alias.spec.mjs

import assert from 'node:assert/strict';
import {
	before,
	describe,
	test,
} from 'node:test';

import * as td from 'testdouble';

import { nextResolve } from './nextResolve.fixture.mjs';


describe('alias', () => {
	const readFile = td.func('mock_readFile');
	const base = 'file://';
	const aliases = {
		'…/*': ['./src/*'],
		'ENV': ['https://example.com/env.json'],
		'VARS': ['/vars.json'],
	};

	class ENOENT extends Error {
		code = 'ENOENT';
	}

	before(async () => {
		await td.replaceEsm('node:fs/promises', { readFile });
		const nodeUrl = await import('node:url');
		await td.replaceEsm('node:url', { ...nodeUrl, pathToFileURL() { return new URL(base) } });
	});

	describe('that are in tsconfig.json', async () => {
		let resolve;

		before(async () => {
			td.when(readFile(td.matchers.contains('/package.json')))
				.thenReject(new ENOENT()); // shouldn't matter
			td.when(readFile(td.matchers.contains('/tsconfig.json')))
				.thenResolve(JSON.stringify({ compilerOptions: { paths: aliases } }));

			({ resolve } = await import('./alias.mjs'));
		});

		await test(() => runCases(resolve));
	});

	describe('that are in package.json', async () => {
		let resolve;

		before(async () => {
			td.when(readFile(td.matchers.contains('/package.json')))
				.thenResolve(JSON.stringify({ aliases }));
			td.when(readFile(td.matchers.contains('/tsconfig.json')))
				.thenReject(new ENOENT()); // must be voided so package.json gets checked

			({ resolve } = await import('./alias.mjs'));
		});

		await test(() => runCases(resolve));
	});

	async function runCases(resolve) {
		await test('should de-alias a prefixed specifier', async () => {
			assert.equal(
				(await resolve('…/test.mjs', {}, nextResolve)).url,
				`${base}/src/test.mjs`,
			);
		});

		await test('should de-alias a pointer (fully-qualified url) specifier', async () => {
			assert.equal(
				(await resolve('ENV', {}, nextResolve)).url,
				aliases.ENV[0],
			);
		});

		await test('should de-alias a pointer (absolute path) specifier', async () => {
			assert.equal(
				(await resolve('VARS', {}, nextResolve)).url,
				aliases.VARS[0],
			);
		});

		await test('should maintain any suffixes on the prefixed specifier', async () => {
			assert.equal(
				(await resolve('…/test.mjs?foo', {}, nextResolve)).url,
				`${base}/src/test.mjs?foo`,
			);
			assert.equal(
				(await resolve('…/test.mjs#bar', {}, nextResolve)).url,
				`${base}/src/test.mjs#bar`,
			);
			assert.equal(
				(await resolve('…/test.mjs?foo#bar', {}, nextResolve)).url,
				`${base}/src/test.mjs?foo#bar`,
			);
		});

		await test('should maintain any suffixes on the pointer (fully-qualified url) specifier', async () => {
			assert.equal(
				(await resolve('ENV?foo', {}, nextResolve)).url,
				`${aliases.ENV[0]}?foo`,
			);
			assert.equal(
				(await resolve('ENV#bar', {}, nextResolve)).url,
				`${aliases.ENV[0]}#bar`,
			);
			assert.equal(
				(await resolve('ENV?foo#bar', {}, nextResolve)).url,
				`${aliases.ENV[0]}?foo#bar`,
			);
		});

		await test('should maintain any suffixes on the pointer (absolute path) specifier', async () => {
			assert.equal(
				(await resolve('VARS?foo', {}, nextResolve)).url,
				`${aliases.VARS[0]}?foo`,
			);
			assert.equal(
				(await resolve('VARS#bar', {}, nextResolve)).url,
				`${aliases.VARS[0]}#bar`,
			);
			assert.equal(
				(await resolve('VARS?foo#bar', {}, nextResolve)).url,
				`${aliases.VARS[0]}?foo#bar`,
			);
		});
	}
});