chore: add method to check allowance

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@descent-protocol/sdk",
-  "version": "0.1.20",
+  "version": "0.1.21",
   "description": "A Typescript library for interacting with the Descent Protocol",
   "keywords": [
     "xNGN",
@@ -18,7 +18,7 @@
   "main": "dist/index.js",
   "module": "dist/index.es.js",
   "browser": "dist/index.bundle.js",
-  "types": "./dist/types/index.d.ts",
+  "types": "./dist/types.d.ts",
   "exports": {
     ".": {
       "import": "./dist/esm/index.mjs",

src/index.ts

@@ -20,6 +20,7 @@ import {
   approveCurrencyToken,
   getCollateralTokenBalance,
   getCurrencyTokenBalance,
+  getCollateralTokenAllowance,
 } from './services/utility';
 
 export class DescentClass {
@@ -212,6 +213,22 @@ export class DescentClass {
     return result;
   }
 
+  /**
+   * @dev approve the vault to take a certain amount of collateral
+   * @param amount amount of allowance
+   * @returns tx object
+   */
+  public async collateralTokenAllowance(approver: string) {
+    const result = await getCollateralTokenAllowance(
+      this.collateral,
+      approver,
+      this.chainId,
+      this.signer,
+    );
+
+    return result;
+  }
+
   /**
    * @dev gets the xNGN balalnce of an address
    * @param owner address of the owner

src/services/utility.ts

@@ -100,14 +100,14 @@ const getCollateralTokenBalance = async (
 const getCollateralTokenAllowance = async (
   collateral: ICollateral,
   owner: string,
-  spender: string,
   chainId: string,
   signer: Signer,
 ) => {
   const collateralAddress: any = getContractAddress(collateral)[chainId];
+  const vaultAddress: any = getContractAddress('Vault')[chainId];
 
   const collateralContract = Contract(collateralAddress, USDC__factory.abi, signer);
-  const allowance = await collateralContract.allowance(owner, spender);
+  const allowance = await collateralContract.allowance(owner, vaultAddress);
   const formattedAllowance = formatUnits(allowance, 6);
   return formattedAllowance;
 };

test/utility.test.ts

@@ -39,4 +39,11 @@ describe('Descent Protocol Utility Test', () => {
     console.log(response);
     expect(response).toBeDefined();
   }, 2000000);
+
+  it('should check for token allowance on vault', async () => {
+    const response = await descent.collateralTokenAllowance(owner);
+    console.log(response);
+
+    expect(response).toBeDefined();
+  });
 });