If a field is hidden, it should NOT be validated

[barmac]

Describe the Bug

Hidden fields are validated even though there is no way to change their values.

Steps to Reproduce

1. Open this form:

{
  "components": [
    {
      "label": "Checkbox",
      "type": "checkbox",
      "layout": {
        "row": "Row_0ifu9f7",
        "columns": null
      },
      "id": "Field_0r8ir96",
      "key": "checkbox_4u82gk"
    },
    {
      "label": "Number",
      "type": "number",
      "layout": {
        "row": "Row_0ifu9f7",
        "columns": null
      },
      "id": "Field_17uk1c9",
      "key": "number_o4f027",
      "conditional": {
        "hide": "=checkbox_4u82gk"
      },
      "validate": {
        "required": true
      }
    },
    {
      "action": "reset",
      "label": "Reset",
      "type": "button",
      "id": "Field_1jcm8tv",
      "layout": {
        "row": "Row_0ifu9f7"
      }
    },
    {
      "action": "submit",
      "label": "Button",
      "type": "button",
      "layout": {
        "row": "Row_15idciq",
        "columns": null
      },
      "id": "Field_0bqqn6m"
    }
  ],
  "type": "default",
  "id": "Form_0k71hbi",
  "exporter": {},
  "schemaVersion": 11
}

2. Tick the checkbox
3. Submit and read the errors
4. Field_17uk1c9 appears in the errors, even though it's hidden.

Expected Behavior

Field should not be validated if it's hidden.

Environment

• Host (Browser/Node version), if applicable: [e.g. MS Edge 18, Chrome 69, Node 10 LTS]
• OS: [e.g. Windows 7]
• Library version: [e.g. 2.0.0]

---

Reported via forums: https://forum.camunda.io/t/required-validation-on-hidden-inputs/47782

[pinussilvestrus]

Thanks for opening! I used your form and tried to reproduce it with the steps you provided. What is interesting is that when using other keys, the behavior works as expected (no errors shown)

In this line we explicitly filter for hidden fields. Maybe there is something not working with the provided key (lower case + special chars)?

[pinussilvestrus]

I added a test case via https://github.com/bpmn-io/form-js/compare/825-errors-hidden-fields?expand=1

[pinussilvestrus]

It seems like this._applyConditions only removes via the value path of the given field, but we reference errors via the ID, which might be the root cause here - and why my example above worked as I used the same key & id.