strom/tests/split.spec.ts

import { Readable } from "stream";
import test from "ava";
import { expect } from "chai";
import { strom } from "../src";
const { split } = strom();

test.cb("split() splits chunks using the default separator (\\n)", t => {
    t.plan(5);
    const source = new Readable({ objectMode: true });
    const expectedParts = ["ab", "c", "d", "ef", ""];
    let i = 0;
    source
        .pipe(split())
        .on("data", part => {
            expect(part).to.equal(expectedParts[i]);
            t.pass();
            i++;
        })
        .on("error", t.end)
        .on("end", t.end);

    source.push("ab\n");
    source.push("c");
    source.push("\n");
    source.push("d");
    source.push("\nef\n");
    source.push(null);
});

test.cb("split() splits chunks using the specified separator", t => {
    t.plan(6);
    const source = new Readable({ objectMode: true });
    const expectedParts = ["ab", "c", "d", "e", "f", ""];
    let i = 0;
    source
        .pipe(split("|"))
        .on("data", (part: string) => {
            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(
    "split() splits utf8 encoded buffers using the specified separator",
    t => {
        t.plan(3);
        const expectedElements = ["a", "b", "c"];
        let i = 0;
        const through = split(",");
        const buf = Buffer.from("a,b,c");
        through
            .on("data", element => {
                expect(element).to.equal(expectedElements[i]);
                i++;
                t.pass();
            })
            .on("error", t.end)
            .on("end", t.end);

        for (let j = 0; j < buf.length; ++j) {
            through.write(buf.slice(j, j + 1));
        }
        through.end();
    },
);

test.cb(
    "split() splits utf8 encoded buffers with multi-byte characters using the specified separator",
    t => {
        t.plan(3);
        const expectedElements = ["一", "一", "一"];
        let i = 0;
        const through = split(",");
        const buf = Buffer.from("一,一,一"); // Those spaces are multi-byte utf8 characters (code: 4E00)
        through
            .on("data", element => {
                expect(element).to.equal(expectedElements[i]);
                i++;
                t.pass();
            })
            .on("error", t.end)
            .on("end", t.end);

        for (let j = 0; j < buf.length; ++j) {
            through.write(buf.slice(j, j + 1));
        }
        through.end();
    },
);