cmd/pushtx: fix gas price 0 rejection, show gas price in summary, print raw hex on error

Co-authored-by: drQedwards <213266729+drQedwards@users.noreply.github.com>

cmd/pushtx/main.go

@@ -105,6 +105,9 @@ func run(args []string, stdin io.Reader) error {
 	// Send to the RPC endpoint.
 	hash, err := sendRawTransaction(rpcURL, rawTx)
 	if err != nil {
+		// Still print the raw hex so the user can submit it elsewhere
+		// (e.g. etherscan.io/pushTx).
+		fmt.Println("Raw tx:", txHex)
 		return fmt.Errorf("sending transaction: %w", err)
 	}
 	fmt.Println("Transaction submitted successfully")
@@ -112,7 +115,7 @@ func run(args []string, stdin io.Reader) error {
 
 	// Print the raw hex transaction as the last output for easy
 	// copy-paste into block explorers like etherscan.io/pushTx.
-	fmt.Println("Raw tx: 0x" + hex.EncodeToString(rawTx))
+	fmt.Println("Raw tx:", txHex)
 	return nil
 }
 
@@ -152,6 +155,7 @@ func printTxSummary(tx *types.Transaction) {
 	fmt.Println("  Nonce:    ", tx.Nonce())
 	fmt.Println("  Value:    ", formatWei(tx.Value()))
 	fmt.Println("  Gas limit:", tx.Gas())
+	fmt.Println("  Gas price:", formatGwei(tx.GasPrice()))
 	fmt.Println("  Chain ID: ", tx.ChainId())
 }
 
@@ -165,6 +169,15 @@ func formatWei(wei *big.Int) string {
 	return fmt.Sprintf("%s wei (%s ETH)", wei.String(), ether.Text('f', 18))
 }
 
+// formatGwei converts a wei gas price to a human-readable string in Gwei.
+func formatGwei(wei *big.Int) string {
+	if wei == nil || wei.Sign() == 0 {
+		return "0 wei (0 Gwei)"
+	}
+	gwei := new(big.Float).Quo(new(big.Float).SetInt(wei), new(big.Float).SetFloat64(1e9))
+	return fmt.Sprintf("%s wei (%s Gwei)", wei.String(), gwei.Text('f', 9))
+}
+
 func printUsage() {
 	fmt.Fprintf(os.Stderr, `Usage: pushtx [--rpc URL] <tx-hex>
 

cmd/pushtx/main_test.go

@@ -49,7 +49,7 @@ func signedTestTxWithKey(t *testing.T, key *ecdsa.PrivateKey) (*types.Transactio
 
 	tx := types.NewTx(&types.LegacyTx{
 		Nonce:    6,
-		GasPrice: big.NewInt(0),
+		GasPrice: big.NewInt(1_000_000_000), // 1 Gwei – real networks reject gas price 0
 		Gas:      21055,
 		To:       addrPtr(common.HexToAddress("0x78b5290269740033b05bd8d71c97331295eb5918")),
 		Value:    new(big.Int).Mul(big.NewInt(10), big.NewInt(1e18)), // 10 ETH
@@ -149,12 +149,33 @@ func TestRunRPCError(t *testing.T) {
 	defer srv.Close()
 
 	_, txHex := signedTestTx(t)
-	err := run([]string{"--rpc", srv.URL, txHex}, strings.NewReader(""))
-	if err == nil {
+
+	// Capture stdout – raw hex should still be printed on RPC failure.
+	oldStdout := os.Stdout
+	r, w, err := os.Pipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+	os.Stdout = w
+
+	runErr := run([]string{"--rpc", srv.URL, txHex}, strings.NewReader(""))
+
+	w.Close()
+	os.Stdout = oldStdout
+
+	if runErr == nil {
 		t.Fatal("expected error, got nil")
 	}
-	if !strings.Contains(err.Error(), "already known") {
-		t.Fatalf("unexpected error message: %v", err)
+	if !strings.Contains(runErr.Error(), "already known") {
+		t.Fatalf("unexpected error message: %v", runErr)
+	}
+
+	out, err := io.ReadAll(r)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(string(out), "Raw tx: 0x") {
+		t.Fatal("expected raw hex in output even on RPC error")
 	}
 }
 
@@ -233,6 +254,24 @@ func TestFormatWei(t *testing.T) {
 	}
 }
 
+func TestFormatGwei(t *testing.T) {
+	tests := []struct {
+		wei  *big.Int
+		want string
+	}{
+		{nil, "0 wei (0 Gwei)"},
+		{big.NewInt(0), "0 wei (0 Gwei)"},
+		{big.NewInt(1_000_000_000), "1000000000 wei (1.000000000 Gwei)"},
+		{big.NewInt(20_000_000_000), "20000000000 wei (20.000000000 Gwei)"},
+	}
+	for _, tt := range tests {
+		got := formatGwei(tt.wei)
+		if got != tt.want {
+			t.Errorf("formatGwei(%v) = %q, want %q", tt.wei, got, tt.want)
+		}
+	}
+}
+
 func TestRunEqualsSyntax(t *testing.T) {
 	srv := fakeRPC(t, false)
 	defer srv.Close()