Roll Playwright

Roll playwright-go to a new Playwright version

Roll the client from the currently-pinned version to a target version (e.g. 1.61.0). Work autonomously; only stop for the decision points called out in When to ask the user. The job isn't done when the PR opens — it's done when CI is green (Step 11), so expect to iterate on cross-browser/cross-OS failures that don't reproduce locally.

What a roll actually is

playwright-go vendors microsoft/playwright as a git submodule (playwright/) pinned to a tag. The public Go API (generated-*.go) is generated from the submodule's docs/src/api/*.md by playwright/utils/doclint/generateGoApi.js. Those .md files gate each API by language with a * langs: line; the Go client only sees an API if go is in that line. patches/main.patch is a diff applied onto the upstream submodule that (a) adds the Go generator and (b) adds go to the * langs: of every API the Go client exposes.

So a roll = bump the version, re-apply the patch onto the new submodule, add go to the langs of any newly-added APIs we want, regenerate, build, test.

Inputs

• Target version, e.g. 1.61.0 (the v is optional). If not given, default to the latest stable from gh release list --repo microsoft/playwright --limit 5 and confirm with the user.
• Current version is read from run.go (const playwrightCliVersion).

Prerequisites (check, install if missing)

gh (authenticated), node, go, gofumpt (go install mvdan.cc/gofumpt@latest), jq. The submodule must be initialized: git submodule update --init.

Step 1 — Discover what changed

Run the helper, which prints the upstream docs diff, every new * since: vNEW API with its langs: line, and the sibling roll PRs:

bash .claude/skills/roll-playwright/find-changes.sh <NEW_VERSION>

Required: locate the actual roll PR in all three sibling clients (python, java, dotnet) before porting — you need all three as references, not just one. They are the source of truth for which new APIs are real client surface, their exact method/param names, types, defaults, optionality, AND which upstream PRs were skipped. The helper prints candidates; for each repo open the right PR and confirm it's the one that ports the API surface (not a no-op bump):

gh pr view <num> --repo microsoft/playwright-python   # body enumerates ported APIs
gh pr view <num> --repo microsoft/playwright-java      # body links each upstream PR ported + what was skipped
gh pr view <num> --repo microsoft/playwright-dotnet

If a repo's helper line is missing or looks like a no-op, dig with the queries in references/finding-changes.md until you have a real roll PR for each of the three. Use python as the primary shape reference (closest to Go), java for the per-upstream-PR breakdown, dotnet for option/enum shapes.

Critical: the heavy API port usually lands in the -beta / -alpha roll PR, not the final X.Y.0 PR (which is often a one-line version bump — e.g. python v1.60.0 final roll was +1/−1, the beta roll +2194/−226). Read the beta/feature roll for the real changes.

Build a checklist of new/changed APIs to expose in Go, AND a checklist of the new tests each sibling added (you'll port these in Step 6b). The Go client deliberately omits some upstream APIs (e.g. some Electron/Android/JS-internal surface) — match python's choices unless there's reason not to.

Watch for return-type naming: new return-object types carry a * alias: in the docs (e.g. * alias: VirtualCredential, * alias: WebStorageItem). The Go generator does NOT honor it by default and falls back to a generic method-derived name (Create, Get, Item). If you see a generic/duplicate generated struct name, add a guarded special-case in generateGoApi.js generateNameDefault (scoped by parent.name) mapping it to the documented alias — see references/patch-editing.md. Watch for pure getters: a new no-arg getter (e.g. Page.LocalStorage(), BrowserContext.Credentials()) generates with a trailing error return unless its method name is in methodNoErrArray in generateGoApi.js. Add it there so it matches sibling getters like Clock()/Mouse().

Step 2 — Bump the version

1. Edit run.go: set const playwrightCliVersion = "<NEW_VERSION>".
2. Download the new driver (also advances browser versions for the README step):

   go run scripts/install-browsers/main.go
   

Step 3 — Apply the patch onto the new submodule

bash scripts/apply-patch.sh

This checks out the new tag in playwright/, creates branch playwright-build, and runs git apply --3way patches/*. Two outcomes:

• Clean apply → continue to Step 4.
• Merge conflicts (.rej files, or <<<<<<< markers in playwright/docs/src/api/*.md) → upstream edited a line the patch also touched. Resolve them: keep the upstream change AND re-add go to the * langs: line. Then cd playwright && git add -A && git commit -am "apply patch" && cd ...

Step 4 — Add go to new APIs (the real work)

For each new API from your Step 1 checklist that you want in Go, edit the matching block in playwright/docs/src/api/class-*.md (and params.md) so its * langs: line includes go. The patch in Step 5 is regenerated from these edits.

cd playwright
git reset --soft HEAD~1   # un-commit the applied patch so edits fold into one diff (keeps working tree)
# ...edit docs/src/api/*.md: add `go` to the `* langs:` lines of the new APIs...
git add -A && git commit -m "apply patch"
cd ..

Rules for editing langs (see references/patch-editing.md for details and examples):

• * langs: js, python, csharp → * langs: js, python, csharp, go (append, comma+space).
• A Go-only addition uses * langs: go.
• Keep edits surgical — only touch lines for APIs you're intentionally exposing.
• Mirror the python client's method/param naming and optionality; the Go generator turns these docs into generated-*.go.

Step 5 — Regenerate the patch and the Go API

bash scripts/update-patch.sh      # regenerates patches/main.patch from the playwright-build branch
go generate ./...                 # runs generate-api.sh: re-applies patch, runs the JS generator, gofumpt

go generate rewrites generated-enums.go, generated-interfaces.go, generated-structs.go. Review the diff — it should reflect exactly the APIs you added.

Gotcha: generate-api.sh ends with git submodule update, which resets playwright/ back to the parent repo's currently pinned (old) commit. After generation you MUST bump the gitlink yourself: (cd playwright && git checkout v<NEW_VERSION>), then confirm with git submodule status playwright. Otherwise the committed submodule pointer still references the old version. Do this as part of Step 9.

Step 6 — Hand-written wiring

The generator produces interfaces/structs, but most new APIs need a hand-written implementation in the corresponding *.go file (e.g. a new Page method goes in page.go, often with a channel send). Use the sibling clients' impl (python _impl/*.py, java/dotnet Core/impl) as the behavior reference. Look at a previous roll commit for the pattern:

git show $(git log --oneline --grep="[Rr]oll to" -1 --format=%H) --stat   # files a past roll touched

New thin wrapper classes (not channel owners) follow clock.go: a struct holding the parent *pageImpl/*browserContextImpl, constructed in the parent's newPage/newBrowserContext, exposed via a getter, methods call parent.channel.Send(...). Wire the getter field into the parent struct too.

Watch for protocol behavior changes (not just new APIs) — these don't show as build errors but break at runtime. Check the sibling roll PR bodies and the upstream validator.ts diff (gh api .../compare/vOLD...vNEW) for renamed channel methods, split methods, or changed result shapes. Example from v1.61: assertion expect stopped returning {matches} and now throws a protocol error carrying errorDetails — every assertion path had to be updated. Grep for duplicated logic (e.g. there were TWO expect call-sites: locatorImpl.expect and pageAssertionsImpl.expectOnFrame) so you fix all of them.

Step 6b — Port EVERY sibling test (required)

Mandatory and exhaustive: every test python, java, AND dotnet added in their roll PR must have a Go counterpart in tests/. Do not cherry-pick — enumerate all of them and port each, following Go conventions (BeforeEach(t), require, server.EMPTY_PAGE, per-browser branches via isChromium/isFirefox/isWebKit). This is both for coverage parity and because a sibling test frequently exposes a feature that is broken or missing in Go — porting it is how you find that.

Real example (v1.61): java's getByTestIdWithCommaSeparatedTestIdAttributesShouldMatchAny had no Go equivalent. Porting it revealed that comma-separated SetTestIdAttribute produced an invalid selector in Go (the encodeTestIdAttributeName quoting was missing). The test caught a real bug — the impl had to be fixed, not just the test added.

Build a complete checklist. List every test function each sibling added, then tick off the Go equivalent:

# 1. List the test FILES each sibling roll added/changed:
for repo in microsoft/playwright-python microsoft/playwright-java microsoft/playwright-dotnet; do
  echo "## $repo"; gh pr view <num> --repo $repo --json files --jq '.files[].path' | grep -iE 'test|spec'
done

# 2. Extract the test FUNCTION NAMES added (so nothing is missed):
gh pr diff <pyNum>  --repo microsoft/playwright-python  | grep -E '^\+\s*(async )?def test_'
gh pr diff <javaNum> --repo microsoft/playwright-java   | grep -E '^\+\s*(public )?void '
gh pr diff <netNum>  --repo microsoft/playwright-dotnet | grep -iE '^\+\s*public async Task|\[(Playwright)?Test\]'

# 3. For each, read the body and port the cases:
gh pr diff <num> --repo <repo>

For each new API, dedupe across the three (they overlap heavily) and port the union of their cases — e.g. python tests session-storage clear separately, java tests local/session independence; port both. If a sibling test can't be ported (feature intentionally not in Go, or needs an unavailable fixture like an HTTPS server), log it explicitly with the reason rather than silently dropping it.

These tests are also your verification that the impl works — run them across all three browsers in Step 7 (a test green on chromium may fail on firefox/webkit due to engine-specific error strings or behavior).

Step 7 — Build, lint, test

gofumpt -l -w .
go build ./...
go vet ./...
golangci-lint run ./...             # CI's Lint job; fails on errcheck/staticcheck/gofumpt
# Run the NEW tests on every browser — CI is a 3 OS x 3 browser matrix and
# engine-specific behavior (error strings, etc.) differs. A pass on chromium
# alone is NOT enough.
for b in chromium firefox webkit; do BROWSER=$b HEADLESS=1 go test -race ./tests/ -run '<NewTests>'; done
go test -race ./...                 # full suite at least once

Lint commonly fails on test helpers: unchecked defer x.Close()/Stop() (errcheck → add //nolint:errcheck), deprecated WaitForTimeout (staticcheck → use time.Sleep), and gofumpt alignment. Run golangci-lint run locally; the CI Lint job is fast but blocking.

Cross-browser is not optional: a v1.61 client-cert assertion passed on chromium but failed on firefox (SSL_ERROR_UNKNOWN), webkit-linux/macos (Certificate is required), and webkit-windows (Failure when receiving data) — each emits a different error string. Match any known variant rather than one browser's wording.

The verify_type_generation CI job runs go generate and fails if it produces a diff — so committed generated-*.go must exactly match a fresh generation. Run go generate ./... once more and confirm git diff --ignore-submodules is clean for the generated files.

Step 8 — Update README versions

Already handled inside scripts/generate-api.sh (it runs update-readme-versions/main.go), but if you ran steps manually, run go run scripts/update-readme-versions/main.go to refresh the browser-version badges.

Step 9 — Verify parity against the sibling clients

Before committing, run the parity verifier. It cross-checks this roll's diff against what python/java/dotnet did, so you catch anything missed: a new * since: vNEW API the siblings expose but you didn't add go to, an API you exposed that no sibling did, or a sibling test you haven't ported.

bash .claude/skills/roll-playwright/verify-parity.sh <NEW_VERSION>

It reports three buckets:

1. New upstream APIs not in Go — each * since: vNEW block whose * langs: still lacks go. For each, decide: intentionally omitted (matches a sibling skipping it) or a miss to fix in patches/main.patch.
2. Sibling tests added this roll — the test files AND the individual test function names from all three clients, so you can tick off that each has a Go counterpart in tests/ (Step 6b).
3. Go API symbols added vs sibling API surface — a rough name-level diff to spot a method you exposed that no sibling did (often a naming mistake) or vice-versa.

Treat each flagged item as needing an explicit decision: fix it, or note why Go intentionally differs. The goal is that any remaining difference from python/java/dotnet is deliberate and explainable.

Step 10 — Commit & PR

Branch name should start with roll/ (CI triggers on roll/*). Match the existing commit style:

# Bump the submodule gitlink to the new tag (generate-api.sh reset it — see Step 5 gotcha):
(cd playwright && git checkout v<NEW_VERSION>)
git submodule status playwright          # confirm it shows v<NEW_VERSION>
git diff --submodule=log -- playwright   # confirm the pointer moves OLD -> NEW

git checkout -b roll/v<NEW_VERSION>
git add -A && git commit -m "chore: roll to Playwright v<NEW_VERSION>"
git push -u origin roll/v<NEW_VERSION>
gh pr create --repo mxschmitt/playwright-go --base main \
  --title "chore: roll to Playwright v<NEW_VERSION>" --body "<summary of new APIs + behavior changes>"

Create the PR when the local checks (Step 7/9) pass — don't wait to be asked. Summarize the new APIs and any behavior changes in the body, and always end the body with this footer so it's obvious at a glance the PR was skill-generated rather than hand-rolled (write the body to a temp file and pass --body-file if it's easier than escaping a multi-paragraph --body string):

---
🤖 Rolled with the [`roll-playwright`](.claude/skills/roll-playwright/SKILL.md) skill.
Sibling references used: python <PR_URL>, java <PR_URL>, dotnet <PR_URL>
verify-parity.sh (Step 9): <clean | N items flagged and how each was resolved>

Fill in the three sibling PR URLs found in Step 1 — if any was unavailable or skipped, say so explicitly on that line rather than omitting it (this is also a forcing function: don't skip the Step 1 requirement to check all three). Then drive it to green (Step 11).

Step 11 — Drive CI to green (loop until all checks pass)

The roll is not done when the PR opens — it's done when CI is green. A roll PR runs a large matrix (3 OS × 3 browsers × 2 Go versions) plus Lint, verify (type generation), and test-examples. Local chromium-green is not sufficient — most roll failures surface only on firefox/webkit or on Windows. Loop autonomously until every check passes:

1. Wait for the run to finish (don't poll in a tight loop — block on it):

   # Find the run for the branch's head commit, then watch it to completion:
   RUN=$(gh run list --repo mxschmitt/playwright-go --branch roll/v<NEW_VERSION> \
     --limit 1 --json databaseId --jq '.[0].databaseId')
   gh run watch "$RUN" --repo mxschmitt/playwright-go --exit-status
   # (exits non-zero if the run failed; `gh pr checks <num> --watch` is an alternative.)
   

2. List results and read every failure's log (the failed step, not the whole log):

   gh pr checks <num> --repo mxschmitt/playwright-go
   gh run view --repo mxschmitt/playwright-go --job <jobId> --log-failed \
     | grep -iE 'FAIL|Error:|\.go:[0-9]+|panic'
   

3. Triage each failure the same way as Step 6 / "behavior changes": is it my code, an engine/OS-specific string (match any known variant), a lint issue, or an intended upstream change? Note the OS+browser — a failure on only webkit-windows is still a failure.
4. Fix, re-verify locally on the affected browser(s), and re-push (amend the relevant commit to keep history clean; --force-with-lease). Re-run from step 1.
5. Repeat until gh pr checks shows 0 fail and no relevant pending.

• Flakiness.io is a reporter, not a merge gate — it shows "fail" only because a test job it reports on failed; it goes green when the tests do. Don't chase it directly.
• A genuinely flaky (not roll-caused) test that fails once may pass on re-run; confirm it's unrelated to your changes before re-running rather than fixing. The repo uses flakiness-go (no auto-retry).
• Each push triggers a fresh run; gh run list --branch returns the newest first. Watch the run for the current head commit, not a stale one.

Rebasing when main moves

A roll commit always touches run.go (version) and README.md (browser-version badges), so if main advances during review you'll get conflicts there — resolve by keeping main's structure and your roll's values:

• run.go: if main turned the version into a const (...) block (e.g. added nodeVersion/registry constants), keep that block and just set playwrightCliVersion to the new version.
• README.md: keep main's badge text/links, keep your bumped version numbers inside the <!-- GEN:* --> markers.

git fetch origin main && git rebase origin/main
# resolve run.go / README.md as above, then:
git add run.go README.md && git rebase --continue
# re-verify generation is idempotent + submodule still pinned, then force-push:
go generate ./... && (cd playwright && git checkout v<NEW_VERSION>)
git diff --ignore-submodules generated-*.go   # must be empty
git push --force-with-lease origin roll/v<NEW_VERSION>

Existing tests may need updating for behavior changes

A roll can change the behavior of an existing API, breaking a test that asserts the old behavior — this is not a port bug. When a pre-existing test fails:

1. Confirm you didn't break it (does it fail because of a signature/impl change you made?).
2. If not, check whether upstream changed that behavior: read the relevant sibling roll-PR test diffs and the upstream source diff (gh api .../compare/vOLD...vNEW --jq '.files[].filename' then inspect the changed server file). Example from v1.61: socksClientCertificatesInterceptor.ts was rewritten so a client cert is only presented to its matching origin — so the client-cert test's origin-mismatch navigation went from "503, no cert" to "TLS handshake aborted (net::ERR_BAD_SSL_CLIENT_AUTH_CERT)". Update the assertion to the new behavior.
3. New error/abort behaviors can introduce async navigation races (an aborted nav triggers a chrome-error:// navigation that interrupts the next Goto with "is interrupted by another navigation"). Retry the follow-up navigation in a small loop (see gotoSettled in browser_context_client_certificates_test.go) rather than asserting once.

When to ask the user

• Target version is ambiguous or unreleased upstream.
• A new upstream API is non-trivial (new class, breaking signature change) and you're unsure whether Go should expose it or how to name it.
• A pre-existing test fails and after investigation you're genuinely unsure whether it's an intended upstream behavior change (update the test) or a port bug (fix the code). If the evidence is conclusive (e.g. an upstream source rewrite + the Go client doesn't implement that logic), proceed and flag it; otherwise ask.

Otherwise work the whole flow autonomously, including creating the PR (Step 10) and iterating on pushes until CI is green (Step 11) — those don't need approval. Do NOT merge the PR; leave that to a maintainer. (If the user explicitly said not to open a PR, stop after Step 9 and report instead.)

Files & references

• find-changes.sh — discovery helper (read-only): upstream docs diff, new * since: APIs, sibling roll PRs.
• verify-parity.sh — parity verifier (read-only, Step 9): new APIs missing go, sibling test functions to port, Go-symbol diff.
• references/finding-changes.md — exact gh queries + roll-PR conventions for python/java/dotnet + upstream compare.
• references/patch-editing.md — anatomy of patches/main.patch, * langs: gating, editing the generator (methodNoErrArray, return-type aliases), conflict resolution.

Gotchas

• CONTRIBUTING.md references packages/protocol/src/protocol.yml — stale. The protocol is now packages/protocol/spec/*.yml, and it rarely changes between minors.
• GitHub search tokenizes versions oddly: searching a bare minor like 1.61 matches nothing; use the full 1.61.0, or list all roll PRs and filter locally (what the helper does). When filtering with jq, use contains("1.61") not test("1.61") — test is a regex where . matches any char (false positives like 1.3.0-next.106133).
• Single-quote any gh api URL containing ? (zsh globs on ?).
• apply-patch.sh deletes and recreates the playwright-build branch each run — safe to re-run. (It now also always checks out the pinned tag first — a fix for the first-roll-on-fresh-submodule case where it used to patch the old version.)
• generate-api.sh ends with git submodule update, resetting playwright/ to the OLD pinned commit. Re-checkout the new tag before committing (Step 10).
• The .0 sibling roll PR is often just a version bump; the API port is in the preceding -beta/-alpha PR.
• New API blocks with no * langs: line at all default to all languages (incl. go) and are generated without any patch edit — the patch edits are only for blocks that explicitly exclude go.
• Run go test -race before finishing: a new test that exercises a previously-untested API (e.g. an event callback) can surface a latent data race in existing impl code, not just your test. Fix the impl (guard shared fields with a mutex), don't just adjust the test.