Function validateExplicitKey

docs/lib/react.js:10237–10249

* Warn if the element doesn't have an explicit key assigned to it. * This element is in an array. The array could grow and shrink or be * reordered. All children that haven't already been validated are required to * have a "key" property assigned to it. * * @internal * @param {ReactElement} el

(element, parentType)

 * @param {*} parentType element's parent's type.
 */
function validateExplicitKey(element, parentType) {
  if (!element._store || element._store.validated || element.key != null) {
    return;
  }
  element._store.validated = true;

  var addenda = getAddendaForKeyUse('uniqueKey', element, parentType);
  if (addenda === null) {
    // we already showed the warning
    return;
  }
  "development" !== 'production' ? warning(false, 'Each child in an array or iterator should have a unique "key" prop.' + '%s%s%s', addenda.parentOrOwner || '', addenda.childOwner || '', addenda.url || '') : void 0;
}

/**
 * Shared warning and monitoring code for the key warnings.