Function getPrefix

lib/internal/util/inspect.js:1026–1048

@type {(constructor: string, tag: string, fallback: string, size?: string) => string}

(constructor, tag, fallback, size = '')

/** @type {(constructor: string, tag: string, fallback: string, size?: string) => string} */
function getPrefix(constructor, tag, fallback, size = '') {
  if (constructor === null) {
    if (tag !== '' && fallback !== tag) {
      return `[${fallback}${size}: null prototype] [${tag}] `;
    }
    return `[${fallback}${size}: null prototype] `;
  }

  let result = `${constructor}${size} `;
  if (tag !== '') {
    const position = constructor.indexOf(tag);
    if (position === -1) {
      result += `[${tag}] `;
    } else {
      const endPos = position + tag.length;
      if (endPos !== constructor.length &&
        constructor[endPos] === constructor[endPos].toLowerCase()) {
        result += `[${tag}] `;
      }
    }
  }
  return result;
}

// Look up the keys of the object.
function getKeys(value, showHidden) {