Add multi error

.github/workflows/linter.yml

@@ -1,34 +0,0 @@
-name: Linter
-
-on:
-  push:
-    branches:
-      - dev
-    paths:
-      - "**/*.go"
-      - ".github/workflows/linter.yml"
-  pull_request:
-    types: [ opened, synchronize, reopened ]
-    paths:
-      - "**/*.go"
-      - ".github/workflows/linter.yml"
-
-jobs:
-  lint:
-    if: github.repository == 'sagernet/sing'
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v2
-      - name: Get latest go version
-        id: version
-        run: |
-          echo ::set-output name=go_version::$(curl -s https://raw.githubusercontent.com/actions/go-versions/main/versions-manifest.json | grep -oE '"version": "[0-9]{1}.[0-9]{1,}(.[0-9]{1,})?"' | head -1 | cut -d':' -f2 | sed 's/ //g; s/"//g')
-      - name: Setup Go
-        uses: actions/setup-go@v2
-        with:
-          go-version: ${{ steps.version.outputs.go_version }}
-      - name: golangci-lint
-        uses: golangci/golangci-lint-action@v3
-        with:
-          version: latest

common/cond.go

@@ -78,6 +78,20 @@ func Filter[T any](arr []T, block func(it T) bool) []T {
 	return retArr
 }
 
+func FilterNotNil[T any](arr []T) []T {
+	return Filter(arr, func(it T) bool {
+		var anyIt any = it
+		return anyIt != nil
+	})
+}
+
+func FilterNotDefault[T comparable](arr []T) []T {
+	var defaultValue T
+	return Filter(arr, func(it T) bool {
+		return it != defaultValue
+	})
+}
+
 func Find[T any](arr []T, block func(it T) bool) T {
 	for _, it := range arr {
 		if block(it) {
@@ -163,6 +177,7 @@ func Must2(_, _ any, err error) {
 	}
 }
 
+// Deprecated: use E.Errors
 func AnyError(errs ...error) error {
 	for _, err := range errs {
 		if err != nil {

common/exceptions/cause.go

@@ -0,0 +1,17 @@
+package exceptions
+
+type causeError struct {
+	message string
+	cause   error
+}
+
+func (e *causeError) Error() string {
+	if e.cause == nil {
+		return e.message
+	}
+	return e.message + ": " + e.cause.Error()
+}
+
+func (e *causeError) Unwrap() error {
+	return e.cause
+}

common/exceptions/error.go

@@ -8,39 +8,16 @@ import (
 	"net"
 	"os"
 
+	"github.com/sagernet/sing/common"
 	F "github.com/sagernet/sing/common/format"
 )
 
-type causeError struct {
-	message string
-	cause   error
+type Handler interface {
+	NewError(ctx context.Context, err error)
 }
 
-func (e *causeError) Error() string {
-	if e.cause == nil {
-		return e.message
-	}
-	return e.message + ": " + e.cause.Error()
-}
-
-func (e *causeError) Unwrap() error {
-	return e.cause
-}
-
-type extendedError struct {
-	message string
-	cause   error
-}
-
-func (e *extendedError) Error() string {
-	if e.cause == nil {
-		return e.message
-	}
-	return e.cause.Error() + ": " + e.message
-}
-
-func (e *extendedError) Unwrap() error {
-	return e.cause
+type MultiError interface {
+	UnwrapMulti() []error
 }
 
 func New(message ...any) error {
@@ -55,23 +32,17 @@ func Extend(cause error, message ...any) error {
 	return &extendedError{F.ToString(message...), cause}
 }
 
-type HasInnerError interface {
-	Unwrap() error
-}
-
-func Unwrap(err error) error {
-	for {
-		inner, ok := err.(HasInnerError)
-		if !ok {
-			break
-		}
-		innerErr := inner.Unwrap()
-		if innerErr == nil {
-			break
-		}
-		err = innerErr
+func Errors(errors ...error) error {
+	errors = common.FilterNotNil(errors)
+	switch len(errors) {
+	case 0:
+		return nil
+	case 1:
+		return errors[0]
+	}
+	return &multiError{
+		errors: errors,
 	}
-	return err
 }
 
 func IsCanceled(err error) bool {
@@ -81,24 +52,3 @@ func IsCanceled(err error) bool {
 func IsClosed(err error) bool {
 	return errors.Is(err, io.EOF) || errors.Is(err, net.ErrClosed) || errors.Is(err, io.ErrClosedPipe) || errors.Is(err, os.ErrClosed)
 }
-
-type TimeoutError interface {
-	Timeout() bool
-}
-
-func IsTimeout(err error) bool {
-	if unwrapErr := errors.Unwrap(err); unwrapErr != nil {
-		err = unwrapErr
-	}
-	if ne, ok := err.(*os.SyscallError); ok {
-		err = ne.Err
-	}
-	if timeoutErr, isTimeoutErr := err.(TimeoutError); isTimeoutErr {
-		return timeoutErr.Timeout()
-	}
-	return false
-}
-
-type Handler interface {
-	NewError(ctx context.Context, err error)
-}

common/exceptions/extend.go

@@ -0,0 +1,17 @@
+package exceptions
+
+type extendedError struct {
+	message string
+	cause   error
+}
+
+func (e *extendedError) Error() string {
+	if e.cause == nil {
+		return e.message
+	}
+	return e.cause.Error() + ": " + e.message
+}
+
+func (e *extendedError) Unwrap() error {
+	return e.cause
+}

common/exceptions/inner.go

@@ -0,0 +1,20 @@
+package exceptions
+
+type HasInnerError interface {
+	Unwrap() error
+}
+
+func Unwrap(err error) error {
+	for {
+		inner, ok := err.(HasInnerError)
+		if !ok {
+			break
+		}
+		innerErr := inner.Unwrap()
+		if innerErr == nil {
+			break
+		}
+		err = innerErr
+	}
+	return err
+}

common/exceptions/multi.go

@@ -0,0 +1,31 @@
+package exceptions
+
+import (
+	"errors"
+	"strings"
+
+	"github.com/sagernet/sing/common"
+	F "github.com/sagernet/sing/common/format"
+)
+
+type multiError struct {
+	errors []error
+}
+
+func (e *multiError) Error() string {
+	return "multi error: (" + strings.Join(common.Map(e.errors, F.ToString0[error]), " | ") + ")"
+}
+
+func (e *multiError) Unwrap() error {
+	return e.errors[0]
+}
+
+func (e *multiError) UnwrapMulti() []error {
+	return e.errors
+}
+
+func (e *multiError) Is(err error) bool {
+	return common.Any(e.errors, func(it error) bool {
+		return errors.Is(it, err)
+	})
+}

common/exceptions/timeout.go

@@ -0,0 +1,23 @@
+package exceptions
+
+import (
+	"errors"
+	"os"
+)
+
+type TimeoutError interface {
+	Timeout() bool
+}
+
+func IsTimeout(err error) bool {
+	if unwrapErr := errors.Unwrap(err); unwrapErr != nil {
+		err = unwrapErr
+	}
+	if ne, ok := err.(*os.SyscallError); ok {
+		err = ne.Err
+	}
+	if timeoutErr, isTimeoutErr := err.(TimeoutError); isTimeoutErr {
+		return timeoutErr.Timeout()
+	}
+	return false
+}

protocol/http/handshake.go

@@ -118,7 +118,7 @@ func HandleConnection(ctx context.Context, conn net.Conn, reader *std_bufio.Read
 
 		response, err := httpClient.Do(request)
 		if err != nil {
-			return common.AnyError(innerErr, err, responseWith(request, http.StatusBadGateway).Write(conn))
+			return E.Errors(innerErr, err, responseWith(request, http.StatusBadGateway).Write(conn))
 		}
 
 		removeHopByHopHeaders(response.Header)
@@ -133,7 +133,7 @@ func HandleConnection(ctx context.Context, conn net.Conn, reader *std_bufio.Read
 
 		err = response.Write(conn)
 		if err != nil {
-			return common.AnyError(innerErr, err)
+			return E.Errors(innerErr, err)
 		}
 
 		if !keepAlive {

protocol/socks/handshake.go

@@ -224,7 +224,7 @@ func HandleConnection0(ctx context.Context, conn net.Conn, version byte, authent
 				close(done)
 			}()
 			err = common.Error(io.Copy(io.Discard, conn))
-			return common.AnyError(innerError, err)
+			return E.New(innerError, err)
 		default:
 			err = socks5.WriteResponse(conn, socks5.Response{
 				ReplyCode: socks5.ReplyCodeUnsupported,