When coerceTypes is true, custom format function was not executed.

[amazing-gao]

What version of Ajv are you using? Does the issue happen if you use the latest version?

Ajv options object (see https://github.com/epoberezkin/ajv#options):

{
    removeAdditional: 'all',
    coerceTypes: true,
    allErrors: true
}

JSON Schema (please make it as small as possible to reproduce the issue):

{
    "properties": {
      "id": {
        "type": "integer",
        "format": "int32"
      }
    }
  }

Data (please make it as small as posssible to reproduce the issue):

{
    "id": "1234"
}

Your code (please use options, schema and data as variables):

const Ajv = require('ajv');

function foo() {
  const ajv = new Ajv({
    removeAdditional: 'all',
    coerceTypes: true,
    allErrors: true
  });

  ajv.addFormat('int32', (data)=> {
    data = Number(data);
    console.log('foo int32 ', data)

    if (data <= 2147483647 && data >= -2147483647)
      return true;
    else
      return false;
  });

  const schema = {
    "properties": {
      "id": {
        "type": "integer",
        "format": "int32"
      }
    }
  }

  const data = {
    id: '1234'
  }

  var validate = ajv.compile(schema);
  var ret = validate(data);
  console.log(ret, data, validate.errors);
}

foo();

Validation result, data AFTER validation, error messages:

// console.log output
true { id: 1234 } null

What results did you expect?
valid and int32 format function was executed.
but int32 custom function was not executed.

Are you going to resolve the issue?
At this moment, I don't know how to resolve it.

[epoberezkin]

At the moment, formats only apply to strings, not to any other data type.
Coercion happens when the type is checked, before applying any other keywords, so the data becomes a number and format keyword is not applied.
There is a feature #291 to support format for all datatypes that I agreed to include - @nimerritt was going to create a PR - are you still?

[nimerritt]

@epoberezkin Yes, I mostly finished it last weekend but need to figure out how to support type detection in the format-rule, when there is no type declaration. I'll push what I have tomorrow and may need to tag you for a tip if I can't figure it out.