Error in angular-token.model.d.ts

[nzacca]

I'm submitting a...

• [ ] Regression (a behavior that used to work and stopped working in a new release)
• [x] Bug report
• [ ] Performance issue
• [ ] Feature request
• [ ] Documentation issue or request
• [ ] Other... Please describe:

Current behavior

When building with strictNullChecks=true, the following error is raised:

ERROR in node_modules/angular-token/lib/angular-token.model.d.ts(11,5): error TS2411: Property 'name' of type 'string | undefined' is not assignable to string index type 'string'.
node_modules/angular-token/lib/angular-token.model.d.ts(12,5): error TS2411: Property 'userType' of type 'string | undefined' is not assignable to string index type 'string'.

Expected behavior

No error.

What is the motivation / use case for changing the behavior?

I would like to be able to use this library with strictNullChecks set to true.

Environment

Angular-Token version: 7.0.1 Angular version: 7 Typescript version: 3.2.4 & 3.4.5

Bundler

• [x] Angular CLI (Webpack)
• [ ] Webpack
• [ ] SystemJS

Browser:

• [x] Chrome (desktop) version XX
• [ ] Chrome (Android) version XX
• [ ] Chrome (iOS) version XX
• [ ] Firefox version XX
• [ ] Safari (desktop) version XX
• [ ] Safari (iOS) version XX
• [ ] IE version XX
• [ ] Edge version XX

Others: N/A

Notes: The issue is with the RegisterData definition here:

https://github.com/neroniaky/angular-token/blob/master/projects/angular-token/src/lib/angular-token.model.ts#L19

The following proposed change to the index signature should work since the RegisterData definition with the named properties allows an undefined string value for userType and name:

export interface RegisterData {
  [key: string]: string | undefined;
}

See the following for a demo of the issue and solution.

Edit: Updated environment version to indicate Typescript version.