Merge pull request #3020 from nspcc-dev/loadnef-enh-2

cli: properly load specified method for `run` VM CLI command

cli/vm/cli.go

@@ -28,12 +28,14 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
 	"github.com/nspcc-dev/neo-go/pkg/core/native"
+	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage/dbconfig"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/encoding/address"
 	"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/nef"
@@ -51,7 +53,7 @@ const (
 	chainKey            = "chain"
 	chainCfgKey         = "chainCfg"
 	icKey               = "ic"
-	manifestKey         = "manifest"
+	contractStateKey    = "contractState"
 	exitFuncKey         = "exitFunc"
 	readlineInstanceKey = "readlineKey"
 	printLogoKey        = "printLogoKey"
@@ -64,6 +66,7 @@ const (
 	gasFlagFullName       = "gas"
 	backwardsFlagFullName = "backwards"
 	diffFlagFullName      = "diff"
+	hashFlagFullName      = "hash"
 )
 
 var (
@@ -76,6 +79,10 @@ var (
 		Name:  gasFlagFullName,
 		Usage: "GAS limit for this execution (integer number, satoshi).",
 	}
+	hashFlag = cli.StringFlag{
+		Name:  hashFlagFullName,
+		Usage: "Smart-contract hash in LE form or address",
+	}
 )
 
 var commands = []cli.Command{
@@ -150,9 +157,9 @@ Example:
 	},
 	{
 		Name:      "loadnef",
-		Usage:     "Load a NEF-consistent script into the VM optionally attaching to it provided signers with scopes",
+		Usage:     "Load a NEF (possibly with a contract hash) into the VM optionally using provided scoped signers in the context",
-		UsageText: `loadnef [--historic <height>] [--gas <int>] <file> [<manifest>] [-- <signer-with-scope>, ...]`,
+		UsageText: `loadnef [--historic <height>] [--gas <int>] [--hash <hash-or-address>] <file> [<manifest>] [-- <signer-with-scope>, ...]`,
-		Flags:     []cli.Flag{historicFlag, gasFlag},
+		Flags:     []cli.Flag{historicFlag, gasFlag, hashFlag},
 		Description: `<file> parameter is mandatory, <manifest> parameter (if omitted) will
    be guessed from the <file> parameter by replacing '.nef' suffix with '.manifest.json'
    suffix.
@@ -191,9 +198,9 @@ Example:
 	},
 	{
 		Name:      "loadgo",
-		Usage:     "Compile and load a Go file with the manifest into the VM optionally attaching to it provided signers with scopes",
+		Usage:     "Compile and load a Go file with the manifest into the VM optionally attaching to it provided signers with scopes and setting provided hash",
-		UsageText: `loadgo [--historic <height>] [--gas <int>] <file> [-- <signer-with-scope>, ...]`,
+		UsageText: `loadgo [--historic <height>] [--gas <int>] [--hash <hash-or-address>] <file> [-- <signer-with-scope>, ...]`,
-		Flags:     []cli.Flag{historicFlag, gasFlag},
+		Flags:     []cli.Flag{historicFlag, gasFlag, hashFlag},
 		Description: `<file> is mandatory parameter.
 
 ` + cmdargs.SignersParsingDoc + `
@@ -489,7 +496,7 @@ func NewWithConfig(printLogotype bool, onExit func(int), c *readline.Config, cfg
 		chainKey:            chain,
 		chainCfgKey:         cfg,
 		icKey:               ic,
-		manifestKey:         new(manifest.Manifest),
+		contractStateKey:    new(state.ContractBase),
 		exitFuncKey:         exitF,
 		readlineInstanceKey: l,
 		printLogoKey:        printLogotype,
@@ -522,8 +529,8 @@ func getInteropContextFromContext(app *cli.App) *interop.Context {
 	return app.Metadata[icKey].(*interop.Context)
 }
 
-func getManifestFromContext(app *cli.App) *manifest.Manifest {
+func getContractStateFromContext(app *cli.App) *state.ContractBase {
-	return app.Metadata[manifestKey].(*manifest.Manifest)
+	return app.Metadata[contractStateKey].(*state.ContractBase)
 }
 
 func getPrintLogoFromContext(app *cli.App) bool {
@@ -534,8 +541,8 @@ func setInteropContextInContext(app *cli.App, ic *interop.Context) {
 	app.Metadata[icKey] = ic
 }
 
-func setManifestInContext(app *cli.App, m *manifest.Manifest) {
+func setContractStateInContext(app *cli.App, cs *state.ContractBase) {
-	app.Metadata[manifestKey] = m
+	app.Metadata[contractStateKey] = cs
 }
 
 func checkVMIsReady(app *cli.App) bool {
@@ -671,6 +678,17 @@ func prepareVM(c *cli.Context, tx *transaction.Transaction) error {
 	return nil
 }
 
+func getHashFlag(c *cli.Context) (util.Uint160, error) {
+	if !c.IsSet(hashFlagFullName) {
+		return util.Uint160{}, nil
+	}
+	h, err := flags.ParseAddress(c.String(hashFlagFullName))
+	if err != nil {
+		return util.Uint160{}, fmt.Errorf("failed to parse contract hash: %w", err)
+	}
+	return h, nil
+}
+
 func handleLoadNEF(c *cli.Context) error {
 	args := c.Args()
 	if len(args) < 1 {
@@ -725,9 +743,19 @@ func handleLoadNEF(c *cli.Context) error {
 	if err != nil {
 		return err
 	}
+	h, err := getHashFlag(c)
+	if err != nil {
+		return err
+	}
+	cs := &state.ContractBase{
+		Hash:     h,
+		NEF:      nef,
+		Manifest: *m,
+	}
+	setContractStateInContext(c.App, cs)
+
 	v := getVMFromContext(c.App)
 	fmt.Fprintf(c.App.Writer, "READY: loaded %d instructions\n", v.Context().LenInstr())
-	setManifestInContext(c.App, m)
 	changePrompt(c.App)
 	return nil
 }
@@ -811,7 +839,7 @@ func handleLoadGo(c *cli.Context) error {
 	}
 
 	name := strings.TrimSuffix(args[0], ".go")
-	b, di, err := compiler.CompileWithOptions(args[0], nil, &compiler.Options{Name: name})
+	ne, di, err := compiler.CompileWithOptions(args[0], nil, &compiler.Options{Name: name})
 	if err != nil {
 		return fmt.Errorf("failed to compile: %w", err)
 	}
@@ -835,12 +863,22 @@ func handleLoadGo(c *cli.Context) error {
 		}
 	}
 
-	err = prepareVM(c, createFakeTransaction(b.Script, signers))
+	err = prepareVM(c, createFakeTransaction(ne.Script, signers))
 	if err != nil {
 		return err
 	}
+	h, err := getHashFlag(c)
+	if err != nil {
+		return err
+	}
+	cs := &state.ContractBase{
+		Hash:     h,
+		NEF:      *ne,
+		Manifest: *m,
+	}
+	setContractStateInContext(c.App, cs)
+
 	v := getVMFromContext(c.App)
-	setManifestInContext(c.App, m)
 	fmt.Fprintf(c.App.Writer, "READY: loaded %d instructions\n", v.Context().LenInstr())
 	changePrompt(c.App)
 	return nil
@@ -937,7 +975,7 @@ func handleLoadDeployed(c *cli.Context) error {
 	ic.VM.GasLimit = gasLimit
 	ic.VM.LoadScriptWithHash(cs.NEF.Script, cs.Hash, callflag.All)
 	fmt.Fprintf(c.App.Writer, "READY: loaded %d instructions\n", ic.VM.Context().LenInstr())
-	setManifestInContext(c.App, &cs.Manifest)
+	setContractStateInContext(c.App, &cs.ContractBase)
 	changePrompt(c.App)
 	return nil
 }
@@ -992,9 +1030,9 @@ func resetInteropContext(app *cli.App, tx *transaction.Transaction, height ...ui
 	return nil
 }
 
-// resetManifest removes manifest from app context.
+// resetContractState removes loaded contract state from app context.
-func resetManifest(app *cli.App) {
+func resetContractState(app *cli.App) {
-	setManifestInContext(app, nil)
+	setContractStateInContext(app, nil)
 }
 
 // resetState resets state of the app (clear interop context and manifest) so that it's ready
@@ -1004,7 +1042,7 @@ func resetState(app *cli.App, tx *transaction.Transaction, height ...uint32) err
 	if err != nil {
 		return err
 	}
-	resetManifest(app)
+	resetContractState(app)
 	return nil
 }
 
@@ -1023,7 +1061,7 @@ func getManifestFromFile(name string) (*manifest.Manifest, error) {
 
 func handleRun(c *cli.Context) error {
 	v := getVMFromContext(c.App)
-	m := getManifestFromContext(c.App)
+	cs := getContractStateFromContext(c.App)
 	args := c.Args()
 	if len(args) != 0 {
 		var (
@@ -1031,6 +1069,7 @@ func handleRun(c *cli.Context) error {
 			offset     int
 			err        error
 			runCurrent = args[0] != "_"
+			hasRet     bool
 		)
 
 		_, scParams, err := cmdargs.ParseParams(args[1:], true)
@@ -1045,27 +1084,35 @@ func handleRun(c *cli.Context) error {
 			}
 		}
 		if runCurrent {
-			if m == nil {
+			if cs == nil {
-				return fmt.Errorf("manifest is not loaded; either use 'run' command to run loaded script from the start or use 'loadgo' and 'loadnef' commands to provide manifest")
+				return fmt.Errorf("manifest is not loaded; either use 'run' command to run loaded script from the start or use 'loadgo', 'loadnef' or 'loaddeployed' commands to provide manifest")
 			}
-			md := m.ABI.GetMethod(args[0], len(params))
+			md := cs.Manifest.ABI.GetMethod(args[0], len(params))
 			if md == nil {
 				return fmt.Errorf("%w: method not found", ErrInvalidParameter)
 			}
+			hasRet = md.ReturnType != smartcontract.VoidType
 			offset = md.Offset
+			var initOff = -1
+			if initMD := cs.Manifest.ABI.GetMethod(manifest.MethodInit, 0); initMD != nil {
+				initOff = initMD.Offset
+			}
+
+			// Clear context loaded by 'loadgo', 'loadnef' or 'loaddeployed' to properly handle LoadNEFMethod.
+			// At the same time, preserve previously set gas limit and the set of breakpoints.
+			ic := getInteropContextFromContext(c.App)
+			gasLimit := v.GasLimit
+			breaks := v.Context().BreakPoints() // We ensure that there's a context loaded.
+			ic.ReuseVM(v)
+			v.GasLimit = gasLimit
+			v.LoadNEFMethod(&cs.NEF, util.Uint160{}, cs.Hash, callflag.All, hasRet, offset, initOff, nil)
+			for _, bp := range breaks {
+				v.AddBreakPoint(bp)
+			}
 		}
 		for i := len(params) - 1; i >= 0; i-- {
 			v.Estack().PushVal(params[i])
 		}
-		if runCurrent {
-			if !v.Ready() {
-				return errors.New("no program loaded")
-			}
-			v.Context().Jump(offset)
-			if initMD := m.ABI.GetMethod(manifest.MethodInit, 0); initMD != nil {
-				v.Call(initMD.Offset)
-			}
-		}
 	}
 	runVMWithHandling(c)
 	changePrompt(c.App)

cli/vm/cli_test.go

@@ -281,6 +281,97 @@ func (e *executor) checkSlot(t *testing.T, items ...any) {
 	require.NoError(t, err)
 }
 
+func TestRun_WithNewVMContextAndBreakpoints(t *testing.T) {
+	t.Run("contract without init", func(t *testing.T) {
+		src := `package kek
+		func Main(a, b int) int {
+			var c = a + b
+			return c + 5
+		}`
+		tmpDir := t.TempDir()
+		filename := prepareLoadgoSrc(t, tmpDir, src)
+
+		e := newTestVMCLI(t)
+		e.runProgWithTimeout(t, 10*time.Second,
+			"loadgo "+filename,
+			"break 8",
+			"run main 3 5",
+			"run",
+		)
+
+		e.checkNextLine(t, "READY: loaded \\d* instructions")
+		e.checkNextLine(t, "breakpoint added at instruction 8")
+		e.checkNextLine(t, "at breakpoint 8 (PUSH5)*")
+		e.checkStack(t, 13)
+	})
+	t.Run("contract with init", func(t *testing.T) {
+		src := `package kek
+		var I = 5
+		func Main(a, b int) int {
+			var c = a + b
+			return c + I
+		}`
+
+		tmpDir := t.TempDir()
+		filename := prepareLoadgoSrc(t, tmpDir, src)
+
+		e := newTestVMCLI(t)
+		e.runProgWithTimeout(t, 10*time.Second,
+			"loadgo "+filename,
+			"break 10",
+			"run main 3 5",
+			"run",
+		)
+
+		e.checkNextLine(t, "READY: loaded \\d* instructions")
+		e.checkNextLine(t, "breakpoint added at instruction 10")
+		e.checkNextLine(t, "at breakpoint 10 (ADD)*")
+		e.checkStack(t, 13)
+	})
+}
+
+// prepareLoadgoSrc prepares provided SC source file for loading into VM via `loadgo` command.
+func prepareLoadgoSrc(t *testing.T, tmpDir, src string) string {
+	filename := filepath.Join(tmpDir, "vmtestcontract.go")
+	require.NoError(t, os.WriteFile(filename, []byte(src), os.ModePerm))
+	filename = "'" + filename + "'"
+	wd, err := os.Getwd()
+	require.NoError(t, err)
+	goMod := []byte(`module test.example/kek
+require (
+	github.com/nspcc-dev/neo-go/pkg/interop v0.0.0
+)
+replace github.com/nspcc-dev/neo-go/pkg/interop => ` + filepath.Join(wd, "../../pkg/interop") + `
+go 1.18`)
+	require.NoError(t, os.WriteFile(filepath.Join(tmpDir, "go.mod"), goMod, os.ModePerm))
+	return filename
+}
+
+// prepareLoadnefSrc compiles provided SC source and prepares NEF and manifest for loading into VM
+// via `loadnef` command. It returns the name of manifest and NEF files ready to be used in CLI
+// commands.
+func prepareLoadnefSrc(t *testing.T, tmpDir, src string) (string, string) {
+	config.Version = "0.92.0-test"
+
+	nefFile, di, err := compiler.CompileWithOptions("test.go", strings.NewReader(src), nil)
+	require.NoError(t, err)
+	filename := filepath.Join(tmpDir, "vmtestcontract.nef")
+	rawNef, err := nefFile.Bytes()
+	require.NoError(t, err)
+	require.NoError(t, os.WriteFile(filename, rawNef, os.ModePerm))
+	m, err := di.ConvertToManifest(&compiler.Options{})
+	require.NoError(t, err)
+	manifestFile := filepath.Join(tmpDir, "vmtestcontract.manifest.json")
+	rawManifest, err := json.Marshal(m)
+	require.NoError(t, err)
+	require.NoError(t, os.WriteFile(manifestFile, rawManifest, os.ModePerm))
+
+	manifestFile = "'" + manifestFile + "'"
+	filename = "'" + filename + "'"
+
+	return manifestFile, filename
+}
+
 func TestLoad(t *testing.T) {
 	script := []byte{byte(opcode.PUSH3), byte(opcode.PUSH4), byte(opcode.ADD)}
 
@@ -378,19 +469,13 @@ func TestLoad(t *testing.T) {
 			return a * b
 		}
 	}`
+
+	t.Run("loadgo", func(t *testing.T) {
 		tmpDir := t.TempDir()
 
-	checkLoadgo := func(t *testing.T, tName, cName, cErrName string) {
+		checkLoadgo := func(t *testing.T, cName, cErrName string) {
-		t.Run("loadgo "+tName, func(t *testing.T) {
+			filename := prepareLoadgoSrc(t, tmpDir, src)
-			filename := filepath.Join(tmpDir, cName)
-			require.NoError(t, os.WriteFile(filename, []byte(src), os.ModePerm))
-			filename = "'" + filename + "'"
 			filenameErr := filepath.Join(tmpDir, cErrName)
-			require.NoError(t, os.WriteFile(filenameErr, []byte(src+"invalid_token"), os.ModePerm))
-			filenameErr = "'" + filenameErr + "'"
-			goMod := []byte(`module test.example/vmcli
-go 1.18`)
-			require.NoError(t, os.WriteFile(filepath.Join(tmpDir, "go.mod"), goMod, os.ModePerm))
 
 			e := newTestVMCLI(t)
 			e.runProgWithTimeout(t, 10*time.Second,
@@ -403,28 +488,16 @@ go 1.18`)
 			e.checkNextLine(t, "Error:")
 			e.checkNextLine(t, "READY: loaded \\d* instructions")
 			e.checkStack(t, 8)
+		}
+
+		t.Run("simple", func(t *testing.T) {
+			checkLoadgo(t, "vmtestcontract.go", "vmtestcontract_err.go")
+		})
+		t.Run("utf-8 with spaces", func(t *testing.T) {
+			checkLoadgo(t, "тестовый контракт.go", "тестовый контракт с ошибкой.go")
 		})
-	}
 
-	checkLoadgo(t, "simple", "vmtestcontract.go", "vmtestcontract_err.go")
+		t.Run("check calling flags", func(t *testing.T) {
-	checkLoadgo(t, "utf-8 with spaces", "тестовый контракт.go", "тестовый контракт с ошибкой.go")
-
-	prepareLoadgoSrc := func(t *testing.T, srcAllowNotify string) string {
-		filename := filepath.Join(tmpDir, "vmtestcontract.go")
-		require.NoError(t, os.WriteFile(filename, []byte(srcAllowNotify), os.ModePerm))
-		filename = "'" + filename + "'"
-		wd, err := os.Getwd()
-		require.NoError(t, err)
-		goMod := []byte(`module test.example/kek
-require (
-	github.com/nspcc-dev/neo-go/pkg/interop v0.0.0
-)
-replace github.com/nspcc-dev/neo-go/pkg/interop => ` + filepath.Join(wd, "../../pkg/interop") + `
-go 1.18`)
-		require.NoError(t, os.WriteFile(filepath.Join(tmpDir, "go.mod"), goMod, os.ModePerm))
-		return filename
-	}
-	t.Run("loadgo, check calling flags", func(t *testing.T) {
 			srcAllowNotify := `package kek
 		import "github.com/nspcc-dev/neo-go/pkg/interop/runtime"
 		func Main() int {
@@ -432,7 +505,7 @@ go 1.18`)
 			return 1
 		}
 `
-		filename := prepareLoadgoSrc(t, srcAllowNotify)
+			filename := prepareLoadgoSrc(t, tmpDir, srcAllowNotify)
 
 			e := newTestVMCLI(t)
 			e.runProg(t,
@@ -441,7 +514,7 @@ go 1.18`)
 			e.checkNextLine(t, "READY: loaded \\d* instructions")
 			e.checkStack(t, 1)
 		})
-	t.Run("loadgo, check signers", func(t *testing.T) {
+		t.Run("check signers", func(t *testing.T) {
 			srcCheckWitness := `package kek
 		import (
 			"github.com/nspcc-dev/neo-go/pkg/interop/runtime"
@@ -452,7 +525,7 @@ go 1.18`)
 			return runtime.CheckWitness(owner)
 		}
 `
-		filename := prepareLoadgoSrc(t, srcCheckWitness)
+			filename := prepareLoadgoSrc(t, tmpDir, srcCheckWitness)
 			t.Run("invalid", func(t *testing.T) {
 				e := newTestVMCLI(t)
 				e.runProg(t,
@@ -497,45 +570,33 @@ go 1.18`)
 				e.checkStack(t, false)
 			})
 		})
+	})
+
 	t.Run("loadnef", func(t *testing.T) {
-		config.Version = "0.92.0-test"
+		tmpDir := t.TempDir()
 
-		nefFile, di, err := compiler.CompileWithOptions("test.go", strings.NewReader(src), nil)
+		manifestFile, nefFile := prepareLoadnefSrc(t, tmpDir, src)
-		require.NoError(t, err)
-		filename := filepath.Join(tmpDir, "vmtestcontract.nef")
-		rawNef, err := nefFile.Bytes()
-		require.NoError(t, err)
-		require.NoError(t, os.WriteFile(filename, rawNef, os.ModePerm))
-		m, err := di.ConvertToManifest(&compiler.Options{})
-		require.NoError(t, err)
-		manifestFile := filepath.Join(tmpDir, "vmtestcontract.manifest.json")
-		rawManifest, err := json.Marshal(m)
-		require.NoError(t, err)
-		require.NoError(t, os.WriteFile(manifestFile, rawManifest, os.ModePerm))
 		filenameErr := filepath.Join(tmpDir, "vmtestcontract_err.nef")
-		require.NoError(t, os.WriteFile(filenameErr, append([]byte{1, 2, 3, 4}, rawNef...), os.ModePerm))
+		require.NoError(t, os.WriteFile(filenameErr, []byte{1, 2, 3, 4}, os.ModePerm))
 		notExists := filepath.Join(tmpDir, "notexists.json")
-
-		manifestFile = "'" + manifestFile + "'"
-		filename = "'" + filename + "'"
 		filenameErr = "'" + filenameErr + "'"
 
 		e := newTestVMCLI(t)
 		e.runProg(t,
 			"loadnef",
 			"loadnef "+filenameErr+" "+manifestFile,
-			"loadnef "+filename+" "+notExists,
+			"loadnef "+nefFile+" "+notExists,
-			"loadnef "+filename+" "+filename,
+			"loadnef "+nefFile+" "+nefFile,
-			"loadnef "+filename+" "+manifestFile,
+			"loadnef "+nefFile+" "+manifestFile,
 			"run main add 3 5",
-			"loadnef "+filename,
+			"loadnef "+nefFile,
 			"run main add 3 5",
-			"loadnef "+filename+" "+cmdargs.CosignersSeparator,
+			"loadnef "+nefFile+" "+cmdargs.CosignersSeparator,
-			"loadnef "+filename+" "+manifestFile+" "+cmdargs.CosignersSeparator,
+			"loadnef "+nefFile+" "+manifestFile+" "+cmdargs.CosignersSeparator,
-			"loadnef "+filename+" "+manifestFile+" "+"not-a-separator",
+			"loadnef "+nefFile+" "+manifestFile+" "+"not-a-separator",
-			"loadnef "+filename+" "+cmdargs.CosignersSeparator+" "+util.Uint160{1, 2, 3}.StringLE(),
+			"loadnef "+nefFile+" "+cmdargs.CosignersSeparator+" "+util.Uint160{1, 2, 3}.StringLE(),
 			"run main add 3 5",
-			"loadnef "+filename+" "+manifestFile+" "+cmdargs.CosignersSeparator+" "+util.Uint160{1, 2, 3}.StringLE(),
+			"loadnef "+nefFile+" "+manifestFile+" "+cmdargs.CosignersSeparator+" "+util.Uint160{1, 2, 3}.StringLE(),
 			"run main add 3 5",
 		)
 
@@ -557,6 +618,72 @@ go 1.18`)
 	})
 }
 
+func TestLoad_RunWithCALLT(t *testing.T) {
+	// Our smart compiler will generate CALLT instruction for the following StdLib call:
+	src := `package kek
+		import "github.com/nspcc-dev/neo-go/pkg/interop/native/std"
+		func Main() int {
+			return std.Atoi("123", 10)
+		}`
+
+	t.Run("loadgo", func(t *testing.T) {
+		tmp := t.TempDir()
+		filename := prepareLoadgoSrc(t, tmp, src)
+		e := newTestVMCLI(t)
+		e.runProg(t,
+			"loadgo "+filename,
+			"run main",
+		)
+		e.checkNextLine(t, "READY: loaded \\d* instructions")
+		e.checkStack(t, 123)
+	})
+
+	t.Run("loadnef", func(t *testing.T) {
+		tmpDir := t.TempDir()
+		manifestFile, nefFile := prepareLoadnefSrc(t, tmpDir, src)
+
+		e := newTestVMCLI(t)
+		e.runProg(t,
+			"loadnef "+nefFile+" "+manifestFile,
+			"run main",
+		)
+		e.checkNextLine(t, "READY: loaded \\d* instructions")
+		e.checkStack(t, 123)
+	})
+
+	t.Run("loaddeployed", func(t *testing.T) {
+		// We'll use `Runtime example` example contract which has a call to native Management
+		// inside performed via CALLT instruction (`destroy` method).
+		e := newTestVMClIWithState(t)
+		var (
+			cH    util.Uint160
+			cName = "Runtime example"
+			bc    = e.cli.chain
+		)
+		for i := int32(1); ; i++ {
+			h, err := bc.GetContractScriptHash(i)
+			if err != nil {
+				break
+			}
+			cs := bc.GetContractState(h)
+			if cs == nil {
+				break
+			}
+			if cs.Manifest.Name == cName {
+				cH = cs.Hash
+				break
+			}
+		}
+		require.NotEmpty(t, cH, fmt.Sprintf("failed to locate `%s` example contract with CALLT usage in the simple chain", cName))
+		e.runProg(t,
+			"loaddeployed "+cH.StringLE()+" -- NbrUYaZgyhSkNoRo9ugRyEMdUZxrhkNaWB:Global", // the contract's owner got from the contract's code.
+			"run destroy",
+		)
+		e.checkNextLine(t, "READY: loaded \\d* instructions")
+		e.checkStack(t) // Nothing on stack, successful execution.
+	})
+}
+
 func TestRunWithDifferentArguments(t *testing.T) {
 	src := `package kek
 	var a = 1

examples/runtime/runtime.go

@@ -65,7 +65,7 @@ func Verify() bool {
 
 // Destroy destroys the contract, only the owner can do that.
 func Destroy() {
-	if !Verify() {
+	if !CheckWitness() {
 		panic("only owner can destroy")
 	}
 	management.Destroy()
@@ -74,7 +74,7 @@ func Destroy() {
 // Update updates the contract, only the owner can do that. _deploy will be called
 // after update.
 func Update(nef, manifest []byte) {
-	if !Verify() {
+	if !CheckWitness() {
 		panic("only owner can update")
 	}
 	management.Update(nef, manifest)

pkg/vm/context.go

@@ -350,3 +350,10 @@ func DynamicOnUnload(v *VM, ctx *Context, commit bool) error {
 	}
 	return nil
 }
+
+// BreakPoints returns the current set of Context's breakpoints.
+func (c *Context) BreakPoints() []int {
+	res := make([]int, len(c.sc.breakPoints))
+	copy(res, c.sc.breakPoints)
+	return res
+}

pkg/vm/debug_test.go

@@ -4,6 +4,8 @@ import (
 	"math/big"
 	"testing"
 
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
+	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
 	"github.com/stretchr/testify/require"
 )
@@ -40,3 +42,20 @@ func TestVM_Debug(t *testing.T) {
 		require.Equal(t, big.NewInt(5), v.estack.Top().Value())
 	})
 }
+
+func TestContext_BreakPoints(t *testing.T) {
+	prog := makeProgram(opcode.CALL, 3, opcode.RET,
+		opcode.PUSH2, opcode.PUSH3, opcode.ADD, opcode.RET)
+	v := load(prog)
+	v.AddBreakPoint(3)
+	v.AddBreakPoint(5)
+	require.Equal(t, []int{3, 5}, v.Context().BreakPoints())
+
+	// Preserve the set of breakpoints on Call.
+	v.Call(3)
+	require.Equal(t, []int{3, 5}, v.Context().BreakPoints())
+
+	// New context -> clean breakpoints.
+	v.loadScriptWithCallingHash(prog, nil, util.Uint160{}, util.Uint160{}, callflag.All, 1, 3, nil)
+	require.Equal(t, []int{}, v.Context().BreakPoints())
+}