add dummy test

.gitattributes

@@ -0,0 +1 @@
+*.sol linguist-language=Solidity

.vscode/launch.json

@@ -0,0 +1,16 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "node",
+            "request": "launch",
+            "name": "Mocha All",
+            "program": "${workspaceFolder}/contracts/node_modules/truffle/build/cli.bundled.js",
+            "args": ["test"],
+            "cwd": "${workspaceFolder}/contracts"
+        }
+    ]
+}

contracts/.editorconfig

@@ -0,0 +1,9 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 2
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true

contracts/README.md

@@ -0,0 +1,4 @@
+## Testing
+1. `npm i`
+2. `npx truffle compile`
+3. `npx truffle test` - it may fail for the first time, just run one more time.

contracts/contracts/MerkleTreeWithHistory.sol

@@ -8,11 +8,11 @@ contract MerkleTreeWithHistory {
   uint8 levels;
 
   uint8 constant ROOT_HISTORY_SIZE = 100;
-  uint256[] public roots;
+  uint256[] private _roots;
   uint256 public current_root = 0;
 
-  uint256[] public filled_subtrees;
-  uint256[] public zeros;
+  uint256[] private _filled_subtrees;
+  uint256[] private _zeros;
 
   uint32 public next_index = 0;
 
@@ -21,19 +21,19 @@ contract MerkleTreeWithHistory {
   constructor(uint8 tree_levels, uint256 zero_value) public {
     levels = tree_levels;
 
-    zeros.push(zero_value);
-    filled_subtrees.push(zeros[0]);
+    _zeros.push(zero_value);
+    _filled_subtrees.push(_zeros[0]);
 
     for (uint8 i = 1; i < levels; i++) {
-      zeros.push(HashLeftRight(zeros[i-1], zeros[i-1]));
-      filled_subtrees.push(zeros[i]);
+      _zeros.push(hashLeftRight(_zeros[i-1], _zeros[i-1]));
+      _filled_subtrees.push(_zeros[i]);
     }
 
-    roots = new uint256[](ROOT_HISTORY_SIZE);
-    roots[0] = HashLeftRight(zeros[levels - 1], zeros[levels - 1]);
+    _roots = new uint256[](ROOT_HISTORY_SIZE);
+    _roots[0] = hashLeftRight(_zeros[levels - 1], _zeros[levels - 1]);
   }
 
-  function HashLeftRight(uint256 left, uint256 right) public pure returns (uint256 mimc_hash) {
+  function hashLeftRight(uint256 left, uint256 right) public pure returns (uint256 mimc_hash) {
     uint256 k = 21888242871839275222246405745257275088548364400416034343698204186575808495617;
     uint256 R = 0;
     uint256 C = 0;
@@ -47,7 +47,7 @@ contract MerkleTreeWithHistory {
     mimc_hash = R;
   }
 
-  function insert(uint256 leaf) internal {
+  function _insert(uint256 leaf) internal {
     uint32 leaf_index = next_index;
     uint32 current_index = next_index;
     next_index += 1;
@@ -59,38 +59,38 @@ contract MerkleTreeWithHistory {
     for (uint8 i = 0; i < levels; i++) {
       if (current_index % 2 == 0) {
         left = current_level_hash;
-        right = zeros[i];
+        right = _zeros[i];
 
-        filled_subtrees[i] = current_level_hash;
+        _filled_subtrees[i] = current_level_hash;
       } else {
-        left = filled_subtrees[i];
+        left = _filled_subtrees[i];
         right = current_level_hash;
       }
 
-      current_level_hash = HashLeftRight(left, right);
+      current_level_hash = hashLeftRight(left, right);
 
       current_index /= 2;
     }
 
     current_root = (current_root + 1) % ROOT_HISTORY_SIZE;
-    roots[current_root] = current_level_hash;
+    _roots[current_root] = current_level_hash;
 
     emit LeafAdded(leaf, leaf_index);
   }
 
-  function isKnownRoot(uint _root) internal view returns(bool) {
-    if (_root == 0) {
+  function isKnownRoot(uint root) public view returns(bool) {
+    if (root == 0) {
       return false;
     }
     // search most recent first
     uint256 i;
     for(i = current_root; i >= 0; i--) {
-      if (_root == roots[i]) {
+      if (root == _roots[i]) {
         return true;
       }
     }
     for(i = ROOT_HISTORY_SIZE - 1; i > current_root; i--) {
-      if (_root == roots[i]) {
+      if (root == _roots[i]) {
         return true;
       }
     }
@@ -98,7 +98,19 @@ contract MerkleTreeWithHistory {
   }
 
   function getLastRoot() public view returns(uint256) {
-    return roots[current_root];
+    return _roots[current_root];
+  }
+
+  function roots() public view returns(uint256[] memory) {
+    return _roots;
+  }
+
+  function filled_subtrees() public view returns(uint256[] memory) {
+    return _filled_subtrees;
+  }
+
+  function zeros() public view returns(uint256[] memory) {
+    return _zeros;
   }
 }
 

contracts/contracts/Mixer.sol

@@ -24,7 +24,7 @@ contract Mixer is MerkleTreeWithHistory {
 
   function deposit(uint256 commitment) public payable {
     require(msg.value == transferValue, "Please send `transferValue` ETH along with transaction");
-    insert(commitment);
+    _insert(commitment);
     emit Deposit(msg.sender, commitment);
   }
 

contracts/contracts/Mocks/MerkleTreeWithHistoryMock.sol

@@ -0,0 +1,12 @@
+pragma solidity ^0.5.8;
+
+import '../MerkleTreeWithHistory.sol';
+
+contract MerkleTreeWithHistoryMock is MerkleTreeWithHistory {
+
+  constructor (uint8 tree_levels, uint256 zero_value) MerkleTreeWithHistory(tree_levels, zero_value) public {}
+
+  function insert(uint256 leaf) public {
+      _insert(leaf);
+  }
+}

contracts/migrations/2_deploy_mimc.js

@@ -0,0 +1,24 @@
+const path = require('path');
+
+const mimcGenContract = require('circomlib/src/mimcsponge_gencontract.js');
+const Artifactor = require('truffle-artifactor');
+
+const SEED = 'mimcsponge';
+
+
+module.exports = function(deployer) {
+  return deployer.then( async () =>  {
+    const contractsDir = path.join(__dirname, '..', 'build/contracts');
+    let artifactor = new Artifactor(contractsDir);
+    let mimcContractName = 'MiMC';
+    await artifactor.save({
+      contractName: mimcContractName,
+      abi: mimcGenContract.abi,
+      unlinked_binary: mimcGenContract.createCode(SEED, 220),
+    })
+    .then(async () => {
+      const MiMC = artifacts.require(mimcContractName);
+      await deployer.deploy(MiMC);
+    });
+  });
+};

contracts/package.json

@@ -13,6 +13,14 @@
   "author": "",
   "license": "ISC",
   "dependencies": {
-    "openzeppelin-solidity": "^2.3.0"
+    "bn-chai": "^1.0.1",
+    "chai": "^4.2.0",
+    "chai-as-promised": "^7.1.1",
+    "circomlib": "git+https://github.com/kobigurk/circomlib.git#323966c0584bafebf9652681c44d9ea348fe9bb5",
+    "ganache-cli": "^6.4.5",
+    "openzeppelin-solidity": "^2.3.0",
+    "truffle": "^5.0.20",
+    "truffle-artifactor": "^4.0.22",
+    "web3-utils": "^1.0.0-beta.55"
   }
 }

contracts/scripts/ganacheHelper.js

@@ -0,0 +1,45 @@
+function send(method, params = []) {
+  return new Promise((resolve, reject) => {
+    web3.currentProvider.send({
+      jsonrpc: '2.0',
+      id: Date.now(),
+      method,
+      params
+    }, (err, res) => {
+      return err ? reject(err) : resolve(res);
+    });
+  });
+}
+
+const takeSnapshot = async seconds => {
+  return await send('evm_snapshot');
+}
+
+const revertSnapshot = async (id) => {
+  await send('evm_revert', [id]);
+}
+
+const mineBlock = async (timestamp) => {
+  await send('evm_mine', [timestamp]);
+}
+
+const increaseTime = async (seconds) => {
+  await send('evm_increaseTime', [seconds]);
+}
+
+const minerStop = async () => {
+  await send('miner_stop', []);
+}
+
+const minerStart = async () => {
+  await send('miner_start', []);
+}
+
+module.exports = {
+  takeSnapshot,
+  revertSnapshot,
+  mineBlock,
+  minerStop,
+  minerStart,
+  increaseTime,
+};

contracts/test/MerkleTreeWithHistory.test.js

@@ -0,0 +1,71 @@
+const should = require('chai')
+  .use(require('bn-chai')(web3.utils.BN))
+  .use(require('chai-as-promised'))
+.should()
+
+const { toWei, toBN } = require('web3-utils')
+const { takeSnapshot, revertSnapshot, increaseTime } = require('../scripts/ganacheHelper');
+
+const MerkleTreeWithHistory = artifacts.require('./MerkleTreeWithHistoryMock.sol')
+const MiMC = artifacts.require('./MiMC.sol')
+
+function BNArrayToStringArray(array) {
+  const arrayToPrint = []
+  array.forEach(item => {
+    arrayToPrint.push(item.toString())
+  })
+  return arrayToPrint
+}
+
+contract('MerkleTreeWithHistory', async accounts => {
+  let merkleTreeWithHistory
+  let miMC
+  const sender = accounts[0]
+  const emptyAddress = '0x0000000000000000000000000000000000000000'
+  const levels = 5
+  const zeroValue = 1337
+  let snapshotId
+
+  before(async () => {
+    miMC = MiMC.deployed()
+    await MerkleTreeWithHistory.link(MiMC, miMC.address);
+    merkleTreeWithHistory = await MerkleTreeWithHistory.new(levels, zeroValue)
+    snapshotId = await takeSnapshot()
+  })
+
+  describe('#constuctor', async () => {
+    it('should initialize', async () => {
+      const filled_subtrees = await merkleTreeWithHistory.filled_subtrees()
+      console.log('filled_subtrees', BNArrayToStringArray(filled_subtrees))
+      const root = await merkleTreeWithHistory.getLastRoot()
+      console.log('root', root.toString())
+      filled_subtrees[0].should.be.eq.BN(zeroValue)
+      const zeros = await merkleTreeWithHistory.zeros()
+      // console.log('zeros', BNArrayToStringArray(zeros))
+      zeros[0].should.be.eq.BN(zeroValue)
+      const roots = await merkleTreeWithHistory.roots()
+      // console.log('roots', BNArrayToStringArray(roots))
+    })
+  })
+
+  describe('#insert', async () => {
+    it('should insert', async () => {
+      let filled_subtrees
+      let root
+
+      for (i = 1; i < 11; i++) {
+        await merkleTreeWithHistory.insert(i)
+        filled_subtrees = await merkleTreeWithHistory.filled_subtrees()
+        console.log('filled_subtrees', BNArrayToStringArray(filled_subtrees))
+        root = await merkleTreeWithHistory.getLastRoot()
+        console.log('root', root.toString())
+      }
+
+    })
+  })
+
+  afterEach(async () => {
+    await revertSnapshot(snapshotId.result)
+    snapshotId = await takeSnapshot()
+  })
+})

contracts/truffle-config.js

@@ -87,13 +87,13 @@ module.exports = {
     solc: {
       version: "0.5.8",    // Fetch exact version from solc-bin (default: truffle's version)
       // docker: true,        // Use "0.5.1" you've installed locally with docker (default: false)
-      // settings: {          // See the solidity docs for advice about optimization and evmVersion
-      //  optimizer: {
-      //    enabled: false,
-      //    runs: 200
-      //  },
+      settings: {          // See the solidity docs for advice about optimization and evmVersion
+       optimizer: {
+         enabled: false,
+         runs: 200
+       },
        // evmVersion: "byzantium"
-      // }
+      }
     }
   }
 }