When a feature depends on multiple probes/loads, ensure that failures in secondary/best-effort steps don’t corrupt primary state or cause cascading failures.
Apply this in two ways: 1) Runtime/state handling: keep authoritative flags separate from enrichment fields.
pip list, optional extras) as best-effort: on failure, return safe defaults for only the enrichment fields, not the primary flag.Example pattern:
export async function getStatus(url) {
const installed = Boolean(pathFromCliProbe);
// Best-effort enrichment; should NOT affect `installed`.
let extras = { version: null, extras: { code: false, ml: false } };
try {
if (installed) extras = await getInstalledHeadroomExtras();
} catch {
// swallow or log; keep primary state stable
}
return { installed, ...extras };
}
2) Test structure: fail fast in setup.
before()/setup hook.undefined values that produce many misleading downstream errors.Example pattern:
import { before, it } from "node:test";
import assert from "node:assert/strict";
let entry;
before(async () => {
entry = (await import("../../path/to/module.js")).default;
});
it("has expected id", () => {
assert.equal(entry.id, "kimchi");
});
This prevents both incorrect UI/business logic (wrong state derived from a failing secondary probe) and noisy, cascading test failures that obscure the real cause.