memcheck-node

Automated memory leak regression testing for Node.js — detect growing object graphs in CI

Install

npm install memcheck-node

Usage

import memcheck, {assertNoLeaks, formatReport} from 'memcheck-node';

// Check a scenario for memory leaks
const result = await memcheck(async () => {
	// Your scenario: e.g., handle an HTTP request
	const data = processRequest({id: 1});
	return data;
}, {
	iterations: 5,
	allowedGrowth: 0.1, // Allow up to 10% heap growth
});

console.log(result.leaked);
// => false

console.log(formatReport(result));

// Or use assertNoLeaks in your tests
await assertNoLeaks(async () => {
	// This will throw if a leak is detected
	processRequest({id: 1});
});

API

memcheck(scenario, options?)

Returns: Promise<{leaked, snapshots, growth}>

Run a scenario function multiple times and detect memory leaks by monitoring heap growth.

scenario

Type: () => Promise<void> | void

A function that performs the operation to test.

options

iterations

Type: number
Default: 5

Number of snapshot cycles to run.

gcBetweenIterations

Type: boolean
Default: true

Force garbage collection between iterations. Requires --expose-gc flag or global.gc to be available.

allowedGrowth

Type: number
Default: 0.1

Maximum allowed heap growth as a decimal (0.1 = 10%).

Return value

• leaked — true if a memory leak was detected
• snapshots — Array of {usedHeapSize, totalHeapSize, iteration} objects
• growth — Percentage growth as a decimal

formatReport(result)

Returns: string

Format a memcheck result as a human-readable report.

assertNoLeaks(scenario, options?)

Returns: Promise<MemcheckResult>

Run memcheck and throw an error if a memory leak is detected. Useful in test suites.

Related

• v8 — Node.js V8 engine API

License

MIT