[BUG] [typescript-angular] Base Path can't be set to '<empty string>'

Created by: DanielHabenicht

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• What's the version of OpenAPI Generator used?
• Have you search for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Bounty to sponsor the fix (example)

Description

If the basePath in the config is set to '' (empty string). The configuration is ignored and 'http://localhost' is used instead. That is unexpected behaviour.

Background

The basePath of the typescript-angular generated Files are currently set to 'http://localhost' (as a Fallback). When trying to setup the basePath to '' (empty String) the config is not used as the generated line of code configuration.basePath || basePath || this.basePath; is evaluated to false, because empty string in javascript is false.

  protected basePath = 'http://localhost';
  public configuration = new Configuration();

  constructor(
    protected httpClient: HttpClient,
    @Optional() @Inject(BASE_PATH) basePath: string,
    @Optional() configuration: Configuration
  ) {
    if (configuration) {
      this.configuration = configuration;
      this.configuration.basePath = configuration.basePath || basePath || this.basePath;
    } else {
      this.configuration.basePath = basePath || this.basePath;
    }
  }

openapi-generator version

4.0.0-beta2

OpenAPI declaration file content or url

Command line used for generation

npm install @openapitools/openapi-generator-cli@0.0.8-4.0.0-beta2
openapi-generator generate -i swagger.json -g typescript-angular -o projects/client-api/src/lib/ --additional-properties="ngVersion=6.1.7" --additional-properties="supportsES6=true"

Steps to reproduce

1. Generate typescript-angular package from openapi.config
2. Configure the ApiModule in app.module.ts
3. Use a service from the generated typescript-angular package.

Related issues/PRs

Nothing found.

Suggest a fix

Two ways:

1. Remove the fallback basePath by setting it to '' (empty string)
2. Fix the evalutation basePath property.