Boxplot set null quantitative to 0

[yhoonkim]

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": {
    "values": [
      {"C": "A", "X": 1, "Y": 0.7},
      {"C": "A", "X": 1.5, "Y": 0.7},
      {"C": "A", "X": null, "Y": 0.7},
      {"C": "B", "X": 1, "Y": 1.7},
      {"C": "B", "X": 1.5, "Y": 1.7},
      {"C": "B", "X": null, "Y": 1.7},
      {"C": "C", "X": 1, "Y": 2.7},
      {"C": "C", "X": 1.5, "Y": 2.7},
      {"C": "C", "X": null, "Y": 2.7}
    ]
  },
  "mark": "boxplot",
  "encoding": {
    "x": {"field": "X", "type": "quantitative"},
    "y": {"field": "Y", "type": "quantitative"}
  }
}

Suggestion:
The null box should be filtered out as when the box with null "Y" are filtered out:

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": {
    "values": [
      {"C": "A", "X": 1, "Y": 0.7},
      {"C": "A", "X": 1.5, "Y": 0.7},
      {"C": "A", "X": 2, "Y": null},
      {"C": "B", "X": 1, "Y": 1.7},
      {"C": "B", "X": 1.5, "Y": 1.7},
      {"C": "B", "X": 2, "Y": null},
      {"C": "C", "X": 1, "Y": 2.7},
      {"C": "C", "X": 1.5, "Y": 2.7},
      {"C": "C", "X": 2, "Y": null}
    ]
  },
  "mark": "boxplot",
  "encoding": {
    "x": {"field": "X", "type": "quantitative"},
    "y": {"field": "Y", "type": "quantitative"}
  }
}

[kanitw]

Yeah we should make boxplot respect mark.invalid

• If mark.invalid is null the current behavior is correct.
• If mark.invalid is filter (default), we should filter. (But right now filter isn't respected at all.)