var common = require('../common'); var assert = require('assert'); var zlib = require('zlib'); var path = require('path'); var fs = require('fs'); var file = fs.readFileSync(path.resolve(common.fixturesDir, 'person.jpg')), chunkSize = 24 * 1024, opts = { level: 9, strategy: zlib.Z_DEFAULT_STRATEGY }, deflater = zlib.createDeflate(opts); var chunk1 = file.slice(0, chunkSize), chunk2 = file.slice(chunkSize), blkhdr = new Buffer([0x00, 0x48, 0x82, 0xb7, 0x7d]), expected = Buffer.concat([blkhdr, chunk2]), actual; deflater.write(chunk1, function() { deflater.params(0, zlib.Z_DEFAULT_STRATEGY, function() { while (deflater.read()); deflater.end(chunk2, function() { var bufs = [], buf; while (buf = deflater.read()) bufs.push(buf); actual = Buffer.concat(bufs); }); }); while (deflater.read()); }); process.once('exit', function() { assert.deepEqual(actual, expected); });