update dependencies (#296)

vendor/codeberg.org/gruf/go-errors/errors.go

@@ -0,0 +1,180 @@
+package errors
+
+import "fmt"
+
+// ErrorContext defines a wrappable error with the ability to hold extra contextual information
+type ErrorContext interface {
+	// implement base error interface
+	error
+
+	// Is identifies whether the receiver contains / is the target
+	Is(error) bool
+
+	// Unwrap reveals the underlying wrapped error (if any!)
+	Unwrap() error
+
+	// Value attempts to fetch contextual data for given key from this ErrorContext
+	Value(string) (interface{}, bool)
+
+	// Append allows adding contextual data to this ErrorContext
+	Append(...KV) ErrorContext
+
+	// Data returns the contextual data structure associated with this ErrorContext
+	Data() ErrorData
+}
+
+// New returns a new ErrorContext created from string
+func New(msg string) ErrorContext {
+	return stringError(msg)
+}
+
+// Newf returns a new ErrorContext created from format string
+func Newf(s string, a ...interface{}) ErrorContext {
+	return stringError(fmt.Sprintf(s, a...))
+}
+
+// Wrap ensures supplied error is an ErrorContext, wrapping if necessary
+func Wrap(err error) ErrorContext {
+	// Nil error, do nothing
+	if err == nil {
+		return nil
+	}
+
+	// Check if this is already wrapped somewhere in stack
+	if xerr, ok := err.(*errorContext); ok {
+		return xerr
+	} else if As(err, &xerr) {
+		// This is really not an ideal situation,
+		// but we try to make do by salvaging the
+		// contextual error data from earlier in
+		// stack, setting current error to the top
+		// and setting the unwrapped error to inner
+		return &errorContext{
+			data: xerr.data,
+			innr: Unwrap(err),
+			err:  err,
+		}
+	}
+
+	// Return new Error type
+	return &errorContext{
+		data: NewData(),
+		innr: nil,
+		err:  err,
+	}
+}
+
+// WrapMsg wraps supplied error as inner, returning an ErrorContext
+// with a new outer error made from the supplied message string
+func WrapMsg(err error, msg string) ErrorContext {
+	// Nil error, do nothing
+	if err == nil {
+		return nil
+	}
+
+	// Check if this is already wrapped
+	var xerr *errorContext
+	if As(err, &xerr) {
+		return &errorContext{
+			data: xerr.data,
+			innr: err,
+			err:  New(msg),
+		}
+	}
+
+	// Return new wrapped error
+	return &errorContext{
+		data: NewData(),
+		innr: err,
+		err:  stringError(msg),
+	}
+}
+
+// WrapMsgf wraps supplied error as inner, returning an ErrorContext with
+// a new outer error made from the supplied message format string
+func WrapMsgf(err error, msg string, a ...interface{}) ErrorContext {
+	return WrapMsg(err, fmt.Sprintf(msg, a...))
+}
+
+// ErrorData attempts fetch ErrorData from supplied error, returns nil otherwise
+func Data(err error) ErrorData {
+	x, ok := err.(ErrorContext)
+	if ok {
+		return x.Data()
+	}
+	return nil
+}
+
+// stringError is the simplest ErrorContext implementation
+type stringError string
+
+func (e stringError) Error() string {
+	return string(e)
+}
+
+func (e stringError) Is(err error) bool {
+	se, ok := err.(stringError)
+	return ok && e == se
+}
+
+func (e stringError) Unwrap() error {
+	return nil
+}
+
+func (e stringError) Value(key string) (interface{}, bool) {
+	return nil, false
+}
+
+func (e stringError) Append(kvs ...KV) ErrorContext {
+	data := NewData()
+	data.Append(kvs...)
+	return &errorContext{
+		data: data,
+		innr: nil,
+		err:  e,
+	}
+}
+
+func (e stringError) Data() ErrorData {
+	return nil
+}
+
+// errorContext is the *actual* ErrorContext implementation
+type errorContext struct {
+	// data contains any appended context data, there will only ever be one
+	// instance of data within an ErrorContext stack
+	data ErrorData
+
+	// innr is the inner wrapped error in this structure, it is only accessible
+	// via .Unwrap() or via .Is()
+	innr error
+
+	// err is the top-level error in this wrapping structure, we identify
+	// as this error type via .Is() and return its error message
+	err error
+}
+
+func (e *errorContext) Error() string {
+	return e.err.Error()
+}
+
+func (e *errorContext) Is(err error) bool {
+	return Is(e.err, err) || Is(e.innr, err)
+}
+
+func (e *errorContext) Unwrap() error {
+	return e.innr
+}
+
+func (e *errorContext) Value(key string) (interface{}, bool) {
+	return e.data.Value(key)
+}
+
+func (e *errorContext) Append(kvs ...KV) ErrorContext {
+	e.data.Append(kvs...)
+	return e
+}
+
+func (e *errorContext) Data() ErrorData {
+	return e.data
+}