Add page.on

[ka3de]

What?

Adds support for page.on method. Currently 'console' event is the only one allowed.

This will allow users to define a function to be executed every time a console API is called in the web page context. Such as:

• console.log
• console.debug
• console.info
• console.error
• console.warn
• console.dir
• console.dirxml
• console.table
• console.trace
• console.clear
• console.assert
• console.profile
• console.profileEnd
• console.group
• console.groupCollapsed
• console.groupEnd
• console.count

See full reference and details at MDN Web Docs for console API.

The handler function defined by the user will receive a console message object as input for every call, such as:

ConsoleMessage {
    args()    // returns the input arguments for the console API method call
    page()   // returns the page that produced this console message
    text()     // returns the text for the console message
    type()    // returns the type for the console message
}

Why?

• Increases the compatibility with Playwright.
• Allows users to perform assertions on console events from the page context execution.

Checklist

• I have performed a self-review of my code
• I have added tests for my changes
• I have commented on my code, particularly in hard-to-understand areas

Related PR(s)/Issue(s)

Updates #835.

[inancgumus]

Excellent work 👏 Thank you for working on this challenging task and delivering it quite remarkably 🙇 I believe we might want to refactor the TaskQueue part later, but it's okay for now.

[ankur22]

This is an awesome feature! Thanks for working on it.

I left some minor comments.

My only concern is around the requirement to need to work with page.close otherwise this is great 🙂 Maybe we can think over another solution or talk it through with k6 to see if they can help.

[ka3de]

Here's a humble suggestion: Instead of this PR closing the issue, would you like to update the documentation before closing the issue?

Right, this was my plan actually @inancgumus, as there are related documentation and TS types tasks that need to be done. I will change the "closes" comment for "updates" 👍

[inancgumus]

One suggestion about documentation and the clarifying the protocol in tests 👍

[ankur22]

LGTM! This is looking great. Thanks for taking the feedback onboard.

[inancgumus]

Awesome work 👏 Thanks for considering our suggestions and applying them nicely!