'use strict'; const common = require('../common'); const assert = require('assert'); const stream = require('stream'); { // This test ensures that the stream implementation correctly handles values // for highWaterMark which exceed the range of signed 32 bit integers and // rejects invalid values. // This number exceeds the range of 32 bit integer arithmetic but should still // be handled correctly. const ovfl = Number.MAX_SAFE_INTEGER; const readable = stream.Readable({ highWaterMark: ovfl }); assert.strictEqual(readable._readableState.highWaterMark, ovfl); const writable = stream.Writable({ highWaterMark: ovfl }); assert.strictEqual(writable._writableState.highWaterMark, ovfl); for (const invalidHwm of [true, false, '5', {}, -5, NaN]) { for (const type of [stream.Readable, stream.Writable]) { common.expectsError(() => { type({ highWaterMark: invalidHwm }); }, { type: TypeError, code: 'ERR_INVALID_OPT_VALUE', message: `The value "${invalidHwm}" is invalid for option "highWaterMark"` }); } } } { // This test ensures that the push method's implementation // correctly handles the edge case where the highWaterMark and // the state.length are both zero const readable = stream.Readable({ highWaterMark: 0 }); for (let i = 0; i < 3; i++) { const needMoreData = readable.push(); assert.strictEqual(needMoreData, true); } } { // This test ensures that the read(n) method's implementation // correctly handles the edge case where the highWaterMark, state.length // and n are all zero const readable = stream.Readable({ highWaterMark: 0 }); readable._read = common.mustCall(); readable.read(0); }