Merge pull request #118 from BitGo/BTC-2980.export-testutils

feat(wasm-utxo): export testutils module, fix testutils browser compat

Author: OttoAllmendinger

packages/wasm-utxo/js/bip32.ts

@@ -97,6 +97,18 @@ export class BIP32 implements BIP32Interface {
     return new BIP32(wasm);
   }
 
+  /**
+   * Create a BIP32 master key from a string by hashing it with SHA256.
+   * Useful for deterministic test key generation.
+   * @param seedString - The seed string to hash
+   * @param network - Optional network string
+   * @returns A BIP32 instance
+   */
+  static fromSeedSha256(seedString: string, network?: string | null): BIP32 {
+    const wasm = WasmBIP32.from_seed_sha256(seedString, network);
+    return new BIP32(wasm);
+  }
+
   /**
    * Get the chain code as a Uint8Array
    */

packages/wasm-utxo/js/index.ts

@@ -14,6 +14,7 @@ export * as utxolibCompat from "./utxolibCompat.js";
 export * as fixedScriptWallet from "./fixedScriptWallet/index.js";
 export * as bip32 from "./bip32.js";
 export * as ecpair from "./ecpair.js";
+export * as testutils from "./testutils/index.js";
 
 // Only the most commonly used classes and types are exported at the top level for convenience
 export { ECPair } from "./ecpair.js";

packages/wasm-utxo/js/testutils/keys.ts

@@ -1,4 +1,3 @@
-import * as crypto from "crypto";
 import { BIP32 } from "../bip32.js";
 import { RootWalletKeys } from "../fixedScriptWallet/RootWalletKeys.js";
 import type { Triple } from "../triple.js";
@@ -17,7 +16,7 @@ import type { Triple } from "../triple.js";
  * ```
  */
 export function getKey(seed: string): BIP32 {
-  return BIP32.fromSeed(crypto.createHash("sha256").update(seed).digest());
+  return BIP32.fromSeedSha256(seed);
 }
 
 /**

packages/wasm-utxo/src/wasm/bip32.rs

@@ -210,6 +210,18 @@ impl WasmBIP32 {
         Ok(WasmBIP32(BIP32Key::Private(xpriv)))
     }
 
+    /// Create a BIP32 master key from a string by hashing it with SHA256.
+    /// This is useful for deterministic test key generation.
+    #[wasm_bindgen]
+    pub fn from_seed_sha256(
+        seed_string: &str,
+        network: Option<String>,
+    ) -> Result<WasmBIP32, WasmUtxoError> {
+        use crate::bitcoin::hashes::{sha256, Hash};
+        let hash = sha256::Hash::hash(seed_string.as_bytes());
+        Self::from_seed(&hash[..], network)
+    }
+
     /// Get the chain code as a Uint8Array
     #[wasm_bindgen(getter)]
     pub fn chain_code(&self) -> js_sys::Uint8Array {

packages/wasm-utxo/test/bip32.ts

@@ -1,4 +1,5 @@
 import * as assert from "assert";
+import * as crypto from "crypto";
 import { bip32 as utxolibBip32 } from "@bitgo/utxo-lib";
 import { BIP32 } from "../js/bip32.js";
 
@@ -138,6 +139,25 @@ describe("WasmBIP32", () => {
     assert.strictEqual(key.isNeutered(), false);
     assert.ok(key.toBase58().startsWith("tprv"));
   });
+
+  it("should create from seed string using SHA256", () => {
+    const seedString = "test";
+    const key = bip32.BIP32.fromSeedSha256(seedString);
+    assert.strictEqual(key.depth, 0);
+    assert.strictEqual(key.isNeutered(), false);
+    assert.ok(key.privateKey instanceof Uint8Array);
+    // Should be deterministic
+    const key2 = bip32.BIP32.fromSeedSha256(seedString);
+    assert.strictEqual(key.toBase58(), key2.toBase58());
+  });
+
+  it("should create from seed string with network", () => {
+    const seedString = "test";
+    const key = bip32.BIP32.fromSeedSha256(seedString, "BitcoinTestnet3");
+    assert.strictEqual(key.depth, 0);
+    assert.strictEqual(key.isNeutered(), false);
+    assert.ok(key.toBase58().startsWith("tprv"));
+  });
 });
 
 describe("WasmBIP32 parity with utxolib", () => {
@@ -336,4 +356,26 @@ describe("WasmBIP32 parity with utxolib", () => {
     const wasmParentFp = new DataView(wasmKey.fingerprint.buffer).getUint32(0, false);
     assert.strictEqual(wasmChild.parentFingerprint, wasmParentFp);
   });
+
+  it("should match utxolib when using fromSeedSha256", () => {
+    // Test various seed strings to ensure parity with manual SHA256 + fromSeed
+    const seedStrings = ["test", "user", "backup", "bitgo", "default.0", "default.1", "default.2"];
+
+    for (const seedString of seedStrings) {
+      // Manual approach: hash with SHA256, then create from seed
+      const hash = crypto.createHash("sha256").update(seedString).digest();
+      const utxolibKey = utxolibBip32.fromSeed(hash);
+
+      // WASM approach: fromSeedSha256 does hashing internally
+      const wasmKey = bip32.BIP32.fromSeedSha256(seedString);
+
+      assert.strictEqual(
+        wasmKey.toBase58(),
+        utxolibKey.toBase58(),
+        `Failed for seed string: ${seedString}`,
+      );
+      assert.ok(bufferEqual(wasmKey.publicKey, utxolibKey.publicKey));
+      assert.ok(bufferEqual(wasmKey.chainCode, utxolibKey.chainCode));
+    }
+  });
 });