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typescript.unbounded_memory

Stability High

Detects data structures that can grow without bounds, leading to OOM.

Why It Matters

Unbounded memory:

Causes OOM — Process crashes
Cascading failures — Other services impacted
Hard to diagnose — Gradual memory growth

Example

// ❌ Before (unbounded array)
const events: Event[] = [];

socket.on('event', (event) => {
  events.push(event); // Grows forever!
});

// ✅ After (with limit)
import { CircularBuffer } from 'circular-buffer';

const events = new CircularBuffer<Event>(1000);

socket.on('event', (event) => {
  events.push(event); // Old events evicted
});

// Or with manual limit:
const MAX_EVENTS = 1000;
const events: Event[] = [];

socket.on('event', (event) => {
  if (events.length >= MAX_EVENTS) {
    events.shift();
  }
  events.push(event);
});

What Unfault Detects

Arrays growing in event handlers
Maps/Sets accepting unbounded input
Queues without size limits

Auto-Fix

Unfault adds capacity limits and bounds checks.