Function matchesKeyConstraints

src/LiveQuery/QueryTools.js:203–451

* Determines whether an object matches a single key's constraints

(object, key, constraints)

 * Determines whether an object matches a single key's constraints
 */
function matchesKeyConstraints(object, key, constraints) {
  if (constraints === null) {
    return false;
  }
  if (key.indexOf('.') >= 0) {
    // Key references a subobject
    var keyComponents = key.split('.');
    var subObjectKey = keyComponents[0];
    var keyRemainder = keyComponents.slice(1).join('.');
    return matchesKeyConstraints(object[subObjectKey] || {}, keyRemainder, constraints);
  }
  var i;
  if (key === '$or') {
    if (!Array.isArray(constraints)) {
      return false;
    }
    for (i = 0; i < constraints.length; i++) {
      if (matchesQuery(object, constraints[i])) {
        return true;
      }
    }
    return false;
  }
  if (key === '$and') {
    if (!Array.isArray(constraints)) {
      return false;
    }
    for (i = 0; i < constraints.length; i++) {
      if (!matchesQuery(object, constraints[i])) {
        return false;
      }
    }
    return true;
  }
  if (key === '$nor') {
    if (!Array.isArray(constraints)) {
      return false;
    }
    for (i = 0; i < constraints.length; i++) {
      if (matchesQuery(object, constraints[i])) {
        return false;
      }
    }
    return true;
  }
  if (key === '$relatedTo') {
    // Bail! We can't handle relational queries locally
    return false;
  }
  // Decode Date JSON value
  if (object[key] && object[key].__type == 'Date') {
    object[key] = new Date(object[key].iso);
  }
  // Equality (or Array contains) cases
  if (typeof constraints !== 'object') {
    if (Array.isArray(object[key])) {
      return object[key].indexOf(constraints) > -1;
    }