<rootDir> is not respected by collectCoverageFrom

[StephanBijzitter]

Do you want to request a feature or report a bug?
I want to report a bug.

What is the current behavior?
When using <rootDir>/foo/bar as a value for collectCoverageFrom, no coverage is being collected at all.

However, using foo/bar does work as expected.

If the current behavior is a bug, please provide the steps to reproduce and
either a repl.it demo through https://repl.it/languages/jest or a minimal
repository on GitHub that we can yarn install and yarn test.

Take your own config and edit (or add) your collectCoverageFrom field with a value that starts with <rootDir>; then run jest with coverage enabled (yarn jest --coverage).

What is the expected behavior?
Coverage results are the same for both <rootDir>/foo/bar and foo/bar (where cwd is the root dir).

Please provide your exact Jest configuration and mention your Jest, node,
yarn/npm version and operating system.
Yarn 1.3.2, Jest 22.2.1, ts-jest 22.0.3, Node 8.9.1.

Jest config:

  {
    "automock": false,
    "resetModules": true,
    "collectCoverage": false,
    "coverageDirectory": "<rootDir>/coverage/jest",
    "collectCoverageFrom": [
      "<rootDir>/packages/*/src/**/*.js",
      "<rootDir>/packages/*/src/**/*.ts",
      "!<rootDir>/packages/*/src/**/index.*",
      "!<rootDir>/packages/*/src/**/*.spec.*",
      "!<rootDir>/packages/*/src/**/*.snapshot.*"
    ],
    "testMatch": [
      "<rootDir>/packages/*/src/**/*.spec.js",
      "<rootDir>/packages/*/src/**/*.spec.ts"
    ],
    "moduleFileExtensions": [
      "js",
      "ts",
      "json"
    ],
    "transform": {
      "^.+\\.ts$": "ts-jest"
    }
  }

[SimenB]

This is expected, as the docs point out it's relative to rootDir in the first place. I agree it's confusing though, PR welcome to at least strip out <rootDir>/ if it's provided.

https://github.com/facebook/jest/blob/f29c03ea0c97d97aede05b5c1a97ce04a953d3f9/packages/jest-cli/src/cli/args.js#L154-L159

[StephanBijzitter]

Ah, yeah it would be nice for consistency if rootDir can be used, even if it means ignoring it. Will take a look, this sounds like a nice first contribution!

Edit: after searching through the repository I guess this would be the place to strip out any rootDir usage: https://github.com/facebook/jest/blob/1947496728db13a4f271dfef8e9b9cecdcb9ee40/packages/jest-config/src/normalize.js#L130-L164

Seems easy enough at first sight :-)

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.
Please note this issue tracker is not a help forum. We recommend using StackOverflow or our discord channel for questions.