njct/index.mjs

Inject a dependency

import isClass from 'node-is-class';
import { once } from '@zodash/once';

const dependencies = /* @__PURE__ */ new Map();
function provide(token, mock) {
  dependencies.set(token, mock);
}
function provideClass(token, ctor) {
  dependencies.set(token, once(() => new ctor()));
}
function clear() {
  dependencies.clear();
}
function inject() {
  const { 0: token, 1: factory, length } = arguments;
  if (!dependencies.has(token)) {
    if (typeof factory === "function") {
      return factory();
    }
    if (isClass(token)) {
      dependencies.set(token, once(() => new token()));
    } else if (length === 1) {
      throw new Error(`Cannot resolve ${token} dependency`);
    } else if (Object(factory) !== factory) {
      dependencies.set(token, () => factory);
    }
  }
  return dependencies.get(token)?.();
}
const injector = {
  provideClass,
  provide,
  clear
};

export { inject, injector };