Trans component defaultValue not working for empty string

[Peter554]

🐛 Bug Report

The Trans component defaultValue is not working for an empty string. Both for a string and for a function returning a string.

defaultValue: ""
// or
defaultValue: (lng, ns, key, options) => ""

That's important for me as I have a use case

defaultValue: (lng, ns, key, options) => lng === "foo" ? key : ""

To Reproduce

See these tests added on my fork - Peter554@de803c5.

When I run the tests they fail:

--- expected                                                                                                           
  +++ actual                                                                                                             
  @@ -1,3 +1,3 @@                                                                                                        
   Object {                                                                                                              
  -  "Trans component should respect the defaultValue option": "",                                                       
  +  "Trans component should respect the defaultValue option": "Trans component should respect the defaultValue option", 
   }

You can also see the tests failing here - #194 - running in your CI (I made a draft PR to demonstrate).

Expected behavior

I expect the tests to pass.

Your Environment

• runtime version: node v10.19.0
• i18next version: 19.7.0
• os: Linux