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qa-visual-regression

Visual regression testing: 7 skills (percy-visual-regression-testing, chromatic-visual-regression-testing, playwright-snapshots with the responsive breakpoint matrix, storybook-visual-regression-testing, chart-render-tests covering Chart.js / D3 / Vega chart regression, visual-baseline-conventions, visual-baseline-gate emitting binding gate artifacts) and 2 agents (visual-diff-classifier with a per-PR summary mode, visual-baseline-curator).

Install this plugin

/plugin install qa-visual-regression@testland-qa
View source

Part of role bundles: qa-role-automation-engineer, qa-role-sdet, qa-role-frontend

qa-visual-regression

Visual regression testing across Percy, Chromatic, Playwright snapshots, and Storybook visual tests, plus chart-render regression (Chart.js / D3 / Vega), adversarial diff classification with a per-PR summary mode, baseline curation, and a binding CI baseline gate.

Components

TypeNameDescription
Skillpercy-visual-regression-testingAuthor Percy snapshots via @percy/playwright/cypress/selenium/storybook; run with percy exec; review diffs in the Percy UI.
Skillchromatic-visual-regression-testingRun Chromatic on Storybook / Playwright / Cypress; configure baselines, TurboSnap, exit codes for CI gating.
Skillplaywright-snapshotsAuthor expect(page).toHaveScreenshot() assertions; configure mask/clip/threshold/maxDiffPixels; manage per-OS / per-browser snapshot dirs and --update-snapshots; responsive breakpoint-matrix reference.
Skillstorybook-visual-regression-testingWire visual regression into Storybook via @chromatic-com/storybook (hosted) or @storybook/test-runner postVisit + Playwright (self-hosted).
Skillchart-render-testsChart-render regression across the three library families: Chart.js canvas snapshots, D3 SVG structural snapshots + data-binding tests, Vega/Vega-Lite spec validation + compile test; per-library depth in references/.
Skillvisual-baseline-conventionsReference catalog: engine selection, story/page/breakpoint coverage, mask/threshold/wait decision matrix, severity tiering, anti-patterns.
Skillvisual-baseline-gateCI gate: aggregate diff classifications + acceptance log into a single go/no-go verdict; emit binding visual-gate.json + visual-gate.md artifacts; enforce author-cannot-self-approve.
Agentvisual-diff-classifierAdversarial reviewer of visual diffs: classify each as intentional / incidental / regression; per-PR summary-comment mode clusters 20+ diffs by component and intent.
Agentvisual-baseline-curatorBuilder: proposes a coverage-optimal initial baseline set, generates engine config files, runs a dry-run to verify the suite compiles.

Install

/plugin marketplace add testland/qa
/plugin install qa-visual-regression@testland-qa

Skills

chart-render-tests

Chart-render regression testing across the three chart-library families - Canvas (Chart.js: locator screenshot snapshot + `canvas.toDataURL()` diff with animations disabled), SVG (D3: `outerHTML` structural snapshot with generated-ID normalization + per-element data-binding tests), and declarative specs (Vega / Vega-Lite: JSON Schema validation + Vega-Lite → Vega compile test). Detects the family from package.json imports (chart.js / d3 / vega-lite), then applies the matching recipe; full per-library depth with citations in references/chartjs.md, references/d3.md, references/vega.md. Use when a dashboard or data product renders charts and their output needs regression coverage - before a chart-library major upgrade, after a theming change, or when runtime-generated Vega specs must be proven valid before render.

chromatic-visual-regression-testing

Authors and runs Chromatic visual tests on Storybook, Playwright, or Cypress projects via the `chromatic` CLI; configures baselines, TurboSnap, UI Review, and CI gating; reads exit codes for change-vs-error classification. Use when the project ships visual regression coverage to Chromatic Cloud.

percy-visual-regression-testing

Authors Percy visual snapshot tests via the @percy/cli + framework SDK (Playwright, Cypress, Selenium, Storybook), runs them with `percy exec -- {test command}`, configures viewports / masking / ignored regions, and reviews diffs in the Percy build UI. Use when the project ships visual regression coverage to BrowserStack Percy.

playwright-snapshots

Authors Playwright `expect(page).toHaveScreenshot()` assertions, configures masks / clips / threshold / maxDiffPixels per test, manages the per-OS / per-browser snapshot directory, and runs the update flow with `--update-snapshots`; references/ carry the responsive-breakpoint viewport matrix (one project per breakpoint, cross-breakpoint matrix report, plus Chromatic / Percy / Storybook test-runner viewport syntax). Use when the project ships self-hosted visual regression coverage in Playwright (no external snapshot service), or needs a unified multi-viewport breakpoint matrix.

storybook-visual-regression-testing

Sets up visual regression coverage for a Storybook project - either via the official @chromatic-com/storybook addon (hosted) or via @storybook/test-runner with a postVisit hook that calls Playwright's toHaveScreenshot (self-hosted). Covers test-runner install, lifecycle hooks (setup / preVisit / postVisit), and CI integration. Use when a repo already has a working `.storybook/` config and the team wants per-story visual coverage rather than page-level snapshots.

visual-baseline-conventions

Reference catalog for visual regression coverage decisions - which Storybook stories or pages get baselines, how to choose breakpoints, when to mask vs adjust threshold, when to add or remove a baseline, and a decision matrix for picking among Percy / Chromatic / Playwright / Storybook test-runner. Use when designing visual coverage for a new project or auditing an existing baseline set.

visual-baseline-gate

Consumes pre-classified visual-diff JSON and a reviewer-signed acceptance log to produce a single go/no-go CI verdict for visual regression. Blocks when intentional baseline changes lack a non-author reviewer sign-off or when regressions are present, and emits the binding gate artifacts - visual-gate.json + visual-gate.md - with fail-closed handling of a missing classifier run and author-cannot-self-approve enforcement, so the pipeline can exit non-zero on BLOCK. Use when the gate's input is pre-classified diff data and the enforcement concern is reviewer approval and a binding CI verdict.