[Preview Types] Conflict with `@types/ember__test-helpers`

🐞 Describe the Bug

Trying to use the new preview-types instead of DefinitelyTyped ones doesn’t work as there are errors in node_modules.

🔬 Minimal Reproduction

ember new preview-types-bug # make sure you use the latest `ember-cli` - 4.8.0
cd preview-types-bug
ember install ember-cli-typescript

Then follow the steps from the migration guide - i.e. remove the unneeded packages from package.json, run npm install, modify the preview-types-bug/types/preview-types-bug/index.d.ts file as shown there, and then run ./node_modules/.bin/tsc. You will get:

Found 111 errors in 25 files.

Errors  Files
    27  node_modules/@types/ember-data/index.d.ts:91
     5  node_modules/@types/ember/index.d.ts:87
     1  node_modules/@types/ember__application/index.d.ts:97
     2  node_modules/@types/ember__array/-private/enumerable.d.ts:163
     4  node_modules/@types/ember__array/-private/mutable-enumerable.d.ts:9
     7  node_modules/@types/ember__array/-private/native-array.d.ts:15
     4  node_modules/@types/ember__array/index.d.ts:19
     4  node_modules/@types/ember__array/mutable.d.ts:12
     1  node_modules/@types/ember__array/proxy.d.ts:6
     1  node_modules/@types/ember__component/-private/class-names-support.d.ts:24
     1  node_modules/@types/ember__component/-private/view-mixin.d.ts:55
     2  node_modules/@types/ember__controller/index.d.ts:52
     1  node_modules/@types/ember__engine/-private/container-proxy-mixin.d.ts:14
     1  node_modules/@types/ember__engine/-private/registry-proxy-mixin.d.ts:51
     1  node_modules/@types/ember__object/-private/action-handler.d.ts:27
     1  node_modules/@types/ember__object/-private/types.d.ts:75
    17  node_modules/@types/ember__object/core.d.ts:3
     1  node_modules/@types/ember__object/evented.d.ts:48
     7  node_modules/@types/ember__object/index.d.ts:13
     1  node_modules/@types/ember__object/internals.d.ts:1
    10  node_modules/@types/ember__object/mixin.d.ts:16
     4  node_modules/@types/ember__object/observable.d.ts:1
     1  node_modules/@types/ember__object/promise-proxy-mixin.d.ts:34
     3  node_modules/@types/ember__object/proxy.d.ts:3
     4  node_modules/@types/ember__service/index.d.ts:18

😕 Actual Behavior

A bunch of errors in node_modules.

🤔 Expected Behavior

No errors.

🌍 Environment

• Ember: 4.8.2
• Node.js/npm: Nodejs 19
• OS: Arch Linux
• Browser: N/A

➕ Additional Context

The problem is that @types/ember__test-helpers (which we shouldn’t remove according to the guide) requires @types/ember__application which in turn requires @types/ember which then requires everything. And there are conflicts between the preview types and the DefinitelyTyped ones.

cc @chriskrycho, @wagenet

[boris-petrov]

I believe this issue has been resolved with the latest versions of ember-qunit, ember-resolver and @ember/test-helpers. Thanks for the hard work!

[chriskrycho]

Makes sense. Basically, we need to tackle the rest of #20162 to get these resolved. That’s going to be my main focus for a bunch of the rest of this quarter, after getting #20234 done—hopefully next week, now that I’ve finished the work to implement RFC 0821, which we needed for the rest of this! That said, we (I!) could very much use the community’s help: there are a lot of packages which need types!