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Function signature confusion after ternary operator #35707

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@Mickael-van-der-Beek

Description

@Mickael-van-der-Beek

I'm expecting this to not be a bug but I can't seem to figure out what else it could be.
Basically I'm trying to create a (TLS)Socket instance using the core Node.js net or tls modules depending on a condition.
Instantiating them by directly referencing the module works fine but whenever I introduce a level of indirection by conditionally defining the TCP client module, compilation breaks.

Code

import net from 'net';
import tls from 'tls';

const socketA = net.connect({ host: 'localhost', port: 1234 });
const socketB = tls.connect({ host: 'localhost', port: 1234 });

const protocol = process.argv[2];
const client = protocol === 'https' ? tls : net;
const socketC: net.Socket | tls.TLSSocket = client.connect({ host: 'localhost', port: 1234 });

console.log(socketA, socketB, socketC);

Expected behavior:

Successful compilation.

Actual behavior:

This expression is not callable.
  Each member of the union type
    '{ (options: NetConnectOpts, connectionListener?: (() => void) | undefined): Socket;
     (port: number, host?: string | undefined, connectionListener?: (() => void) | undefined): Socket; 
     (path: string, connectionListener?: (() => void) | undefined): Socket; } | { ...; }'
has signatures, but none of those signatures are compatible with each other.

12 const socketC = client.connect({ host: 'localhost', port: 443 });
                          ~~~~~~~

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