Function format

repos/effect/packages/effect/src/Formatter.ts:116–199

(input: unknown, options?: {
  readonly space?: number | string | undefined
  readonly ignoreToString?: boolean | undefined
})

  const ind = (d: number) => gap.repeat(d)

  const wrap = (v: unknown, body: string): string => {
    const ctor = (v as any)?.constructor
    return ctor && ctor !== Object.prototype.constructor && ctor.name ? `${ctor.name}(${body})` : body
  }

  const ownKeys = (o: object): Array<PropertyKey> => {
    try {
      return Reflect.ownKeys(o)
    } catch {
      return ["[ownKeys threw]"]
    }
  }

  function recur(v: unknown, d = 0): string {
    if (Array.isArray(v)) {
      if (ancestors.has(v)) return CIRCULAR
      ancestors.add(v)
      const output = !gap || v.length <= 1
        ? `[${v.map((x) => recur(x, d)).join(",")}]`
        : `[\n${ind(d + 1)}${v.map((x) => recur(x, d + 1)).join(",\n" + ind(d + 1))}\n${ind(d)}]`
      ancestors.delete(v)
      return output
    }

    if (v instanceof Date) return formatDate(v)

    if (
      !options?.ignoreToString &&
      Predicate.hasProperty(v, "toString") &&
      typeof v["toString"] === "function" &&
      v["toString"] !== Object.prototype.toString &&
      v["toString"] !== Array.prototype.toString
    ) {
      const s = safeToString(v)
      if (v instanceof Error && v.cause) {
        return `${s} (cause: ${recur(v.cause, d)})`
      }
      return s
    }

    if (typeof v === "string") return JSON.stringify(v)

    if (
      typeof v === "number" ||
      v == null ||
      typeof v === "boolean" ||
      typeof v === "symbol"
    ) return String(v)

    if (typeof v === "bigint") return String(v) + "n"

    if (typeof v === "object" || typeof v === "function") {
      if (ancestors.has(v)) return CIRCULAR
      ancestors.add(v)

      let output: string
      if (symbolRedactable in v) {
        output = format(getRedacted(v as any))