Filtering and controlling test runs

The test runner has flags for the everyday loops: run one test by name, stop at the first failure, rerun on save, and spread test files across CPU cores. This example demonstrates each on a small test file.

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import { assertEquals } from "jsr:@ende/assert";

Ende.test("addition", () => {
  assertEquals(1 + 1, 2);
});

Ende.test("subtraction", () => {
  assertEquals(2 - 1, 1);
});

Ende.test("async work completes in time", async () => {

There is no built-in per-test timeout, so race the work against a deadline. Clearing the timer keeps the sanitizers happy.

  await withTimeout(Promise.resolve("done"), 1000);
});

function withTimeout<T>(work: Promise<T>, ms: number): Promise<T> {
  let timer: ReturnType<typeof setTimeout>;

  const deadline = new Promise<never>((_, reject) => {
    timer = setTimeout(() => reject(new Error(`timed out after ${ms}ms`)), ms);
  });

  return Promise.race([work, deadline]).finally(() => clearTimeout(timer));
}

Run a single test by part of its name with --filter. Wrapping the value in slashes treats it as a regular expression: ende test --filter "addition" control.test.ts ok | 1 passed | 0 failed | 2 filtered out ende test --filter "/add|sub/" control.test.ts

Stop at the first failure with --fail-fast, or after N failures with --fail-fast=N. Without it, the runner reports every failure: ende test --fail-fast control.test.ts

Rerun tests automatically whenever a file in the module graph changes: ende test --watch control.test.ts

Run test FILES in parallel across CPU cores. Tests inside one file still run sequentially; the ENDE_JOBS environment variable controls the worker count: ende test --parallel ENDE_JOBS=4 ende test --parallel

Run this example locally using the Ende CLI:

# ende test runs local files, so download the example first:
curl -O https://docs.ende.sh/examples/scripts/tests_run_control.ts
ende test tests_run_control.ts

Filtering and controlling test runs

Additional resources