Deep nested validation broken

Description

When trying to validate nested objects using @ValidateNested(), whitelist: true and forbidNonWhitelisted: true, error "property XY should not exist" gets thrown for no apparent reason.

Reproduction

Here a vastly simplified version of my use case:

class ProductPricing {
    @Type(() => ProductPricingOptionsDTO)
    options: ProductPricingOptionsDTO;
}

class ProductPricingOptionsDTO{
    @ValidateNested()
    @Type(() => OnlineUserPricingOptionsDTO)
    onlineUserPrices: OnlineUserPricingOptionsDTO;
}

class OnlineUserPricingOptionsDTO{
    @IsNumber()
    @Min(2)
    price: number;
}

and validating the following payload:

{
    "options": {
        "onlineUserPrices": {
            "price": 2
        }
    }
}

with whitelist: true, forbidNonWhitelisted: true throws an error containing the following message:

"constraints": {
    "whitelistValidation": "property price should not exist"            }
}

Environment

• nodejs:
• browser:
• typeorm:

class-validator version: ^0.12.1

[murbanowicz]

Cheers! We have found out that adding @Type(() => NestedType) was the thing. It works without adding that parameter which you suggested. Adding comment for “future generations”.

[gabrieloczkowski]

Hi! I had the same issue but I managed to resolve it by using:

transformOptions: {
    enableImplicitConversion: true,
},

Please let me know if it helped also in your cases.