开玩笑：无法读取 testEnvironmentOptions

Question

我在使用 Jest 时遇到以下错误，但不清楚为什么即使在添加了 testEnvironmentOptions 之后

       TypeError: Cannot read properties of undefined (reading 'testEnvironmentOptions')
    
          at new JSDOMEnvironment (node_modules/jest-environment-jsdom/build/index.js:72:28)
          at async TestScheduler.scheduleTests (node_modules/@jest/core/build/TestScheduler.js:333:13)
          at async runJest (node_modules/@jest/core/build/runJest.js:404:19)

这是我在package.json 中的 Jest 配置：

    "jest": {
        "moduleNameMapper": {
          "^@/(.*)$": "<rootDir>/$1",
          "^~/(.*)$": "<rootDir>/$1",
          "^vue$": "vue/dist/vue.common.js"
        },
        "testEnvironment": "jsdom",
        "testEnvironmentOptions": {
          "browsers": [
            "chrome",
            "firefox",
            "safari"
          ]
        },
        "moduleFileExtensions": [
          "vue",
          "js",
          "json"
        ],
        "transformIgnorePatterns": [
          "/node_modules/(?!crypto-random-string)"
        ],
        "transform": {
          "^.+\\.js$": "<rootDir>/node_modules/babel-jest",
          ".*\\.(vue)$": "<rootDir>/node_modules/vue-jest"
        },
        "collectCoverage": true,
        "collectCoverageFrom": [
          "<rootDir>/src/**/*.vue",
          "<rootDir>/src/**/*.js"
        ]
      }

Answer 1

确保您在同一版本中安装了两个软件包 jest 和 jest-environment-jsdom。后者需要与jest 28 版分开安装。我在将jest 降级到 27.x 而不是jest-environment-jsdom 时遇到了同样的问题。看看version 27 to 28 upgrade guide about using JSDOM test environment。