Double voting unit test failing on Election dApp

Question

I am working through DApp University's election dApp tutorial. I made unit tests for invalid candidate, and double voting. My double voting unit test is failing, saying:

  1) Contract: Election
   throws an exception for double voting:
 AssertionError: error message must contain revert
  at test\election.js:78:7
  at process._tickCallback (internal/process/next_tick.js:68:7)

Here is my dApp's repository. https://github.com/Legitimate/election

This is my code for the double voting unit test. The line that is failing is found in the first unit test I made for invalid candidate. I'm not sure why it is failing for double voting. I would appreciate any consideration from the community. Thank you.

it("throws an exception for invalid candidate", function() {
    return Election.deployed().then(function(instance) {
      electionInstance = instance;
      return electionInstance.vote(99, { from: accounts[1] });
    }).then(assert.fail).catch(function(error) {
      assert(error.message.indexOf('revert') >= 0, "error message must contain revert");
      return electionInstance.candidates(1);
    }).then(function(candidate1) {
      var voteCount = candidate1[2];
      assert.equal(voteCount, 1, "candidate 1 did not receive any votes");
      return electionInstance.candidates(2);
    }).then(function(candidate2) {
      var voteCount = candidate2[2];
      assert.equal(voteCount, 0, "candidate 2 did not receive any votes");
    });
  });



it("throws an exception for double voting", function() {
    return Election.deployed().then(function(instance) {
      electionInstance = instance;
      candidateId = 2;
      electionInstance.vote(candidateId, { from: accounts[1] });
      return electionInstance.candidates(candidateId);
    }).then(function(candidate) {
      var VoteCount = candidate[2];
      assert.equal(voteCount, 1, "accepts first vote");
      // Try to vote again
      return electionInstance.vote(candidateId, { from: accounts[1] });
    }).then(assert.fail).catch(function(error) {
      assert(error.message.indexOf('revert') >= 0, "error message must contain revert");
      return electionInstance.candidates(1);
    }).then(function(candidate1) {
      var voteCount = candidate1[2];
      assert.equal(voteCount, 1, "candidate 1 did not receive any votes");
      return electionInstance.candidates(2);
    }).then(function(candidate2) {
      var voteCount = candidate2[2];
      assert.equal(voteCount, 1, "candidate 2 did not receive any votes");
    });
  });

Answer 1

var VoteCount = candidate[2];
assert.equal(voteCount, 1, "accepts first vote");

The assert.equal() is failing because the variable VoteCount is capitalized in the declaration but not in the assert. You are comparing null to 1.