WIP

FerretDB · AlekSi · Aug 29, 2023 · Aug 28, 2023 · Aug 28, 2023 · Aug 28, 2023
commit 426b969950599347d20c0f794b80f77a8bcdc15d
@@ -64,18 +64,19 @@ func NewCommandErrorMsgWithArgument(code ErrorCode, msg string, argument string)
 	}
 }
 
-// Error implements error interface.
-func (e *CommandError) Error() string {
-	return fmt.Sprintf("%[1]s (%[1]d): %[2]v", e.code, e.err)
-}
-
 // Err returns original error.
 //
 // It is not called Unwrap to prevent unwrapping by errors.Is and errors.As.
+// CommandError should not be unwrappable.
 func (e *CommandError) Err() error {
 	return e.err
 }
 
+// Error implements error interface.
+func (e *CommandError) Error() string {
+	return fmt.Sprintf("%[1]s (%[1]d): %[2]v", e.code, e.err)
+}
+
 // Code implements ProtoErr interface.
 func (e *CommandError) Code() ErrorCode {
 	return e.code

@@ -14,8 +14,14 @@
 
 package commonerrors
 
-import "testing"
+import (
+	"io"
+	"testing"
 
-func TestDummy(t *testing.T) {
-	// we need at least one test per package to correctly calculate coverage
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNoWrapping(t *testing.T) {
+	err := NewCommandError(errInternalError, io.EOF)
+	assert.NotErrorIs(t, err, io.EOF)
 }
@@ -322,10 +322,13 @@ type ErrInfo struct {
 type ProtoErr interface {
 	// Error returns error representation for logging and debugging.
 	error
+
 	// Code returns error's code.
 	Code() ErrorCode
-	// Document returns a document representation of the error.
+
+	// Document returns error representation for returning to the client.
 	Document() *types.Document
+
 	// Info returns additional error information, or nil.
 	Info() *ErrInfo
 }

@@ -21,6 +21,15 @@ import (
 	"github.com/FerretDB/FerretDB/internal/util/must"
 )
 
+// writeError represents protocol write error.
+// It required to build the correct write error result.
+// The index field is optional and won't be used if it's nil.
+type writeError struct {
+	index  int32
+	errmsg string
+	code   ErrorCode
+}
+
 // WriteErrors represents a slice of protocol write errors.
 // It could be returned for Update, Insert, Delete, and Replace operations.
 type WriteErrors struct {
@@ -68,9 +77,7 @@ func (we *WriteErrors) Document() *types.Document {
 	for _, e := range we.errs {
 		doc := must.NotFail(types.NewDocument())
 
-		if e.index != nil {
-			doc.Set("index", *e.index)
-		}
+		doc.Set("index", e.index)
 
 		// Fields "code" and "errmsg" must always be filled in so that clients can parse the error message.
 		// Otherwise, the mongo client would parse it as a CommandError.
@@ -101,21 +108,21 @@ func (we *WriteErrors) Append(err error, index int32) {
 
 	switch {
 	case errors.As(err, &writeErr):
-		writeErr.index = &index
+		writeErr.index = index
 		we.errs = append(we.errs, *writeErr)
 
 	case errors.As(err, &cmdErr):
 		we.errs = append(we.errs, writeError{
 			code:   cmdErr.code,
 			errmsg: cmdErr.err.Error(),
-			index:  &index,
+			index:  index,
 		})
 
 	default:
 		we.errs = append(we.errs, writeError{
 			code:   errInternalError,
 			errmsg: err.Error(),
-			index:  &index,
+			index:  index,
 		})
 	}
 }
@@ -128,7 +135,7 @@ func (we *WriteErrors) Len() int {
 // Merge merges the given WriteErrors with the current one and sets the given index.
 func (we *WriteErrors) Merge(we2 *WriteErrors, index int32) {
 	for _, e := range we2.errs {
-		e.index = &index
+		e.index = index
 		we.errs = append(we.errs, e)
 	}
 }