[Typescript-Angular] for upload multi file in blob array

Description

was trying to upload file with blob array (Array<Blob>)
function is generate incomplete with codegen

first issues:
let formParams: { append(param: string, value: any): void; };
prompt error on formParams = formParams.append('request', <any>element) || formParams; during compile.

have to manually change void to any after generate

second issues:

const consumes: string[] = [
            'multipart/form-data'
        ];

consumes initial as array, with multipart/form-data
but useForm is false, (suppose assign useForm = canConsumeForm in this case)
change the code to useForm = canConsumeForm on my case

expecting result:
post with binary file, not [object file]

example bug code:

public test(request?: Array<Blob>, observe: any = 'body', reportProgress: boolean = false): Observable<any> {
    const consumes: string[] = [
        'multipart/form-data'
     ];
    const canConsumeForm = this.canConsumeForm(consumes);
    let formParams: { append(param: string, value: any): void; };
    let useForm = false;
}

workable code:

public test(request?: Array<Blob>, observe: any = 'body', reportProgress: boolean = false): Observable<any> {
    const consumes: string[] = [
        'multipart/form-data'
     ];
    const canConsumeForm = this.canConsumeForm(consumes);
    let formParams: { append(param: string, value: any): any; };
    let useForm = canConsumeForm;
}

Swagger-codegen version

3.0.24

Swagger declaration file content or url

not suitable to share here, sorry

Command line used for generation

swagger-codegen generate -i <url> -l typescript-angular --additional-properties ngVersion=9.0.0

Related issues/PRs

yes, but no actual solution

Run the shown swagger-codegen command for the typescript-angular generator using a minimal multipart/form-data definition that accepts Array, then compare the generated client with the reported snippets. Done means the generated TypeScript compiles without changing append’s return type and posts the files as binary multipart data.