@alwatr/dedupe/src/main.ts

A package manager helper tool for debug list of defined (imported) packages in your ecosystem and prevent to duplicate import (install) multiple versions of the same package in your project (deduplicate packages).

import type {DictionaryOpt} from '@alwatr/type-helper';
import {getGlobalThis} from '@alwatr/global-this';
import {hasOwn} from '@alwatr/has-own';

const globalThis_ = getGlobalThis<{__alwatr_dedupe__: string | true}>();

if (typeof globalThis_.__alwatr_dedupe__ === 'undefined') {
  globalThis_.__alwatr_dedupe__ = __package_version__;
} else {
  if (globalThis_.__alwatr_dedupe__ === true) {
    globalThis_.__alwatr_dedupe__ = '1.0.x';
  }

  console.error(
    new Error('duplication_detected', {
      cause: {
        name: __package_name__,
        oldVersion: globalThis_.__alwatr_dedupe__,
        newVersion: __package_version__,
      },
    }),
  );
}

const list: DictionaryOpt<true> = {};

/**
 * Prevent duplication in any entities like loading node packages.
 * @param name package name including scope. e.g. `@scope/package-name`
 * @param version package version (optional)
 *
 * @example
 * ```typescript
 * deduplicate({name: __package_name__, strict: true});
 * ```
 */
export function deduplicate(args: {name: string; strict?: true}): void {
  if (hasOwn(list, args.name)) {
    const error = new Error('duplication_detected', {
      cause: {
        name: args.name,
      },
    });

    if (args.strict) {
      throw error;
    } else {
      console.error(error);
    }
  }

  list[args.name] = true;
}

deduplicate({name: __package_name__});

/**
 * Old `definePackage` for backward compatibility.
 * @deprecated Use `deduplicate` instead.
 */
// eslint-disable-next-line @typescript-eslint/no-unused-vars
export function definePackage(packageName: string, _?: string): void {
  console.warn('`definePackage` in `@alwatr/dedupe` is deprecated. Use `deduplicate` instead.');
  deduplicate({name: packageName});
}