{
  "_comment": [
    "Inputs only. Expectations are measured -- see record.js.",
    "`$push`'s modifiers: `$each`, `$slice`, `$position`, `$sort`. This server",
    "already implements `$push` and `$each` and *silently ignores* the other",
    "three -- `{$each: [3, 4], $slice: -3}` appended and did not slice, and",
    "answered ok: 1. That is the same class of wrong answer the positional",
    "operators were: the client asked for one thing and was told it got it."
  ],
  "documents": [{ "_id": 1, "t": [1, 2] }],
  "cases": [
    {
      "description": "$slice keeps the last n",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [3, 4], "$slice": -3 } } } }
    },
    {
      "description": "$slice keeps the first n",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [3, 4], "$slice": 3 } } } }
    },
    {
      "description": "$slice of zero empties the array",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [3], "$slice": 0 } } } }
    },
    {
      "description": "$slice larger than the array keeps all of it",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [3], "$slice": 10 } } } }
    },
    {
      "description": "$slice with an empty $each truncates without adding",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [], "$slice": 1 } } } }
    },
    {
      "description": "$position inserts at the front",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [9], "$position": 0 } } } }
    },
    {
      "description": "$position inserts in the middle",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [9], "$position": 1 } } } }
    },
    {
      "description": "$position past the end appends",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [9], "$position": 99 } } } }
    },
    {
      "description": "$position counted from the end",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [9], "$position": -1 } } } }
    },
    {
      "description": "$sort ascending over scalars",
      "documents": [{ "_id": 1, "t": [3, 1] }],
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [2], "$sort": 1 } } } }
    },
    {
      "description": "$sort descending over scalars",
      "documents": [{ "_id": 1, "t": [3, 1] }],
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [2], "$sort": -1 } } } }
    },
    {
      "description": "$sort on a field of the elements",
      "documents": [{ "_id": 1, "t": [{ "a": 3 }, { "a": 1 }] }],
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [{ "a": 2 }], "$sort": { "a": 1 } } } } }
    },
    {
      "description": "$sort and $slice together",
      "documents": [{ "_id": 1, "t": [3, 1] }],
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [2], "$sort": 1, "$slice": 2 } } } }
    },
    {
      "description": "$position and $slice together",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [9], "$position": 0, "$slice": 2 } } } }
    },
    {
      "description": "$slice without $each",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$slice": 1 } } } }
    },
    {
      "description": "$each that is not an array",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": 3 } } } }
    },
    {
      "description": "$slice that is not a number",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [3], "$slice": "x" } } } }
    },
    {
      "description": "$position that is not a number",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [3], "$position": "x" } } } }
    },
    {
      "description": "an unknown modifier beside $each",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "$each": [3], "$bogus": 1 } } } }
    },
    {
      "description": "a document operand that is not modifiers at all is a value",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "t": { "a": 1 } } } }
    },
    {
      "description": "$push $each onto a missing field",
      "operation": "updateOne",
      "arguments": { "filter": {}, "update": { "$push": { "gone": { "$each": [1, 2] } } } }
    }
  ]
}