Preview:
const camelToSnakeCase = (text) => {
  if (!(typeof text === "string" || text instanceof String)) {
    console.error(`string expected, ${typeof text} provided`)
    return text
  }
  return text.replace(/[A-Z]/g, (letter) => `_${letter.toLowerCase()}`)
}

camelToSnakeCase("camelCaseToSnakeCase") // camel_case_to_snake_case
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