🐛 Bug: mocha 10.2.0 prints out command help text and ERROR: null with ts-node and experimental-specifier-resolution

[khteh]

Bug Report Checklist

• I have read and agree to Mocha's Code of Conduct and Contributing Guidelines
• I have searched for related issues and issues with the faq label, but none matched my issue.
• I have '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, my usage of Mocha, or Mocha itself.
• I want to provide a PR to resolve this

Expected

Successfully run tests with mocha 10.2.0

Actual

$ ./node_modules/.bin/mocha -r ts-node/register tests/**/*.ts --reporter mocha-junit-reporter --reporter-options mochaFile=test_reports/mocha/test-results.xml --exit
(node:75854) ExperimentalWarning: `--experimental-loader` may be removed in the future; instead use `register()`:
--import 'data:text/javascript,import { register } from "node:module"; import { pathToFileURL } from "node:url"; register("ts-node/esm", pathToFileURL("./"));'
(Use `node --trace-warnings ...` to show where the warning was created)
mocha inspect [spec..]

Run tests with Mocha

Rules & Behavior
      --allow-uncaught       Allow uncaught errors to propagate        [boolean]
  -A, --async-only           Require all tests to use a callback (async) or
                             return a Promise                          [boolean]
  -b, --bail                 Abort ("bail") after first test failure   [boolean]
      --check-leaks          Check for global variable leaks           [boolean]
      --delay                Delay initial execution of root suite     [boolean]
      --dry-run              Report tests without executing them       [boolean]
      --exit                 Force Mocha to quit after tests complete  [boolean]
      --fail-zero            Fail test run if no test(s) encountered   [boolean]
      --forbid-only          Fail if exclusive test(s) encountered     [boolean]
      --forbid-pending       Fail if pending test(s) encountered       [boolean]
      --global, --globals    List of allowed global variables            [array]
  -j, --jobs                 Number of concurrent jobs for --parallel; use 1 to
                             run in serial
                                   [number] [default: (number of CPU cores - 1)]
  -p, --parallel             Run tests in parallel                     [boolean]
      --retries              Retry failed tests this many times         [number]
  -s, --slow                 Specify "slow" test threshold (in milliseconds)
                                                          [string] [default: 75]
  -t, --timeout, --timeouts  Specify test timeout threshold (in milliseconds)
                                                        [string] [default: 2000]
  -u, --ui                   Specify user interface    [string] [default: "bdd"]

Reporting & Output
  -c, --color, --colors                     Force-enable color output  [boolean]
      --diff                                Show diff on failure
                                                       [boolean] [default: true]
      --full-trace                          Display full stack traces  [boolean]
      --inline-diffs                        Display actual/expected differences
                                            inline within each string  [boolean]
  -R, --reporter                            Specify reporter to use
                                                      [string] [default: "spec"]
  -O, --reporter-option,                    Reporter-specific options
  --reporter-options                        (<k=v,[k1=v1,..]>)           [array]

Configuration
      --config       Path to config file   [string] [default: (nearest rc file)]
  -n, --node-option  Node or V8 option (no leading "--")                 [array]
      --package      Path to package.json for config                    [string]

File Handling
      --extension          File extension(s) to load
                                           [array] [default: ["js","cjs","mjs"]]
      --file               Specify file(s) to be loaded prior to root suite
                           execution                   [array] [default: (none)]
      --ignore, --exclude  Ignore file(s) or glob pattern(s)
                                                       [array] [default: (none)]
      --recursive          Look for tests in subdirectories            [boolean]
  -r, --require            Require module              [array] [default: (none)]
  -S, --sort               Sort test files                             [boolean]
  -w, --watch              Watch files in the current working directory for
                           changes                                     [boolean]
      --watch-files        List of paths or globs to watch               [array]
      --watch-ignore       List of paths or globs to exclude from watching
                                      [array] [default: ["node_modules",".git"]]

Test Filters
  -f, --fgrep   Only run tests containing this string                   [string]
  -g, --grep    Only run tests matching this string or regexp           [string]
  -i, --invert  Inverts --grep and --fgrep matches                     [boolean]

Positional Arguments
  spec  One or more files, directories, or globs to test
                                                     [array] [default: ["test"]]

Other Options
  -h, --help             Show usage information & exit                 [boolean]
  -V, --version          Show version number & exit                    [boolean]
      --list-interfaces  List built-in user interfaces & exit          [boolean]
      --list-reporters   List built-in reporters & exit                [boolean]

✖ ERROR: null

In fact, just executing ./node_modules/.bin/mocha itself without any input params will hit the same console output error.

Minimal, Reproducible Example

https://github.com/khteh/Node.JSRestAPI

Versions

10.2.0
v21.5.0

Additional Info

No response

[jwalton]

I ran into this problem too. I solved it by downgrading to node 18.16.1 (not sure exactly which node version you need, but node 18.19.0 is too recent), then running mocha, then I got an actual real error message. I fixed the problem, upgraded back to node 20, and all was well.

In my particular case, the problem was in my tsconfig.json file. With:

  "compilerOptions": {
    "module": "NodeNext",
    "moduleResolution": "NodeNext",
    ...

things would fail, where with:

  "compilerOptions": {
    "module": "ESNext",
    "moduleResolution": "node",
    ...

everything was fine.

[JoshuaKGoldberg]

Spooky. I played around a bit and couldn't figure out if this is a dup of #5085 or a separate root cause that happens to be throwing a null error.

[stalet]

Spooky. I played around a bit and couldn't figure out if this is a dup of #5085 or a separate root cause that happens to be throwing a null error.

It looks like the same issue.