Performance degrades the more wildcards that are contained in TSConfig include or exclude patterns

🔎 Search Terms

wildcard pattern include exclude tsconfig regex regexp regular expression glob performance slow node

🕗 Version & Regression Information

• This is the behavior in every version I tried

⏯ Playground Link

No response

💻 Code

Create a TS project with any empty TS file and the following TSConfig.

{
  "compilerOptions": {
    "noCheck": true,
    "noEmit": true,
    "noResolve": true,
  },
  "exclude": [
    "alpha/beta/gamma/delta/epsilon/zeta/eta/theta/iota/kappa/lambda/**/*.ts",
    "alpha/beta/gamma/delta/epsilon/zeta/eta/theta/iota/kappa/lambda/**/*.ts",
    "alpha/beta/gamma/delta/epsilon/zeta/eta/theta/iota/kappa/lambda/**/*.ts",
    ...repeat a couple hundred or more times
  ]
}

I've created a repo to more easily reproduce the behavior: https://github.com/MichaelMitchell-at/typescript_slow_wildcards_repro

🙁 Actual behavior

tsc takes several seconds to run on the project, even though there is no work to do and there are no files to compare the exclude patterns against. In fact, running tsc with node --jitless is much faster than without.

🙂 Expected behavior

tsc should complete quickly.

Additional information about the issue

I've determined through profiling that the issue is that a giant RegExp combining all the patterns gets created which is very slow to evaluate.
https://github.com/microsoft/TypeScript/blob/739d729ecce60771c23723aad932ab35a34df82d/src/compiler/utilities.ts#L9556-L9566

From my testing, it's much faster to build a separate RegExp for each pattern and test them one by one for large number of patterns and for a small number of patterns there is no perceivable difference in speed. I've created a PR implementing this change which greatly improves the performance: https://github.com/microsoft/TypeScript/pull/61104

Inizia in src/compiler/utilities.ts alle righe 9556-9566, quindi esegui il progetto collegato typescript_slow_wildcards_repro con i pattern exclude ripetuti di tsconfig. Confronta il tempo di esecuzione del compilatore per insiemi di pattern grandi e piccoli e considera il PR 61104 esistente quando verifichi il miglioramento delle prestazioni previsto.