Add test for erc20 read properties

Author: janndriessen

Tests/web3swiftTests/localTests/ERC20ClassTests.swift

@@ -49,4 +49,16 @@ class ERC20ClassTests: LocalTestCase {
         XCTAssert(String(balance) == "1024")
         XCTAssert(allowance == 0)
     }
+
+    func testERC20ReadProperties() async throws {
+        let (web3, _, receipt, _) = try await TestHelpers.localDeployERC20()
+        let erc20token = ERC20.init(web3: web3, provider: web3.provider, address: receipt.contractAddress!)
+        try await erc20token.readProperties()
+        let decimals = erc20token.decimals()
+        let name = erc20token.name()
+        let symbol = erc20token.symbol()
+        XCTAssertEqual(decimals, 18)
+        XCTAssertEqual(name, "web3swift")
+        XCTAssertEqual(symbol, "w3s")
+    }
 }