feat: CORS iframes + closed shadow DOM parity#226
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…arity Brings the same helper surface used by percy-nightwatch / percy-webdriverio into percy-selenium-python directly: DEFAULT_MAX_FRAME_DEPTH, clamp_frame_depth, normalize_ignore_selectors, is_unsupported_iframe_src, get_origin, resolve_max_frame_depth, resolve_ignore_selectors, and the PercyContextLost exception. No SDK version bump — Python doesn't share a utils package with the JS SDKs, so the helpers ship inline. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Implements feature parity with percy-nightwatch / percy-webdriverio for cross-origin iframe serialization: - Replaces the flat single-level iframe scan with a recursive ``process_frame_tree`` walk bounded by ``DEFAULT_MAX_FRAME_DEPTH`` (5, overridable via ``maxIframeDepth`` option or ``percy.config.snapshot.maxIframeDepth``). - Adds an ancestor-URL cycle guard so frames that link back to a previously-visited URL stop descending instead of recursing forever. - Adds an ``enumerate_iframes_script`` JS helper that runs inside the current frame context and returns metadata for every iframe (src, srcdoc, percyElementId, dataPercyIgnore, matchesIgnoreSelector, index). Nested-frame discovery now uses this script in the child context so nested-frame origin comparisons are against the *immediate* parent origin, not the page origin. - ``data-percy-ignore`` attribute opt-out: any iframe with this attribute is dropped before any switch. - ``ignoreIframeSelectors`` option (and ``ignore_iframe_selectors`` / ``percy.config.snapshot.ignoreIframeSelectors``): selectors are baked into the in-browser enumeration script so matching iframes are dropped before being processed. - Post-switch URL re-check via ``is_unsupported_iframe_src``: after switching into a frame we read ``document.URL`` and bail if the loaded document is about:blank, about:srcdoc, a net-error page, or another unsupported scheme. - ``PercyContextLost`` recovery: if ``switch_to.parent_frame()`` fails at depth > 1 we raise ``PercyContextLost`` carrying the ``partial_capture`` collected so far. The top-level walk merges that partial capture into the final ``corsIframes`` payload before aborting sibling iteration (whose enumeration was performed in a now-lost context). All per-frame serialize calls force ``enableJavaScript=True`` to bypass the standard iframe inlining path inside PercyDOM. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds ``expose_closed_shadow_roots`` (mirrored from percy-playwright's ``exposeClosedShadowRoots``) so that PercyDOM.serialize can capture closed-mode shadow DOM that ordinary DOM traversal cannot reach. Flow: 1. ``DOM.enable`` — gates non-Chromium drivers silently (Firefox/WebKit will fail this call and we no-op without touching the page). 2. ``DOM.getDocument`` with ``depth=-1, pierce=True`` — walks the full DOM tree including every shadow root. 3. Recurse the tree, collecting (host, shadowRoot) backend-node pairs for each ``shadowRootType=='closed'`` entry. Subtrees inside an iframe's ``contentDocument`` are skipped — their JS execution contexts can't see the page's WeakMap. 4. Create ``window.__percyClosedShadowRoots`` (same key PercyDOM uses). 5. For each pair, ``DOM.resolveNode`` both ends, then ``Runtime.callFunctionOn`` to stash the shadow root in the WeakMap keyed by its host element. Wired into ``percy_snapshot`` immediately after PercyDOM injection and re-primed after ``driver.refresh()`` inside ``capture_responsive_dom`` (the WeakMap is destroyed on navigation). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
capture_responsive_dom was unconditionally writing output_file.json to the user's CWD on every snapshot, polluting CI workspaces. Only dump when PERCY_DEBUG is set, and swallow IO errors so a read-only CWD doesn't break capture. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The exact 3.10.3 patch isn't on the actions/setup-python@v6 cache that the GitHub Automatic Dependency Submission workflow uses, so submit-pypi fails on resolution. Pinning to the 3.10 line resolves to the latest cached 3.10.x without affecting our test matrix (test.yml passes python-version explicitly). Mirrors the fix applied to percy-playwright-python. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
A pure-srcdoc iframe has no src attribute. The previous ordering ran the unsupported-src branch first, so pure-srcdoc iframes were silently logged as "unsupported src" instead of being routed through the srcdoc-specific branch (which is the path that downstream consumers / parity tests rely on). Reorder so srcdoc is checked first; an iframe carrying both srcdoc and a real src still takes the srcdoc path because srcdoc wins by spec. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The cycle guard at the top of process_frame_tree only compared iframe_meta['src'] (the static, pre-switch attribute) against ancestor_urls which was seeded with page_url (the post-resolution URL). For a redirect chain — src=A loads B via 30x; B carries src=A — the inner B never matched "A" in ancestors so the cycle wasn't caught until the second hop wasted a full serialize+enumerate round-trip. Add the resolved post-switch document.URL to the comparison so the cycle trips on whichever form happens to match the ancestor chain. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The broad-except at the bottom of process_frame_tree was logging every failure at debug, including top-level (depth==1) failures. That meant a user-visible iframe silently going missing produced zero visible output unless PERCY_LOGLEVEL=debug — exactly the case where users would never realize a capture was incomplete. Surface depth==1 failures at info so missing top-level iframes are visible in normal runs. Deeper nested failures stay at debug — chatty pages with many nested iframes (ad/tracker grids) can produce a lot of those. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The previous walker was a recursive Python function. CPython's default recursion limit is ~1000; very deep DOM trees would raise RecursionError which the outer broad-except silently swallowed — so deep pages lost closed-shadow exposure with no diagnostic. Switch to an explicit stack-based walker. Memory now scales with tree breadth rather than tree depth, and deeply linear chains (3000+ nodes) complete cleanly. Add pylint disable for too-many-nested-blocks (the shape of the iterative version trips the default cap of 5). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The 1.30.9 pin printed an "out of date by 10+ releases" warning on CI and appears to interact badly with the test harness on python 3.9/3.10 runs (the test process never gets past the warning banner). 1.31.14 is the current release line used across the other percy SDKs. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Calling the underscore-prefixed helper directly from a regression test is intentional — the function is the boundary the fix lives at. Disable the pylint warning class-wide so the lint gate stays green. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The earlier run (26355895088) had both Python 3.9 and 3.10 jobs stuck in_progress while Test (3.8) on the same run completed cleanly in 1m40s. Empty commit to kick a fresh CI run and supersede the hung jobs. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
…nd-shadow-dom # Conflicts: # package.json # percy/snapshot.py
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Summary
Brings percy-selenium-python to parity with the canonical Percy CORS iframe + closed shadow DOM feature set.
Implemented
data-percy-ignoreattribute opt-outignoreIframeSelectorsoptionis_unsupported_iframe_srcPercyContextLostrecovery mergespartial_captureexpose_closed_shadow_roots)Skipped
Reference
Mirrored from percy/percy-nightwatch#869 (PER-7292-add-cors-iframe-support); CDP from percy/percy-playwright#609.
Test plan
🤖 Generated with Claude Code via /percy-sdk-sync