fix: force s-value normalization

Should fix flaky tests

Author: cpb8010

examples/demo-app/components/WalletConfig.vue

@@ -252,7 +252,7 @@ watch(isReady, (ready) => {
   if (config.value.source === "browser-wallet") {
     config.value.connectedAddress = connectedAddress.value;
   }
-});
+}, { immediate: true, flush: "sync" });
 
 /**
  * Connect to browser wallet (MetaMask, etc.)
@@ -317,9 +317,10 @@ function handleAccountsChanged(accounts) {
 }
 
 /**
- * Detect network environment
+ * Detect network environment and check for query parameters
  */
 async function detectEnvironment() {
+  // First, detect if we're on Anvil
   try {
     const response = await fetch("/contracts.json");
     if (response.ok) {
@@ -338,6 +339,24 @@ async function detectEnvironment() {
     // eslint-disable-next-line no-console
     console.warn("Could not load contracts.json:", err);
   }
+
+  // Then, check for fundingAccount query parameter (for E2E tests)
+  // This must happen after we've detected isAnvil
+  if (typeof window !== "undefined") {
+    const urlParams = new URLSearchParams(window.location.search);
+    const fundingAccountParam = urlParams.get("fundingAccount");
+    if (fundingAccountParam !== null) {
+      const accountIndex = parseInt(fundingAccountParam, 10);
+      if (!isNaN(accountIndex) && accountIndex >= 0 && accountIndex <= 9) {
+        // eslint-disable-next-line no-console
+        console.log("Setting Anvil account from query parameter:", accountIndex);
+        config.value.source = "anvil";
+        config.value.anvilAccountIndex = accountIndex;
+        // Since isAnvil might already be true from detectEnvironment,
+        // the isReady computed property should now evaluate to true
+      }
+    }
+  }
 }
 
 // Initialize on mount

packages/sdk-platforms/web/src/webauthn-helpers.ts

@@ -101,6 +101,31 @@ function parseDerSignature(signatureBytes: Uint8Array): { r: Uint8Array; s: Uint
     throw new Error(`Invalid signature component length: r=${r.length}, s=${s.length}`);
   }
 
+  // Normalize s to low-s form for EVM compatibility
+  // secp256r1 curve order (n): 0xFFFFFFFF00000000FFFFFFFFFFFFFFFFBCE6FAADA7179E84F3B9CAC2FC632551
+  const secp256r1_n = BigInt("0xFFFFFFFF00000000FFFFFFFFFFFFFFFFBCE6FAADA7179E84F3B9CAC2FC632551");
+  const secp256r1_n_half = secp256r1_n / 2n;
+
+  // Convert s to BigInt
+  let sBigInt = 0n;
+  for (let i = 0; i < s.length; i++) {
+    sBigInt = (sBigInt << 8n) | BigInt(s[i]);
+  }
+
+  // If s > n/2, use n - s instead (low-s form)
+  if (sBigInt > secp256r1_n_half) {
+    sBigInt = secp256r1_n - sBigInt;
+
+    // Convert back to Uint8Array
+    const sBytes: number[] = [];
+    let temp = sBigInt;
+    while (temp > 0n) {
+      sBytes.unshift(Number(temp & 0xFFn));
+      temp = temp >> 8n;
+    }
+    s = new Uint8Array(sBytes);
+  }
+
   return { r, s };
 }