Function hydrateInput

packages/react-dom-bindings/src/client/ReactDOMInput.js:347–381

(
  element: Element,
  value: ?string,
  defaultValue: ?string,
  checked: ?boolean,
  defaultChecked: ?boolean,
)

}

export function hydrateInput(
  element: Element,
  value: ?string,
  defaultValue: ?string,
  checked: ?boolean,
  defaultChecked: ?boolean,
): void {
  const node: HTMLInputElement = (element: any);

  const defaultValueStr =
    defaultValue != null ? toString(getToStringValue(defaultValue)) : '';
  const initialValue =
    value != null ? toString(getToStringValue(value)) : defaultValueStr;

  const checkedOrDefault = checked != null ? checked : defaultChecked;
  // TODO: This 'function' or 'symbol' check isn't replicated in other places
  // so this semantic is inconsistent.
  const initialChecked =
    typeof checkedOrDefault !== 'function' &&
    typeof checkedOrDefault !== 'symbol' &&
    !!checkedOrDefault;

  // Detach .checked from .defaultChecked but leave user input alone
  node.checked = node.checked;

  const changed = trackHydrated((node: any), initialValue, initialChecked);
  if (changed) {
    // If the current value is different, that suggests that the user
    // changed it before hydration. Queue a replay of the change event.
    // For radio buttons the change event only fires on the selected one.
    if (node.type !== 'radio' || node.checked) {
      queueChangeEvent(node);
    }
  }
}

export function restoreControlledInputState(element: Element, props: Object) {
  const rootNode: HTMLInputElement = (element: any);