javascript - Node.js - Mocha did() 方法在之前的测试中导致错误

Question

我正在使用 Chai 来实现 Mocha 作为我在 Node.js 中编写的应用程序的测试框架。此规范是为 secureId.js 编写的。

// secureId.js
"use strict"

const bcrypt = require('bcrypt');

// Constructor for SecureID
function SecureID(str, rounds, func) {
  // Makes salt and hash unable to be changed or viewed outside the member functions
  let hashedID;
  let gennedSalt;

  bcrypt.genSalt(rounds, (err, salt) => {
    gennedSalt = salt;

    bcrypt.hash(str, salt, (err, hash) => {
        hashedID = hash;
        func(err, salt, hash);
    });
  });

  // Gets the salt associated with the instance
  this.getSalt = function() {
    return gennedSalt;
  };

  // Gets the hash associated with the instance
  this.getHash = function() {
    return hashedID;
  };

  // Set new id for already instantiated SecureID
  this.setNewId = function(str, rounds, func) {
    bcrypt.genSalt(rounds, function(err, salt) {
      gennedSalt = salt;

      if (err)
        func(err);

      bcrypt.hash(str, salt, function(err, hash) {
        hashedID = hash;
        func(err, salt, hash);
      });
    });
  };

  // set new id for already instantiated SecureID synchronously
  this.setNewIdSync = function(str, rounds) {
    gennedSalt = bcrypt.genSaltSync(rounds);
    hashedID = bcrypt.hashSync(str, gennedSalt);
  };

  // Compares a string and hash
  this.equals = function(str, func) {
    bcrypt.compare(str, hashedID, function(err, res) {
      func(err, res);
    });
  };

  // Compares a string and hash synchronously
  this.equalsSync = function(str) {
      return bcrypt.compareSync(str, hashedID);
  };
};

exports.SecureID = SecureID;

这是规范。

"use strict";

let expect = require('chai').expect;

describe('SecureID', () => {
  let ids = [];
  let anID = 'aLongIDofCharacters';
  let anAmountOfRounds = 10;
  let SecureID = require('../secureId').SecureID;

  console.log(`Tests with rounds >= 20 will take over an hour to complete. You are doing ${anAmountOfRounds} round(s).`);

  describe('#SecureID()', () => {
    let i = 0;
    let checkingFunction = (done) => {
      if (i == 2) {
        clearInterval(checkingFunction);
        done();
      };
    };

    it('Create an ID', (done) => {
      for (let j = 0; j <= 1; j++) {
        ids.push(new SecureID(anID, anAmountOfRounds, (err, salt, hash) => {
          expect(err).to.be.undefined;
          expect(salt).not.to.be.undefined;
          expect(hash).not.to.be.undefined;
          i++;
        }));
      };

      setInterval(checkingFunction, 100, done);
    });
  });

  describe('#getHash()', () => {
    it('Returns a hash.', () => {
      expect(ids[0].getHash()).not.to.be.undefined;
      expect(ids[1].getHash()).not.to.be.undefined;
    });

    it('Returns a hash unique to that generated from the same ID.', () => {
      expect(ids[0].getHash()).not.to.equal(ids[1].getHash());
    });
  });

  describe('#getSalt()', () => {
    it('Returns a salt.', () => {
      expect(ids[0].getSalt()).not.to.be.undefined;
      expect(ids[1].getSalt()).not.to.be.undefined;
    });

    it('Returns a salt unique to that generated from the same ID.', () => {
      expect(ids[1].getSalt()).not.to.equal(ids[0].getSalt());
    });
  });

  describe('#setNewId()', () => {
    let i = 0;
    let checkingFunction = (done) => {
      if (i == 2) {
        clearInterval(checkingFunction);
        done();
      };
    };

    it('Sets a new ID asynchronously.', (done) => {
      for (let j = 0; j <= 1; j++) {
        ids[j].setNewId(anID, (err, salt, hash) => {
          let previousHash = ids[j].getHash();
          let previousSalt = ids[j].getSalt();

          expect(err).to.be.undefined;
          expect(salt).not.to.equal(previousSalt);
          expect(hash).not.to.equal(previousHash);
          i++;
        });
      };

      setInterval(checkingFunction, 100, done);
    });
  });

  describe('#setNewIdSync()', () => {
    it('Sets a new ID synchronously.', () => {
      for (let j = 0; j <= 1; j++) {
        let previousHash = ids[j].getHash();
        let previousSalt = ids[j].getSalt();

        ids[j].setNewIdSync(anID);

        expect(ids[j].getSalt()).not.to.equal(previousSalt);
        expect(ids[j].getHash()).not.to.equal(previousHash);
      };
    });
  });

  describe('#equals()', () => {
    it('Compares an ID with a hash, calling a callback with the result of genHash(ID) == hash.', () => {
      it('Hash is not equal to an empty string.', (done) => {
        ids[0].equals('', (err, res) => {
          expect(res).to.equal(false);
          expect(err).to.be.undefined;
          done();
        });
      });

      it('Hash is equal to original ID.', (done) => {
        ids[0].equals(anID, (err, res) => {
          expect(res).to.equal(true);
          expect(err).to.be.undefined;
          done();
        });
      });
    });
  });

  describe('#equalsSync()', () => {
    it('Compares an ID with a hash, returning the result of genHash(ID) == hash (synchronous).', () => {
      it('Hash is not equal to an empty string.', () => {
        expect(ids[0].equalsSync('')).to.equal(false);
      });

      it('Hash is equal to original ID.', () => {
        expect(ids[0].equalsSync(anID)).to.equal(true);
      });
    });
  });
});

我的问题是，当我到达#setNewId()时，我得到测试失败的以下原因:done()被调用多次。我明白这个错误的意思，但我不明白的是，当Mocha输出测试结果时，当它到达#setNewId()时，它显示

1) Create an ID
✓ Sets a new ID asynchronously. (107 ms)

同样，#setNewIdSync() 会产生多次调用完成错误，但似乎是尝试验证#setNewId()；它在 Mocha 中的结果是

✓ Sets a new ID synchronously. (252 ms)
2) Sets a new ID asynchronously.

有什么帮助吗？我只是做了一些愚蠢的事情吗？

Answer 1

所以，事实证明我做了一些愚蠢的事情。这只是一个错误地清除间隔的问题。

之前的代码...

describe('#SecureID()', () => {
  let i = 0;
  let checkingFunction = (done) => {
    if (i == 2) {
      clearInterval(checkingFunction);
      done();
    };
  };

  it('Create an ID', (done) => {
    for (let j = 0; j <= 1; j++) {
      ids.push(new SecureID(anID, anAmountOfRounds, (err, salt, hash) => {
        expect(err).to.be.undefined;
        expect(salt).not.to.be.undefined;
        expect(hash).not.to.be.undefined;
        i++;
      }));
    };

    setInterval(checkingFunction, 100, done);
  });
});

当间隔checkingFunction不存在时尝试清除它。调用 setInterval(checkingFunction, ...) 将使用 checkingFunction 方法设置间隔，但是，名称为 checkingFunction 的所述间隔不存在。所以，修复实际上很简单:

describe('#setNewId()', () => {
  it('Sets a new ID asynchronously.', (done) => {
    let i = 0;
    let checkingInterval = setInterval( () => {
        if (i == 2) {
          clearInterval(checkingInterval);
          done();
        };
      }, 100);

    for (let j = 0; j <= 1; j++) {
      ids.push(new SecureID(anID, anAmountOfRounds, (err, salt, hash) => {
        expect(err).to.be.undefined;
        expect(salt).not.to.be.undefined;
        expect(hash).not.to.be.undefined;
        i++;
      }));
    };
  });
});

行 let checkingInterval = setInterval( () => { 创建一个名为 checkingInterval 的新间隔，稍后当异步测试完成时会在其内部清除。