`isNumeric` should reject for array

[aemzayn]

Describe the bug

The isNumeric should throw the error message for the array but it does not

To Reproduce

See this example code

[
 checkSchema({
    id: {
      in: ['body'],
      exists: {
        errorMessage: 'ID is required',
      },
      isNumeric: {
        errorMessage: 'ID must be a number',
      },
    },
  }),
]

When I send a request with this body:

{
  "id": []
}

It sees the array as a number and then it passes the validation

Expected behavior

IT should reject the request because the value is not a number

Current behavior

IT should reject the request because the value is not a number

Environment:

• Express-validator version: 7.2.0
• Express version: 4.21.2
• Node.js version: 20.15.1

[gustavohenke]

As of today, each of an array's value is checked individually. When there isn't any, that's a pass.
This behaviour is called out in the docs here

[aemzayn]

I see, but what is the best practice if I want only a number, not an array? I think isInt also does the same, otherwise, I will have to add isArray everywhere like this

[
 checkSchema({
    id: {
      in: ['body'],
      exists: {
        errorMessage: 'ID is required',
      },
      isNumeric: {
        errorMessage: 'ID must be a number',
      },
     isArray: {
       negated: true,
       errorMessage: 'ID cannot be array',
     }
    },
  }),
]