@jil/args/src/parseInContext.ts

A convention based argument parsing and formatting library, with strict validation checks

import {ArgsError} from './errors';
import {parse} from './parse';
import {ArgList, Arguments, Argv, ContextFactory, ParserOptions, PrimitiveType} from './types';

/**
 * Parse a list of command line arguments (typically from `process.argv`) into an arguments
 * object using a context factory. The factory can customize the parser options based on the
 * arguments being parsed.
 */
export function parseInContext<O extends object = {}, P extends PrimitiveType[] = ArgList>(
  argv: Argv,
  context: ContextFactory,
): Arguments<O, P> {
  let options: ParserOptions<O, P> | undefined;

  // Loop through each arg until we find a context
  argv.some(arg => {
    options = context(arg, argv) as ParserOptions<O, P>;

    return !!options;
  });

  // Fail if context not found
  if (!options) {
    throw new ArgsError('CONTEXT_REQUIRED');
  }

  return parse(argv, options);
}