Error not issued when global type is an alias of an object type literal

🔎 Search Terms

array, constructor, bracket

🕗 Version & Regression Information

• This is a crash

⏯ Playground Link

https://www.typescriptlang.org/dev/bug-workbench/?noLib=true&target=99&ts=5.5.0-dev.20240227#code/PTAEAEDsHsBkEsBGAuUAXATgVwKYCgQI0BDDAcxzVRwGdIcAPNPPAExwGMAbUnUMrtETEuoAN55QoDtEg00oAIIYMxAJ6oJUqQB4AKqAC8oLJADWMAO6QAfAAoAdE9JkayYpDUBtALoBKVGVVNX0bSW16S1B9IxNzK0gAGnsnBxc3D29-QJV1UPCAXxYpNDUABz4gvL0bWK1tL3hUSCwAW0QcDB9UPXCpLhxIMjQAC2a2joxCvCKCMBFRaAAzdBG+DsEosngANz4AIgAFDGgKjFLQAHIBodHL0HgaUFbHmnghh8h0cr5LsQLLql9sg8ABuUB2LwARkSoAATLCAMz+UA0YhoR5LeC0JS5EItdqdGygsEQ6GwhGgZF+VHozHYp5iUA3YZjUAEyagAok9jcXjSWTyUCkKHNHB7DC+Uki2kYmhYnFMlmjcaEjBcnmcHgYPgyOQKUhw1WTKXgw2y+mK5mDVnGzpclhzVaPVEjaBYLisVYnKIeUCdE7qxBYBTwBSsaC0SCXZiEcBoGgAWkYFQ4aGTKmgU3BkJ8wqeHM6vhpaLlCqe8gw7zIUrwKazCiZBSAA

💻 Code

// @noLib: true
// @target: esnext

declare global {
  const Array: {
    <T = unknown>(...args:any[]): Array<T>
    new <T = unknown,>(...args:any[]): Array<T>
  }

  type Array<T> = {
    [i: number]: T
    length: number
  }
}

// all of the below give "Property 'length' is missing in type '{}'...":
; ([1, 2, 3]) satisfies Array<number>;
; ([1, 2, 3]) satisfies { length: number };
declare const ar1: never[]
; ar1 satisfies { length: number };
declare const ar2: number[]
; ar2 satisfies { length: number }


// this should throw an error but it doesn't
// @ts-expect-error
; ([] as number[]) satisfies string[]

export { }

🙁 Actual behavior

Types created with the T[] and objects created with the [x as T] syntax are not typed as Array<T> but instead as {}.

🙂 Expected behavior

I expect either:

• T[] syntax and Array<T> to be completely synonymous
• A compiler error that the Array type is not an instantiable type

Additional information about the issue

Related to #57009.

Start with the linked TypeScript bug-workbench Playground repro and compare the behavior of T[] with Array when global Array is an object type literal. Trace how the compiler handles the global Array alias, array syntax, and assignability. Done means either both forms behave synonymously or the invalid Array type produces a compiler error, with the repro expectations covered by a regression test.