Formats and prints a single QUnit testEnd event as a TAP ok/not ok line with an optional YAML failure block. A pure formatter: testNumber is the TAP sequence number (the caller owns counting) and failures are pre-resolved by failedAssertions.

import * as TAP from './index.ts';

import type { TestDetails } from '../reporters/types.ts';
import type { FailureInfo } from '../reporters/failure.ts';

// Defined, not invoked: writes the TAP line (plus YAML failure blocks) to the run's output.
function example(details: TestDetails, failures: FailureInfo[]) {
  TAP.displayTestResult(3, details, failures);
  // "not ok 3 Math | adds # (2 ms)" then one "  ---" YAML block per failure
}