Esm: nyc generates "ReferenceError: module is not defined" in chai

[chrisveness]

In @std/esm 0.19.0 through 0.19.2, nyc generates a "ReferenceError: require is not defined" from chai/index.js:1 ( module.exports = require('./lib/chai');).

• mocha --exit -r @std/esm test/unit/*.js is fine
• nyc mocha --exit -r @std/esm test/unit/*.js with @std/esm version 0.18.0 is fine
• nyc mocha --exit -r @std/esm test/unit/*.js with @std/esm v0.19.0+ fails

Versions: @std/esm – 0.19.2, nyc – 11.4.1, chai – 4.1.2.

@std/esm options (in package.json): @std/esm: { "esm": "js" }.

Stack trace:

$ nyc mocha --exit -r @std/esm test/unit/*.js 
ReferenceError: module is not defined
    at Object.<anonymous> (file://~/app/node_modules/chai/index.js:1)
    at module.exports (file://~/app/node_modules/nyc/node_modules/default-require-extensions/js.js:8:9)
    at ~/app/node_modules/nyc/node_modules/append-transform/index.js:62:4
    at T.replacementCompile (file://~/app/node_modules/nyc/node_modules/append-transform/index.js:58:13)
    at module.exports (file://~/app/node_modules/nyc/node_modules/default-require-extensions/js.js:8:9)
    at ~/app/node_modules/nyc/node_modules/append-transform/index.js:62:4
    at Object.<anonymous> (file://~/app/node_modules/nyc/node_modules/append-transform/index.js:62:4)
    at ~/app/test/unit/auto-identifier-tests.js:1
    at Object.<anonymous> (file://~/app/test/unit/auto-identifier-tests.js:1)
    at Module._compile (module.js:635:30)
    at Module.replacementCompile (file://~/app/node_modules/nyc/node_modules/append-transform/index.js:58:13)
    at Object.<anonymous> (file://~/app/node_modules/nyc/node_modules/append-transform/index.js:62:4)
    at Module.load (module.js:554:32)
    at tryModuleLoad (module.js:497:12)
    at Function.Module._load (module.js:489:3)
    at Module.require (module.js:579:17)
    at require (internal/module.js:11:18)
    at ~/app/node_modules/mocha/lib/mocha.js:231:27
    at Array.forEach (<anonymous>)
    at Mocha.loadFiles (file://~/app/node_modules/mocha/lib/mocha.js:228:14)
    at Mocha.run (file://~/app/node_modules/mocha/lib/mocha.js:536:10)
    at Object.<anonymous> (file://~/app/node_modules/mocha/bin/_mocha:573:18)
    at Module._compile (module.js:635:30)
    at Module.replacementCompile (file://~/app/node_modules/nyc/node_modules/append-transform/index.js:58:13)
    at module.exports (file://~/app/node_modules/nyc/node_modules/default-require-extensions/js.js:8:9)
    at Object.<anonymous> (file://~/app/node_modules/nyc/node_modules/append-transform/index.js:62:4)
    at Module.load (module.js:554:32)
    at tryModuleLoad (module.js:497:12)
    at Function.Module._load (module.js:489:3)
    at Function.Module.runMain (module.js:676:10)
    at runMain (file://~/.node-spawn-wrap-4314-1f9023bc8504/node:68:10)
    at Function.<anonymous> (file://~/.node-spawn-wrap-4314-1f9023bc8504/node:171:5)
    at Object.<anonymous> (file://~/app/node_modules/nyc/bin/wrap.js:23:4)
    at Module._compile (module.js:635:30)
    at Object.Module._extensions..js (module.js:646:10)
    at Module.load (module.js:554:32)
    at tryModuleLoad (module.js:497:12)
    at Function.Module._load (module.js:489:3)
    at Function.Module.runMain (module.js:676:10)
    at ~/.node-spawn-wrap-4314-1f9023bc8504/node:178:8
    at Object.<anonymous> (file://~/.node-spawn-wrap-4314-1f9023bc8504/node:181:3)
    at Module._compile (module.js:635:30)
    at Object.Module._extensions..js (module.js:646:10)
    at Module.load (module.js:554:32)
    at tryModuleLoad (module.js:497:12)
    at Function.Module._load (module.js:489:3)
    at Function.Module.runMain (module.js:676:10)
    at startup (bootstrap_node.js:187:16)
    at bootstrap_node.js:608:3
----------|----------|----------|----------|----------|----------------|
File      |  % Stmts | % Branch |  % Funcs |  % Lines |Uncovered Lines |
----------|----------|----------|----------|----------|----------------|
All files |  Unknown |  Unknown |  Unknown |  Unknown |                |
----------|----------|----------|----------|----------|----------------|

Other tests using supertest fail with "ReferenceError: require is not defined".

[jdalton]

Thanks for the report @chrisveness!

Could you create a simple repro repo for me to check out?

[chrisveness]

I'll see what I can put together.

[jdalton]

This seems to be resolved on master.

Spoke too soon. I can repro this.

Update:

Patched https://github.com/standard-things/esm/commit/99b4b2ea4f0f461a3b9853d6fc4f26a5c4b6b073.

[jdalton]

v0.19.3 is released :tada:

[chrisveness]

That's sorted it: thanks for the fast response – fantastic!

FYI, I'm still having various problems with nyc, including generating

----------|----------|----------|----------|----------|----------------|
File      |  % Stmts | % Branch |  % Funcs |  % Lines |Uncovered Lines |
----------|----------|----------|----------|----------|----------------|
All files |  Unknown |  Unknown |  Unknown |  Unknown |                |
----------|----------|----------|----------|----------|----------------|

but it's very inconsistent behaviour, and I've no idea whether it's related to @std/esm or not. I'll see if I can put together something reproducible.