internal/trace/v2: make readBatch param more permissive

This function is copied to x/exp/trace. In https://go.dev/cl/566255 a
change is made where the source is a bytes.Reader instead of a
bufio.Reader from one of the two callers. Change the prototype here
instead of diverging the implementations.

Change-Id: I594224663996eadbc8c388442d68ac5706c52c8e
Reviewed-on: https://go-review.googlesource.com/c/go/+/566236
Auto-Submit: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

diff --git a/src/internal/trace/v2/batch.go b/src/internal/trace/v2/batch.go
index 899eb0f59bcf800bc92e629abadda9b2a68bbdc6..d7afc06eecd158bb41e9cbdf83fbb7c51cc18078 100644 (file)
--- a/src/internal/trace/v2/batch.go
+++ b/src/internal/trace/v2/batch.go
@@ -5,7 +5,6 @@
 package trace
 
 import (
-       "bufio"
        "bytes"
        "encoding/binary"
        "fmt"
@@ -43,7 +42,10 @@ func (b *batch) isFreqBatch() bool {
 }
 
 // readBatch reads the next full batch from r.
-func readBatch(r *bufio.Reader) (batch, uint64, error) {
+func readBatch(r interface {
+       io.Reader
+       io.ByteReader
+}) (batch, uint64, error) {
        // Read batch header byte.
        b, err := r.ReadByte()
        if err != nil {