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mocha -r esm: ERR_VM_DYNAMIC_IMPORT_CALLBACK_MISSING

See original GitHub issue

Prerequisites

Checked that your issue hasn’t already been filed by cross-referencing issues with the faq label
Checked next-gen ES issues and syntax problems by using the same environment and/or transpiler configuration without Mocha to ensure it isn’t just a feature that actually isn’t supported in the environment in question or a bug in your code.
‘Smoke tested’ the code to be tested by running it outside the real test suite to get a better sense of whether the problem is in the code under test, your usage of Mocha, or Mocha itself
Ensured that there is no discrepancy between the locally and globally installed versions of Mocha. You can find them with: node node_modules/.bin/mocha --version(Local) and mocha --version(Global). We recommend that you not install Mocha globally.

Description

Since version v9.0.0 mocha crashes when I try to use it with ESM.

Steps to Reproduce

Expected behavior: [What you expect to happen] Mocha should run successfully.

Actual behavior: [What actually happens]

Mocha crashes.

Stack trace:

TypeError [ERR_VM_DYNAMIC_IMPORT_CALLBACK_MISSING]: A dynamic import callback was not specified.
    at new NodeError (node:internal/errors:363:5)
    at exports.importModuleDynamicallyCallback (node:internal/process/esm_loader:34:9)
    at formattedImport (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/mocha/lib/esm-utils.js:7:31)
    at Object.exports.requireOrImport (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/mocha/lib/esm-utils.js:48:38)
    at Object.exports.loadFilesAsync (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/mocha/lib/esm-utils.js:73:34)
    at Mocha.loadFilesAsync (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/mocha/lib/mocha.js:467:19)
    at singleRun (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/mocha/lib/cli/run-helpers.js:125:15)
    at exports.runMocha (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/mocha/lib/cli/run-helpers.js:190:10)
    at Object.exports.handler (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/mocha/lib/cli/run.js:366:11)
    at /Users/yonom/GitHub/test/mocha-bug-report/node_modules/yargs/build/index.cjs:443:71
    at process.runNextTicks [as _tickCallback] (node:internal/process/task_queues:61:5)
    at /Users/yonom/GitHub/test/mocha-bug-report/node_modules/esm/esm.js:1:34535
    at /Users/yonom/GitHub/test/mocha-bug-report/node_modules/esm/esm.js:1:34176
    at process.<anonymous> (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/esm/esm.js:1:34506)
    at Function.<anonymous> (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/esm/esm.js:1:296856)
    at Function.<anonymous> (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/esm/esm.js:1:296555)
    at Function.<anonymous> (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/esm/esm.js:1:284879)
    at Object.apply (/Users/yonom/GitHub/test/mocha-bug-report/node_modules/esm/esm.js:1:199341)
    at node:internal/main/run_main_module:17:47

Reproduces how often: [What percentage of the time does it reproduce?]

100% (always)

Versions

The output of mocha --version and node node_modules/.bin/mocha --version: 9.0.1
The output of node --version: v16.4.0 (also tested on v14.17.1)
Your operating system
- name and version: macOS 11.4 (also tested on GitHub Actions Ubuntu 20.04)
- architecture (32 or 64-bit): 64-bit
Your shell (e.g., bash, zsh, PowerShell, cmd): zsh (also tested on bash)
Your browser and version (if running browser tests): N/A
Any third-party Mocha-related modules (and their versions): N/A
Any code transpiler (e.g., TypeScript, CoffeeScript, Babel) being used (and its version): ESM v3.2.25

Additional Information

Repository for reproduction: https://github.com/Yonom/mocha-bug-report

You can run yarn test in the (mostly empty) repo abobe to see the error occur. No actual tests are needed, an empty test file suffices to trigger the issue (but the error still happens even with real tests existing of course).

Issue Analytics

State:
Created 2 years ago
Comments:10 (8 by maintainers)

Top GitHub Comments

2reactions

giltayarcommented, Jul 1, 2021

OK, I tried. I added the code above, but while trying to write a test that used the esm package, I got all sorts of weird unexplainable behaviors. I could spend a few days figuring things out and maybe getting it to work, but as @juergba said, it’s not worth it for a package that hasn’t been maintained for 2 years.

So, sorry @Yonom, but it seems you’ll have to stick to Mocha v8 till you ugprade to native Node.js ESM, or submit a PR (with a test) yourself.

1reaction

juergbacommented, Jul 1, 2021

ok, thank you @giltayar @Yonom can I close?

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