test: cover every line and function of the SPA

[bgard68]

Raises SPA coverage from 38.14% of lines to 100% of lines and 100% of functions, and the suite from 44 tests to 266. All green.

Heads up: merging this to frontend triggers .github/workflows/deploy.yml, which builds, runs the test gate, and deploys to Azure Static Web Apps.

Tooling

• @vitest/coverage-v8, configured in vite.config.js over src/**/*.{js,jsx}, excluding main.jsx (which only mounts the app) and the test files.
• npm run test:coverage.

Tests

• apiClient.js had no tests at all and is the file most worth having them: the 401 refresh-and-retry, the shared in-flight refresh that stops two simultaneous 401s from replaying the same rotating token and revoking every session, the cold-start backoff for Azure's Free tier, error mapping, and each Auth/Category/Todo call's verb, path and body.
• App.jsx — the silent sign-in on load and each way it can fail, the waking-the-server note, sign-in, register, Google, sign-out, sign-out everywhere, and the mid-session revocation that drops back to the form.
• KanbanBoard, Lane, TaskCard, CategoryManager — lane bucketing, the category filter and its fallback when the selected category is deleted, drag and drop, the tap-to-move control touch devices need, editing, and deletion.
• useTodos, useCategories — optimistic update, reconcile, and the reload that reverts a failed one.
• GoogleButton, ColorPicker, DateField, AuthForm, TodoForm, ThemeToggle, colors — the remaining branches, including theming and the offline paths.

No application source changed — this is test files plus vite.config.js, package.json, .gitignore and README.md.

Two jsdom conventions the suite depends on

Both are written up in the README so they are not rediscovered the hard way:

• Pointer coordinates. jsdom has no PointerEvent, and fireEvent.pointerDown silently drops clientX/clientY on its fallback event — which feeds NaN into the colour wheel's maths and makes a broken assertion look like a passing one. ColorPicker.test.jsx dispatches a MouseEvent named pointerdown instead, which carries the coordinates and still reaches React's handler.
• Layout. Nothing has a size in jsdom, so components that measure themselves (the colour wheel, the Google button) get an explicit getBoundingClientRect in the tests that care.

What is not covered

Thirteen branches, all guards that cannot be taken as the code stands — a ref checked for null on the element the same render creates, WHEEL_RADIUS ? … : 0 on a non-zero constant, a formatDate null check behind a caller that already tested the value. They are worth keeping as guards and not worth contorting a test to reach, so the branch figure reads 96.51% rather than 100%.

Verification

npm test — 19 files, 266 tests, 0 failures. npm audit — 0 vulnerabilities.

🤖 Generated with Claude Code

https://claude.ai/code/session_019h7znwAftvs36vD4YwKMRf

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Generated by Claude Code

[github-actions]

Azure Static Web Apps: Your stage site is ready! Visit it here: https://salmon-field-054249810-139.centralus.7.azurestaticapps.net

[github-actions]

Azure Static Web Apps: Your stage site is ready! Visit it here: https://salmon-field-054249810-139.centralus.7.azurestaticapps.net