import { Readable } from "stream"; import test from "ava"; import { expect } from "chai"; import { concat, collect } from "../src"; test.cb( "concat() concatenates multiple readable streams (object, flowing mode)", t => { t.plan(6); const source1 = new Readable({ objectMode: true }); const source2 = new Readable({ objectMode: true }); const expectedElements = ["a", "b", "c", "d", "e", "f"]; let i = 0; concat(source1, source2) .on("data", (element: string) => { expect(element).to.equal(expectedElements[i]); t.pass(); i++; }) .on("error", t.end) .on("end", t.end); source1.push("a"); source2.push("d"); source1.push("b"); source2.push("e"); source1.push("c"); source2.push("f"); source2.push(null); source1.push(null); }, ); test.cb( "concat() concatenates multiple readable streams (object, paused mode)", t => { t.plan(6); const source1 = new Readable({ objectMode: true }); const source2 = new Readable({ objectMode: true }); const expectedElements = ["a", "b", "c", "d", "e", "f"]; let i = 0; const concatenation = concat(source1, source2) .on("readable", () => { let element = concatenation.read(); while (element !== null) { expect(element).to.equal(expectedElements[i]); t.pass(); i++; element = concatenation.read(); } }) .on("error", t.end) .on("end", t.end); source1.push("a"); source2.push("d"); source1.push("b"); source2.push("e"); source1.push("c"); source2.push("f"); source2.push(null); source1.push(null); }, ); test.cb( "concat() concatenates multiple readable streams (non-object, flowing mode)", t => { t.plan(6); const source1 = new Readable({ objectMode: false }); const source2 = new Readable({ objectMode: false }); const expectedElements = ["a", "b", "c", "d", "e", "f"]; let i = 0; concat(source1, source2) .on("data", (element: string) => { expect(element).to.deep.equal(Buffer.from(expectedElements[i])); t.pass(); i++; }) .on("error", t.end) .on("end", t.end); source1.push("a"); source2.push("d"); source1.push("b"); source2.push("e"); source1.push("c"); source2.push("f"); source2.push(null); source1.push(null); }, ); test.cb( "concat() concatenates multiple readable streams (non-object, paused mode)", t => { t.plan(6); const source1 = new Readable({ objectMode: false, read: () => ({}) }); const source2 = new Readable({ objectMode: false, read: () => ({}) }); const expectedElements = ["a", "b", "c", "d", "e", "f"]; let i = 0; const concatenation = concat(source1, source2) .on("readable", () => { let element = concatenation.read(); while (element !== null) { expect(element).to.deep.equal( Buffer.from(expectedElements[i]), ); t.pass(); i++; element = concatenation.read(); } }) .on("error", t.end) .on("end", t.end); source1.push("a"); setTimeout(() => source2.push("d"), 10); setTimeout(() => source1.push("b"), 20); setTimeout(() => source2.push("e"), 30); setTimeout(() => source1.push("c"), 40); setTimeout(() => source2.push("f"), 50); setTimeout(() => source2.push(null), 60); setTimeout(() => source1.push(null), 70); }, ); test.cb("concat() concatenates a single readable stream (object mode)", t => { t.plan(3); const source = new Readable({ objectMode: true }); const expectedElements = ["a", "b", "c", "d", "e", "f"]; let i = 0; concat(source) .on("data", (element: string) => { expect(element).to.equal(expectedElements[i]); t.pass(); i++; }) .on("error", t.end) .on("end", t.end); source.push("a"); source.push("b"); source.push("c"); source.push(null); }); test.cb( "concat() concatenates a single readable stream (non-object mode)", t => { t.plan(3); const source = new Readable({ objectMode: false }); const expectedElements = ["a", "b", "c", "d", "e", "f"]; let i = 0; concat(source) .on("data", (element: string) => { expect(element).to.deep.equal(Buffer.from(expectedElements[i])); t.pass(); i++; }) .on("error", t.end) .on("end", t.end); source.push("a"); source.push("b"); source.push("c"); source.push(null); }, ); test.cb("concat() concatenates empty list of readable streams", t => { t.plan(0); concat() .pipe(collect()) .on("data", _ => { t.fail(); }) .on("error", t.end) .on("end", t.end); });