INTER-2322: e2e test CI matrix for examples (React 18 & 19)

[JuroUhlar]

• Adds a Playwright e2e matrix that builds and serves each example, then asserts a visitor ID renders in the browser (React 18 + 19; Preact once via preact/compat).
• e2e/examples.ts is the single source of truth (example → build+serve command + port); CI selects one via EXAMPLE.
• Optional *_FPJS_REGION support in every example (default behavior unchanged).
• Fixes found while wiring this: missing CRA react-app-env.d.ts; remove broken Preact preact.config.js (redundant with CLI env injection).

Closes INTER-2322.

Discussion point: build+serve instead of dev

E2e boots production builds (build then start/preview/serve) so bundling failures (and each example’s own typecheck, where it has one) fail before Playwright. Preact folds tsc into its build script because preact-cli itself does not typecheck.

Required CI config

Settings → Secrets and variables → Actions:

• FPJS_PUBLIC_API_KEY — public API key (secret or variable)
• FPJS_REGION — optional us | eu | ap (must match the key when set)

The workflow fails fast if the API key is missing, or if FPJS_REGION is set to an invalid value.

Matrix

Example	React 18	React 19
create-react-app, vite, webpack-based, next, next-appDir	✅	✅
preact	once (preact/compat)	—

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟢	Statements	82.84%	111/134
🟡	Branches	67.57%	50/74
🟢	Functions	80.95%	34/42
🟢	Lines	82.31%	107/130

Test suite run success

22 tests passing in 15 suites.

Report generated by 🧪jest coverage report action from 8e2846b

Show full coverage report

St	File	% Stmts	% Branch	% Funcs	% Lines	Uncovered Line #s
🟢	All files	82.83	67.56	80.95	82.3
🟢	src	88.52	74.07	83.33	88.33
🟢	detect-env.ts	90	83.33	100	90	15,87
🟢	env.ts	100	100	100	100
🟢	env.types.ts	83.33	0	50	83.33	14
🟡	...nt-context.ts	75	100	0	75	8
🟡	get-env.ts	60	0	100	60	8-9
🟢	ssr.ts	100	100	100	100
🟢	...sitor-data.ts	95.65	100	80	95.65	102
🟢	src/components	91.66	58.33	91.66	91.17
🟢	...-provider.tsx	90.32	54.54	90.9	89.65	47,52,85
🟢	...vironment.tsx	100	100	100	100
🟡	src/utils	64.86	69.56	66.66	63.88
🟡	...is-defined.ts	50	75	100	50	3
🟡	to-error.ts	66.66	50	100	66.66	6
🟢	...mise-store.ts	91.3	92.3	100	90.9	20,26
🔴	wait-until.ts	0	0	0	0	8-19

[Copilot]

Pull request overview

Adds a Playwright end-to-end test suite and GitHub Actions matrix to build+serve each example app (React 18 + React 19; plus a one-off Preact run), then assert a visitor ID renders in the browser. This also standardizes example outputs for e2e by adding a shared data-testid="visitor-id" target and optional *_FPJS_REGION env support across examples.

Changes:

• Introduces e2e/ Playwright config + tests, plus a CI workflow that runs a per-example matrix across React 18/19.
• Updates examples to render a consistent visitor-id test target and to optionally pass region into FingerprintProvider.
• Adjusts example build/serve scripts and adds required tooling deps (@playwright/test, sirv-cli) and ignores Playwright artifacts.

Reviewed changes

Copilot reviewed 37 out of 42 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tsconfig.eslint.json	Includes e2e/**/*.ts in ESLint’s TS project scope.
pnpm-lock.yaml	Locks new dev deps (Playwright + sirv-cli) and related transitive changes.
package.json	Adds test:e2e script and Playwright dev dependency.
examples/webpack-based/webpack.config.js	Makes dotenv loading tolerant of missing .env.local and allows CI env fallback.
examples/webpack-based/src/index.js	Adds optional region env parsing and passes region to provider.
examples/webpack-based/src/App.js	Renders visitor ID in a consistent data-testid="visitor-id" span.
examples/webpack-based/package.json	Adds production build mode and serve command (sirv).
examples/webpack-based/.env.example	Documents optional REACT_APP_FPJS_REGION.
examples/vite/src/vite-env.d.ts	Declares optional VITE_FPJS_REGION.
examples/vite/src/main.tsx	Parses optional region env and passes region to provider.
examples/vite/src/App.tsx	Renders visitor ID in a data-testid="visitor-id" span and simplifies hook usage.
examples/vite/package.json	Pins preview port/strictPort and adds typecheck script.
examples/vite/.env.example	Documents optional VITE_FPJS_REGION.
examples/preact/src/index.tsx	Parses optional region env and passes region to provider.
examples/preact/src/env.d.ts	Adds a minimal process.env.PREACT_APP_* declaration for TS without Node types.
examples/preact/src/components/app.tsx	Adds data-testid="visitor-id" to the visitor-id element.
examples/preact/preact.config.js	Removes custom dotenv/DefinePlugin injection.
examples/preact/package.json	Adds typecheck and runs it as part of build; removes dotenv dep.
examples/preact/.env.example	Documents optional PREACT_APP_FPJS_REGION.
examples/next/pages/index.tsx	Adds data-testid="visitor-id" around the visitor ID.
examples/next/pages/_app.tsx	Parses optional NEXT_PUBLIC_FPJS_REGION and passes region to provider.
examples/next/package.json	Fixes start port and adds typecheck.
examples/next/.env.example	Documents optional NEXT_PUBLIC_FPJS_REGION.
examples/next-appDir/package.json	Fixes start port and adds typecheck.
examples/next-appDir/app/layout.tsx	Parses optional NEXT_PUBLIC_FPJS_REGION and passes region to provider.
examples/next-appDir/app/HomePage.tsx	Adds data-testid="visitor-id" around the visitor ID.
examples/next-appDir/.env.example	Documents optional NEXT_PUBLIC_FPJS_REGION.
examples/create-react-app/src/shared/utils/env.ts	Adds optional REACT_APP_FPJS_REGION parsing/export.
examples/create-react-app/src/shared/components/VisitorDataPresenter.tsx	Wraps visitor ID in data-testid="visitor-id" for e2e targeting and tightens rendering checks.
examples/create-react-app/src/session_storage_cache/SessionStorageCache.tsx	Passes region into provider.
examples/create-react-app/src/react-app-env.d.ts	Adds CRA type refs and CSS module declaration to fix TS compatibility.
examples/create-react-app/src/no_cache/WithoutCache.tsx	Passes region into provider.
examples/create-react-app/src/local_storage_cache/LocalStorageCache.tsx	Passes region into provider.
examples/create-react-app/src/in_memory_cache/InMemoryCache.tsx	Passes region into provider.
examples/create-react-app/package.json	Adds sirv-based serve and a typecheck script.
examples/create-react-app/.env.example	Documents optional REACT_APP_FPJS_REGION.
e2e/tests/example.spec.ts	Adds a framework-agnostic Playwright test asserting the visitor ID renders.
e2e/README.md	Documents how the e2e system works and how to run it locally.
e2e/playwright.config.ts	Adds Playwright config that builds+serves the selected example via EXAMPLE.
e2e/examples.ts	Defines the example→command/port mapping and resolveExample.
.gitignore	Ignores Playwright reports, test results, and e2e cache.
.github/workflows/e2e.yml	Adds CI job matrix to run e2e per-example across React 18/19 (+ Preact).

Files not reviewed (1)

• pnpm-lock.yaml: Generated file

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[github-actions]

🚀 Following releases will be created using changesets from this PR:

@fingerprint/react@3.1.0

Minor Changes

• Add support for React 19 and Next.js 16. The react peer range now accepts >=18 <20. (b539205)

Patch Changes

• Bump @fingerprint/agent dependency to ^4.1.2 (87b776f)