diff --git a/unvis.go b/unvis.go
index f8dd6b1..8a26218 100644
--- a/unvis.go
+++ b/unvis.go
@@ -74,7 +74,7 @@ func newParser(input string, flag VisFlag) *unvisParser {
 func unvisPlainRune(p *unvisParser) ([]byte, error) {
 	ch, err := p.Peek()
 	if err != nil {
-		return nil, fmt.Errorf("plain rune: %s", ch)
+		return nil, fmt.Errorf("plain rune: %c", ch)
 	}
 	p.Next()
 
@@ -238,8 +238,6 @@ func unvisEscapeSequence(p *unvisParser) ([]byte, error) {
 	default:
 		return unvisEscapeCStyle(p)
 	}
-
-	return nil, fmt.Errorf("escape sequence: unsupported sequence: %q", ch)
 }
 
 func unvisRune(p *unvisParser) ([]byte, error) {
diff --git a/vis_test.go b/vis_test.go
index e4ef083..5177a58 100644
--- a/vis_test.go
+++ b/vis_test.go
@@ -121,7 +121,7 @@ func TestVisChanged(t *testing.T) {
 			t.Errorf("unexpected error with %q: %s", test, err)
 		}
 		if enc == test {
-			t.Errorf("expected encoding of %q to be changed")
+			t.Errorf("expected encoding of %q to be changed", test)
 		}
 	}
 }