Type error on template literal with expression on Typescript 4.2

[elgorditosalsero]

🐛 Bug Report

On Typescript 4.2.x the typed t function throw a type error when using template literal with an expression.
The doc says that's handled by TS 4.2.x and the workaround of as const is required only in TS 4.1.

To Reproduce

1. Follow the guide for TS support on a project with TS 4.2.x.
2. Use an expression inside the t function with a template literal

t(`activities:bottomSheets.assumption.title.${activity._type}`)

Expected behavior

TS should not throw the error :)

Your Environment

• runtime version: Node 15.13.0, React Native 0.64, TS 4.2.4
• i18next version: 20.2.2
• os: Mac

[pedrodurek]

Hey @elgorditosalsero, typescript team ended up reverting the Template Literal Inference feature. You can find more info here.
You can see the discussion here as well: microsoft/TypeScript#42589, microsoft/TypeScript#41891
So that, as const is still needed 😞 . I'll update the document.

[pedrodurek]

I will let you know if anything changes

[elgorditosalsero]

Hi @pedrodurek, thx for the info, will check the issues!

Btw, I'm still having the error also with as const as the attached screenshots.

[pedrodurek]

Hey @elgorditosalsero, It seems to be missing some keys, for example:

{
  key: {
   a: 'a',
   b: 'b',
  }
}

c is missing here.

type Foo = 'a' | 'b' | 'c';
const foo: Foo = 'b';
...
t(`key.${foo}`);

[elgorditosalsero]

@pedrodurek Thx for the tips, my fault on the translation file!