minecraft-assets/data/minecraft/worldgen/placed_feature/spruce_checked.json

{
  "feature": "minecraft:spruce",
  "placement": [
    {
      "type": "minecraft:block_predicate_filter",
      "predicate": {
        "type": "minecraft:would_survive",
        "state": {
          "Name": "minecraft:spruce_sapling",
          "Properties": {
            "stage": "0"
          }
        }
      }
    }
  ]
}