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Code reviewHardcr-g254
Subject SecurityLevel Senior–Staff~30 minCommon in Security interviewsIndustries Software development

Question

Review this JS deep-merge used to apply user-supplied config over defaults.

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Code to reviewjs
function deepMerge(target, source) {  for (const key in source) {    if (typeof source[key] === 'object' && source[key] !== null) {      target[key] = target[key] || {};      deepMerge(target[key], source[key]);    } else {      target[key] = source[key];    }  }  return target;}// usage: deepMerge(defaults, JSON.parse(req.body.config))
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