add erc20 with configurable decimals (#113)

Author: elv-preethi

src/tradable/ElvToken.sol

@@ -8,13 +8,20 @@ import "@openzeppelin/contracts/access/AccessControlEnumerable.sol";
 import "./cmn/Roles.sol";
 
 contract ElvToken is ERC20, ERC20Burnable, Pausable, AccessControlEnumerable {
-    constructor(string memory name, string memory symbol, uint256 amount) ERC20(name, symbol) {
+
+    uint8 private tokenDecimal;
+    constructor(string memory name, string memory symbol, uint8 decimal, uint256 amount) ERC20(name, symbol) {
         _grantRole(DEFAULT_ADMIN_ROLE, msg.sender);
         _grantRole(ElvCmnRoles.PAUSER_ROLE, msg.sender);
+        tokenDecimal = decimal;
         _mint(msg.sender, amount * 10 ** decimals());
         _grantRole(ElvCmnRoles.MINTER_ROLE, msg.sender);
     }
 
+    function decimals() public view virtual override returns (uint8) {
+        return tokenDecimal;
+    }
+
     function pause() public onlyRole(ElvCmnRoles.PAUSER_ROLE) {
         _pause();
     }

test/elvToken/ElvToken.t.sol

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.13;
+
+import {console} from "forge-std/console.sol";
+import {Test} from "forge-std/Test.sol";
+import "src/tradable/ElvToken.sol";
+
+
+contract ERC20PaymentsTest is Test {
+    ElvToken internal token;
+    address public deployer;
+
+    function setUp() public virtual {
+        vm.prank(msg.sender, msg.sender);
+        deployer = msg.sender;
+        token = new ElvToken("ElvToken","ELV",6,20000);
+    }
+
+    function testDecimals() public{
+        assertEq(token.decimals(), 6);
+    }
+
+    function testTokenMinted() public {
+        assertEq(token.balanceOf(deployer), 20000 * 10 ** token.decimals());
+    }
+}

test/payments/ERC20Payments.t.sol

@@ -29,7 +29,7 @@ contract ERC20PaymentsTest is Test {
         carol = users[2];
         vm.label(carol, "Carol");
 
-        token = new ElvToken("ElvToken","ELV",20000000);
+        token = new ElvToken("ElvToken","ELV",18, 20000000);
         erc20Payments = new ERC20Payments();
     }