From 1505a41576e2f9033d57e80e7bbee8ff9f5e68a8 Mon Sep 17 00:00:00 2001
From: Otto Allmendinger <otto@bitgo.com>
Date: Wed, 11 Feb 2026 11:20:43 +0100
Subject: [PATCH 1/2] feat(wasm-utxo): add test for address encoding
 compatibility across coins

Test which coins share address formats for different script types.

Issue: BTC-2650

Co-authored-by: llm-git <llm-git@ttll.de>
---
 .../wasm-utxo/test/address/compatibility.ts   | 90 +++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100644 packages/wasm-utxo/test/address/compatibility.ts

diff --git a/packages/wasm-utxo/test/address/compatibility.ts b/packages/wasm-utxo/test/address/compatibility.ts
new file mode 100644
index 0000000..484ff8c
--- /dev/null
+++ b/packages/wasm-utxo/test/address/compatibility.ts
@@ -0,0 +1,90 @@
+import assert from "node:assert";
+import { address as addressNs } from "../../js/index.js";
+import { coinNames, type CoinName } from "../../js/coinName.js";
+
+/**
+ * For a given script, encode as an address for every coin.
+ * Returns groups of coins that produce the same address, sorted.
+ */
+function getCompatibilityGroups(scriptHex: string): CoinName[][] {
+  const script = Buffer.from(scriptHex, "hex");
+  const addressToCoins = new Map<string, CoinName[]>();
+
+  for (const coin of coinNames) {
+    try {
+      const addr = addressNs.fromOutputScriptWithCoin(script, coin);
+      const group = addressToCoins.get(addr);
+      if (group) {
+        group.push(coin);
+      } else {
+        addressToCoins.set(addr, [coin]);
+      }
+    } catch {
+      // coin does not support this script type
+    }
+  }
+
+  return Array.from(addressToCoins.values())
+    .map((g) => g.sort())
+    .sort((a, b) => a[0].localeCompare(b[0]));
+}
+
+// Representative scripts from test/fixtures/address/bitcoin.json
+const scripts = {
+  p2sh: "a91411510d2560794b3ed7bf734bc0e030e70e4db42d87",
+  p2shP2wsh: "a9140c4e25aa3282fa35888f5e1eedb876265328312587",
+  p2wsh: "00208bb2ef4181b60abe68b4c9cdc44c92e73bbb17fa2611e7e5b60d794794a1c94d",
+  p2tr: "5120c4beea12923f95c32976d3d1ca7d5490aa3ea28f96d5feacc8ecc28819925eb5",
+  p2trMusig2: "51205f98a79a3f750b250bee5bbdca0705db0ec8621f1bda91a083536a8a8bd6b6ed",
+};
+
+// p2sh and p2shP2wsh are both a914...87 scripts; the encoding cannot distinguish them,
+// so they produce the same compatibility groups.
+const legacyGroups: CoinName[][] = [
+  ["bch", "bcha", "bsv", "btc"],
+  ["btg"],
+  ["dash"],
+  ["doge"],
+  ["ltc"],
+  ["tbch", "tbcha", "tbsv", "tbtc", "tbtc4", "tbtcbgsig", "tbtcsig", "tbtg", "tdoge"],
+  ["tdash"],
+  ["tltc"],
+  ["tzec"],
+  ["zec"],
+];
+
+const segwitGroups: CoinName[][] = [
+  ["btc"],
+  ["btg"],
+  ["ltc"],
+  ["tbtc", "tbtc4", "tbtcbgsig", "tbtcsig"],
+  ["tbtg"],
+  ["tltc"],
+];
+
+const taprootGroups: CoinName[][] = [
+  ["btc"],
+  ["tbtc", "tbtc4", "tbtcbgsig", "tbtcsig"],
+];
+
+describe("address compatibility", function () {
+  it("p2sh: btc/bch/bcha/bsv share mainnet format, most testnets share testnet format", function () {
+    assert.deepStrictEqual(getCompatibilityGroups(scripts.p2sh), legacyGroups);
+  });
+
+  it("p2shP2wsh: same groups as p2sh (indistinguishable script structure)", function () {
+    assert.deepStrictEqual(getCompatibilityGroups(scripts.p2shP2wsh), legacyGroups);
+  });
+
+  it("p2wsh: btc/btg/ltc each have unique bech32 HRP, testnets likewise", function () {
+    assert.deepStrictEqual(getCompatibilityGroups(scripts.p2wsh), segwitGroups);
+  });
+
+  it("p2tr: only btc family supports taproot", function () {
+    assert.deepStrictEqual(getCompatibilityGroups(scripts.p2tr), taprootGroups);
+  });
+
+  it("p2trMusig2: same groups as p2tr (same bech32m encoding)", function () {
+    assert.deepStrictEqual(getCompatibilityGroups(scripts.p2trMusig2), taprootGroups);
+  });
+});

From 6dc5b5df292e66797c48690417c6e131922914f4 Mon Sep 17 00:00:00 2001
From: Otto Allmendinger <otto@bitgo.com>
Date: Wed, 11 Feb 2026 16:40:33 +0100
Subject: [PATCH 2/2] feat(wasm-utxo): export coinName utility functions

Export additional utility functions from coinName module to help with
network type checking and conversion.

Issue: BTC-2650

Co-authored-by: llm-git <llm-git@ttll.de>
---
 packages/wasm-utxo/js/index.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/wasm-utxo/js/index.ts b/packages/wasm-utxo/js/index.ts
index 69d3512..98b4aaa 100644
--- a/packages/wasm-utxo/js/index.ts
+++ b/packages/wasm-utxo/js/index.ts
@@ -22,7 +22,7 @@ export { ECPair } from "./ecpair.js";
 export { BIP32 } from "./bip32.js";
 export { Dimensions } from "./fixedScriptWallet/Dimensions.js";
 
-export type { CoinName } from "./coinName.js";
+export type { CoinName, getMainnet, isMainnet, isTestnet, isCoinName } from "./coinName.js";
 export type { Triple } from "./triple.js";
 export type { AddressFormat } from "./address.js";
 export type { TapLeafScript, PreparedInscriptionRevealData } from "./inscriptions.js";