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Parameters<FnInterface> return only last overload arguments type #34432

@iamolegga

Description

@iamolegga

TypeScript Version: 3.7.x-dev.201xxxxx ("nightly" on http://www.typescriptlang.org/play/)

Search Terms:
typescript parameters of overloading function interface

Code

interface LogFn {
  // move lines oreder to see different behavior 
  (msg: string, ...args: any[]): void;
  (obj: object, msg?: string, ...args: any[]): void;
}

class Logger {
  private readonly logger!: LogFn;

  log(...args: Parameters<LogFn>) {
    this.logger(...args);
  }
}

const loggerInstance = new Logger();

loggerInstance.log('test');
                   ^^^^^^ Argument of type '"test"' is not assignable to parameter of type 'object'.(2345)
loggerInstance.log({});

Expected behavior:
Parameters<FnInterface> should return all types of arguments

Actual behavior:
Parameters<FnInterface> return only last overload arguments type

Playground Link: http://www.typescriptlang.org/play/?ts=Nightly&ssl=1&ssc=1&pln=19&pc=1#code/JYOwLgpgTgZghgYwgAgDIHsDmAxEyDeAUMsgPSnIC26AbigDagQDOy6UEAJtMmOsswgpOwGDGgRwyAEYQAFnBrB2yYsgAUlZpgBcAsFFCYANMgB0FuFEzM9cEAE8A2gF0AlHprpgnANxr1dGkAKz0g4IgEMFMtTAB+PWYDI1MLMysbO0dXD2QvH38AX0JCBHo4ZlYMTEweIhIAB0MaOEhkDjhOdBB6B2R6LFqoAEI9atx-NQHMdTSM22QABSs4SghIKGYAHnGQAD43AjUSMDlgZjNpodnLa2Y3fxJi4tLupP7B6ABJECT7JGQAF5kCAIAB3NCfKDqB4lK7fX5gf4QS5YdQAckgSXRsPhUB+fxASFRM3whVhQA

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