File size: 1,245 Bytes
3e05655 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 | import { expect, test } from "bun:test"
import { summarizeFirstNavigation } from "../timeline/first-navigation-metrics"
test("reports blank frames before first destination and stable paint", () => {
expect(
summarizeFirstNavigation([
{ observedAtMs: 16, source: true, destination: false, content: true },
{ observedAtMs: 32, source: false, destination: false, content: false },
{ observedAtMs: 48, source: false, destination: true, content: true },
{ observedAtMs: 64, source: false, destination: true, content: true },
{ observedAtMs: 80, source: false, destination: true, content: true },
]),
).toEqual({
samples: 5,
firstDestinationObservedMs: 48,
stableDestinationObservedMs: 80,
sourceSamples: 1,
blankSamples: 1,
unknownSamples: 0,
destinationSamples: 3,
})
})
test("does not report stability for interrupted destination frames", () => {
expect(
summarizeFirstNavigation([
{ observedAtMs: 16, source: false, destination: true, content: true },
{ observedAtMs: 32, source: false, destination: false, content: true },
{ observedAtMs: 48, source: false, destination: true, content: true },
]).stableDestinationObservedMs,
).toBeNull()
})
|