{
  "description": "expressions",
  "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,
          "a": 10,
          "b": 3,
          "s": "x",
          "n": null,
          "f": false
        },
        {
          "_id": 2,
          "a": 20,
          "b": 0,
          "s": "y",
          "f": true
        },
        {
          "_id": 3,
          "a": -5,
          "b": 4,
          "s": "x",
          "n": 7,
          "f": false
        }
      ]
    }
  ],
  "tests": [
    {
      "description": "a compound _id groups on every field",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "s": "$s",
                    "f": "$f"
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id.s": 1,
                  "_id.f": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": {
                "s": "x",
                "f": false
              },
              "n": 2
            },
            {
              "_id": {
                "s": "y",
                "f": true
              },
              "n": 1
            }
          ]
        }
      ]
    },
    {
      "description": "a nested compound _id",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "outer": {
                      "inner": "$s"
                    }
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id.outer.inner": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": {
                "outer": {
                  "inner": "x"
                }
              },
              "n": 2
            },
            {
              "_id": {
                "outer": {
                  "inner": "y"
                }
              },
              "n": 1
            }
          ]
        }
      ]
    },
    {
      "description": "$literal keeps a $-string from being a path",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$literal": "$s"
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "$s",
              "n": 3
            }
          ]
        }
      ]
    },
    {
      "description": "$literal of a document",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$literal": {
                      "$sum": 1
                    }
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": {
                "$sum": 1
              },
              "n": 3
            }
          ]
        }
      ]
    },
    {
      "description": "$add of a path and a constant",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$add": [
                      "$a",
                      1
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": -4,
              "n": 1
            },
            {
              "_id": 11,
              "n": 1
            },
            {
              "_id": 21,
              "n": 1
            }
          ]
        }
      ]
    },
    {
      "description": "$subtract and $multiply",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$s",
                  "d": {
                    "$sum": {
                      "$subtract": [
                        "$a",
                        "$b"
                      ]
                    }
                  },
                  "m": {
                    "$sum": {
                      "$multiply": [
                        "$a",
                        2
                      ]
                    }
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "x",
              "d": -2,
              "m": 10
            },
            {
              "_id": "y",
              "d": 20,
              "m": 40
            }
          ]
        }
      ]
    },
    {
      "description": "$divide by zero is an error",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": null,
                  "v": {
                    "$sum": {
                      "$divide": [
                        "$a",
                        "$b"
                      ]
                    }
                  }
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 4848401
          }
        }
      ]
    },
    {
      "description": "$divide and $mod",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$match": {
                  "b": {
                    "$gt": 0
                  }
                }
              },
              {
                "$group": {
                  "_id": "$s",
                  "d": {
                    "$push": {
                      "$divide": [
                        "$a",
                        "$b"
                      ]
                    }
                  },
                  "m": {
                    "$push": {
                      "$mod": [
                        "$a",
                        "$b"
                      ]
                    }
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "x",
              "d": [
                3.3333333333333335,
                -1.25
              ],
              "m": [
                1,
                -1
              ]
            }
          ]
        }
      ]
    },
    {
      "description": "arithmetic over a missing field",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$add": [
                      "$missing",
                      1
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": null,
              "n": 3
            }
          ]
        }
      ]
    },
    {
      "description": "arithmetic over null",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$s",
                  "v": {
                    "$push": {
                      "$add": [
                        "$n",
                        1
                      ]
                    }
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "x",
              "v": [
                null,
                8
              ]
            },
            {
              "_id": "y",
              "v": [
                null
              ]
            }
          ]
        }
      ]
    },
    {
      "description": "$eq and $ne",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$eq": [
                      "$s",
                      "x"
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": false,
              "n": 1
            },
            {
              "_id": true,
              "n": 2
            }
          ]
        }
      ]
    },
    {
      "description": "comparison across types follows canonical order",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$lt": [
                      "$a",
                      "$s"
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": true,
              "n": 3
            }
          ]
        }
      ]
    },
    {
      "description": "$cmp returns the ordering",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": "$s",
                  "v": {
                    "$push": {
                      "$cmp": [
                        "$a",
                        "$b"
                      ]
                    }
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "x",
              "v": [
                1,
                -1
              ]
            },
            {
              "_id": "y",
              "v": [
                1
              ]
            }
          ]
        }
      ]
    },
    {
      "description": "$and and $or are truthy over non-booleans",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$and": [
                      "$a",
                      "$f"
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": false,
              "n": 2
            },
            {
              "_id": true,
              "n": 1
            }
          ]
        }
      ]
    },
    {
      "description": "$not of a missing field",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$not": [
                      "$missing"
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": true,
              "n": 3
            }
          ]
        }
      ]
    },
    {
      "description": "$cond in its array form",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$cond": [
                      {
                        "$gt": [
                          "$a",
                          0
                        ]
                      },
                      "positive",
                      "negative"
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "negative",
              "n": 1
            },
            {
              "_id": "positive",
              "n": 2
            }
          ]
        }
      ]
    },
    {
      "description": "$cond in its document form",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$cond": {
                      "if": "$f",
                      "then": "yes",
                      "else": "no"
                    }
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "no",
              "n": 2
            },
            {
              "_id": "yes",
              "n": 1
            }
          ]
        }
      ]
    },
    {
      "description": "$ifNull falls through on missing and on null",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$ifNull": [
                      "$n",
                      "fallback"
                    ]
                  },
                  "count": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": 7,
              "count": 1
            },
            {
              "_id": "fallback",
              "count": 2
            }
          ]
        }
      ]
    },
    {
      "description": "$switch picks the first matching branch",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$switch": {
                      "branches": [
                        {
                          "case": {
                            "$lt": [
                              "$a",
                              0
                            ]
                          },
                          "then": "neg"
                        },
                        {
                          "case": {
                            "$lt": [
                              "$a",
                              15
                            ]
                          },
                          "then": "small"
                        }
                      ],
                      "default": "big"
                    }
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": "big",
              "n": 1
            },
            {
              "_id": "neg",
              "n": 1
            },
            {
              "_id": "small",
              "n": 1
            }
          ]
        }
      ]
    },
    {
      "description": "$switch with no branch matching and no default is an error",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$switch": {
                      "branches": [
                        {
                          "case": false,
                          "then": "never"
                        }
                      ]
                    }
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 40069
          }
        }
      ]
    },
    {
      "description": "an unknown expression operator is refused",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$bogusExpr": "$a"
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 168
          }
        }
      ]
    },
    {
      "description": "two operators in one expression document are refused",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$add": [
                      "$a",
                      1
                    ],
                    "$literal": 2
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 15983
          }
        }
      ]
    },
    {
      "description": "a nested expression inside an accumulator argument",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": null,
                  "v": {
                    "$max": {
                      "$add": [
                        {
                          "$multiply": [
                            "$a",
                            2
                          ]
                        },
                        "$b"
                      ]
                    }
                  }
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": null,
              "v": 40
            }
          ]
        }
      ]
    },
    {
      "description": "arithmetic over a non-numeric value is an error",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$add": [
                      "$s",
                      1
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 7157723
          }
        }
      ]
    },
    {
      "description": "$not takes a bare argument as well as an array",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$not": "$f"
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": false,
              "n": 1
            },
            {
              "_id": true,
              "n": 2
            }
          ]
        }
      ]
    },
    {
      "description": "$add of several operands",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$add": [
                      "$a",
                      "$b",
                      100
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              },
              {
                "$sort": {
                  "_id": 1
                }
              }
            ]
          },
          "expectResult": [
            {
              "_id": 99,
              "n": 1
            },
            {
              "_id": 113,
              "n": 1
            },
            {
              "_id": 120,
              "n": 1
            }
          ]
        }
      ]
    },
    {
      "description": "$subtract needs exactly two operands",
      "operations": [
        {
          "object": "collection0",
          "name": "aggregate",
          "arguments": {
            "pipeline": [
              {
                "$group": {
                  "_id": {
                    "$subtract": [
                      "$a"
                    ]
                  },
                  "n": {
                    "$sum": 1
                  }
                }
              }
            ]
          },
          "expectError": {
            "isError": true,
            "errorCode": 16020
          }
        }
      ]
    }
  ]
}