Function resolveInjectedArguments

packages/context/src/resolver.ts:182–251

(
  target: object,
  method: string,
  ctx: Context,
  session?: ResolutionSession,
  // eslint-disable-next-line @typescript-eslint/no-explicit-any
  nonInjectedArgs?: any[],
)

 * @param nonInjectedArgs - Optional array of args for non-injected parameters
 */
export function resolveInjectedArguments(
  target: object,
  method: string,
  ctx: Context,
  session?: ResolutionSession,
  // eslint-disable-next-line @typescript-eslint/no-explicit-any
  nonInjectedArgs?: any[],
): ValueOrPromise<BoundValue[]> {
  /* istanbul ignore if */
  if (debug.enabled) {
    debug('Resolving injected arguments for %s', getTargetName(target, method));
  }
  const targetWithMethods = <{[method: string]: Function}>target;
  if (method) {
    assert(
      typeof targetWithMethods[method] === 'function',
      `Method ${method} not found`,
    );
  }
  // NOTE: the array may be sparse, i.e.
  //   Object.keys(injectedArgs).length !== injectedArgs.length
  // Example value:
  //   [ , 'key1', , 'key2']
  const injectedArgs = describeInjectedArguments(target, method);
  const extraArgs = nonInjectedArgs ?? [];

  let argLength = DecoratorFactory.getNumberOfParameters(target, method);

  // Please note `injectedArgs` contains `undefined` for non-injected args
  const numberOfInjected = injectedArgs.filter(i => i != null).length;
  if (argLength < numberOfInjected + extraArgs.length) {
    /**
     * `Function.prototype.length` excludes the rest parameter and only includes
     * parameters before the first one with a default value. For example,
     * `hello(@inject('name') name: string = 'John')` gives 0 for argLength
     */
    argLength = numberOfInjected + extraArgs.length;
  }

  let nonInjectedIndex = 0;
  return resolveList(new Array(argLength), (val, ix) => {
    // The `val` argument is not used as the resolver only uses `injectedArgs`
    // and `extraArgs` to return the new value
    const injection = ix < injectedArgs.length ? injectedArgs[ix] : undefined;
    if (
      injection == null ||
      (!injection.bindingSelector && !injection.resolve)
    ) {
      if (nonInjectedIndex < extraArgs.length) {
        // Set the argument from the non-injected list
        return extraArgs[nonInjectedIndex++];
      } else {
        const name = getTargetName(target, method, ix);
        throw new ResolutionError(
          `The argument '${name}' is not decorated for dependency injection ` +
            'but no value was supplied by the caller. Did you forget to apply ' +
            '@inject() to the argument?',
          {context: ctx, options: {session}},