write csv

write_csv.ts

const requires_quoting_regex = /["\n,]/

const escape_quotes = (str: string) => str.replace(/"/g, `""`)

export const escape_csv_value = (str: string) => requires_quoting_regex.test(str)
	? `"${ escape_quotes(str) }"`
	: str

export const csv_line = (...values: string[]) => values.map(escape_csv_value).join(`,`)

export const objects_to_csv = (array: { [k: string]: string }[]) => {
	const all_keys = [ ...new Set(array.map(Object.keys).flat()) ]

	return [
		all_keys,
		...array.map(object => all_keys.map(key => object[key] || ``)),
	].map(values => csv_line(...values)).join(`\n`)
}