Fix token amount parsing

Author: DOBEN

packages/sdk/CHANGELOG.md

@@ -49,6 +49,10 @@
 
 ## 10.0.0-alpha.? (Unreleased)
 
+### Fixed
+
+- Fix conversion in `TokenAmount.fromDecimals` function when used with large `tokenAmount` values with small `decimal` values.
+
 ## 10.0.0-alpha.15
 
 ### Fixed

packages/sdk/src/plt/TokenAmount.ts

@@ -163,8 +163,7 @@ export function fromDecimal(amount: BigSource | bigint, decimals: number): Token
     }
 
     const bigAmount = Big(parsed);
-    const parsedDecimals = bigAmount.toString().split('.')[1]?.length ?? 0;
-
+    const parsedDecimals = bigAmount.toFixed(0).split('.')[1]?.length ?? 0;
     if (parsedDecimals > decimals) {
         throw new Error('The amount has more decimal places than the specified decimals.');
     }

packages/sdk/test/ci/plt/TokenAmount.test.ts

@@ -26,7 +26,15 @@ describe('PLT TokenAmount', () => {
 
     test('Token amounts with invalid values throws', () => {
         expect(() => TokenAmount.create(-504n, 0)).toThrow(TokenAmount.Err.negative());
+        expect(() => TokenAmount.create(-504n, 1)).toThrow(TokenAmount.Err.negative());
+        expect(() => TokenAmount.fromDecimal(-504n, 0)).toThrow(TokenAmount.Err.negative());
+        expect(() => TokenAmount.fromDecimal(-504n, 1)).toThrow(TokenAmount.Err.negative());
         expect(() => TokenAmount.create(MAX_U64 + 1n, 0)).toThrow(TokenAmount.Err.exceedsMaxValue());
+        expect(() => TokenAmount.create(99999999999999999999999999n, 1)).toThrow(TokenAmount.Err.exceedsMaxValue());
+        expect(() => TokenAmount.fromDecimal(MAX_U64 + 1n, 0)).toThrow(TokenAmount.Err.exceedsMaxValue());
+        expect(() => TokenAmount.fromDecimal(99999999999999999999999999n, 1)).toThrow(
+            TokenAmount.Err.exceedsMaxValue()
+        );
     });
 
     test('Returns expected amount', () => {