repository.findOne(entity.constructor) returns an entity even if FindConditions don't exists

[carlosdubus]

Issue type:

[x] question
[x] bug report

Database system/driver:

[x] mysql / mariadb

TypeORM version:

[x] latest

Steps to reproduce or a small repository showing the problem:

I know I should provide User class itself to findOne, but I found myself using obj.constructor to save an entity. Looks like TypeScript skips the type validation of FindConditions<T> because T is an {} I think. Nevertheless it shouldn't return an entity that does not match the FindConditions provided. Correct me if I'm wrong. Thanks!

import {Entity, PrimaryGeneratedColumn, Column, getManager, createConnection} from "typeorm";

@Entity()
export class User {
    @PrimaryGeneratedColumn()
    id: number;
    @Column()
    name: string;
}

async function main() {
    await createConnection(); // create connection somehow
    var search = {fieldNotExists: "1"}; // field does not exists on User class
    var user = new User();
    var r = await getRepository<User>(user.constructor).findOne(search);
    console.log(r); // returns first entity of table instead of undefined
}

main();

[vlapo]

Duplicate of #3416. We just discuss about this problem. Unknown fields are stripped from query so result condition is {} and it is returned first entity in table.