#Testing
The whole suite runs under bun test — extractor code, SPA libraries, and Svelte components alike — with real-nix integration tests layered on top when nix is on PATH. See Build & infra for the CI jobs that run it.
#Running
bun test # full suite (nix-dependent tests skip if nix is absent)
bun test --coverage # text + lcov reportersbunfig.toml preloads two setup files for every test run and configures coverage (lcov output, test files skipped, test/** ignored):
| Preload | Purpose |
|---|---|
test/setup/happy-dom.ts |
Registers happy-dom as the global DOM and stubs matchMedia / ResizeObserver, which the viewer touches at init time |
test/setup/svelte-loader.ts |
A bun runtime plugin that compiles .svelte files with svelte/compiler (client output, injected CSS, runes) and .svelte.ts modules via compileModule — bun-plugin-svelte can't run under the test runtime because its virtual CSS imports need build-time resolution. It also swaps svelte's index-server.js package entries for their client siblings, since bun test resolves the "default" (server) export condition |
Component tests use the withMount helper in test/helpers.ts: mount into a fresh host element, flushSync(), assert, always unmount.
#Test inventory
26 *.test.ts files under test/, roughly four groups:
| Group | Files | Examples |
|---|---|---|
| Extractor & CLI unit tests | ~13 | test/options.test.ts, test/manifest-show.test.ts (captured nix flake show JSON), test/cache.test.ts, test/imports.test.ts, test/highlight.test.ts (vendored tree-sitter WASM, no nix needed), test/cli-help.test.ts (CLI as a subprocess), test/page-html.test.ts (the </script> escaping invariant) |
| SPA library tests | ~8 | test/state.test.ts, test/state-loading.test.ts (loads resolve through embedded <script> tags injected into happy-dom — no network), test/hash.test.ts, test/indexes.test.ts, test/color.test.ts, test/url.test.ts |
| Component tests | ~4 | test/app.test.ts (fixture data injected into the app singleton, components mounted under happy-dom), test/option-row.test.ts, test/output-branch.test.ts, test/input-provenance.test.ts |
| Real-nix integration | 2 | test/mini-flake.test.ts (full buildManifest + extractOptions pipeline), test/export.test.ts (end-to-end single-file export, then re-parses the embedded data tags out of the HTML) |
#Fixture strategy
test/fixtures/mini-flake/flake.nix— a real flake evaluated by real nix, but builtins-only (no nixpkgs), so evaluation is cheap and no store downloads happen. It hand-rolls just enough of the module-system option shape (_type = "option",declarations,definitionsWithLocations) for the extractor's structural walk, and includes a nestedpath:input to exercise the Inputs panel.test/fixtures/broken-flake/flake.nix— a flake whose one configuration throws on evaluation: the attr name is enumerable but forcing the value fails, exercising the per-config error/degradation path without poisoning the healthy fixture.test/fixtures/data.ts— hand-writtenManifest/ConfigData/OptionEntrybuilders shared by unit and component tests, with fake store paths for self, inputs, and a patched-input copy.
#FLAKE_EXPLORER_REQUIRE_NIX
The integration suites use describe.skipIf(!hasNix), which is right for local machines without nix but dangerous in CI — a skipped suite would only show up as a coverage drop. Setting FLAKE_EXPLORER_REQUIRE_NIX=1 makes test/mini-flake.test.ts and test/export.test.ts throw at load time if nix is not on PATH. CI's test job sets it (with nix installed) so a silent skip is impossible — see .github/workflows/ci.yml.
#Coverage and the Nix check
Coverage is enforced as a ratchet by octocov: .octocov.yml reads coverage/lcov.info with acceptable: current >= prev, comparing PRs against the report stored from the default branch — coverage can rise but never regress. Current coverage sits in the mid-90s of lines.
Separately, nix flake check runs checks.test (flake.nix): an offline bun test inside the build sandbox against the vendored node_modules from package.nix. The sandbox has no nix binary, so the real-nix suites skip there by design; the CI test job is where they must run.