Maximum call stack size exceeded while inferring conditional type. #22950

kpdonn · 2018-03-28T15:14:27Z

TypeScript Version: 2.9.0-dev.20180328

The code below fails with a "Maximum call stack size exceeded" error. I actually came across this while trying to make a minimal example of a separate problem which is why the code looks so useless.

Code

type AProp<T extends { a: string }> = T

declare function myBug<
  T extends { [K in keyof T]: T[K] extends AProp<infer U> ? U : never }
>(arg: T): T

const out = myBug({obj1: {a: "test"}})

Additional similar case that started crashing later. Following code does not crash in 2.8.1 but does in typescript@next

type Value<V extends string = string> = Record<"val", V>;
declare function value<V extends string>(val: V): Value<V>;

declare function ensureNoDuplicates<
  T extends {
    [K in keyof T]: Extract<T[K], Value>["val"] extends Extract<T[Exclude<keyof T, K>], Value>["val"]
      ? never
      : any
  }
>(vals: T): void;

const noError = ensureNoDuplicates({main: value("test"), alternate: value("test2")});

const shouldBeNoError = ensureNoDuplicates({main: value("test")});

const shouldBeError = ensureNoDuplicates({main: value("dup"), alternate: value("dup")});

Actual behavior:

[Error  - 09:54:19] 'quickinfo' request failed with error.
Error processing request. Maximum call stack size exceeded
RangeError: Maximum call stack size exceeded
    at resolveEntityName (tsserver.js:22816:35)
    at getSymbolOfEntityNameOrPropertyAccessExpression (tsserver.js:40471:24)
    at getSymbolAtLocation (tsserver.js:40512:28)
    at getTypeFromTypeNode (tsserver.js:28216:34)
    at containsReference (tsserver.js:28397:79)
    at visitNode (tsserver.js:12757:24)
    at Object.forEachChild (tsserver.js:12867:24)
    at containsReference (tsserver.js:28401:27)
    at visitNode (tsserver.js:12757:24)
    at Object.forEachChild (tsserver.js:12894:24)
    at containsReference (tsserver.js:28401:27)
    at visitNode (tsserver.js:12757:24)
    at Object.forEachChild (tsserver.js:12884:24)
    at isTypeParameterPossiblyReferenced (tsserver.js:28388:31)
    at tsserver.js:27929:146
    at Object.filter (tsserver.js:1671:31)
    at getTypeFromConditionalTypeNode (tsserver.js:27929:92)
    at getTypeFromTypeNode (tsserver.js:28211:28)
    at getTemplateTypeFromMappedType (tsserver.js:26007:52)
    at substituteIndexedMappedType (tsserver.js:27818:36)
    at getSimplifiedIndexedAccessType (tsserver.js:27810:28)
    at getConstraintOfIndexedAccess (tsserver.js:26146:31)
    at getConstraintOfType (tsserver.js:26138:40)
    at getConstraintForRelation (tsserver.js:29333:80)
    at structuredTypeRelatedTo (tsserver.js:29404:38)
    at recursiveTypeRelatedTo (tsserver.js:29315:53)
    at isRelatedTo (tsserver.js:29031:38)
    at checkTypeRelatedTo (tsserver.js:28882:26)
    at isTypeRelatedTo (tsserver.js:28864:24)
    at Function.compareTypesAssignable [as compareTypes] (tsserver.js:28584:20)
    at getInferredType (tsserver.js:30913:34)
    at mapper (tsserver.js:30436:32)
    at instantiateType (tsserver.js:28464:28)
    at getConditionalType (tsserver.js:27888:60)
    at getTypeFromConditionalTypeNode (tsserver.js:27943:38)
    at getTypeFromTypeNode (tsserver.js:28211:28)
    at getTemplateTypeFromMappedType (tsserver.js:26007:52)
    at substituteIndexedMappedType (tsserver.js:27818:36)
    at getSimplifiedIndexedAccessType (tsserver.js:27810:28)
    at getConstraintOfIndexedAccess (tsserver.js:26146:31)
    at getConstraintOfType (tsserver.js:26138:40)
    at getConstraintForRelation (tsserver.js:29333:80)
    at structuredTypeRelatedTo (tsserver.js:29404:38)
    at recursiveTypeRelatedTo (tsserver.js:29315:53)
    at isRelatedTo (tsserver.js:29031:38)
    at checkTypeRelatedTo (tsserver.js:28882:26)
    at isTypeRelatedTo (tsserver.js:28864:24)
    at Function.compareTypesAssignable [as compareTypes] (tsserver.js:28584:20)
    at getInferredType (tsserver.js:30913:34)
    at mapper (tsserver.js:30436:32)
    at instantiateType (tsserver.js:28464:28)
    at getConditionalType (tsserver.js:27888:60)
    at getTypeFromConditionalTypeNode (tsserver.js:27943:38)
    at getTypeFromTypeNode (tsserver.js:28211:28)
    at getTemplateTypeFromMappedType (tsserver.js:26007:52)
    at substituteIndexedMappedType (tsserver.js:27818:36)
    at getSimplifiedIndexedAccessType (tsserver.js:27810:28)
    at getConstraintOfIndexedAccess (tsserver.js:26146:31)
    at getConstraintOfType (tsserver.js:26138:40)
    at getConstraintForRelation (tsserver.js:29333:80)
    at structuredTypeRelatedTo (tsserver.js:29404:38)
    at recursiveTypeRelatedTo (tsserver.js:29315:53)
    at isRelatedTo (tsserver.js:29031:38)
    at checkTypeRelatedTo (tsserver.js:28882:26)
    at isTypeRelatedTo (tsserver.js:28864:24)
    at Function.compareTypesAssignable [as compareTypes] (tsserver.js:28584:20)
    at getInferredType (tsserver.js:30913:34)
    at mapper (tsserver.js:30436:32)
    at instantiateType (tsserver.js:28464:28)
    at getConditionalType (tsserver.js:27888:60)
    at getTypeFromConditionalTypeNode (tsserver.js:27943:38)
    at getTypeFromTypeNode (tsserver.js:28211:28)
    at getTemplateTypeFromMappedType (tsserver.js:26007:52)
    at substituteIndexedMappedType (tsserver.js:27818:36)
    at getSimplifiedIndexedAccessType (tsserver.js:27810:28)
    at getConstraintOfIndexedAccess (tsserver.js:26146:31)
    at getConstraintOfType (tsserver.js:26138:40)
    at getConstraintForRelation (tsserver.js:29333:80)
    at structuredTypeRelatedTo (tsserver.js:29404:38)
    at recursiveTypeRelatedTo (tsserver.js:29315:53)
    at isRelatedTo (tsserver.js:29031:38)
    at checkTypeRelatedTo (tsserver.js:28882:26)
    at isTypeRelatedTo (tsserver.js:28864:24)
    at Function.compareTypesAssignable [as compareTypes] (tsserver.js:28584:20)
    at getInferredType (tsserver.js:30913:34)
    at mapper (tsserver.js:30436:32)
    at instantiateType (tsserver.js:28464:28)
    at getConditionalType (tsserver.js:27888:60)
    at getTypeFromConditionalTypeNode (tsserver.js:27943:38)
    at getTypeFromTypeNode (tsserver.js:28211:28)
    at getTemplateTypeFromMappedType (tsserver.js:26007:52)
    at substituteIndexedMappedType (tsserver.js:27818:36)
    at getSimplifiedIndexedAccessType (tsserver.js:27810:28)
    at getConstraintOfIndexedAccess (tsserver.js:26146:31)
    at getConstraintOfType (tsserver.js:26138:40)
    at getConstraintForRelation (tsserver.js:29333:80)
    at structuredTypeRelatedTo (tsserver.js:29404:38)
    at recursiveTypeRelatedTo (tsserver.js:29315:53)
    at isRelatedTo (tsserver.js:29031:38)
    at checkTypeRelatedTo (tsserver.js:28882:26)

Playground Link:
Link

Related Issues:
Multiple "Maximum call stack size exceeded" issues exist but looking at the recent ones I did not notice any that were obvious duplicates.

The text was updated successfully, but these errors were encountered:

mhegazy · 2018-03-28T17:16:13Z

I am not sure why you are writing a constraint this way, it seems to me that this should just be declare function myBug<T extends Record<string, {a:string}>>(arg: T): T, on any rate, we should not crash.

kpdonn · 2018-03-28T19:42:44Z

Agreed the code isn’t meaningful at all. I was in the process of writing something longer that wouldn’t have been so pointless when I stumbled onto this crash and figured the crash was a bug regardless of the code.

mhegazy · 2018-03-28T20:38:50Z

constraining a generic type of a mapped type on itself is not that useful of a patter i would say.

kpdonn · 2018-03-29T00:44:28Z

You'd be surprised then. I've been using the pattern to successfully create compile errors if duplicate keys are found in an api that shouldn't accept duplicates.

Simple-ish example I came up with from #22679:

type ArrayKeys = keyof any[]
type Indices<T> = Exclude<keyof T, ArrayKeys>
type GetUnionKeys<U> = U extends Record<infer K, any> ? K : never
type CombineUnion<U> = { [K in GetUnionKeys<U>]: U extends Record<K, infer T> ? T : never }
type Combine<T> = CombineUnion<T[Indices<T>]>

declare function combine2<
  T extends object[] &
    {
      [K in Indices<T>]: {
        [K2 in keyof T[K]]: K2 extends GetUnionKeys<T[Exclude<Indices<T>, K>]> ? never : any
      }
    } & { "0": any }
>(objectsToCombine: T): Combine<T>

const result2 = combine2([{ foo: 534 }, { bar: "test" }])
// in TS 2.8 result2 has type {foo: number, bar: string}

const error2 = combine2([{ foo: 534, dupKey: "dup1" }, { bar: "test", dupKey: "dup2" }])
// Actually has an error here as intended because of dupKey in both objects

Playground Link

And it's not ready for anyone to use or even really read yet but I've been experimenting with more complicated use cases that might end up being very practical: Example

Cryrivers · 2018-05-09T03:54:19Z

Here's a meaningful case that triggers Maximum call stack size exceeded in TypeScript 2.9 Dev.

https://github.com/DefinitelyTyped/DefinitelyTyped/blob/65b176eaefc9a53c8e9cc615d290cb927947a6bb/types/react-redux/index.d.ts#L66

tsc crashes unless the conditional type is removed.

Cryrivers · 2018-05-23T02:25:01Z

Update: I believe this bug has been fixed in 2.9.1 insiders build.

mhegazy added the Bug A bug in TypeScript label Mar 28, 2018

mhegazy assigned ahejlsberg Mar 28, 2018

mhegazy added this to the TypeScript 2.9 milestone Mar 28, 2018

mhegazy modified the milestones: TypeScript 2.9, TypeScript 2.9.1 May 8, 2018

mhegazy modified the milestones: TypeScript 2.9.1, TypeScript 3.0 May 23, 2018

mhegazy modified the milestones: TypeScript 3.0, TypeScript 3.1 Jul 2, 2018

mattmccutchen mentioned this issue Jul 17, 2018

Compiler stack overflow with circular constraint and conditional type #25740

Closed

mattmccutchen mentioned this issue Aug 14, 2018

Stack overflow with circular mapped type and conditional type #26448

Closed

ahejlsberg mentioned this issue Aug 20, 2018

Fix infinite constraints #26558

Merged

ahejlsberg added the Fixed A PR has been merged for this issue label Aug 20, 2018

ahejlsberg closed this as completed in #26558 Aug 22, 2018

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Maximum call stack size exceeded while inferring conditional type. #22950

Maximum call stack size exceeded while inferring conditional type. #22950

kpdonn commented Mar 28, 2018 •

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mhegazy commented Mar 28, 2018

kpdonn commented Mar 28, 2018

mhegazy commented Mar 28, 2018

kpdonn commented Mar 29, 2018 •

edited

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Cryrivers commented May 9, 2018

Cryrivers commented May 23, 2018

Maximum call stack size exceeded while inferring conditional type. #22950

Maximum call stack size exceeded while inferring conditional type. #22950

Comments

kpdonn commented Mar 28, 2018 • edited Loading

mhegazy commented Mar 28, 2018

kpdonn commented Mar 28, 2018

mhegazy commented Mar 28, 2018

kpdonn commented Mar 29, 2018 • edited Loading

Cryrivers commented May 9, 2018

Cryrivers commented May 23, 2018

kpdonn commented Mar 28, 2018 •

edited

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kpdonn commented Mar 29, 2018 •

edited

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