[Feature]: Please do not cast Locator to LocatorImpl.

[RichMacDonald]

🚀 Feature Request

https://github.com/microsoft/playwright-java/blob/main/playwright/src/main/java/com/microsoft/playwright/impl/LocatorAssertionsImpl.java

The following method:

  private LocatorAssertionsImpl(Locator locator, boolean isNot) {
    super(isNot);
    this.actualLocator = (LocatorImpl) locator;
  }

casts Locator to a LocatorImpl. This breaks the purpose of an interface. There may be other implementations of Locator and this causes a cast exception.

For example, I use the Delegate pattern to wrap a Playwright Locator with my own Locator. This lets me add some extra methods that I like to use (syntactical sugar). It also lets me write code that doesn't need to know if it is dealing with a Page or Locator.

Example

No response

Motivation

It is code smell to cast an interface to a class. It also prevents anyone else from providing a different implementation. In many organizations, this will be classified as a bug.

Wrapping the Locator interface with a LocatorDelegate implementation lets me add some convenience methods that I use in my code. Methods that I find useful but the playwright developers feel differently about. For example, I could never remember how to execute "Tab" so I wrote a method in my LocatorDelegate:

public Locator pressTab() {
	page().keyboard().press("Tab");
	return this;
}

I also find the distinction between Page and Locator a little awkward. My LocatorDelegate can hide from a user the fact that we are referencing a Page or a Locator (make the Page act like a Locator).

The unfortunate cast does not break my code. I can always "dereference the delegate" before calling PlaywrightAssertions.assertThat(locator);.