Do not wrap all callbacks in promise

Promise will swallow exceptions in callback

Closes sindresorhus/got#84

index.js

@@ -37,29 +37,36 @@ module.exports = function read(stream, options, cb) {
 
 	if (options.encoding === undefined) { options.encoding = 'utf8'; }
 
-	var promise = new Promise(function (resolve, reject) {
-		var sink = new BufferStream();
+	var promise;
 
-		sink.on('finish', function () {
-			var data = Buffer.concat(this.buffer, this.length);
-
-			if (options.encoding) {
-				data = data.toString(options.encoding);
-			}
+	if (!cb) {
+		var resolve, reject;
+		promise = new Promise(function(_res, _rej) {
+			resolve = _res;
+			reject = _rej;
+		});
 
+		cb = function (err, data) {
+			if (err) { return reject(err); }
 			resolve(data);
-		});
+		};
+	}
 
-		stream.once('error', reject);
+	var sink = new BufferStream();
 
-		stream.pipe(sink);
-	});
+	sink.on('finish', function () {
+		var data = Buffer.concat(this.buffer, this.length);
 
-	if (!cb) {
-		return promise;
-	}
+		if (options.encoding) {
+			data = data.toString(options.encoding);
+		}
 
-	promise.then(function (data) {
 		cb(null, data);
-	}, cb);
-};
+	});
+
+	stream.once('error', cb);
+
+	stream.pipe(sink);
+
+	return promise;
+}

test.js

@@ -1,4 +1,4 @@
-/* global it */
+/* global describe, before, it, after */
 
 'use strict';
 var assert = require('assert');
@@ -86,3 +86,28 @@ it('should return Promise', function (done) {
 		done();
 	}, done);
 });
+
+describe('uncaughtException', function () {
+	before(function () {
+		this.listeners = process.listeners('uncaughtException');
+		process.removeAllListeners('uncaughtException');
+	});
+
+	it('should not swallow errors in callback', function (done) {
+		var stream = new Readable();
+		stream.push(null);
+
+		read(stream, function() {
+			throw new Error('uncaughtException');
+		});
+
+		process.on('uncaughtException', function (err) {
+			assert.equal(err.message, 'uncaughtException');
+			done();
+		});
+	});
+
+	after(function () {
+		this.listeners.forEach(process.on.bind(process, 'uncaughtException'));
+	});
+});