Date Time64 Test

1import { describe, expect, it } from "vitest";
2import { query } from "./clickhouse.js";
3import { NeedMoreData, Cursor } from "../src/readers/core.js";
4import { readDateTime64 } from "../src/readers/datetime.js";
5
6async function reader(expr: string): Promise<Cursor> {
7  return new Cursor(await query(`SELECT ${expr} FORMAT RowBinary`));
8}
9
10describe("readDateTime64", () => {
11  it("decodes P=3 to [Date (whole seconds), nanoseconds]", async () => {
12    const r = await reader("toDateTime64('2021-01-01 00:00:00.123', 3, 'UTC')");
13    const [date, nanos] = readDateTime64(3)(r);
14    expect(date.toISOString()).toBe("2021-01-01T00:00:00.000Z");
15    expect(nanos).toBe(123_000_000);
16    expect(r.pos).toBe(8);
17  });
18
19  it("keeps nanosecond precision (P=9) that a Date alone can't hold", async () => {
20    const [date, nanos] = readDateTime64(9)(
21      await reader("toDateTime64('2021-01-01 00:00:00.123456789', 9, 'UTC')"),
22    );
23    expect(date.toISOString()).toBe("2021-01-01T00:00:00.000Z");
24    expect(nanos).toBe(123456789);
25  });
26
27  it("decodes P=0 with a zero fraction", async () => {
28    const [date, nanos] = readDateTime64(0)(
29      await reader("toDateTime64('2021-01-01 00:00:00', 0, 'UTC')"),
30    );
31    expect(date.toISOString()).toBe("2021-01-01T00:00:00.000Z");
32    expect(nanos).toBe(0);
33  });
34
35  describe("advance() edge cases", () => {
36    it("throws NeedMoreData for every incomplete prefix (0 .. full.length-1)", async () => {
37      const full = await query(
38        "SELECT toDateTime64('2021-01-01 00:00:00.123', 3, 'UTC') FORMAT RowBinary",
39      );
40      for (let len = 0; len < full.length; len++) {
41        const r = new Cursor(full.subarray(0, len));
42        let thrown: unknown;
43        try {
44          readDateTime64(3)(r);
45        } catch (e) {
46          thrown = e;
47        }
48        expect(thrown, `prefix length ${len} of ${full.length}`).toBe(
49          NeedMoreData,
50        );
51      }
52    });
53  });
54});