decode: Lean in to io.RuneScanner

So that it's easier to compose your own .DecodeJSON methods, since
.DecodeJSON takes an io.RuneScanner.

1 files changed, 3 insertions, 7 deletions

diff --git a/decode_scan.go b/decode_scan.go
index fb8a6ec..eee61fc 100644
--- a/decode_scan.go
+++ b/decode_scan.go
@@ -28,7 +28,7 @@ type runeTypeScanner interface {
 // runeTypeScannerImpl /////////////////////////////////////////////////////////////////////////////
 
 type runeTypeScannerImpl struct {
-	inner io.RuneReader
+	inner io.RuneScanner
 
 	initialized bool
 
@@ -73,9 +73,7 @@ func (sc *runeTypeScannerImpl) ReadRuneType() (rune, int, RuneType, error) {
 	case sc.stuck:
 		// do nothing
 	case sc.repeat:
-		if _, ok := sc.inner.(io.RuneScanner); ok {
-			_, _, _ = sc.inner.ReadRune()
-		}
+		_, _, _ = sc.inner.ReadRune()
 	default:
 		var err error
 		sc.rRune, sc.rSize, err = sc.inner.ReadRune()
@@ -138,9 +136,7 @@ func (sc *runeTypeScannerImpl) UnreadRune() error {
 		return ErrInvalidUnreadRune
 	}
 	sc.repeat = true
-	if rs, ok := sc.inner.(io.RuneScanner); ok {
-		_ = rs.UnreadRune()
-	}
+	_ = sc.inner.UnreadRune()
 	return nil
 }