npm test with locale de_DE.UTF-8 fails 2 tests

[Everything2067]

This happens on 10.1.0. Running

npm ci
npm run build

work fine, but running LANG=de_DE.UTF-8 npm test fails two tests. Thought this may be of interest ---

  1) program.Program
       reports unknown commands:
     YError: Unbekanntes Argument: thing
      at Object.fail (file:///home/user/.tmp/web-ext/node_modules/yargs/build/lib/usage.js:61:26)
      at Object.unknownArguments (file:///home/user/.tmp/web-ext/node_modules/yargs/build/lib/validation.js:109:19)
      at file:///home/user/.tmp/web-ext/node_modules/yargs/build/lib/yargs-factory.js:1486:78
      at file:///home/user/.tmp/web-ext/node_modules/yargs/build/lib/yargs-factory.js:1191:13
      at maybeAsyncResult (file:///home/user/.tmp/web-ext/node_modules/yargs/build/lib/utils/maybe-async-result.js:9:15)
      at YargsInstance.[validateAsync] (file:///home/user/.tmp/web-ext/node_modules/yargs/build/lib/yargs-factory.js:1190:16)
      at YargsInstance.[runYargsParserAndExecuteCommands] (file:///home/user/.tmp/web-ext/node_modules/yargs/build/lib/yargs-factory.js:1457:55)
      at YargsInstance.parse (file:///home/user/.tmp/web-ext/node_modules/yargs/build/lib/yargs-factory.js:707:63)
      at YargsInstance.get [as argv] (file:///home/user/.tmp/web-ext/node_modules/yargs/build/lib/yargs-factory.js:31:30)
      at Program.getArguments (file:///home/user/.tmp/web-ext/src/program.js:160:25)
      at Program.execute (file:///home/user/.tmp/web-ext/src/program.js:254:23)
      at execProgram (file:///home/user/.tmp/web-ext/tests/unit/test.program.js:25:20)
      at Context.<anonymous> (file:///home/user/.tmp/web-ext/tests/unit/test.program.js:42:12)
      at processImmediate (node:internal/timers:504:21)

  2) program.Program
       throws an error about unknown commands:
     AssertionError: expected 'Unbekanntes Argument: nope' to match /Unknown argument: nope/
      at file:///home/user/.tmp/web-ext/tests/unit/test.program.js:213:14
      at processTicksAndRejections (node:internal/process/task_queues:104:5)

I have attached the entire output.
test.log

Running the entire build process with the same locale results the same.
I have only tested de_DE.UTF-8 (which results in 2 failed tests) and en_GB.UTF-8 (which works perfectly fine).
Please let me know if you need more information.

[Rob--W]

The unit test verify the output, but the underlying library may localize the string.

This can be fixed by forcing LANG=en_US.UTF-8 environment variable in test.program.js (or run the whole test with this set).