agentsqripts/lib/performance/jsonInLoopDetector.js

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

/**
 * @file JSON in loop detector
 * @description Detects JSON operations in loops or hot paths
 */

/**
 * Detects JSON operations in loops or hot paths
 * @param {string} content - File content
 * @param {string} filePath - Path to the file
 * @returns {Array} Array of JSON performance issues
 */
function detectJSONInLoops(content, filePath) {
  const issues = [];
  const lines = content.split('\n');
  const { PERFORMANCE_PATTERNS } = require('./performancePatterns');
  
  let insideLoop = false;
  let loopDepth = 0;
  let loopStartLine = 0;
  
  lines.forEach((line, index) => {
    const lineNumber = index + 1;
    const trimmedLine = line.trim();
    
    // Track if we're inside a loop
    if (/for\s*\(|while\s*\(|\.forEach\s*\(|\.map\s*\(|\.filter\s*\(|\.reduce\s*\(/.test(trimmedLine)) {
      if (!insideLoop) {
        loopStartLine = lineNumber;
      }
      insideLoop = true;
      loopDepth++;
    }
    
    // Track loop end
    if (trimmedLine.includes('}') || trimmedLine.includes('});')) {
      loopDepth--;
      if (loopDepth <= 0) {
        insideLoop = false;
        loopDepth = 0;
      }
    }
    
    // Only flag JSON operations that are actually inside loops
    if ((line.includes('JSON.stringify') || line.includes('JSON.parse')) && insideLoop) {
        const pattern = PERFORMANCE_PATTERNS['json_in_loop'];
        const operation = line.includes('JSON.stringify') ? 'stringify' : 'parse';
        
        issues.push({
          type: 'json_in_loop',
          severity: pattern.severity,
          category: pattern.category,
          location: `${filePath}:${lineNumber}`,
          line: lineNumber,
          code: line.trim(),
          operation: operation,
          description: `Repeated JSON ${operation} detected in hot path`,
          summary: `Repeated JSON ${operation} detected in hot path`,
          recommendation: 'Cache serialized payload outside loop/request if static, or use streaming parser',
          effort: pattern.effort,
          impact: pattern.impact,
          estimatedSavings: '10-30% CPU gain per request'
        });
    }
  });
  
  return issues;
}

module.exports = {
  detectJSONInLoops
};