Interpolations without provided value should remain in the translation result

[rubenduiveman]

Clear and concise description of the problem

We're upgrading to v9.x. When translating a string, we want to perform some extra logic on the result, using special tags {tag} to be replaced in the translated result. In V8, the translated value still contained those values, but in V9 it doesn't anymore.

Input: { val: "I am a special {tag} string" }, calling t("val").
V8 result: I am a special {tag} string
V9 result: I am a special string

Suggested solution

Let's add an option to createI18n to toggle between those behaviors globally if it's not there.

Alternative

No response

Additional context

No response

Validations

• Read the Contributing Guidelines
• Read the Documentation
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[JvanderHeide]

Currently missing exactly this behaviour.

E.g.: with the following translation key:

en:
  form.validations.xxx: '{label} should be at least {min} characters'

In combination with Zod for validation:

message: i18n.t("form.validations.xxx", {
  min: issue.minimum
})

The actual outcome is: should be at least 1 characters,
Whereas I expect to find {label} should be at least 1 characters, for re-use later on like so:

{{ t(errorMessage, {label, name, inputValue}, {resolvedMessage: true}) }

My current work around is to manually map the missing keys back to their respective placeholders:

message: i18n.t("form.validations.xxx", {
  min: issue.minimum,
  label: '{label}',
  name: '{name}',
  inputValue: '{inputValue}'
})