test-setup.js

const tsConfigPaths = require("tsconfig-paths")
const fs = require("fs")
const path = require("path")

const baseUrl = path.resolve(__dirname)

const tsConfig = JSON.parse(fs.readFileSync(path.join(baseUrl, "tsconfig.json"), "utf-8"))

/**
 * The aliases point towards the `src` directory.
 * However, `tsc` doesn't compile paths by itself
 * (https://www.typescriptlang.org/docs/handbook/modules/reference.html#paths-does-not-affect-emit)
 * So we need to use tsconfig-paths to resolve the aliases when running tests,
 * but pointing to `out` instead.
 */
const outPaths = {}
Object.keys(tsConfig.compilerOptions.paths).forEach((key) => {
	const value = tsConfig.compilerOptions.paths[key]
	outPaths[key] = value.map((path) => path.replace("src", "out/src"))
})

tsConfigPaths.register({
	baseUrl: baseUrl,
	paths: outPaths,
})