date field types fail to index specific malformed data even with ignore_malformed enabled

[lkts]

Elasticsearch Version

8.14

Installed Plugins

No response

Java Version

bundled

OS Version

Problem Description

As noticed in #109410 if a value of date or date_nanos field is an object, indexing such value will fail even with ignore_malformed enabled. This behavior differs from other field types like numbers.

Steps to Reproduce

PUT /my_index
{
  "mappings": {
      "properties": {
          "date": {
              "type": "date",
              "ignore_malformed": true
          }
        }
    }
  }
}

// OK
PUT my_index/_doc/1
{
  "date": "hello"
}

// Fails
PUT my_index/_doc/2
{
  "date": {"string": "hello"}
}

Logs (if relevant)

No response

[elasticsearchmachine]

Pinging @elastic/es-storage-engine (Team:StorageEngine)

[martijnvg]

@lkts This is fixed for that #109410 is merged, right?

[lkts]

No, that PR does not fix it. The actual logic of ignore_malformed is not changed.