[lawrencecchen]

Summary

Tip web-lint red since b695980 (STATUS 8746), from #33526 (webviews/test/agent-pane-streaming-no-flicker.test.ts):

• eslint(no-unused-vars): the outer type Box is never used. Each page.evaluate body declares its own Box (code there runs in the page and cannot see outer types). This PR removes the outer one.
• 7 TypeScript errors (TS2339/TS2352/TS2769) in the page listener: the file declares its own type Event (the acpmux event, line 74), which shadows the DOM Event in onAnimation. The parameter is now globalThis.Event.

No test logic changes.

Verification

• bunx vp lint test/agent-pane-streaming-no-flicker.test.ts in webviews/: 0 findings (base: the unused-var warning and 7 TS errors).
• scripts/web-lint.sh: passed. python3 scripts/cmux-next/prepush-gate.py: no new violations.

Observed / Not run

• Observed: the commands above, on this VM.
• Not run: the browser test itself (a webviews browser lane runs only in CI or a cloud VM, never on a fleet Mac).

Changelog

none

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Summary by cubic

Fixes type-checking and lint errors in the no-flicker agent pane test so the webviews lint passes on this base.

• Removes the unused outer Box type; each page.evaluate body declares its own.
• Types the onAnimation parameter as globalThis.Event, since the file's own Event type (the acpmux event) shadowed the DOM Event and caused 7 TypeScript errors.

No test logic changes.

^{Written for commit 8440e0b. Summary will update on new commits.}

[github-actions]

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Review 8440e0b: HQ feed card · gallery before/after runs · checks

App of this head (app.zip, kept 1 day)

gh workflow run reload-build.yml -R manaflow-ai/cmux --ref feat-cmux-next -f tag=pr33545 -f ref=fix/base-red-flicker-test-box -f platform=macos -f backend_mode=local

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4162023985101 (c8f5046a98)

[lawrencecchen]

Review (independent-subagent): SHIP at 8440e0b

Checked on a worktree of the head (base 0d430df):

• Outer type Box is unused. Its only other names are inside the two page.evaluate bodies (lines 236 and 325), and each declares its own Box.
• globalThis.Event is correct. type Event at line 74 (the acpmux event) is in the requireBrowserLane callback that encloses the page.evaluate body, so a bare Event resolved to it. webviews/tsconfig.json includes test with lib: ["DOM", ...], so globalThis.Event is the DOM Event. .target and .type resolve, the AnimationEvent / TransitionEvent casts are valid, and add/removeEventListener(kind, onAnimation, true) match an overload.
• No runtime change. Only type annotations change. Bun strips them, and Playwright serializes the page.evaluate function with toString(), so the page gets the same JS.
• bunx vp lint test/agent-pane-streaming-no-flicker.test.ts: head gives 0 findings, exit 0. Base gives 1 warning (no-unused-vars on Box, 222:8) and 7 TS errors (TS2339 / TS2352 / TS2769, lines 287 to 312), exit 1. bunx vp fmt --check on the file passes at head.

Not run: the browser lane test itself (it needs the Playwright browser lane). It is not necessary for a type-only change.