revert changes to consumer group invalid return values

brzyangg · Oct 25, 2018 · 48324a3 · 48324a3
1 parent 3306e5a
commit 48324a3
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Showing 2 changed files with 8 additions and 7 deletions.
diff --git a/reader.go b/reader.go
@@ -1368,10 +1368,11 @@ func (r *Reader) ReadLag(ctx context.Context) (lag int64, err error) {
 	return
 }
 
-// Offset returns the current offset of the reader.
+// Offset returns the current absolute offset of the reader, or -1
+// if r is backed by a consumer group
 func (r *Reader) Offset() int64 {
 	if r.useConsumerGroup() {
-		return 0
+		return -1
 	}
 
 	r.mutex.Lock()
@@ -1386,7 +1387,7 @@ func (r *Reader) Offset() int64 {
 // Lag returns the lag of the last message returned by ReadMessage.
 func (r *Reader) Lag() int64 {
 	if r.useConsumerGroup() {
-		return 0
+		return -1
 	}
 
 	r.mutex.Lock()

diff --git a/reader_test.go b/reader_test.go
@@ -550,15 +550,15 @@ func TestReaderSetOffsetWhenConsumerGroupsEnabled(t *testing.T) {
 
 func TestReaderOffsetWhenConsumerGroupsEnabled(t *testing.T) {
 	r := &Reader{config: ReaderConfig{GroupID: "not-zero"}}
-	if offset := r.Offset(); offset != 0 {
-		t.Fatalf("expected 0; got %v", offset)
+	if offset := r.Offset(); offset != -1 {
+		t.Fatalf("expected -1; got %v", offset)
 	}
 }
 
 func TestReaderLagWhenConsumerGroupsEnabled(t *testing.T) {
 	r := &Reader{config: ReaderConfig{GroupID: "not-zero"}}
-	if offset := r.Lag(); offset != 0 {
-		t.Fatalf("expected 0; got %v", offset)
+	if offset := r.Lag(); offset != -1 {
+		t.Fatalf("expected -1; got %v", offset)
 	}
 }