fix: display extra data as text instead of hex in test output (#387)

Author: fkondej

playground/test_tx.go

@@ -241,14 +241,12 @@ func SendTestTransaction(ctx context.Context, cfg *TestTxConfig) error {
 				// Get block to show extra data (builder name)
 				block, err := elClient.BlockByNumber(ctx, receipt.BlockNumber)
 				if err == nil && block != nil {
-					extraHex := hex.EncodeToString(block.Extra())
-					fmt.Printf("  Extra Data: 0x%s\n", extraHex)
+					fmt.Printf("  Extra Data: %s\n", string(block.Extra()))
 
 					if cfg.ExpectedExtraData != "" {
-						expectedHex := hex.EncodeToString([]byte(cfg.ExpectedExtraData))
-						if extraHex != expectedHex {
+						if !bytes.Equal(block.Extra(), []byte(cfg.ExpectedExtraData)) {
 							fmt.Printf("  Extra Data check: failed\n")
-							return fmt.Errorf("extra data mismatch: expected 0x%s (%q), got 0x%s", expectedHex, cfg.ExpectedExtraData, extraHex)
+							return fmt.Errorf("extra data mismatch: expected %q", cfg.ExpectedExtraData)
 						}
 						fmt.Printf("  Extra Data check: passed\n")
 					}