[FEATURE] Allow adding attachments to trace

[TannerLarson]

Allow users to add attachments to the playwright trace viewer, similar to how it's done in Node.js

[anupamkr1708]

Hi Tanner Larson (@TannerLarson), I looked through the existing pytest-playwright tracing flow and the corresponding Playwright trace-viewer support. I'd like to take this as a focused contribution and look at how attachments can be exposed through the pytest integration while keeping the existing tracing behavior unchanged.

I’ll first verify the current fixture/lifecycle and the underlying trace attachment support, then I can propose the smallest implementation and test scope. Please let me know if you'd prefer any particular API shape.

[anupamkr1708]

Hi Tanner Larson (@TannerLarson), I dug into the tracing path and found an important limitation before starting implementation.

testInfo.attach() in Node is implemented by the @playwright/test runner itself: it maintains a separate test-trace stream and merges that with the browser trace when the test finishes. The shared Playwright tracing API used by Python doesn't currently expose an equivalent attachment operation.

I also checked playwright-pytest's ArtifactsRecorder: it only starts/stops the browser trace and manages the resulting trace.zip; it has no supported way to inject attachment entries into the trace.

So I don't think this can be implemented cleanly in playwright-pytest alone without depending on Playwright internals. It looks like some upstream support would be needed first. Would you prefer that I track this as an upstream Playwright/Python capability and then revisit the pytest integration once that exists?

[TannerLarson]

Yeah, that would be fine. Full transparency, I've since mostly moved to Node.js directly, so I'm not as keen on this feature any more