feat: add checkLicense

Author: velut

lib/utils/check-license.test.ts

@@ -0,0 +1,40 @@
+import { goTry } from "go-go-try";
+import { expect, test } from "vitest";
+import { checkLicense } from "./check-license";
+
+test("undefined", () => {
+	const [err] = goTry(() => checkLicense());
+	expect(err).toBeDefined();
+});
+
+test("empty", () => {
+	const [err] = goTry(() => checkLicense(""));
+	expect(err).toBeDefined();
+});
+
+test("unlicensed", () => {
+	const [err1] = goTry(() => checkLicense("UNLICENSED"));
+	const [err2] = goTry(() => checkLicense("unlicensed"));
+	expect(err1).toBeDefined();
+	expect(err2).toBeDefined();
+});
+
+test("see license in ...", () => {
+	const [err1] = goTry(() => checkLicense("SEE LICENSE IN ..."));
+	const [err2] = goTry(() => checkLicense("see license in ..."));
+	const [err3] = goTry(() => checkLicense("See license in ..."));
+	expect(err1).toBeDefined();
+	expect(err2).toBeDefined();
+	expect(err3).toBeDefined();
+});
+
+test("valid licenses", () => {
+	const [err1] = goTry(() => checkLicense("MIT"));
+	const [err2] = goTry(() => checkLicense("Apache-2.0"));
+	const [err3] = goTry(() => checkLicense("MIT AND Apache-2.0"));
+	const [err4] = goTry(() => checkLicense("(ISC OR GPL-4.0)"));
+	expect(err1).toBeUndefined();
+	expect(err2).toBeUndefined();
+	expect(err3).toBeUndefined();
+	expect(err4).toBeUndefined();
+});

lib/utils/check-license.ts

@@ -0,0 +1,7 @@
+export function checkLicense(license = "") {
+	// See https://docs.npmjs.com/cli/v10/configuring-npm/package-json#license
+	license = license.trim().toLowerCase();
+	if (!license) throw new Error("no license");
+	if (license.startsWith("unlicense")) throw new Error("unlicensed");
+	if (license.startsWith("see ")) throw new Error("external license");
+}