Initial commit

errors/errors.go

@@ -0,0 +1,114 @@
+package errors
+
+import (
+	"errors"
+	"fmt"
+	"runtime"
+	"strings"
+)
+
+type fatal interface {
+	Fatal() bool
+}
+
+func IsFatal(err error) bool {
+	te, ok := errors.Unwrap(err).(fatal)
+	return ok && te.Fatal()
+}
+
+func As(err error, target any) bool {
+	return errors.As(err, target)
+}
+
+func Is(err, target error) bool {
+	return errors.Is(err, target)
+}
+
+func Unwrap(err error) error {
+	return errors.Unwrap(err)
+}
+
+type Error struct {
+	Err   error
+	Stack string
+	fatal bool
+}
+
+func (e *Error) Error() string {
+	var sb strings.Builder
+	sb.WriteString(fmt.Sprintf("%v\n", e.Err))
+	return sb.String()
+}
+
+func (e *Error) ErrorWithStack() string {
+	var sb strings.Builder
+	sb.WriteString(fmt.Sprintf("%v\n", e.Err))
+	sb.WriteString(fmt.Sprintf("Stack Trace:\n%s", e.Stack))
+	return sb.String()
+}
+
+func (e *Error) Fatal() bool {
+	return e.fatal
+}
+
+func (e *Error) Unwrap() error {
+	return e.Err
+}
+
+func NewError(err error) error {
+	if err == nil {
+		return nil
+	}
+
+	// Check if it's already of our own
+	// Error type, so we don't add stack twice.
+	var asError *Error
+	if errors.As(err, &asError) {
+		return err
+	}
+
+	// Get the stack trace
+	var stack strings.Builder
+	buf := make([]uintptr, 50)
+	n := runtime.Callers(2, buf)
+	frames := runtime.CallersFrames(buf[:n])
+
+	// Format the stack trace
+	for {
+		frame, more := frames.Next()
+		// Skip runtime and standard library frames
+		if !strings.Contains(frame.File, "runtime/") {
+			stack.WriteString(fmt.Sprintf("\t%s:%d - %s\n", frame.File, frame.Line, frame.Function))
+		}
+		if !more {
+			break
+		}
+	}
+
+	return &Error{
+		Err:   err,
+		Stack: stack.String(),
+	}
+}
+
+func NewFatalError(err error) error {
+	if err == nil {
+		return nil
+	}
+
+	// Check if it's already of our own
+	// Error type.
+	var asError *Error
+	if errors.As(err, &asError) {
+		return err
+	}
+	err2 := NewError(err)
+	err2.(*Error).fatal = true
+	return err2
+}
+
+var ConnectionError error = fmt.Errorf("connection error")
+
+func NewConnectionError(err error) error {
+	return fmt.Errorf("%w: %w", ConnectionError, err)
+}

errors/errors_test.go

@@ -0,0 +1,71 @@
+package errors
+
+import (
+	"errors"
+	"fmt"
+	"testing"
+)
+
+type CustomError struct {
+	Err error
+}
+
+func (e *CustomError) Error() string { return e.Err.Error() }
+
+func IsCustomError(err error) bool {
+	var asError *CustomError
+	return errors.As(err, &asError)
+}
+
+func TestWrapping(t *testing.T) {
+	t.Parallel()
+	originalErr := errors.New("original error")
+	err1 := NewError(originalErr)
+	if !errors.Is(err1, originalErr) {
+		t.Errorf("original error is not wrapped")
+	}
+	if !Is(err1, originalErr) {
+		t.Errorf("original error is not wrapped")
+	}
+	unwrappedErr := errors.Unwrap(err1)
+	if !errors.Is(unwrappedErr, originalErr) {
+		t.Errorf("original error is not wrapped")
+	}
+	if !Is(unwrappedErr, originalErr) {
+		t.Errorf("original error is not wrapped")
+	}
+	unwrappedErr = Unwrap(err1)
+	if !errors.Is(unwrappedErr, originalErr) {
+		t.Errorf("original error is not wrapped")
+	}
+	if !Is(unwrappedErr, originalErr) {
+		t.Errorf("original error is not wrapped")
+	}
+	wrappedErr := fmt.Errorf("wrapped: %w", originalErr)
+	if !errors.Is(wrappedErr, originalErr) {
+		t.Errorf("original error is not wrapped")
+	}
+	if !Is(wrappedErr, originalErr) {
+		t.Errorf("original error is not wrapped")
+	}
+}
+
+func TestNewError(t *testing.T) {
+	t.Parallel()
+	originalErr := &CustomError{errors.New("err1")}
+	if !IsCustomError(originalErr) {
+		t.Errorf("TestNewError fail #1")
+	}
+	err1 := NewError(originalErr)
+	if !IsCustomError(err1) {
+		t.Errorf("TestNewError fail #2")
+	}
+	wrappedErr1 := fmt.Errorf("wrapped %w", err1)
+	if !IsCustomError(wrappedErr1) {
+		t.Errorf("TestNewError fail #3")
+	}
+	unwrappedErr1 := Unwrap(wrappedErr1)
+	if !IsCustomError(unwrappedErr1) {
+		t.Errorf("TestNewError fail #4")
+	}
+}