import { Readable } from "stream"; import test from "ava"; import { expect } from "chai"; import { batch, map, fromArray } from "../src"; test.cb("batch() batches chunks together", t => { t.plan(3); const source = new Readable({ objectMode: true }); const expectedElements = [["a", "b", "c"], ["d", "e", "f"], ["g"]]; let i = 0; source .pipe(batch(3)) .on("data", (element: string[]) => { t.deepEqual(element, expectedElements[i]); i++; }) .on("error", t.end) .on("end", t.end); source.push("a"); source.push("b"); source.push("c"); source.push("d"); source.push("e"); source.push("f"); source.push("g"); source.push(null); }); test.cb("batch() yields a batch after the timeout", t => { t.plan(3); const source = new Readable({ objectMode: true, read(size: number) { return; }, }); const expectedElements = [["a", "b"], ["c"], ["d"]]; let i = 0; source .pipe(batch(3, 500)) .on("data", (element: string[]) => { t.deepEqual(element, expectedElements[i]); i++; }) .on("error", t.fail) .on("end", t.end); source.push("a"); source.push("b"); setTimeout(() => { source.push("c"); }, 600); setTimeout(() => { source.push("d"); source.push(null); }, 600 * 2); }); test.cb( "batch() yields all input data even when the last element(s) dont make a full batch", t => { const data = [1, 2, 3, 4, 5, 6, 7]; fromArray([...data]) .pipe(batch(3)) .pipe( map(d => { t.deepEqual( d, [data.shift(), data.shift(), data.shift()].filter( x => !!x, ), ); }), ) .on("error", t.fail) .on("finish", () => { t.is(data.length, 0); t.end(); }); }, );