Types are inferred too narrow from template strings in a readonly object starting from TypeScript 4.7

[graphemecluster]

Bug Report

Credit: Translate from this tweet by @MH4GF

Version & Regression Information: This changed between versions 4.6 and 4.7

Code: Playground link with relevant code

const prefix = 'prefix'

// Inferred as an array of specific string when putting the key/value [of an object] with Object.freeze and template string into an array
const freezeWithTplObj = Object.freeze({
    foo: `${prefix}foo`
})
const ary1 = [freezeWithTplObj.foo];
// => ary1: "prefixfoo"[]
// [Transl. Note] Used to be string[] prior to 4.7

// [Inferred as] a string array with only template string
const tplObj = {
    foo: `${prefix}foo`
}
const ary2 = [tplObj.foo];
// => ary2: string[]

// [Inferred as] a string array with only Object.freeze
const freezeObj = Object.freeze({
    foo: "foo"
})
const ary3 = [freezeObj.foo];
// => ary3: string[]

// [Inferred as] a string array with neither Object.freeze nor template string
const obj = {
    foo: "foo"
}
const ary4 = [obj.foo];
// => ary4: string[]

Actual behavior: ary1 inferred as "prefixfoo"[]

Expected behavior: ary1 inferred as string[]

[RyanCavanaugh]

This was a requested behavior for Object.freeze to mimic the behavior you get when writing

const tplConst = {
    foo: `${prefix}foo`
} as const;

[RyanCavanaugh]

e.g. #10725 (comment)

[typescript-bot]

This issue has been marked 'Working as Intended' and has seen no recent activity. It has been automatically closed for house-keeping purposes.