Bug: v8 RuleTester crashes on ESLint >=9.5.0 #9676
Description
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Relevant Package
rule-tester
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Description
When I set up a very standard usage of @typescript-eslint/rule-tester@8.0.0-alpha.59 with eslint@9.5.0 in Vitest, test runs crash with:
FAIL src/no-loop-over-enum.test.ts > no-loop-over-enum > invalid >
enum Values { value }
for (const a in Values) {}
TypeError: Cannot read properties of undefined (reading 'parse')
❯ parse node_modules/eslint/lib/linter/linter.js:906:29
❯ Linter._verifyWithFlatConfigArrayAndWithoutProcessors node_modules/eslint/lib/linter/linter.js:1660:33
❯ Linter._verifyWithFlatConfigArray node_modules/eslint/lib/linter/linter.js:2017:21
❯ Linter.verify node_modules/eslint/lib/linter/linter.js:1492:61
❯ RuleTester.runRuleForItem node_modules/@typescript-eslint/rule-tester/src/RuleTester.ts:710:33
❯ RuleTester.#testInvalidTemplate node_modules/@typescript-eslint/rule-tester/src/RuleTester.ts:862:25
❯ node_modules/@typescript-eslint/rule-tester/src/RuleTester.ts:513:40
This does not reproduce with eslint@9.4.0.
Full repro on: https://github.com/JoshuaKGoldberg/repros/tree/repro-rule-tester-eslint-parse-error
Additional Info
No response