go-delve/delve · error

'substitutePath' requires both 'from' and 'to' entries

Error message

'substitutePath' requires both 'from' and 'to' entries

What it means

Error "'substitutePath' requires both 'from' and 'to' entries" thrown in go-delve/delve.

Source

Thrown at service/dap/types.go:260

	To string `json:"to,omitempty"`
}

func (m *SubstitutePath) UnmarshalJSON(data []byte) error {
	// use custom unmarshal to check if both from/to are set.
	type tmpType struct {
		From *string
		To   *string
	}
	var tmp tmpType

	if err := json.Unmarshal(data, &tmp); err != nil {
		if _, ok := err.(*json.UnmarshalTypeError); ok {
			return fmt.Errorf(`cannot use %s as 'substitutePath' of type {"from":string, "to":string}`, data)
		}
		return err
	}
	if tmp.From == nil || tmp.To == nil {
		return errors.New("'substitutePath' requires both 'from' and 'to' entries")
	}
	*m = SubstitutePath{*tmp.From, *tmp.To}
	return nil
}

// AttachConfig is the collection of attach request attributes recognized by DAP implementation.
// 'processId' and 'waitFor' are mutually exclusive, and can't be specified at the same time.
type AttachConfig struct {
	// Acceptable values are:
	//   "local": attaches to the local process with the given ProcessID.
	//   "remote": expects the debugger to already be running to "attach" to an in-progress debug session.
	//
	// Default is "local".
	Mode string `json:"mode"`

	// The numeric ID of the process to be debugged.
	ProcessID int `json:"processId,omitempty"`

View on GitHub (pinned to a23773e6c3)

When it happens

Trigger: Thrown at service/dap/types.go:260 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of go-delve/delve@a23773e6c3 (2026-08-31). Data as JSON: /api/errors/7601a502b2042923. Report an issue: GitHub.