Carts Example Test

1import { describe, expect, it } from "vitest";
2import { query } from "./clickhouse.js";
3import { Cursor } from "../src/readers/core.js";
4import { type CartRow, readCartRow } from "../src/examples/carts.js";
5import { readRows } from "../src/readers/rows.js";
6
7/**
8 * Runs the `carts` example end to end (nested generics): an Array of named
9 * Tuples and an Array of Nullables. Populated via `JSONEachRow`; the second row
10 * is fully empty so both arrays read as a single count byte.
11 */
12describe("example: carts (nested generics via JSONEachRow)", () => {
13  it("creates, populates, and reads back through readCartRow", async () => {
14    const t = "rb_example_carts";
15    await query(`DROP TABLE IF EXISTS ${t}`);
16    await query(
17      `CREATE TABLE ${t} (` +
18        `cart_id UInt32, ` +
19        `items Array(Tuple(sku String, qty UInt16)), ` +
20        `discounts Array(Nullable(Int32))` +
21        `) ENGINE = Memory`,
22    );
23    try {
24      const rows = [
25        {
26          cart_id: 1,
27          items: [
28            { sku: "A", qty: 2 },
29            { sku: "B", qty: 1 },
30          ],
31          discounts: [10, null, 5],
32        },
33        { cart_id: 2, items: [], discounts: [] },
34      ];
35      await query(
36        `INSERT INTO ${t} FORMAT JSONEachRow\n` +
37          rows.map((r) => JSON.stringify(r)).join("\n"),
38      );
39
40      const r = new Cursor(
41        await query(
42          `SELECT cart_id, items, discounts FROM ${t} ORDER BY cart_id FORMAT RowBinary`,
43        ),
44      );
45      const out: CartRow[] = readRows(readCartRow)(r);
46      expect(out).toEqual([
47        {
48          cartId: 1,
49          items: [
50            { sku: "A", qty: 2 },
51            { sku: "B", qty: 1 },
52          ],
53          discounts: [10, null, 5],
54        },
55        { cartId: 2, items: [], discounts: [] },
56      ]);
57      expect(r.pos).toBe(r.buf.length);
58    } finally {
59      await query(`DROP TABLE IF EXISTS ${t}`);
60    }
61  });
62});