test(contracts): re-organize smart contract tests in separate files

Currently all tests related to a Poll were inside one file (MACI.test) - these tests have been moved
into their respective files, re organized and cleaned up, and a small number of test cases were
added which were missing.

contracts/contracts/Poll.sol

@@ -98,7 +98,7 @@ contract PollFactory is Params, IPubKey, Ownable, PollDeploymentParams {
 contract Poll is Params, Utilities, SnarkCommon, Ownable, PollDeploymentParams, EmptyBallotRoots {
   using SafeERC20 for ERC20;
 
-  bool internal isInit = false;
+  bool public isInit;
   // The coordinator's public key
   PubKey public coordinatorPubKey;
 

contracts/package.json

@@ -13,6 +13,9 @@
     "postbuild": "cp -r ./artifacts ./build",
     "test": "hardhat test",
     "test-maci": "hardhat test ./tests/MACI.test.ts",
+    "test-poll": "hardhat test ./tests/Poll.test.ts",
+    "test-messageProcessor": "hardhat test ./tests/MessageProcessor.test.ts",
+    "test-tally": "hardhat test ./tests/Tally.test.ts",
     "test-hasher": "hardhat test ./tests/Hasher.test.ts",
     "test-domainObjs": "hardhat test ./tests/DomainObjs.test.ts",
     "test-signupGatekeeper": "hardhat test ./tests/SignUpGatekeeper.test.ts",

contracts/tests/Hasher.test.ts

@@ -5,8 +5,6 @@ import { sha256Hash, hashLeftRight, hash3, hash4, hash5, genRandomSalt } from "m
 import { deployPoseidonContracts, linkPoseidonLibraries } from "../ts/deploy";
 import { Hasher } from "../typechain-types";
 
-require("module-alias/register");
-
 describe("Hasher", () => {
   let hasherContract: Hasher;