`getTypeListId` crashes with `TypeError: Cannot read properties of undefined (reading 'id')`

[wasabi315]

🔎 Search Terms

getTypeListId, circular reference, conditional types

🕗 Version & Regression Information

• This is a crash
• This changed between versions (confirmed using the Playground)
  • ~3.6.3: does not crash
  • 3.7.5 ~ 3.8.3: throws Debug Failure. False expression.
  • 3.9.7 ~ 5.6.0-dev.20240628: throws TypeError: Cannot read properties of undefined (reading 'id')
• This is the behavior in every version I tried, and I reviewed the FAQ for entries about "Circularity Errors May Occur In The Presence of Circularities"

⏯ Playground Link

https://www.typescriptlang.org/play/?#code/GYVwdgxgLglg9mABMAPAfQCoBpFoMoB8AFAJSIDeAsAFCJ2IxhQCmATsAIYTOIByIAWwCCrVhwCeKDImYAPFmAAmAZ0RhBAIzYEZ85ktUixkjDvIBfGvURRxABx4ANRAF4+goxJTO5ClRXNEAH41TTZEAC5QgS1WAgBuGktqIA

💻 Code

function f<_T, _S>() { // The number of type parameters need to be more than 2 to reproduce, strangely
    // Both have to be inside f
    interface NumArray<T extends number> extends Array<T> {}
    type X = NumArray<X extends {} ? number : number>;
}

🙁 Actual behavior

TypeScript throws the following error when type-checking the code above

      throw e;
      ^

TypeError: Cannot read properties of undefined (reading 'id')
    at getTypeListId (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:58078:34)
    at createTypeReference (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:58114:16)
    at createNormalizedTypeReference (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:59115:100)
    at instantiateTypeWorker (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:61599:63)
    at instantiateTypeWithAlias (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:61584:20)
    at instantiateType (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:61562:29)
    at resolveObjectTypeMembers (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:55820:77)
    at resolveTypeReferenceMembers (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:55843:5)
    at resolveStructuredTypeMembers (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:56666:11)
    at getSignaturesOfStructuredType (/Users/wasabi/workspace/typescript/crash/node_modules/typescript/lib/tsc.js:57363:24)

🙂 Expected behavior

For TypeScript not to crash and to display some appropriate error message (such as TS4109).

Additional information about the issue

• The number parts in the code are probably irrelevant to the issue: we still get the same crash after replacing number to string for example.

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Thank you.