Meteor 3.3.x and meteortesting:mocha/lmieulet:meteor-coverage

help
1

Hi,

I have issue using meteortesting:mocha/lmieulet:meteor-coverage whith meteor@3.3.x when modern: true

With modern: false, it works well but with modern: true, i have the following error (all tests passed but the coverage not):

W20250909-10:14:44.909(2)? (STDERR) Error: Failed to save lcovonly coverage. 500 [object Object]
W20250909-10:14:44.910(2)? (STDERR)     at packages/meteortesting:mocha/server.handleCoverage.js:21:11
W20250909-10:14:44.910(2)? (STDERR)     at Generator.next (<anonymous>)
W20250909-10:14:44.910(2)? (STDERR)     at asyncGeneratorStep (/tmp/meteor-test-run1j4ree.uzqzq/.meteor/local/build/programs/server/packages/meteortesting_mocha.js:280:28)
W20250909-10:14:44.910(2)? (STDERR)     at _next (/tmp/meteor-test-run1j4ree.uzqzq/.meteor/local/build/programs/server/packages/meteortesting_mocha.js:298:17)
W20250909-10:14:44.910(2)? (STDERR)     at processTicksAndRejections (node:internal/process/task_queues:105:5)

The command line is the following :

MONGO_URL='' BABEL_ENV=test TEST_CLIENT=0 NO_HMR=1 COVERAGE=1 COVERAGE_OUT_LCOVONLY=1 COVERAGE_APP_FOLDER=$PWD/ meteor test --once --driver-package meteortesting:mocha

Thanks.

2

I’d appreciate it if you could prepare a minimal repo for this. Matching your config is tricky. Having one would save a lot of time so I can focus on the fix.

For SWC, we may need to use it with kwonoj/swc-plugin-coverage-instrument. Having an example repository will allow me to play with it and provide a skeleton for everyone.

3

Thanks. Here a minimal repo :

meteor run then meteor npm run test and you get the error.