docs: function processContent(target, opt, tagsRegExp, listOfFiles) {
  	let targetContent = String(target.contents);
  	const targetPath = target.path;
  	const files = extractFilePaths(targetContent, targetPath, opt, tagsRegExp);
  
  	// recursively process files
  	files.forEach(function (fileData) {
  		if (listOfFiles.indexOf(fileData.file.path) !== -1) {
  			throw error("Circular definition found. File: " + fileData.file.path + " referenced in a child file.");
  		}
  		listOfFiles.push(fileData.file.path);
  		const content = processContent(fileData.file, opt, tagsRegExp, listOfFiles);
  		listOfFiles.pop();
  
  		targetContent = inject(targetContent, String(content), opt, fileData.tags);
  	});
  	if (listOfFiles.length === 1 && !opt.quiet && files.length) {
  		log(
  			colors.cyan(files.length.toString()) +
  			' partials injected into ' +
  			colors.magenta(targetPath) +
  			'.');
  	}
  	return new Buffer.from(targetContent);
  }