Even though --files is no longer supported, you can use an env variable to provide a list of files:
// karma.conf.js
function getSpecs(specList) {
if (specList) {
return specList.split(',')
} else {
return ['**/*_spec.js'] // whatever your default glob is
}
}
module.exports = function(config) {
config.set({
//...
files: ['app.js'].concat(getSpecs(process.env.KARMA_SPECS))
});
});
Then in CLI:
$ env KARMA_SPECS="spec1.js,spec2.js" karma start karma.conf.js --single-run