Need a way to click without any JS code on the stack

[domenic]

In writing the tests in #14157, I need to trigger clicks. However, I need to trigger them specifically like a user does, with no JavaScript code on the stack.

I'm unclear from the documentation whether that's possible. I can't figure out how to run my Chrome install in "testdriver mode" to figure it out myself. And, @gsnedders indicated in whatwg/html#4181 (comment) it might not be possible anyway. So, I want to open this issue to discuss.

For now I've made my tests -manual.html, but it would be great to automate them.

[gsnedders]

@foolip @Hexcles do you know if there's any way to do this currently in Blink, or would this potentially be adding something to testdriver.js that can't be immediately implemented in Blink's runner?

[foolip]

With test_driver.click() backed by WebDriver there would already be no JS code on the stack. Maybe we can just add a test in infrastructure/ verifying that it is so, and eventually finding a way to support it in Blink too? It would become possible if @LukeZielinski's investigations into ./wpt run in Chromium pan out, or if we control content_shell using WebDriver/CDP in some other manner.

[Hexcles]

IIUC, test_driver.click() doesn't create a new stack frame because the function simply posts a message and then return; the parent window receives the message and asks WebDriver to click? Whereas the Blink internal API is a blocking JS call?

[foolip]

That's right.