Cannot import in 3.0.1: A declaration file cannot be imported without 'import type'

[perrin4869]

I can't find other reports here yet, but I ran into #3588 like everyone else, but unfortunately the fix introduced a new error in my case:

../../node_modules/date-fns/index.d.mts(1,15): error TS2846: A declaration file cannot be imported without 'import type'. Did you mean to import an implementation file './index.js' instead?

I am guessing this might be the reason that import type was there originally in 3.0.0. Not quite sure what the fix is though, it's quite surprising...
I can try to put together a reproduction later

[kossnocorp]

Hey! I expected that, but I couldn't reproduce it. I'd appreciate it if you could produce a minimal repro example.

[kossnocorp]

@perrin4869 please try date-fns@3.0.2-rc.1. I still need repro to add to smoke tests, but I hope it finally fixes the problem.

[perrin4869]

beautiful, that seems to have done the trick!!! thanks!!
I'll put together a repro soon 😃

[nstuyvesant]

I ran into this as well.

@kossnocorp - I see the solution in 3.0.2-rc.1 is to copy the contents of the .d.ts files to the .d.mts files.

Why not just modify the exports in the package.json and do away with all the .d.mts files? TypeScript won't care about the extension as long as the exports are setup correctly. You could simplify the exports as well...

Each export like this one...

    "./addMinutes": {
      "require": {
        "types": "./addMinutes.d.ts",
        "default": "./addMinutes.js"
      },
      "import": {
        "types": "./addMinutes.d.mts",
        "default": "./addMinutes.mjs"
      }
    },

could be reduced to...

    "./addMinutes": {
      "types": "./addMinutes.d.ts",
      "require":  "./addMinutes.js"
      "import":  "./addMinutes.mjs"
    },

[kossnocorp]

@nstuyvesant I think you're right, and it's possible to point to the same d.ts. I tried many combinations to make "Are types wrong" happy, and this one seems to have slipped away.

Regarding reducing, it's possible as it will give another error.

[kossnocorp]

Shipped the fix with date-fns@3.0.2

[kossnocorp]

Unfortunately, I messed up attw results, and pointing to the same d.ts indeed gives the error: https://github.com/arethetypeswrong/arethetypeswrong.github.io/blob/main/docs/problems/FalseCJS.md

So I rolled back to the original solution by copying the content and released it as date-fns@3.0.3