## 配置ts jest
* 1 npm install --save-dev jest ts-jest @types/jest
* 2 Modify your project's package.json
```
"jest": {
  "transform": {
    "^.+\\.tsx?$": "ts-jest"
  },
  "testRegex": "(/__tests__/.*|(\\.|/)(test|spec))\\.(jsx?|tsx?)$",
  "moduleFileExtensions": [
    "ts",
    "tsx",
    "js",
    "jsx",
    "json",
    "node"
  ]
}
```
jest ts: https://github.com/kulshekhar/ts-jest