Source map files disappear from coverage report

Hi,

I’m getting coverage issues with Jest. When I set mapCoverage: true, some files disapear from the coverage report.

Example:

# mapCoverage:true
src/api                |      100 |      100 |      100 |      100 |                |
  index.js             |      100 |      100 |      100 |      100 |                |
  linkHeaderParser.js  |      100 |      100 |      100 |      100 |                |
  repositories.js      |      100 |      100 |      100 |      100 |                |
src/components         |     7.84 |     2.94 |     5.88 |    11.76 |                |
  FileExplorer.vue     |        0 |        0 |        0 |        0 |... 51,52,53,54 |
  MenuUserRepoList.vue |        0 |        0 |        0 |        0 |... 32,33,34,35 |
  Profile.vue          |        0 |        0 |        0 |        0 |... 57,58,59,60 |
  Readme.vue           |       80 |       50 |       50 |       80 |             23 |

# mapCoverage:false
src/api                |    92.86 |    84.21 |      100 |    92.86 |                |
  index.js             |    84.62 |    66.67 |      100 |    84.62 |          10,26 |
  linkHeaderParser.js  |      100 |      100 |      100 |      100 |                |
  repositories.js      |      100 |      100 |      100 |      100 |                |
  users.js             |      100 |      100 |      100 |      100 |                |
src/components         |     53.4 |    29.73 |    40.74 |    51.61 |                |
  FileExplorer.vue     |        0 |        0 |        0 |        0 |... 51,52,53,54 |
  FooterBar.vue        |    92.86 |       50 |      100 |      100 |        4,5,6,7 |
  MenuNavBar.vue       |      100 |       50 |      100 |      100 |       20,21,22 |
  MenuUserRepoList.vue |        0 |        0 |        0 |        0 |... 32,33,34,35 |
  Profile.vue          |        0 |        0 |        0 |        0 |... 57,58,59,60 |
  Readme.vue           |    94.74 |    57.14 |       80 |    92.86 |             25 |
  RepoListItem.vue     |      100 |       50 |    66.67 |      100 |       45,46,47 |

(I remove some file for a better readability. See full coverage report (link to travis build):

All sources files are available here: https://github.com/maxpou/gitvub and jest config here

Thank you

[nirkki]

Looks like the missing files lack the data property. If the component doesn’t have the data segment it is dropped from the coverage report. Adding an empty segment is enough to get it included.

export default {
  name: 'HelloWorld',
  props: {
    msg: { type: String, default: 'Welcome to Your Vue.js App' }
  },
  data () {
    return {}
  }
}

[kaidjohnson]

I have been dealing with this issue setting up a new project. It can be reproduced using the latest vue-cli (3.0.5) and following the “Creating a Project” guide (https://cli.vuejs.org/guide/creating-a-project.html#vue-create).

vue create hello-world
> Manually select features
(x) Babel
(x) Unit Testing
> Jest
> In dedicated config files

Edit jest.config.js and add:

  collectCoverage: true,
  collectCoverageFrom: ['src/**/*.{js,vue}'],
  coverageReporters: ['text'],

Run npm run test:unit

Notice that HelloWorld.vue is missing from the test report.

Edit components/HelloWorld.vue and add in an empty data segment

data() {
  return {};
}

Run npm run test:unit again

Notice that HelloWorld.vue suddenly appears with its test coverage.

Thanks @nirkki for the workaround!! I have been parsing bug reports all evening with no luck as to what was causing this missing coverage.

The package.json that results from the vue-cli build:

{
  "name": "hello-world",
  "version": "0.1.0",
  "private": true,
  "scripts": {
    "serve": "vue-cli-service serve",
    "build": "vue-cli-service build",
    "test:unit": "vue-cli-service test:unit"
  },
  "dependencies": {
    "vue": "^2.5.17"
  },
  "devDependencies": {
    "@vue/cli-plugin-babel": "^3.0.5",
    "@vue/cli-plugin-unit-jest": "^3.0.5",
    "@vue/cli-service": "^3.0.5",
    "@vue/test-utils": "^1.0.0-beta.20",
    "babel-core": "7.0.0-bridge.0",
    "babel-jest": "^23.0.1",
    "vue-template-compiler": "^2.5.17"
  }
}

It’s not a vue-cli issue, either, as I originally ran across the bug with a manual setup. In that scenario, the empty data segment also fixed the issue. That package json looks like:

{
  "name": "new-project",
  "version": "0.0.1",
  "description": "",
  "scripts": {
    "build": "webpack",
    "dev": "webpack-dev-server",
    "lint": "eslint 'src/**/*.{js,vue}'",
    "test": "jest",
    "tdd": "jest --watchAll"
  },
  "devDependencies": {
    "@babel/core": "7.1.2",
    "@babel/plugin-syntax-dynamic-import": "7.0.0",
    "@babel/preset-env": "7.1.0",
    "@vue/test-utils": "1.0.0-beta.25",
    "babel-core": "7.0.0-bridge.0",
    "babel-eslint": "10.0.1",
    "babel-jest": "23.6.0",
    "babel-loader": "8.0.4",
    "clean-webpack-plugin": "0.1.19",
    "eslint": "5.7.0",
    "eslint-plugin-jest": "21.26.1",
    "eslint-plugin-vue": "4.7.1",
    "html-webpack-plugin": "3.2.0",
    "jest": "23.6.0",
    "redux": "4.0.1",
    "reselect": "4.0.0",
    "vue": "2.5.17",
    "vue-cli": "2.9.6",
    "vue-jest": "3.0.0",
    "vue-loader": "15.4.2",
    "vue-router": "3.0.1",
    "vue-template-compiler": "2.5.17",
    "webpack": "4.22.0",
    "webpack-cli": "3.1.2",
    "webpack-dev-server": "3.1.10"
  }
}