agentsqripts/lib/performance/memory-complexity/detect/detectMemoryLeaks.js

Comprehensive static code analysis toolkit for identifying technical debt, security vulnerabilities, performance issues, and code quality problems

/**
 * @file Detect memory leak patterns
 * @description Single responsibility: Detect common memory leak patterns in JavaScript
 */

const { iterateLines } = require('../../../utils/patternDetector');
const findCleanupPattern = require('../find/findCleanupPattern');

/**
 * Detect memory leak patterns
 */
function detectMemoryLeaks(lines, filePath) {
  const issues = [];
  
  iterateLines(lines, (line, lineNumber, trimmed, i) => {
    
    // Global variables that grow
    if (/global\.\w+\s*=\s*\[|window\.\w+\s*=\s*\[/.test(trimmed)) {
      issues.push({
        type: 'global_memory_leak',
        severity: 'HIGH',
        category: 'Memory',
        location: `${filePath}:${lineNumber}`,
        line: lineNumber,
        code: trimmed,
        description: 'Global variable assignment can lead to memory leaks',
        summary: 'Potential global memory leak',
        recommendation: 'Use local scope or implement proper cleanup',
        effort: 2,
        impact: 'Prevents memory leaks in long-running applications',
        estimatedSavings: 'prevents memory accumulation'
      });
    }
    
    // Event listeners without cleanup
    if (/addEventListener\s*\(/.test(trimmed) && 
        !findCleanupPattern(lines, i, 'removeEventListener')) {
      issues.push({
        type: 'event_listener_leak',
        severity: 'MEDIUM',
        category: 'Memory',
        location: `${filePath}:${lineNumber}`,
        line: lineNumber,
        code: trimmed,
        description: 'Event listener without corresponding removeEventListener',
        summary: 'Potential event listener memory leak',
        recommendation: 'Add removeEventListener in cleanup/unmount',
        effort: 1,
        impact: 'Prevents event listener accumulation',
        estimatedSavings: 'prevents listener memory leaks'
      });
    }
    
    // Timers without cleanup
    if (/setInterval\s*\(/.test(trimmed) && 
        !findCleanupPattern(lines, i, 'clearInterval')) {
      issues.push({
        type: 'timer_leak',
        severity: 'HIGH',
        category: 'Memory',
        location: `${filePath}:${lineNumber}`,
        line: lineNumber,
        code: trimmed,
        description: 'setInterval without corresponding clearInterval',
        summary: 'Timer memory leak',
        recommendation: 'Store interval ID and call clearInterval in cleanup',
        effort: 1,
        impact: 'Prevents timer accumulation and memory leaks',
        estimatedSavings: 'prevents timer memory leaks'
      });
    }
  });
  
  return issues;
}

module.exports = detectMemoryLeaks;