class-validator feature: Range decorator for numbers

Description

There are two string length check decorators: @MinLength and @MaxLength. Additionally, there is a string decorator @Length(min, max) which checks if string length is in range between min and max.
As a developer, having @Min and @Max decorators for numbers, which works similar to @MinLength and @MaxLength, I would expect the third, @Range(min, max) decorator, to be delivered with class-validator.

Proposed solution

Create a new @Range decorator for numbers, which is a combination of Min and Max decorators.

Code implementation suggestion:

import { ValidationOptions } from '../ValidationOptions';
import { buildMessage, ValidateBy } from '../common/ValidateBy';

export const RANGE = 'range';

/**
 * Checks if the first number is greater than or equal to the second and less than or equal to the third.
 */
export function range(num: unknown, min: number, max: number): boolean {
  return typeof num === 'number' && typeof max === 'number' && typeof min === 'number' && min <= num <= max;
}

/**
 * Checks if the value is greater than or equal to the allowed minimum value and less than or equal to the allowed maximum value.
 */
export function Range(minValue: number, maxValue: number, validationOptions?: ValidationOptions): PropertyDecorator {
  return ValidateBy(
    {
      name: RANGE,
      constraints: [minValue, maxValue],
      validator: {
        validate: (value, args): boolean => range(value, args?.constraints[0], args?.constraints[1]),
        defaultMessage: buildMessage(
          eachPrefix => eachPrefix + '$property must be greater than or equal to $constraint1 and less than or equal to $constraint2',
          validationOptions
        ),
      },
    },
    validationOptions
  );
}

It would simplify code for typical use case like this:

@Min(1)
@Max(10)
priority: number

The same conditions with new decorator would look like this:

@Range(1, 10)
priority: number

Nov 03 '24 19:11 rastorc3v

Take into account that there may be conflicts with using Range as a decorator name, as shown in the screenshots. This name is already associated with the Range interface in the DOM API, which could lead to confusion or potential conflicts.

Possible alternatives:

@ValueRange()
@MinMaxRange()
@Between()
@WithinRange()