{
  "description": "group-accumulators",
  "schemaVersion": "1.4",
  "createEntities": [
    {
      "client": {
        "id": "client0"
      }
    },
    {
      "database": {
        "id": "database0",
        "client": "client0",
        "databaseName": "aggregate-corpus"
      }
    },
    {
      "collection": {
        "id": "collection0",
        "database": "database0",
        "collectionName": "coll"
      }
    }
  ],
  "initialData": [
    {
      "collectionName": "coll",
      "databaseName": "aggregate-corpus",
      "documents": [
        {
          "_id": 1,
          "g": "a",
          "x": 10,
          "s": "p",
          "t": [
            1,
            2
          ]
        },
        {
          "_id": 2,
          "g": "a",
          "x": 20,
          "s": "q",
          "t": [
            2,
            3
          ]
        },
        {
          "_id": 3,
          "g": "b",
          "x": 30,
          "s": "p",
          "t": []
        },
        {
          "_id": 4,
          "g": "b",
          "x": 7,
          "s": "r"
        },
        {
          "_id": 5,
          "g": "b",
          "x": "not a number",
          "s": "p",
          "t": [
            4
          ]
        }
      ]
    }
  ],
  "tests": [
    {
      "description": "$sum over a field path",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$g",
                  "v": {
                    "$sum": "$x"
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "a",
              "v": 30
            },
            {
              "_id": "b",
              "v": 37
            }
          ]
        }
      ]
    },
    {
      "description": "$sum counts with a constant",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$g",
                  "v": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "a",
              "v": 2
            },
            {
              "_id": "b",
              "v": 3
            }
          ]
        }
      ]
    },
    {
      "description": "$avg ignores non-numeric values",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$g",
                  "v": {
                    "$avg": "$x"
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "a",
              "v": 15
            },
            {
              "_id": "b",
              "v": 18.5
            }
          ]
        }
      ]
    },
    {
      "description": "$avg of a group with no numeric value at all",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$s",
                  "v": {
                    "$avg": "$missing"
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "p",
              "v": null
            },
            {
              "_id": "q",
              "v": null
            },
            {
              "_id": "r",
              "v": null
            }
          ]
        }
      ]
    },
    {
      "description": "$min and $max compare across types",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$g",
                  "lo": {
                    "$min": "$x"
                  },
                  "hi": {
                    "$max": "$x"
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "a",
              "lo": 10,
              "hi": 20
            },
            {
              "_id": "b",
              "lo": 7,
              "hi": "not a number"
            }
          ]
        }
      ]
    },
    {
      "description": "$min of a field no document has",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$g",
                  "v": {
                    "$min": "$missing"
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "a",
              "v": null
            },
            {
              "_id": "b",
              "v": null
            }
          ]
        }
      ]
    },
    {
      "description": "$first and $last follow the input order",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$sort": {
                  "_id": 1
                }
              },
              {
                "$group": {
                  "_id": "$g",
                  "f": {
                    "$first": "$x"
                  },
                  "l": {
                    "$last": "$x"
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "a",
              "f": 10,
              "l": 20
            },
            {
              "_id": "b",
              "f": 30,
              "l": "not a number"
            }
          ]
        }
      ]
    },
    {
      "description": "$push keeps duplicates and order",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$sort": {
                  "_id": 1
                }
              },
              {
                "$group": {
                  "_id": "$s",
                  "v": {
                    "$push": "$g"
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "p",
              "v": [
                "a",
                "b",
                "b"
              ]
            },
            {
              "_id": "q",
              "v": [
                "a"
              ]
            },
            {
              "_id": "r",
              "v": [
                "b"
              ]
            }
          ]
        }
      ]
    },
    {
      "description": "$push of a missing field skips it",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$sort": {
                  "_id": 1
                }
              },
              {
                "$group": {
                  "_id": "$g",
                  "v": {
                    "$push": "$t"
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "a",
              "v": [
                [
                  1,
                  2
                ],
                [
                  2,
                  3
                ]
              ]
            },
            {
              "_id": "b",
              "v": [
                [],
                [
                  4
                ]
              ]
            }
          ]
        }
      ]
    },
    {
      "description": "$addToSet drops duplicates",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$s",
                  "v": {
                    "$addToSet": "$g"
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "p",
              "v": [
                "a",
                "b"
              ]
            },
            {
              "_id": "q",
              "v": [
                "a"
              ]
            },
            {
              "_id": "r",
              "v": [
                "b"
              ]
            }
          ]
        }
      ]
    },
    {
      "description": "$count is the number of documents in the group",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$g",
                  "v": {
                    "$count": {}
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "a",
              "v": 2
            },
            {
              "_id": "b",
              "v": 3
            }
          ]
        }
      ]
    },
    {
      "description": "a compound _id groups on every field",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "g": "$g",
                    "s": "$s"
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id.g": 1,
                  "_id.s": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": {
                "g": "a",
                "s": "p"
              },
              "n": 1
            },
            {
              "_id": {
                "g": "a",
                "s": "q"
              },
              "n": 1
            },
            {
              "_id": {
                "g": "b",
                "s": "p"
              },
              "n": 2
            },
            {
              "_id": {
                "g": "b",
                "s": "r"
              },
              "n": 1
            }
          ]
        }
      ]
    },
    {
      "description": "a constant _id puts everything in one group",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": null,
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": null,
              "n": 5
            }
          ]
        }
      ]
    },
    {
      "description": "an _id path that no document has",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$missing",
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": null,
              "n": 5
            }
          ]
        }
      ]
    },
    {
      "description": "grouping on an array field",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$t",
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": null,
              "n": 1
            },
            {
              "_id": [],
              "n": 1
            },
            {
              "_id": [
                1,
                2
              ],
              "n": 1
            },
            {
              "_id": [
                2,
                3
              ],
              "n": 1
            },
            {
              "_id": [
                4
              ],
              "n": 1
            }
          ]
        }
      ]
    },
    {
      "description": "an unknown accumulator is refused",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$g",
                  "v": {
                    "$bogusAcc": "$x"
                  }
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 15952
          }
        }
      ]
    },
    {
      "description": "an accumulator that is not a document is refused",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$g",
                  "v": "$x"
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 40234
          }
        }
      ]
    },
    {
      "description": "two accumulators in one field are refused",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$g",
                  "v": {
                    "$sum": "$x",
                    "$max": "$x"
                  }
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 40238
          }
        }
      ]
    },
    {
      "description": "a $group without _id is refused",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 15955
          }
        }
      ]
    }
  ]
}