructionParameter(c *cli.Context) (int, error) {
+	args := c.Args()
+	if len(args) != 1 {
+		return 0, fmt.Errorf("%w: <ip>", ErrMissingParameter)
+	}
+	n, err := strconv.Atoi(args[0])
+	if err != nil {
+		return 0, fmt.Errorf("%w: %s", ErrInvalidParameter, err)
+	}
+	return n, nil
+}
+
 func handleXStack(c *cli.Context) error {
 	v := getVMFromContext(c.App)
 	var stackDump string

cli/vm/cli_test.go

@@ -11,6 +11,7 @@ import (
 	"math/big"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"sync"
 	"testing"
@@ -1181,3 +1182,20 @@ func TestLoaddeployed(t *testing.T) {
 	e.checkStack(t, false)
 	e.checkError(t, errors.New("contract hash, address or ID is mandatory argument"))
 }
+
+func TestJump(t *testing.T) {
+	buf := io.NewBufBinWriter()
+	emit.Opcodes(buf.BinWriter, opcode.PUSH1, opcode.PUSH2, opcode.ABORT) // some garbage
+	jmpTo := buf.Len()
+	emit.Opcodes(buf.BinWriter, opcode.PUSH4, opcode.PUSH5, opcode.ADD) // useful script
+	e := newTestVMCLI(t)
+	e.runProg(t,
+		"loadhex "+hex.EncodeToString(buf.Bytes()),
+		"jump "+strconv.Itoa(jmpTo),
+		"run",
+	)
+
+	e.checkNextLine(t, "READY: loaded 6 instructions")
+	e.checkNextLine(t, fmt.Sprintf("jumped to instruction %d", jmpTo))
+	e.checkStack(t, 9)
+}