fix(test): add regression tests for invites

server/src/lib/invites/invites.test.ts

@@ -0,0 +1,43 @@
+import { GetTotalAllowedInvites } from "./invites";
+import { ONE_MONTH } from "lib/constants/time";
+import { ServerConfig } from "lib/setup/config";
+import t from "tap";
+import { mkFakeUser } from "test-utils/misc";
+
+t.test("#GetTotalAllowedInvites", (t) => {
+	t.test("Should give the user more invites each month", (t) => {
+		t.equal(
+			GetTotalAllowedInvites(mkFakeUser(1, { joinDate: Date.now() })),
+			0,
+			"Should return 0 for a non-alpha/beta tester user who joined today."
+		);
+
+		t.equal(
+			GetTotalAllowedInvites(mkFakeUser(1, { joinDate: Date.now(), badges: ["beta"] })),
+			ServerConfig.INVITE_CODE_CONFIG?.BETA_USER_BONUS,
+			"Should return BETA_USER_BONUS for a beta tester user who joined today."
+		);
+		t.equal(
+			GetTotalAllowedInvites(mkFakeUser(1, { joinDate: Date.now(), badges: ["alpha"] })),
+			ServerConfig.INVITE_CODE_CONFIG?.BETA_USER_BONUS,
+			"Should return BETA_USER_BONUS for a alpha tester user who joined today."
+		);
+
+		t.equal(
+			GetTotalAllowedInvites(mkFakeUser(1, { joinDate: Date.now() - ONE_MONTH })),
+			ServerConfig.INVITE_CODE_CONFIG?.BATCH_SIZE,
+			"Should return BATCH_SIZE for a user who joined a month ago."
+		);
+
+		t.equal(
+			GetTotalAllowedInvites(mkFakeUser(1, { joinDate: Date.now() - ONE_MONTH * 2 })),
+			(ServerConfig.INVITE_CODE_CONFIG?.BATCH_SIZE ?? 0) * 2,
+			"Should return 2 * BATCH_SIZE for a user who joined two months ago."
+		);
+		t.equal(GetTotalAllowedInvites(mkFakeUser(1, { joinDate: 1638316800000 })), Infinity);
+
+		t.end();
+	});
+
+	t.end();
+});