JSON Module members not considered part of string literal type

[wegry]

TypeScript Version: 4.0.2 and 4.1.0-dev.20200821

Search Terms:
json module tagged union typescript
json module string literal type typescript brings up https://stackoverflow.com/questions/54352128/typescript-convert-string-in-json-to-string-literal with no answer.

Code
https://github.com/wegry/json-modules-and-string-literal-types

// index.ts
import * as json from './index.json'

type Schema = {
  $schema: {
    declarations: Record<string, { type: 'string' | 'number' }>
  }
}

const usage: Schema = json

console.log(usage)

with a index.json like so.

{
  "$schema": {
    "declarations": {
      "name": {
        "type": "string"
      }
    }
  }
}

Expected behavior:
tsc should reconcile "string" to be a member of the string literal type in defined at $schema.declarations.name.type.

Actual behavior:

$ tsc
index.ts:9:7 - error TS2322: Type '{ $schema: { declarations: { name: { type: string; }; }; }; }' is not assignable to type 'Schema'.
  The types of '$schema.declarations' are incompatible between these types.
    Type '{ name: { type: string; }; }' is not assignable to type 'Record<string, { type: "string" | "number"; }>'.
      Property '"name"' is incompatible with index signature.
        Type '{ type: string; }' is not assignable to type '{ type: "string" | "number"; }'.
          Types of property 'type' are incompatible.
            Type 'string' is not assignable to type '"string" | "number"'.

9 const usage: Schema = json
        ~~~~~


Found 1 error.

[MartinJohns]

You want #32063.

[wegry]

Closing as duplicate of #32063.