Jest: Confusing "No tests found" message when using testPathIgnorePatterns

[qwertie]

🐛 Bug Report

As noted in issue #1047, Jest ignores all tests if testPathIgnorePatterns matches the path to the repo. This seems like a bug but the Jest devs seem to treat this behavior as intentional, so I am just here to complain that there seems to be a bug in the way Jest reports what it is doing to users. In particular, it tells users that testPathIgnorePatterns has 0 matches.

To Reproduce

• Make a project whose test file will be "accidentally" ignored:

  mkdir ignored
  cd ignored
  npm init -f
  echo test('',function(){}) > my.test.js

• In package.json, add an ignore pattern matching a parent folder:

  "jest": {
  "testPathIgnorePatterns": ["ignore.*"]
  }

• Run jest and observe unhelpful error message:

  No tests found
  In C:\Dev\ignored
  2 files checked.
  testMatch: /__tests__//.js?(x),/?(.)+(spec|test).js?(x) - 1 match
  testPathIgnorePatterns: ignore.* - 0 matches
  Pattern: - 0 matches

jest --version: 23.4.0

Expected behavior

The message should be clear that testPathIgnorePatterns is causing files to be ignored. Also I suggest mentioning either that testPathIgnorePatterns can match the parent folder and/or that <rootDir> can avoid that problem. Also, why does Jest print Pattern: - 0 matches? That's not meaningful.

Suggested output:

No tests found
In C:\Dev\ignored
  2 files checked.
  testMatch: **/__tests__/**/*.js?(x),**/?(*.)+(spec|test).js?(x) - 1 match
  testPathIgnorePatterns: ignore.* - 1 ignored
Caution: testPathIgnorePatterns does not begin with <rootDir> so
  it is potentially matched against the name of a parent directory.

[ashnur]

also would be nice to know how to use this option from CLI, because there any kind of value basically just makes everything to be ignored all the time...

[Kamilius]

Any progress on this one? Seems like it's not possible to use testPathIgnorePatterns from CLI, as it basically continues to ignore everything

[TomasBarry]

@qwertie, @ashnur, @Kamilius

I've managed to get testPathIgnorePatterns on the CLI.

The docs are not clear on how to use testPathIgnorePatterns in the CLI however the following will work:

jest --testPathIgnorePatterns=\"pattern\"

For example, if I used a .unit.spec.js and .integration.spec.js suffix on my tests to differentiate between integration and unit tests I could run the following:

# Test only the .unit.spec.js tests (or all tests that don't have .integration.spec.js in the file name)
"jest --testPathIgnorePatterns=\".*.integration.spec.js*\""

# Test only the .integration.spec.js tests (or all tests that don't have .unit.spec.js in the file name)
"jest --testPathIgnorePatterns=\".*.unit.spec.js*\""

And if you want to add this to your package.json then it would look like:

...
"scripts": {
    "test": "jest",
    "test:unit": "jest --testPathIgnorePatterns=\".*.integration.spec.js.*\"",
    "test:integration": "jest --testPathIgnorePatterns=\".*.unit.spec.js.*\"",
}
...

Or you could use:

"scripts": {
    "test": "jest",
    "test:unit": "jest \".*.unit.spec.js\"",
    "test:integration": "jest \".*.integration.spec.js\""
}

In short, jest --testPathIgnorePatterns=\".pattern\" works for the Jest CLI.

Note that I am using Jest 23.6.0 that does not document testPathIgnorePatterns but it is present.