Only in coverage mode, latest babel: 'import' and 'export' may appear only with 'sourceType: "module"'

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

Bug

What is the current behavior?

Since updating to Babel 7.0-beta.46, Jest fails only when using --coverage with this error:

ERROR: 'import' and 'export' may appear only with 'sourceType: "module"' (8:0)
STACK: SyntaxError: 'import' and 'export' may appear only with 'sourceType: "module"' (1:0)
    at Parser.pp$5.raise (/Users/fakepath/node_modules/babylon/lib/index.js:4454:13)
    at Parser.pp$1.parseStatement (/Users/fakepath/node_modules/babylon/lib/index.js:1881:16)
    at Parser.parseStatement (/Users/fakepath/node_modules/babylon/lib/index.js:5910:22)
    at Parser.pp$1.parseBlockBody (/Users/fakepath/node_modules/babylon/lib/index.js:2268:21)
    at Parser.pp$1.parseTopLevel (/Users/fakepath/node_modules/babylon/lib/index.js:1778:8)
    at Parser.parse (/Users/adrien/fakepath/node_modules/babylon/lib/index.js:1673:17)
    at Object.parse (/Users/fakepath/node_modules/babylon/lib/index.js:7305:37)
    at Instrumenter.instrumentSync (/Users/fakepath/node_modules/istanbul-lib-instrument/dist/instrumenter.js:123:31)
    at exports.default (/Users/fakepath/node_modules/jest-cli/build/generate_empty_coverage.js:18:18)
    at Object.worker (/Users/fakepath/node_modules/jest-cli/build/reporters/coverage_worker.js:48:84)
Failed to collect coverage from /Users/fakepath/src/utils/Utils.js

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.

Couldn’t manage to reproduce it in a minimal environment (yet). Still working on it.

What is the expected behavior?

Jest should work the same with or without --coverage

Please provide your exact Jest configuration

const path = require('path');

const configBase = {
  collectCoverageFrom: ['**/utils/*.js', '!**/lib/utils/**'],
  coverageDirectory: path.join(__dirname, '../../coverage'),
  moduleNameMapper: {
    '\\.(css|scss)$': 'identity-obj-proxy',
    '\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$': path.join(
      __dirname,
      'node_modules/shared/__mocks__/fileMock.js',
    ),
  },
  moduleDirectories: ['../../node_modules', 'node_modules'],
  modulePaths: [path.join(__dirname, 'client')],
  rootDir: __dirname,
  roots: [__dirname],
  testRegex: '\\.test\\.js$',
};

const configJUnit = process.env.JEST_JUNIT_OUTPUT
  ? {
      testResultsProcessor: 'jest-junit',
    }
  : {};

module.exports = Object.assign({}, configBase, configJUnit);

Run npx envinfo --preset jest in your project directory and paste the results here

  System:
    OS: macOS High Sierra 10.13.4
    CPU: x64 Intel(R) Core(TM) i7-7567U CPU @ 3.50GHz
  Binaries:
    Node: 8.11.1 - /usr/local/bin/node
    Yarn: 1.5.1 - /usr/local/bin/yarn
    npm: 5.6.0 - /usr/local/bin/npm

[loganfsmyth]

Babel beta.45/beta.46 introduces a breaking change that will primarily affect monorepo users, and people compiling node_modules files. .babelrc searching now

• Stops at the first package.json it finds relative to the file being compiled, so things in sub-packages will not find a root-level .babelrc
• Only searches if the file being compiled is inside of the “root” package, which means it will skip searching for .babelrc files entirely for sub-packages in a repo

In most monorepos, that means that a config at the root will be ignored, and configs in sub-packages will also.

To have a config at the root of your monorepo, you should name the file babel.config.js, which is a new non-hierarchical config file that loads from the root directory. If you want to keep per-package configs, instead you’ll want to enable configs in packages/*/.babelrc to work in a monorepo by passing Babel

babelrcRoots: "packages/*"

in the programmatic options.

For people compiling node_modules this is also a change, because a .babelrc in one package will not affect that package’s node_modules. You’ll also want to rename your project-root .babelrc to a babel.config.js file exporting the config, to do that.

If your config doesn’t fall into one of those changes, then there could always still be a bug somewhere.

[shorif2000]

is there an example repo?