Validate number sign in AbstractInt (#2406)

packages/types/src/codec/AbstractInt.ts

@@ -6,7 +6,7 @@ import { H256 } from '../interfaces/runtime';
 import { AnyNumber, Codec, Registry } from '../types';
 
 import BN from 'bn.js';
-import { assert, bnToBn, bnToHex, bnToU8a, formatBalance, formatNumber, hexToBn, isHex, isString, isU8a, u8aToBn } from '@polkadot/util';
+import { BN_ZERO, assert, bnToBn, bnToHex, bnToU8a, formatBalance, formatNumber, hexToBn, isHex, isString, isU8a, u8aToBn } from '@polkadot/util';
 import { blake2AsU8a } from '@polkadot/util-crypto';
 
 import Raw from './Raw';
@@ -77,6 +77,7 @@ export default abstract class AbstractInt extends BN implements Codec {
     this.#isHexJson = isHexJson;
     this.#isSigned = isSigned;
 
+    assert(isSigned || this.gte(BN_ZERO), `${this.toRawType()}: Negative number passed to unsigned type`);
     assert(super.bitLength() <= bitLength, `${this.toRawType()}: Input too large. Found input with ${super.bitLength()} bits, expected ${bitLength}`);
   }
 

packages/types/src/codec/UInt.spec.ts

@@ -16,6 +16,12 @@ describe('UInt', (): void => {
     ).toThrow('u32: Input too large. Found input with 164 bits, expected 32');
   });
 
+  it('fails on negative numbers', (): void => {
+    expect(
+      (): UInt => new UInt(registry, -123, 32)
+    ).toThrow('u32: Negative number passed to unsigned type');
+  });
+
   it('allows for construction via BigInt', (): void => {
     expect(
       new UInt(registry, 123456789123456789123456789n, 128).toHuman()