Queries on relation fields with multiple ins do not work correctly. #1271

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Steps to reproduce

• See "queries on relation fields with multiple ins" case in ParseRelation.spec.js

  • The expected number of results must be zero not two. The case is incorrect.

  it("queries on relation fields with multiple ins", (done) => {
      var ChildObject = Parse.Object.extend("ChildObject");
      var childObjects = [];
      for (var i = 0; i < 10; i++) {
        childObjects.push(new ChildObject({x: i}));
      }
  
      Parse.Object.saveAll(childObjects).then(() => {
        var ParentObject = Parse.Object.extend("ParentObject");
        var parent = new ParentObject();
        parent.set("x", 4);
        var relation = parent.relation("child");
        relation.add(childObjects[0]);
        relation.add(childObjects[1]);
        relation.add(childObjects[2]);
        var parent2 = new ParentObject();
        parent2.set("x", 3);
        var relation2 = parent2.relation("child");
        relation2.add(childObjects[4]);
        relation2.add(childObjects[5]);
        relation2.add(childObjects[6]);
  
        var otherChild2 = parent2.relation("otherChild");
        otherChild2.add(childObjects[0]);
        otherChild2.add(childObjects[1]);
        otherChild2.add(childObjects[2]);
  
        var parents = [];
        parents.push(parent);
        parents.push(parent2);
        return Parse.Object.saveAll(parents);
      }).then(() => {
        var query = new Parse.Query(ParentObject);
        var objects = [];
        objects.push(childObjects[0]);
        query.containedIn("child", objects);
        query.containedIn("otherChild", [childObjects[0]]);
        return query.find();
      }).then((list) => {
        equal(list.length, 2, "There should be 2 results");
        done();
      });
    });

Logs/Trace

• The actual REST request generated by the case

  {
    "where": {
      "child": {
        "$in": [
          {
            "__type": "Pointer",
            "className": "ChildObject",
            "objectId": "t4EmF6vnq5"
          }
        ]
      },
      "otherChild": {
        "$in": [
          {
            "__type": "Pointer",
            "className": "ChildObject",
            "objectId": "t4EmF6vnq5"
          }
        ]
      }
    },
    "_method": "GET"
  }

Causes

DatabaseController.prototype.addInObjectIdsIds = function(ids, query) {
  if (typeof query.objectId == 'string') {
    // Add equality op as we are sure
    // we had a constraint on that one
    query.objectId = {'$eq': query.objectId};
  }
  query.objectId = query.objectId || {};
  let queryIn =  [].concat(query.objectId['$in'] || [], ids || []);
  // make a set and spread to remove duplicates
  // replace the $in operator as other constraints
  // may be set
  query.objectId['$in'] = [...new Set(queryIn)];

  return query;
}

• multiple $ins on different relation fields end up having a merged $in on objectId

  {
    "child": {
      "$in": [
        "pointer to child0"
      ]
    },
    "otherChild": {
      "$in": [
        "pointer to child0"
      ]
    }
  }

  becomes

  {
    "objectId": {
      "$in": [
        "objectId of parent",
        "objectId of parent2"
      ]
    }
  }

  It is supposed to be like

  {
    "$and": [
      {
        "objectId": {
          "$in": [
            "objectId of parent"
          ]
        }
      },
      {
        "objectId": {
          "$in": [
            "objectId of parent2"
          ]
        }
      }
    ]
  }