我不熟悉测试，并且希望获得良好的代码覆盖率。
我的用户模型上有一个预保存的钩子，用于处理对哈希值进行哈希处理的操作，现在我只希望在修改了密码字段后才能运行该钩子。
如何测试if语句？是保存用户，更新用户然后再次保存并测试密码的情况吗？
另一个问题。最佳做法是什么？要将其用作用户模型上的预保存钩子或方法？
UserSchema.pre('save',async function(next) {
// Only run this function if password was modified
if (!this.isModified('password')) return next();
// Hash the password
this.password = await bcrypt.hash(this.password,12);
// Remove passwordConfirm field
this.passwordConfirm = undefined;
next();
});
这是单元测试解决方案：
index.js：
import { Schema } from 'mongoose';
import bcrypt from 'bcrypt';
const UserSchema = new Schema();
UserSchema.pre('save',userPreSaveHook);
export async function userPreSaveHook(next) {
// Only run this function if password was modified
if (!this.isModified('password')) return next();
// Hash the password
this.password = await bcrypt.hash(this.password,12);
// Remove passwordConfirm field
this.passwordConfirm = undefined;
next();
}
index.spec.js：
import { userPreSaveHook } from './';
describe('userPreSaveHook',() => {
test('should execute next middleware when password is modified',async () => {
const mNext = jest.fn();
const mContext = {
isModified: jest.fn()
};
mContext.isModified.mockReturnValueOnce(false);
await userPreSaveHook.call(mContext,mNext);
expect(mContext.isModified).toBeCalledWith('password');
expect(mNext).toBeCalledTimes(1);
});
test('should has password and remove passwordConfirm field',async () => {
const mNext = jest.fn();
const mContext = {
isModified: jest.fn(),passwordConfirm: 'aaa',password: '123456'
};
mContext.isModified.mockReturnValueOnce(true);
await userPreSaveHook.call(mContext,mNext);
expect(mContext.isModified).toBeCalledWith('password');
expect(mNext).toBeCalledTimes(1);
expect(mContext.passwordConfirm).toBeUndefined();
expect(mContext.password).not.toBe('123456');
});
});
覆盖率100％的单元测试结果：
PASS src/stackoverflow/58701700/index.spec.js (12.23s)
userPreSaveHook
✓ should execute next middleware when password is modified (9ms)
✓ should has password and remove passwordConfirm field (295ms)
----------|----------|----------|----------|----------|-------------------|
File | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s |
----------|----------|----------|----------|----------|-------------------|
All files | 100 | 100 | 100 | 100 | |
index.js | 100 | 100 | 100 | 100 | |
----------|----------|----------|----------|----------|-------------------|
Test Suites: 1 passed,1 total
Tests: 2 passed,2 total
Snapshots: 0 total
Time: 12.689s,estimated 14s
源代码：https://github.com/mrdulin/jest-codelab/tree/master/src/stackoverflow/58701700