strom/tests/join.spec.ts

import { Readable } from "stream";
import test from "ava";
import { expect } from "chai";
import { join } from "../src";

test.cb("join() joins chunks using the specified separator", t => {
    t.plan(9);
    const source = new Readable({ objectMode: true });
    const expectedParts = ["ab|", "|", "c|d", "|", "|", "|", "e", "|", "|f|"];
    let i = 0;
    source
        .pipe(join("|"))
        .on("data", part => {
            expect(part).to.equal(expectedParts[i]);
            t.pass();
            i++;
        })
        .on("error", t.end)
        .on("end", t.end);

    source.push("ab|");
    source.push("c|d");
    source.push("|");
    source.push("e");
    source.push("|f|");
    source.push(null);
});

test.cb(
    "join() joins chunks using the specified separator without breaking up multi-byte characters " +
        "spanning multiple chunks",
    t => {
        t.plan(5);
        const source = new Readable({ objectMode: true });
        const expectedParts = ["ø", "|", "ö", "|", "一"];
        let i = 0;
        source
            .pipe(join("|"))
            .on("data", part => {
                expect(part).to.equal(expectedParts[i]);
                t.pass();
                i++;
            })
            .on("error", t.end)
            .on("end", t.end);

        source.push(Buffer.from("ø").slice(0, 1)); // 2-byte character spanning two chunks
        source.push(Buffer.from("ø").slice(1, 2));
        source.push(Buffer.from("ö").slice(0, 1)); // 2-byte character spanning two chunks
        source.push(Buffer.from("ö").slice(1, 2));
        source.push(Buffer.from("一").slice(0, 1)); // 3-byte character spanning three chunks
        source.push(Buffer.from("一").slice(1, 2));
        source.push(Buffer.from("一").slice(2, 3));
        source.push(null);
    },
);