From d227141c38b7a2fffa9d09d73631627d6d8f5e1c Mon Sep 17 00:00:00 2001
From: Chris Duncan <chris@codecow.com>
Date: Mon, 3 Aug 2026 12:36:45 -0700
Subject: [PATCH] Improve account derivation range checks.

---
 src/lib/wallet/accounts.ts | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/lib/wallet/accounts.ts b/src/lib/wallet/accounts.ts
index 9d380de..65f79e2 100644
--- a/src/lib/wallet/accounts.ts
+++ b/src/lib/wallet/accounts.ts
@@ -11,10 +11,19 @@ export async function _accounts (type: WalletType, accounts: Map<number, Account
 export async function _accounts (type: WalletType, accounts: Map<number, Account>, vault: Vault, from: unknown, to?: unknown): Promise<Account | Map<number, Account>> {
 	const isSingle = to === undefined
 	to ??= from
-	if (typeof from !== 'number' || typeof to !== 'number') {
-		throw new TypeError('Invalid account range', { cause: `${from}-${to}` })
+	if (typeof from !== 'number') {
+		throw new Error('Invalid account range start argument', { cause: `${typeof from} ${from}` })
+	}
+	if (typeof to !== 'number') {
+		throw new Error('Invalid account range end argument', { cause: `${typeof to} ${to}` })
 	}
 	if (from > to) [from as number, to as number] = [to, from]
+	if (from < 0 || 0xffffffff < from || to < 0 || 0xffffffff < to) {
+		throw new TypeError('Invalid account range', { cause: `${from}-${to}` })
+	}
+	if (to - from > 100) {
+		console.warn(`libnemo performance may degrade when deriving many accounts at once`)
+	}
 	const output = new Map<number, Account>()
 	const indexes: number[] = []
 	for (let i = from; i <= to; i++) {
-- 
2.52.0