[BUG] locator.count: Error while parsing selector ":nth-last-child(1 of ...) ~ *"

[goodwin64]

Maybe it's not the bug but not yet supported selector by Playwright so sorry in advance 🙏
I skimmed through the Stack Overflow and a couple of articles but couldn't find a similar issue.

System info

• Playwright Version: [v1.XX] - default in playground
• Operating System: [All, Windows 11, Ubuntu 20, macOS 13.2, etc.] - MacOS 14, but ran in the playground
• Browser: [All, Chromium, Firefox, WebKit] - Chrome
• Other info:

Source code

• I provided exact source code that allows reproducing the issue locally.

Link to the test file

https://try.playwright.tech/?l=javascript&s=khc2kb8

Link to the JSFiddle with CSS selector usage
https://jsfiddle.net/654t7skb/9/

Steps

• Open the JSFiddle, see that selector successfully highlights some elements
• Run the Playwright playground file, see that it throws an error after being unable to parse that selector

Expected

nth-last-child( ) selector is supported

Actual

nth-last-child( ) selector is NOT supported

[goodwin64]

Workaround I used instead:

// not working:
const nextElementsCount = await page
  .locator(':nth-last-child(1 of .Checkpoints:has(.Checkpoints_span).CheckpointCurrent2_Sign) ~ *')
  .count();

// working:
const nextElementsCount = await page.evaluate(
    () =>
      [
        ...document.querySelectorAll(
          ':nth-last-child(1 of .Checkpoints:has(.Checkpoints_span).CheckpointCurrent2_Sign) ~ *'
        ),
      ].length
  );

[goodwin64]

Thank you! 🚀