Because ESM not really there yet.
Result of a quick research on how to get ESM code to test in Node.js with accurate code coverage reports.
Uses:
Includes:
- Eslint + Prettier config
- VSCode launcher
npm ci
npm run test
npm run coverage
Placing a breakpoint in VSCode does not work all the time. There seems to be an off by one problem, displacing the breakpoint when you execute the tests.
Workaround: debugger works 100%. You will have to temporarily disable eslint/prettier auto fix, as the debugger;
statement is automatically removed on save.
Attempting to use all: true
in .nycrc
causes it to crash with Cannot convert undefined or null to object
. Possibly related with this issue: --all is super broken.
Workaround: adding a placeholder test for each file will report the file.
-
the
--require esm
argument, when running_mocha
-
the
"require": ["esm"]
setting, in.nycrc
"require": [
"esm"
],
- the
cjs: true
setting, in package.json
"esm": {
"cjs": true
},
Kudos:
- all the people trying hard out there
- John-David Dalton's ESM package
- ESM Zero Configuration
- dschnare/std-esm-sandbox - older boilderplate that was still using the deprecated
@std/esm
- Native ES Modules in NodeJS: Status And Future Directions - good read
- Testing in ES6 with Mocha and Babel 6 - another good read, even if Babel is no longer required here
Copyright (c) 2017 Andre Torgal
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