microsoft / microsoft/TypeScript

Crash when defining `Array` type via `[]` syntax

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Bug Domain: check: Type Circularity Has Repro Help Wanted
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Description

🔎 Search Terms

Array type define crash

🕗 Version & Regression Information
  • This is a crash
⏯ Playground Link

https://www.typescriptlang.org/dev/bug-workbench/?noLib=true#code/PTAEAEDsHsBkEsBGAuUAXATgVwKYCg0BPABx1AEEMMBDQgHgBUA+UAXlAYG0BdAbjyA

💻 Code
// @noLib: true
type Array<T> = T[];
🙁 Actual behavior

Typescript crashes:

createDeferredTypeReference@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:52280:42
getTypeFromArrayOrTupleTypeNode@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:52908:93
getTypeFromTypeNodeWorker@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:54875:20
getTypeFromTypeNode@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:54828:45
getDeclaredTypeOfTypeAlias@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:49869:33
tryGetDeclaredTypeOfSymbol@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:49955:18
getDeclaredTypeOfSymbol@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:49948:16
getTypeOfGlobalSymbol@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:52644:45
getGlobalType@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:52678:42
initializeTypeChecker@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:75719:27
createTypeChecker@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:42674:7
getTypeChecker@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:101959:46
synchronizeHostDataWorker@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:121935:17
synchronizeHostData@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:121830:11
getProgram@https://typescript.azureedge.net/cdn/5.4.0-dev.20240110/monaco/dev/vs/language/typescript/tsWorker.js:121997:9
updateFile@https://www.typescriptlang.org/17821066377c4486a980330106160c805ea5b4a9-5466acbcf54af90f679c.js:1:25348
G@https://www.typescriptlang.org/17821066377c4486a980330106160c805ea5b4a9-5466acbcf54af90f679c.js:1:17599
F@https://www.typescriptlang.org/17821066377c4486a980330106160c805ea5b4a9-5466acbcf54af90f679c.js:1:17638
A@https://www.typescriptlang.org/component---src-pages-dev-bug-workbench-tsx-6a9bdea3e00be7d97087.js:1:40663
9796/M/
🙂 Expected behavior

I expect an error message.

Additional information about the issue

No response

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Reproduce the crash with the linked playground or the // @noLib: true example. Start by tracing getTypeFromArrayOrTupleTypeNode and createDeferredTypeReference from the reported stack, then add a regression test for the self-referential Array<T> = T[] case. Done means the compiler reports an error instead of crashing.

Written by the indexing model from the issue text.

Assessment

Tech stack
typescript
Domain
compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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