Function getUserOptions

lib/internal/util/inspect.js:299–345

(ctx, isCrossContext)

let getStringWidth;

function getUserOptions(ctx, isCrossContext) {
  const ret = {
    stylize: ctx.stylize,
    showHidden: ctx.showHidden,
    depth: ctx.depth,
    colors: ctx.colors,
    customInspect: ctx.customInspect,
    showProxy: ctx.showProxy,
    maxArrayLength: ctx.maxArrayLength,
    maxStringLength: ctx.maxStringLength,
    breakLength: ctx.breakLength,
    compact: ctx.compact,
    sorted: ctx.sorted,
    getters: ctx.getters,
    numericSeparator: ctx.numericSeparator,
    ...ctx.userOptions,
  };

  // Typically, the target value will be an instance of `Object`. If that is
  // *not* the case, the object may come from another vm.Context, and we want
  // to avoid passing it objects from this Context in that case, so we remove
  // the prototype from the returned object itself + the `stylize()` function,
  // and remove all other non-primitives, including non-primitive user options.
  if (isCrossContext) {
    ObjectSetPrototypeOf(ret, null);
    for (const key of ObjectKeys(ret)) {
      if ((typeof ret[key] === 'object' || typeof ret[key] === 'function') &&
          ret[key] !== null) {
        delete ret[key];
      }
    }
    ret.stylize = ObjectSetPrototypeOf((value, flavour) => {
      let stylized;
      try {
        stylized = `${ctx.stylize(value, flavour)}`;
      } catch {
        // Continue regardless of error.
      }

      if (typeof stylized !== 'string') return value;
      // `stylized` is a string as it should be, which is safe to pass along.
      return stylized;
    }, null);
  }

  return ret;
}

/**
 * Echos the value of any input. Tries to print the value out