Typescript IssueCommentEvent.issue type is never

[danielpza]

Trying to use type IssueCommentEvent accessing issue property yields never type:

import('@octokit/webhooks-definitions/schema').IssueCommentEvent['issue']

I would expect it to have some type, either Issue or some augmentation of it

Perhaps there's some conflict between the Issue type and specific type overwriting it it

[G-Rath]

That type doesn't resolve to never:

Could you provide some more information about your setup, such as your IDE and package versions?

[danielpza]

I'm using emacs with lsp-mode, but I got a similar error using the cli:

$ cat test-issue-type.ts 
type Issue = import('@octokit/webhooks-definitions/schema').IssueCommentEvent['issue'];

const a: Issue = {};

$ tsc --version
Version 4.1.3

$ tsc --noEmit test-issue-type.ts 
test-issue-type.ts:3:7 - error TS2322: Type '{}' is not assignable to type 'never'.

3 const a: Issue = {};
        ~


Found 1 error.

[G-Rath]

What does your tsconfig look like?

Could you also confirm if this happens if you use an static import? (i.e import { IssueCommentEvent } from "@octokit/webhooks-definitions/schema").

[danielpza]

Yes it happens using static imports

What does your tsconfig look like?

yep, looking at the tsconfig I found I had disabled the strict flag, enabling it fixes the issue, no other relevant modification were done to the tsconfig:

{
  "compilerOptions": {
    "target": "es5",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', or 'ESNEXT'. */
    "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', or 'ESNext'. */
    "checkJs": true,                       /* Report errors in .js files. */

    /* Strict Type-Checking Options */
    "strict": false,                           /* Enable all strict type-checking options. */
    "esModuleInterop": true,                  /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */

    /* Advanced Options */
    "skipLibCheck": true,                     /* Skip type checking of declaration files. */
    "forceConsistentCasingInFileNames": true  /* Disallow inconsistently-cased references to the same file. */
  }
}

To be clear changing to strict: true shows the correct type.

[G-Rath]

Interesting, it's because of strictNullChecks - it seems that it doesn't like the fact that closed_at is null so somehow the type becomes type never.

Maybe it's because when that flag is false null is effectively removed, so it's seeing it as never instead? 🤔

Sadly there's not really a lot we can do as the type is correct and valid.
You might have luck over at the TypeScript repo getting this classed as a bug.

[danielpza]

I think I'm ok with enabling strictNullChecks, thanks for the help