Patch Group Benchmark

This manual benchmark mounts the production CurrentFileToolGroup and File components with completed edit results. A separate case mounts ToolDisplay with a patch result. It uses four real Core tool source files, with deterministic identifier renames, rather than repeated filler. It does not connect to a server.

From packages/app, set PATCH_BUILD_DIR and PATCH_RESULTS_DIR to external artifact directories, then run:

bun x vite build --config e2e/performance/patch-groups/vite.config.ts
bun x playwright test --config e2e/performance/patch-groups/playwright.config.ts --repeat-each=20

Run under the shared exclusive gate when collecting measurements on a shared machine. The Playwright-owned static server uses PATCH_PORT (default 4317), refuses to reuse an existing server, and shuts down after the run.

Each fresh browser context measures a cold collapsed mount, a warm remount, and opening edit.ts through its real accordion. Mount timing covers synchronous component construction through layout. Expansion timing starts at the click and ends at the production file renderer's onRendered callback. Assertions check the exact file count, collapsed state, and completed file rendering. Results include payload bytes, source bytes, file/tool counts, and supporting warm patchFileGroups timings with and without reading views. No timing thresholds are enforced. This is a browser component workload, not a full desktop memory test.

Freeze the build before changing production code. Use the same fixture, browser, viewport, sample count, and completion checks for both revisions.

PATCH_REVISION=<git-sha> loads the grouping module and tool renderer from that revision at build time without changing the worktree. This is useful when fixing the harness after freezing a baseline. All other production sources must match between revisions; this switch only covers those two measured modules.

For a separate diagnostic build, set PATCH_COUNTERS=1. Its build-only transform counts grouping, normalization, reconstruction, and line-diff calls with User Timing marks. Do not mix instrumented results with clean timings. Set OPENCODE_PERFORMANCE_TRACE_DIR for the existing Chrome trace collector, and PATCH_SCREENSHOTS=1 for collapsed/expanded screenshots after measurement.