bun.sh/test/js/web/timers/setTimeout.test.js

import { spawnSync } from "bun";
import { heapStats } from "bun:jsc";
import { expect, it } from "bun:test";
import { bunEnv, bunExe, isWindows } from "harness";
import path from "node:path";

it("setTimeout", async () => {
  var lastID = -1;
  const result = await new Promise((resolve, reject) => {
    var numbers = [];

    for (let i = 0; i < 10; i++) {
      const id = setTimeout(
        (...args) => {
          numbers.push(i);
          if (i === 9) {
            resolve(numbers);
          }
          try {
            expect(args).toStrictEqual(["foo"]);
          } catch (err) {
            reject(err);
          }
        },
        i,
        "foo",
      );
      expect(+id > lastID).toBe(true);
      lastID = id;
    }
  });

  for (let j = 0; j < result.length; j++) {
    expect(result[j]).toBe(j);
  }
  expect(result.length).toBe(10);
});

it("clearTimeout", async () => {
  var called = false;

  // as object
  {
    const id = setTimeout(() => {
      called = true;
      expect.unreachable();
    }, 0);
    clearTimeout(id);

    // assert it doesn't crash if you call clearTimeout twice
    clearTimeout(id);
  }

  // as number
  {
    const id = setTimeout(() => {
      called = true;
      expect.unreachable();
    }, 0);
    clearTimeout(+id);

    // assert it doesn't crash if you call clearTimeout twice
    clearTimeout(+id);
  }

  await new Promise((resolve, reject) => {
    setTimeout(resolve, 10);
  });
  expect(called).toBe(false);
});

it.todo("setImmediate runs after setTimeout cb", async () => {
  var ranFirst = -1;
  setTimeout(() => {
    if (ranFirst === -1) ranFirst = 1;
  }, 0);
  setImmediate(() => {
    if (ranFirst === -1) ranFirst = 0;
  });

  await Bun.sleep(5);

  expect(ranFirst).toBe(1);
});

it("setTimeout(() => {}, 0)", async () => {
  var called = false;
  setTimeout(() => {
    called = true;
  }, 0);
  await new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve();
    }, 10);
  });
  expect(called).toBe(true);
  var ranFirst = -1;
  setTimeout(() => {
    if (ranFirst === -1) ranFirst = 0;
  }, 1);
  setTimeout(() => {
    if (ranFirst === -1) ranFirst = 1;
  }, 0);

  await new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve();
    }, 10);
  });
  expect(ranFirst).toBe(0);

  ranFirst = -1;

  const id = setTimeout(() => {
    ranFirst = 0;
  }, 0);
  clearTimeout(id);
  await new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve();
    }, 10);
  });
  expect(ranFirst).toBe(-1);
});

it("Bun.sleep", async () => {
  var sleeps = 0;
  await Bun.sleep(0);
  const start = performance.now();
  sleeps++;
  await Bun.sleep(1);
  sleeps++;
  await Bun.sleep(2);
  sleeps++;
  const end = performance.now();
  expect((end - start) * 1000).toBeGreaterThan(2);

  expect(sleeps).toBe(3);
});

it("Bun.sleep propagates exceptions", async () => {
  try {
    await Bun.sleep(1).then(a => {
      throw new Error("TestPassed");
    });
    throw "Should not reach here";
  } catch (err) {
    expect(err.message).toBe("TestPassed");
  }
});

const tolerance = 8;
it("Bun.sleep works with a Date object", async () => {
  const offset = isWindows ? 100 : 10;
  const init = performance.now();
  var ten_ms = new Date();
  ten_ms.setMilliseconds(ten_ms.getMilliseconds() + offset);
  await Bun.sleep(ten_ms);
  expect(Math.ceil(performance.now() - init + tolerance)).toBeGreaterThanOrEqual(offset);
});

it("Bun.sleep(Date) fulfills after Date", async () => {
  const offset = isWindows ? 100 : 50;
  let ten_ms = new Date();
  const init = performance.now();
  ten_ms.setMilliseconds(ten_ms.getMilliseconds() + offset);
  await Bun.sleep(ten_ms);
  expect(Math.ceil(performance.now() - init + tolerance)).toBeGreaterThanOrEqual(offset);
});

it("node.js timers/promises setTimeout propagates exceptions", async () => {
  const { setTimeout } = require("timers/promises");
  try {
    await setTimeout(1).then(a => {
      throw new Error("TestPassed");
    });
    throw "Should not reach here";
  } catch (err) {
    expect(err.message).toBe("TestPassed");
  }
});

it("order of setTimeouts", done => {
  var nums = [];
  var maybeDone = cb => {
    return () => {
      cb();
      if (nums.length === 4) {
        try {
          expect(nums).toEqual([1, 2, 3, 4]);
          done();
        } catch (e) {
          done(e);
        }
      }
    };
  };
  setTimeout(maybeDone(() => nums.push(2)));
  setTimeout(maybeDone(() => nums.push(3), 0));
  setTimeout(maybeDone(() => nums.push(4), 1));
  Promise.resolve().then(maybeDone(() => nums.push(1)));
});

it("setTimeout -> refresh", () => {
  const { exitCode, stdout } = spawnSync({
    cmd: [bunExe(), path.join(import.meta.dir, "setTimeout-unref-fixture.js")],
    env: bunEnv,
  });
  expect(exitCode).toBe(0);
  expect(stdout.toString()).toBe("SUCCESS\n");
});

it("setTimeout -> unref -> ref works", () => {
  const { exitCode, stdout } = spawnSync({
    cmd: [bunExe(), path.join(import.meta.dir, "setTimeout-unref-fixture-4.js")],
    env: bunEnv,
  });
  expect(exitCode).toBe(0);
  expect(stdout.toString()).toBe("TEST PASSED!\n");
});

it("setTimeout -> ref -> unref works, even if there is another timer", () => {
  const { exitCode, stdout } = spawnSync({
    cmd: [bunExe(), path.join(import.meta.dir, "setTimeout-unref-fixture-2.js")],
    env: bunEnv,
  });
  expect(exitCode).toBe(0);
  expect(stdout.toString()).toBe("");
});

it("setTimeout -> ref -> unref works", () => {
  const { exitCode, stdout } = spawnSync({
    cmd: [bunExe(), path.join(import.meta.dir, "setTimeout-unref-fixture-5.js")],
    env: bunEnv,
  });
  expect(exitCode).toBe(0);
  expect(stdout.toString()).toBe("");
});

it("setTimeout -> unref doesn't keep event loop alive forever", () => {
  const { exitCode, stdout } = spawnSync({
    cmd: [bunExe(), path.join(import.meta.dir, "setTimeout-unref-fixture-3.js")],
    env: bunEnv,
  });
  expect(exitCode).toBe(0);
  expect(stdout.toString()).toBe("");
});

it("setTimeout should refresh N times", done => {
  let count = 0;
  let timer = setTimeout(() => {
    count++;
    expect(timer.refresh()).toBe(timer);
  }, 50);

  setTimeout(() => {
    clearTimeout(timer);
    try {
      expect(count).toBeGreaterThanOrEqual(isWindows ? 4 : 5);
    } finally {
      done();
    }
  }, 300);
});

it("setTimeout if refreshed before run, should reschedule to run later", done => {
  let start = Date.now();
  let timer = setTimeout(() => {
    let end = Date.now();
    expect(end - start).toBeGreaterThan(120);
    done();
  }, 100);

  setTimeout(() => {
    timer.refresh();
  }, 50);
});

it("setTimeout should refresh after already been run", done => {
  let count = 0;
  let timer = setTimeout(() => {
    count++;
  }, 50);

  setTimeout(() => {
    timer.refresh();
  }, 100);

  setTimeout(() => {
    expect(count).toBe(2);
    done();
  }, 300);
});

it("setTimeout should not refresh after clearTimeout", done => {
  let count = 0;
  let timer = setTimeout(() => {
    count++;
  }, 50);

  clearTimeout(timer);

  timer.refresh();

  setTimeout(() => {
    expect(count).toBe(0);
    done();
  }, 100);
});

it("setTimeout Timeout objects are unprotected after called", async () => {
  let { promise, resolve } = Promise.withResolvers();

  const initial = heapStats().protectedObjectTypeCounts;
  let remaining = 2;
  setTimeout(() => {
    remaining--;
    if (remaining === 0) resolve();
  }, 0);
  setTimeout(() => {
    remaining--;
    if (remaining === 0) resolve();
  }, 0);
  expect(heapStats().protectedObjectTypeCounts.Timeout || 0).toEqual((initial.Timeout || 0) + 2);

  // Assert it's unprotected.
  await promise;

  expect(heapStats().protectedObjectTypeCounts.Timeout || 0).toEqual(initial.Timeout || 0);

  Bun.gc(true);
  remaining = 5;
  ({ promise, resolve } = Promise.withResolvers());
  setInterval(function () {
    remaining--;
    if (remaining === 0) {
      clearInterval(this);
      queueMicrotask(resolve);
    }
  });
  Bun.gc(true);
  await promise;
  expect(heapStats().protectedObjectTypeCounts.Timeout || 0).toEqual(initial.Timeout || 0);
});

it("setTimeout CPU usage #7790", async () => {
  const process = Bun.spawn({
    cmd: [bunExe(), "run", path.join(import.meta.dir, "setTimeout-cpu-fixture.js")],
    env: bunEnv,
    stdout: "inherit",
  });
  const code = await process.exited;
  expect(code).toBe(0);
  const stats = process.resourceUsage();
  expect(stats.cpuTime.total / BigInt(1e6)).toBeLessThan(1);
});

it("Returning a Promise in setTimeout doesnt keep the event loop alive forever", async () => {
  expect([path.join(import.meta.dir, "setTimeout-unref-fixture-6.js")]).toRun();
});

it("Returning a Promise in setTimeout (unref'd) doesnt keep the event loop alive forever", async () => {
  expect([path.join(import.meta.dir, "setTimeout-unref-fixture-7.js")]).toRun();
});

it("setTimeout canceling with unref, close, _idleTimeout, and _onTimeout", () => {
  expect([path.join(import.meta.dir, "timers-fixture-unref.js"), "setTimeout"]).toRun();
});