eslint config requires "requireConfigFile: false"

[hueniverse]

Runtime

node.js

Runtime version

22.12.0

Module version

26.0.0

Used with

No response

Any other relevant information

After upgrading to eslint 9 and lab 26, coverage failed with:

Cannot read properties of undefined (reading 'includes')
TypeError: Cannot read properties of undefined (reading 'includes')
    at validateResolvedConfig (/project/node_modules/@babel/eslint-parser/lib/worker/configuration.cjs:53:37)
    at Object.normalizeBabelParseConfigSync (/project/node_modules/@babel/eslint-parser/lib/worker/configuration.cjs:88:10)
    at Function.handleMessage (/project/node_modules/@babel/eslint-parser/lib/worker/handle-message.cjs:26:48)
    at LocalClient.<anonymous> (/project/node_modules/@babel/eslint-parser/lib/client.cjs:98:79)
    at LocalClient.maybeParse (/project/node_modules/@babel/eslint-parser/lib/client.cjs:52:47)
    at parse (/project/node_modules/@babel/eslint-parser/lib/parse.cjs:28:14)
    at Object.parse (/project/node_modules/@babel/eslint-parser/lib/index.cjs:19:10)
    at Object.internals.instrument (/project/node_modules/@hapi/lab/lib/modules/coverage.js:326:31)
    at Object.require.extensions.<computed> [as .ts] (/project/node_modules/@hapi/lab/lib/modules/coverage.js:116:59)

Which is resolved by adding requireConfigFile to the eslint config:

    languageOptions: {
      parser: tseslint.parser,
      parserOptions: { requireConfigFile: false },
    },

I am using eslint.config.mjs in case that matters.

Was this expected? Is there a better solution? Should this be added to lab itself?

Thanks!