The Node.js performance testing tool with unit-test-like API.
- Runs each test in a separate process;
- Measures execution time using
performance; - Runs tested functions in multiple batches to reduce garbage collection interference;
- Warms up tested functions;
- Measures memory consumption using
process.memoryUsage.
npm install toofast --save-dev🔰 Usage
Let's write a performance test for a function that computes a factorial.
Create a file factorial.perf.js:
import { describe, test, measure } from 'toofast';
function factorial(x) {
return x === 0 ? 1 : x * factorial(x - 1);
}
describe('factorial', () => {
test('of 33', () => {
measure(() => {
factorial(33);
});
});
test('of 42', () => {
measure(() => {
factorial(42);
});
});
});Call toofast in the same directory with this file:
npx toofastTooFast package exports several callbacks that you can use in test file.
The minimum setup that you need in a test file is the test callback which encloses a group of measurements.
For example, let's say there's a function factorial which performance must be measured. Your whole test could be:
import { test, measure } from 'toofast';
test('factorial of 33', () => {
measure(() => {
factorial(33);
});
});The measure callback starts the performance measurement. It can be invoked multiple times inside a test block to
collect a data population from which an average results are derived.
test('factorial of 33 and 42', measure => {
measure(() => {
factorial(33);
});
measure(() => {
factorial(42);
});
});The measure callback returns a promise that is resolved as soon as performance measurement is completed.
Creates a block that groups together several related tests.
import { describe, test, measure } from 'toofast';
describe('factorial', () => {
test('of 42', measure => {
measure(() => {
factorial(42);
});
});
});describe blocks can be nested:
describe('Math', () => {
describe('factorial', () => {
// Tests go here
});
});Hooks are invoked at different phases of the performance test suite lifecycle: beforeEach, afterEach, afterWarmup,
beforeBatch, afterBatch, beforeIteration, and afterIteration.
The chart below demonstrates when they are called.
flowchart TD
describe --> testLifecycle
subgraph testLifecycle [Test lifecycle]
direction LR
subgraph warmup [Warmup]
direction TB
warmup_beforeWarmup(beforeWarmup) -->
warmup_beforeBatch(beforeBatch) -->
warmup_beforeIteration(beforeIteration) -->
warmup_callback[callback] -->
warmup_afterIteration(afterIteration) -->
warmup_afterBatch(afterBatch) -->
warmup_afterWarmup(afterWarmup)
end
subgraph batch [Measure]
direction TB
measure_beforeBatch(beforeBatch) -->
measure_beforeIteration(beforeIteration) -->
measure_callback[callback] -->
measure_afterIteration(afterIteration) -->
measure_afterBatch(afterBatch) -->
measure_beforeBatch
end
beforeEach(beforeEach) -->
test -->
warmup -->
batch -->
afterEach(afterEach)
end
Hooks can be registered at root level, or inside a describe or test block. Registered hooks affect all measure
calls that are nested in a block.
Hooks are always registered before any measurements are started, so the code below would first register beforeEach and
beforeIteration hooks and only after that would run measure.
import { beforeEach, beforeIteration, describe, test, measure } from 'toofast';
describe('factorial', () => {
beforeEach(() => {
// Runs before each test
});
test('of 42', () => {
measure(() => {
factorial(42);
});
beforeIteration(() => {
// Runs before each measure() iteration
});
});
});TooFast can automatically strip TypeScript types without any additional configuration if *.{ts,mts} files are
included:
toofast --include '**/*.perf.ts'This feature requires Node.js 22.6+.
By default, TooFast searches for .toofastrc, toofast.json, or toofast.config.js in the current working directory.
{
"testOptions": {
"measureTimeout": 5000
},
"include": [
"**/*.perf.js"
]
}testOptions-
The default test options used for all tests.
include-
The array of glob patterns of included test files. File paths are resolved relative to the config file. Defaults to
**/*.perf.{js,mjs,ts,mts}. setup-
The array of glob patters of files that are evaluated in the test environment before any test suites are run. File paths are resolved relative to the config file.
measureTimeout-
The maximum measure duration in milliseconds. Doesn't include the duration of warmup iterations. Defaults to 10_000.
targetRme-
The maximum relative margin of error that must be reached for each measurement [0, 1]. Defaults to 0.05.
warmupIterationCount-
The maximum number of warmup iterations that are run before each measurement. Defaults to 1. Set to 0 to disable warmup.
batchIterationCount-
The maximum number of iterations in a batch. Unlimited by default.
batchTimeout-
The maximum duration of batched measurements in milliseconds. Defaults to 1_000.
batchIntermissionTimeout-
The delay between batched measurements in milliseconds. VM is expected to run garbage collector during this delay. Defaults to 200.
--config-
The path to a configuration file.
toofast --config toofast.cfg
--include-
The array of glob patterns of included test files.
File paths are resolved relative to the current working directory. Provide this option multiple times to include multiple patterns.
includeoption is specified in a config file is overridden by--includearguments.toofast --include '**/*.perf.js' --include './perf/**/*.mjs'
--setup-
The array of glob patters of files that are evaluated in the test environment before any test suites are run.
File paths are resolved relative to the current working directory. Provide this option multiple times to include multiple patterns.
setupoption is specified in a config file is overridden by--setuparguments.toofast --setup setup.perf.js
--measureTimeout-
The maximum measure duration in milliseconds. Overrides
measureTimeouttest option. --targetRme-
The maximum relative margin of error that must be reached for each measurement [0, 1]. Overrides
targetRmetest option.toofast --targetRme 0.01
--warmupIterationCount-
The maximum number of warmup iterations that are run before each measurement. Overrides
warmupIterationCounttest option. --batchIterationCount-
The maximum number of iterations in a batch. Overrides
batchIterationCounttest option. --batchTimeout-
The maximum duration of batched measurements in milliseconds. Overrides
batchTimeouttest option. --batchIntermissionTimeout-
The delay between batched measurements in milliseconds. Overrides
batchIntermissionTimeouttest option. ...testPatterns-
The array of glob patterns to filter tests that must be executed across all included files.
toofast 'factorial*'
Provide option overrides to a particular describe, test and measure blocks.
Options provided to a block override both config options and command line arguments. Block-level options are propagate
to all underlying blocks as well.
import { describe, test, measure } from 'toofast';
describe('factorial', () => {
test('of 33', { warmupIterationCount: 1000 }, () => {
measure(() => {
factorial(33);
});
});
});